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UCAR®<br />
Solution<br />
<strong>Vinyl</strong> <strong>Resins</strong><br />
for Coatings<br />
U
IMPORTANT:<br />
Union Carbide Corporation has compiled the information<br />
contained herein from what it believes are authoritative<br />
sources and believes that it is accurate and factual as of<br />
the date printed. It is offered solely as a convenience to<br />
its customers and intended only as a guide concerning the<br />
products mentioned. Since the user’s product formulation,<br />
specific use application, and conditions of use are beyond<br />
Union Carbide’s control, Union Carbide makes no warranty<br />
or representation regarding the results that may be<br />
obtained by the user. It shall be the responsibility of the<br />
user to determine the suitability of any products mentioned<br />
for the user’s specific application. This information is not<br />
to be taken as a warranty or representation for which<br />
Union Carbide assumes legal responsibility nor as permission<br />
to practice any patented invention without a license.<br />
FOOD, DRUG, OR COSMETIC<br />
No chemical should be used as or in a food, drug, or<br />
cosmetic, or in a product or process in which it may contact<br />
a food, drug, or cosmetic, until the user has determined the<br />
safety and legality of the use. Since government regulations<br />
and use conditions are subject to change, it is the user’s<br />
responsibility to determine that the information contained<br />
herein is appropriate and suitable under the current,<br />
applicable laws and regulations.<br />
Many chemicals of a toxic nature are discussed in this publication.<br />
Before using any of them, we urge you to contact<br />
the supplier and obtain the Material Safety Data Sheet and<br />
other safety information so that you can take the necessary<br />
measures to protect the health and safety of your workers.<br />
CELLOSOLVE, FLEXOL, PROPASOL, UCAR, UCARMAG, and<br />
UNION CARBIDE are registered trademarks of Union Carbide.<br />
Copyright © 1980, 1983, 1988, 1990, 1992, 1994, 1996, 1998<br />
Union Carbide.<br />
Contents<br />
UCAR® Solution <strong>Vinyl</strong> <strong>Resins</strong> for Coatings|1<br />
Typical Properties Table|2<br />
Applications Table|4<br />
General Characteristics Table|4<br />
FDA Status|5<br />
<strong>Vinyl</strong> Chloride/<strong>Vinyl</strong> Acetate Copolymers|6<br />
Carboxyl-Modified <strong>Vinyl</strong> Chloride/<br />
<strong>Vinyl</strong> Acetate Copolymers|7<br />
Epoxy-Modified <strong>Vinyl</strong> Chloride/<br />
<strong>Vinyl</strong> Acetate Copolymers|7<br />
Hydroxyl-Modified <strong>Vinyl</strong> Chloride/<br />
<strong>Vinyl</strong> Acetate Copolymers|8<br />
Hydrolyzed <strong>Resins</strong>|8<br />
Directly-Polymerized <strong>Resins</strong>|8<br />
UCARMAG® 527 and 569 <strong>Resins</strong>|9<br />
Solution <strong>Vinyl</strong> <strong>Resins</strong> for<br />
VOC-Compliant Coatings|9<br />
Solutions|9<br />
Viscosity Behavior|19<br />
Application Methods|20<br />
Solution Preparation|20<br />
Formulation of Clear Coatings|22<br />
Plasticizers|22<br />
Heat Stabilizers|22<br />
Light Stabilizers|23<br />
Formulation of Pigmented Coatings|24<br />
Modification with Other Polymers|27<br />
Compatibility|27<br />
Reactive (Crosslinking) Systems|27<br />
Adhesion|29<br />
Where Not to Use <strong>Vinyl</strong> Coatings|29<br />
Product Safety|31<br />
Further Information|31<br />
Emergency Service|32
UCAR ® Solution <strong>Vinyl</strong> <strong>Resins</strong> for Coatings<br />
Through advanced solution vinyl resin<br />
technology, Union Carbide has successfully<br />
extended the 50 years of proven performance<br />
of the vinyl chloride backbone.<br />
UCAR® Solution <strong>Vinyl</strong> <strong>Resins</strong> are available in four general<br />
copolymer types:<br />
■ <strong>Vinyl</strong> Chloride/<strong>Vinyl</strong> Acetate<br />
■ Carboxyl-Modified <strong>Vinyl</strong> Chloride/<strong>Vinyl</strong> Acetate<br />
■ Epoxy-Modified <strong>Vinyl</strong> Chloride/<strong>Vinyl</strong> Acetate<br />
■ Hydroxyl-Modified <strong>Vinyl</strong> Chloride/<strong>Vinyl</strong> Acetate<br />
These copolymers are available as powders and solutions<br />
in a range of molecular weights and compositions.<br />
Coatings based on these resins are non-oxidizing and<br />
permanently flexible, and are characterized by the<br />
absence of color, odor, and taste. They are not attacked<br />
at normal temperatures by dilute alkalies or mineral<br />
acids, alcohols, greases, oils, or aliphatic hydrocarbons.<br />
They have a low moisture-vapor transmission rate, low<br />
order of water absorption, and are tough and durable.<br />
The molecular weight and the ratio of vinyl chloride<br />
to vinyl acetate affect the solubility and other physical<br />
properties of the resin. As the molecular weight (degree<br />
of polymerization) is increased, the solution viscosity<br />
increases and the strength of the film increases. <strong>Vinyl</strong><br />
chloride contributes film strength and toughness, as well<br />
as water and chemical resistance. <strong>Vinyl</strong> acetate improves<br />
solubility and film flexibility.<br />
When properly pigmented, coatings based on vinyl<br />
chloride/acetate copolymers have excellent outdoor<br />
durability. Hydroxyl-modification improves compatibility<br />
and adhesion, and provides a site for crosslinking.<br />
Carboxyl modification permits formulation of coatings<br />
that will adhere to clean metal surfaces on air-dry.<br />
Epoxy modification provides the ability to crosslink with<br />
carboxyl-modified vinyl resins to give an all-vinyl reactive<br />
system that yields thermoset-like characteristics, most<br />
notably improved toughness, enhanced physical<br />
properties, and superior chemical resistance.<br />
UCAR Solution <strong>Vinyl</strong> <strong>Resins</strong>, produced by a proprietary<br />
solution polymerization process, offer several advantages:<br />
High Purity<br />
No water-soluble suspending agents or surfactants are<br />
used in the manufacture; therefore, water resistance is<br />
outstanding. Additionally, the as-received vinyl chloride<br />
monomer (VCM) content of dry vinyl powders is
2<br />
Typical Properties of UCAR ® Solution <strong>Vinyl</strong> <strong>Resins</strong><br />
table 1<br />
UCAR® Solution <strong>Vinyl</strong> <strong>Resins</strong><br />
Polymer Composition % by Wt<br />
VCl 90 86 86 86 83 81<br />
VAc 10 14 14 13 16 17<br />
Other — — — 1a 1a 2a VYNS-3 VYHH VYHD VMCH VMCC VMCA<br />
Reactive Functionality<br />
Type — — — carboxyl carboxyl carboxyl<br />
% by Wt — — — 1.0 1.0 2.0<br />
Acid No. — — — 10 10 19<br />
Hydroxyl Value — — — — — —<br />
Epoxy Equivalent Wt — — — — — —<br />
Inherent Viscosity ASTM-D1243 0.74 0.50 0.40 0.50 0.38 0.32<br />
Specific Gravity ASTM-D792 1.36 1.35 1.35 1.35 1.34 1.34<br />
Glass Transition Temp. (Tg), ºC 79 72 72 74 72 70<br />
Average Molecular Wt, Mn* 44,000 27,000 22,000 27,000 19,000 15,000<br />
Solution Viscosity h at 25ºC, cP 1300 j 600 200 650 100 55<br />
Typical Solution Properties<br />
Solids, % by Wt 15 20 25 20 25 30<br />
MEK/Toluene 67/33 50/50 33/67 50/50 25/75 25/75<br />
Viscosity at 25ºC, cP 250 200 175 150 250 370<br />
(a) Maleic acid<br />
(b) Epoxy-containing monomer<br />
(c) Solution — 40% resin in MEK/toluene, 3/2 by wt<br />
(d) <strong>Vinyl</strong> alcohol<br />
(e) Hydroxyalkyl acrylate<br />
* Referenced to polystyrene standard.<br />
(f) Oxirane oxygen<br />
(g) On solids<br />
(h) 30% resin in MEK<br />
(j) 20% resin in MEK<br />
(k) Sulfonate-containing monomer
UCARMAG® Binder<br />
VERR-40 VAGH VAGD VAGF VAGC VROH 527 569<br />
82 90 90 81 81 81 82 85<br />
9 4 4 4 4 4 4 13<br />
9 b,c 6 d 6 d 15 e 15 e 15 e 14 a,e 2 k<br />
epoxy hydroxyl hydroxyl hydroxyl hydroxyl hydroxyl hydroxyl/ sulfonate<br />
carboxyl<br />
1.8 f,g 2.3 2.3 1.8 1.9 2.0 2.0 1.0<br />
— — — — — — — —<br />
— 76 76 59 63 66 59 —<br />
1600 g — — — — — —<br />
— 0.53 0.44 0.56 0.44 0.30 0.56 0.40<br />
— 1.39 1.39 1.37 1.36 1.37 1.37 1.35<br />
67 79 77 70 65 65 72 72<br />
15,000 27,000 22,000 33,000 24,000 15,000 35,000 22,000<br />
— 1000 400 930 275 70 720 1050<br />
40 c 20 25 20 30 30 20 20<br />
— 50/50 50/50 50/50 50/50 25/75 50/50 50/50<br />
1000 350 400 171 184 340 170 500<br />
3
table 2<br />
4<br />
Applications & Characteristics<br />
Applications<br />
Packaging General Marine & Magnetic Strippable Wood<br />
Food Non-Food Metals Maintenance Media Inks Adhesives Coatings Finishes<br />
VYNS-3 ■ ■ ■ ■ ■ ■<br />
VYHH ■ ■ ■ ■ ■ ■<br />
VYHD ■ ■ ■ ■<br />
VMCH ■ ■ ■ ■ ■<br />
VMCC ■ ■ ■ ■ ■<br />
VMCA ■ ■ ■ ■ ■<br />
VERR-40 ■<br />
VAGH ■ ■ ■ ■ ■ ■ ■<br />
VAGD ■ ■ ■ ■ ■<br />
VAGF ■ ■ ■ ■ ■ ■ ■<br />
VAGC ■ ■ ■ ■ ■ ■<br />
VROH ■ ■ ■ ■<br />
UCARMAG®<br />
Binder<br />
527 ■<br />
569 ■<br />
table 3<br />
General Characteristics of UCAR® Solution <strong>Vinyl</strong> <strong>Resins</strong><br />
Appearance* White powder<br />
Particle Size<br />
% by wt, min, through 20 mesh 98<br />
Bulk Density, lb/ft 3 24 to 34<br />
Heat Loss, % by wt, max 3.0<br />
Water Content, % by wt, max 0.5<br />
Melting Point, ºC 93 to 135<br />
*VERR-40 is a solution
FDA Status<br />
The UCAR® Solution <strong>Vinyl</strong> <strong>Resins</strong> listed below are cited in the<br />
following regulations 1 of the United States Food and Drug<br />
Administration (FDA) for use in food-contact applications, such<br />
as can, paper, film, and foil coatings, and coatings for closures.<br />
FDA Regulation Use UCAR® Solution <strong>Vinyl</strong> Resin<br />
21CFR 175.105 Components of adhesives used in articles intended VYHD, VYHH, VYNS-3,<br />
for packaging, transporting or holding food. VMCA, VMCC, VMCH,<br />
VAGD, VAGH, VERR-40<br />
21CFR 175.300 Components of resinous and polymeric coatings VYHD, VYHH, VYNS-3,<br />
to be applied as continuous films to food-contact VMCA, VMCC, VMCH,<br />
surfaces of articles intended for use in processing, VAGD, VAGH, VERR-40<br />
manufacturing, packing, producing, heating,<br />
packaging, holding, or transporting food.<br />
21CFR 175.320 Components of a coating that is applied as a VYHD, VYHH, VYNS-3,<br />
continuous film over one or both sides of a base VMCA, VMCC, VMCH,<br />
film produced from one or more of the basic olefin VAGD, VAGH<br />
polymers complying with 177.1520.<br />
21CFR 176.170 Components of the food-contact surface of paper VYHD, VYHH, VYNS-3,<br />
and paperboard used to package aqueous and VMCA, VMCC, VMCH,<br />
fatty foods. VAGD, VAGH<br />
21CFR 176.180 Components of paper and paperboard in contact VYHD, VYHH, VYNS-3,<br />
with dry food. VMCA, VMCC, VMCH,<br />
VAGD, VAGH, VERR-40<br />
21CFR 177.1210 Components of closures with sealing gaskets VYHD, VYHH, VYNS-3,<br />
for food containers. VMCA, VMCC, VMCH,<br />
VAGD, VAGH, VERR-40<br />
(1) Since government regulations are subject to revision, it is the user’s responsibility to refer to the Code of Federal Regulations<br />
or the Federal Register to determine current regulatory status.<br />
5
6<br />
<strong>Vinyl</strong> Chloride/<strong>Vinyl</strong> Acetate Copolymers<br />
VYNS-3<br />
The highest molecular weight solution vinyl resin, having<br />
a composition of approximately 90 percent vinyl chloride<br />
and 10 percent vinyl acetate. UCAR® Solution <strong>Vinyl</strong> Resin<br />
VYNS-3 is usually dissolved in relatively strong ketone<br />
systems to provide resin solutions of 13 to 17 percent<br />
solids. VYNS-3 is used where the ultimate toughness,<br />
durability, and chemical resistance are required. Because<br />
of its excellent tensile tear properties, VYNS-3 is ideally<br />
suited for strippable coatings applications. VYHH is often<br />
blended with VYNS-3 to increase sprayable solids.<br />
VYHH<br />
A high molecular weight resin having a composition of<br />
approximately 86 percent vinyl chloride and 14 percent<br />
vinyl acetate. VYHH offers a desirable balance of chemical<br />
resistance, solubility, film strength, and thermoplasticity.<br />
VYHH is usually dissolved in a relatively strong<br />
solvent/diluent combination, such as ketone solvent/<br />
aromatic diluent (50/50 percent by weight). With this<br />
system, a solids content of 20 to 22 percent can be<br />
achieved. Marine and maintenance coatings, ink and<br />
overlacquers for vinyl substrates, strippable coatings,<br />
and masonry and metal coatings are among the principal<br />
applications for UCAR Solution <strong>Vinyl</strong> Resin VYHH.<br />
VYHD<br />
A medium molecular weight resin having a composition<br />
of approximately 86 percent vinyl chloride and 14 percent<br />
vinyl acetate. UCAR Solution <strong>Vinyl</strong> Resin VYHD is more<br />
soluble in ketones and other solvents than VYHH and,<br />
therefore, has a greater tolerance for aromatic hydrocarbon<br />
diluents. Resin solutions of 25 percent solids can be<br />
achieved by dissolving VYHD in a system consisting<br />
of ketone solvent/aromatic diluent (35/65 percent by<br />
weight). VYHD can be substituted for VYHH in most<br />
applications where higher solids are needed.
Carboxyl-Modified<br />
<strong>Vinyl</strong> Chloride/<strong>Vinyl</strong> Acetate Copolymers<br />
The carboxyl-modified vinyl chloride/vinyl acetate<br />
copolymers are made specifically for the formulation of<br />
coatings having excellent adhesion to various substrates,<br />
especially metals, cellulosics, and certain plastics.<br />
VMCH<br />
A high molecular weight resin containing approximately<br />
86 percent vinyl chloride, 13 percent vinyl acetate, and<br />
1 percent maleic acid. UCAR® Solution <strong>Vinyl</strong> Resin VMCH<br />
is usually dissolved in relatively strong solvent/diluent<br />
combinations, such as 50 percent ketone/50 percent<br />
aromatic hydrocarbon, to produce solutions of 20 to 22<br />
percent solids. UCAR Solution <strong>Vinyl</strong> Resin VMCH is used<br />
primarily for air-dry finishes, such as maintenance,<br />
marine, and metal coatings. VMCH is often used to<br />
make heat-sealable packaging coatings.<br />
VMCC<br />
A medium molecular weight resin containing approximately<br />
83 percent vinyl chloride, 16 percent vinyl acetate,<br />
and 1 percent maleic acid. UCAR Solution <strong>Vinyl</strong> Resin<br />
VMCC is more soluble than VMCH in ketones, esters, and<br />
other solvents used to dissolve vinyl resins. VMCC also has<br />
a higher tolerance for aromatic hydrocarbon diluents.<br />
VERR-40<br />
A low molecular weight epoxy-modified copolymer<br />
available only as a solution at 40 percent solids in<br />
MEK/toluene (3/2 by weight). VERR-40 can be blended<br />
with carboxyl-modified vinyls (VMCH, VMCC, and VMCA)<br />
to provide an all-vinyl reactive coating system that,<br />
when cured by baking, yields coatings with enhanced<br />
toughness, flexibility, and solvent resistance.<br />
When dissolved in a suitable solvent system, such as a<br />
50 percent ketone/50 percent aromatic hydrocarbon,<br />
resin solutions of 23 to 25 percent solids can be achieved.<br />
VMCC is often used in the same applications as VMCH.<br />
However, because of its better solubility, it also finds<br />
use as an adhesion promoter for vinyl organosols in<br />
can coatings.<br />
VMCA<br />
A low molecular weight resin containing approximately<br />
81 percent vinyl chloride, 17 percent vinyl acetate, and<br />
2 percent maleic acid. UCAR Solution <strong>Vinyl</strong> Resin VMCA<br />
is characterized by a high degree of solubility in solvent<br />
systems having a high aromatic hydrocarbon content.<br />
When dissolved in a suitable solvent/diluent combination,<br />
such as 25 percent ketone/75 percent aromatic hydrocarbon,<br />
resin solutions of 30 percent solids can be<br />
achieved. VMCA yields the good balance of solubility<br />
and viscosity properties needed for high-build, air-dry<br />
maintenance finishes. VMCA can also be used in coatings<br />
and adhesives applications where higher solids are<br />
desirable.<br />
Epoxy-Modified<br />
<strong>Vinyl</strong> Chloride/<strong>Vinyl</strong> Acetate Copolymers<br />
7
8<br />
Hydroxyl-Modified<br />
<strong>Vinyl</strong> Chloride/<strong>Vinyl</strong> Acetate Copolymers<br />
UCAR® Hydroxyl-Modified <strong>Vinyl</strong> Chloride/<strong>Vinyl</strong> Acetate<br />
Copolymers are manufactured using two different processes.<br />
VAGH and VAGD are polymers made in a two-step process<br />
that yields vinyl alcohol in the backbone. The other<br />
hydroxyl-modified resins are produced by a one-step<br />
polymerization process similar to that used to make the<br />
copolymer and carboxy-functional solution polymerized<br />
resins described above.<br />
Hydroxyl-modified vinyl chloride/vinyl acetate copolymers<br />
are noted particularly for compatibility with other filmforming<br />
resins, such as alkyds, urethane elastomers,<br />
isocyanate resins, epoxy polymers, and urea and melamine<br />
resins. Hydroxyl-modified vinyls are, therefore, often<br />
formulated with these and other film-forming materials<br />
to improve coating properties, such as adhesion, flexibility,<br />
toughness, hardness, and chemical resistance. Hydroxylmodified<br />
resins are often used to impart snap-dry properties<br />
to a coating. The hydroxyl functionality permits crosslinking<br />
reactions for thermoset coating systems that exhibit<br />
outstanding chemical and water resistance. Coatings based<br />
on these resins also have good adhesion to wash primers,<br />
metals, wood, and many plastic substrates.<br />
■ HYDROLYZED RESINS<br />
VAGH<br />
A high molecular weight, partially-hydrolyzed vinyl chloride/vinyl<br />
acetate resin having a composition of approximately<br />
90 percent vinyl chloride, 4 percent vinyl acetate,<br />
with a hydroxyl content of approximately 2.3 percent. UCAR<br />
Solution <strong>Vinyl</strong> Resin VAGH can be dissolved in relatively<br />
strong solvent/diluent combinations, such as 50 percent<br />
ketone/50 percent aromatic hydrocarbon, to produce resin<br />
solutions of 20 percent solids. VAGH can be used for a<br />
wide range of coatings applications, including industrial<br />
maintenance and marine finishes, wood finishes, paper<br />
coatings, metal decorative and container coatings, and<br />
as a binder in magnetic tape.<br />
VAGD<br />
A medium molecular weight, partially-hydrolyzed vinyl<br />
chloride/vinyl acetate resin having a composition of approximately<br />
90 percent vinyl chloride, 4 percent vinyl acetate,<br />
with a hydroxyl content of approximately 2.3 percent.<br />
The lower molecular weight provides improved solubility<br />
and permits the formulation of solutions containing<br />
higher solids.<br />
■ DIRECTLY-POLYMERIZED RESINS<br />
VAGF<br />
A high molecular weight copolymer comprised of vinyl<br />
chloride, vinyl acetate, and a hydroxyalkyl acrylate. The vinyl<br />
chloride portion is about 81 percent with the hydroxyl content<br />
at 1.8 percent. The solution viscosity and other properties of<br />
VAGF strongly resemble those of VAGH. VAGF can be used for<br />
a wide range of coatings applications, including industrial<br />
maintenance and marine finishes, paper coatings, general<br />
metal finishes, and as a binder in magnetic tape.<br />
VAGC<br />
A medium molecular weight copolymer comprised of vinyl<br />
chloride, vinyl acetate, and a hydroxyalkyl acrylate. The<br />
vinyl chloride portion is about 81 percent with the hydroxyl<br />
content at 1.9 percent. The solution viscosity and other<br />
properties of VAGC are very similar to those of VAGD.<br />
VAGC finds commercial application in clear and pigmented<br />
coatings for metal, wood, paper, concrete, masonry, films,<br />
foils, fabrics, and leather.<br />
VROH<br />
A low molecular weight terpolymer comprised of vinyl<br />
chloride, vinyl acetate, and a hydroxyalkyl acrylate. The<br />
vinyl chloride portion is approximately 81 percent, and the<br />
hydroxyl content is approximately 2 percent. High tolerance<br />
for alcohols and aliphatic diluents broadens the usefulness<br />
of VROH. UCAR Solution <strong>Vinyl</strong> Resin VROH can be dissolved<br />
in solvent/diluent combinations, such as 25 percent<br />
ketone/75 percent aromatic hydrocarbon, to produce resin<br />
solutions of 30 percent solids. Also, 35 percent resin solutions<br />
can be prepared with VROH using Rule 66-type exempt<br />
solvent systems (for the wood coatings industry) containing<br />
as much as 30 percent by volume butanol. UCAR Solution<br />
<strong>Vinyl</strong> Resin VROH can be used in a wide variety of clear<br />
and pigmented coatings for metal, wood, paper, film, foil,<br />
and fabric.
UCARMAG® Binder 527<br />
A high molecular weight copolymer comprised of vinyl<br />
chloride, vinyl acetate, a hydroxy-alkyl acrylate and a<br />
carboxylated monomer. The vinyl chloride content is<br />
about 80 percent by weight and the hydroxyl content is<br />
about 1.8 percent. The molecular weight and physical<br />
properties of UCARMAG Binder 527 are similar to those<br />
of VAGF. A carboxyl monomer in the UCARMAG Binder 527<br />
gives the terpolymer excellent wetting and pigment<br />
dispersion properties and has made the resin especially<br />
useful in magnetic tape coatings containing neutral<br />
or basic pigments. Because of its unique functionality,<br />
UCARMAG 527 might also be considered as a binder for<br />
printing inks, paper coatings and general metal finishes.<br />
UCARMAG® Binder 569<br />
A medium molecular weight terpolymer containing<br />
vinyl chloride, vinyl acetate and a monomer with metal<br />
sulfonate functionality. The vinyl chloride of the terpolymer<br />
is about 85 percent by weight. The sulfonate functional<br />
monomer provides the terpolymer with exceptional wetting<br />
characteristics which make it an excellent dispersing<br />
medium for high surface area pigments used in magnetic<br />
media applications. Since the terpolymer has excellent<br />
Solutions<br />
Several criteria must be weighed in choosing solvents<br />
and diluents for UCAR Solution <strong>Vinyl</strong> <strong>Resins</strong>:<br />
■ Solvent Strength<br />
■ Volatility<br />
■ Toxicity<br />
■ Odor<br />
■ Cost<br />
■ Flammability<br />
■ Type of Application<br />
UCAR Solution <strong>Vinyl</strong> <strong>Resins</strong> are readily dissolved<br />
into clear solutions at room temperature by ketones,<br />
nitroparaffins, esters, and chlorinated hydrocarbons.<br />
heat stability, it can be used in applications requiring<br />
high shear milling operations to disperse high surface<br />
area or highly porous pigments. UCARMAG Binder 569,<br />
because of its sulfonate functionality, may also be useful<br />
in other non-magnetic media applications where good<br />
dispersing capabilities are needed.<br />
Solution <strong>Vinyl</strong> <strong>Resins</strong> for<br />
VOC-Compliant Coatings<br />
Since their commercialization about 50 years ago,<br />
UCAR® Solution-Polymerized <strong>Vinyl</strong> <strong>Resins</strong> have become<br />
the standards for a wide range of coatings applications.<br />
UCAR Waterborne <strong>Vinyl</strong> Resin Dispersions have been<br />
developed for compliant waterborne coatings, adhesives,<br />
and inks. These waterborne resin dispersions utilize a<br />
solution-polymerized vinyl resin backbone that has been<br />
chemically modified to allow dispersion in water.<br />
In general, ketones are the most suitable solvents<br />
for vinyl resins. Compared to other solvents, ketones<br />
yield higher resin concentrations without gelling and<br />
lower solution viscosities at equivalent solids content.<br />
Because of their solvency, they tolerate greater dilution<br />
with economical hydrocarbon diluents and exhibit<br />
better storage stability. Figure 1 compares the solvent<br />
strength of different ketones for VYHD.<br />
Esters are useful in applications where minimal<br />
attack on the substrate is desirable (as with coatings on<br />
plastics). Because of their low solvency for vinyls, they<br />
should be used in combination with other active solvents.<br />
Urethane-grade esters are preferred for minimum<br />
viscosity and optimum viscosity stability. Figure 2 compares<br />
the solvent strength of different esters for VYHD.<br />
9
figure 1<br />
10<br />
Viscosity vs. Concentration of VYHD in Ketones<br />
Viscosity at 25ºC, cP<br />
10,000<br />
8,000<br />
6,000<br />
5,000<br />
4,000<br />
3,000<br />
2,000<br />
1,000<br />
800<br />
600<br />
500<br />
400<br />
300<br />
200<br />
100<br />
80<br />
60<br />
50<br />
40<br />
30<br />
20<br />
10<br />
Isophorone<br />
Cyclohexanone<br />
Methyl Isobutyl Ketone<br />
Methyl Ethyl Ketone<br />
Acetone<br />
0 10 20 30 40<br />
50<br />
Solids, percentage by weight<br />
NOTE: Viscosity was determined using a Brookfield viscometer model RVT, running at 50 or 100 rpm with spindles<br />
#2 through #5, selected as appropriate for the solution being tested.
Viscosity vs. Concentration of VYHD in Esters<br />
Viscosity at 25ºC, cP<br />
10,000<br />
8,000<br />
6,000<br />
5,000<br />
4,000<br />
3,000<br />
2,000<br />
1,000<br />
800<br />
600<br />
500<br />
400<br />
300<br />
200<br />
100<br />
80<br />
60<br />
50<br />
40<br />
30<br />
20<br />
10<br />
Methyl PROPASOL® Acetate<br />
Isopropyl Acetate<br />
Butyl Acetate<br />
Ethyl Acetate<br />
0 5 10 15 20 25 30 35<br />
Solids, percentage by weight<br />
NOTE: Viscosity was determined using a Brookfield viscometer model RVT, running at 50 or 100 rpm with spindles<br />
#2 through #5, selected as appropriate for the solution being tested.<br />
figure 2<br />
11
12<br />
Solution Viscosity of VYHH in Ketones and Ketone/Aromatic Blends<br />
table 4<br />
Solution Viscosity at 25ºC, cP<br />
Ketone Solvent Formula A Formula B<br />
Acetone 84 88<br />
Methyl Ethyl Ketone 86 130<br />
Methyl Propyl Ketone 124 212<br />
Methyl Isobutyl Ketone 230 360<br />
Methyl Isoamyl Ketone 304 504<br />
Methyl n-Amyl Ketone 316 684<br />
Cyclohexanone 672 360<br />
Isophorone 930 484<br />
Formulation Formula A Formula B<br />
UCAR® Solution <strong>Vinyl</strong> VYHH 20 20<br />
Ketone Solvent 80 40<br />
Xylene — 20<br />
Toluene — 20<br />
Diluents lower coating costs, alter the evaporation rates,<br />
and provide other important coating characteristics.<br />
Typical diluents for use with UCAR® Solution <strong>Vinyl</strong> <strong>Resins</strong><br />
include aromatic hydrocarbons, such as toluene and<br />
xylene. Aliphatic hydrocarbons, such as mineral spirits,<br />
VM&P naphtha, and heptane, can also be used. These<br />
aliphatic hydrocarbons are less effective than aromatic<br />
hydrocarbons and should be used at levels not<br />
exceeding 10 percent of the solvent blend.<br />
Ketones tolerate greater amounts of aromatic<br />
diluents than do the ester solvents. Table 4 compares<br />
the viscosity of VYHH in ketones with the viscosity in<br />
ketone/diluent mixtures.<br />
Parts by Weight 100 100<br />
NOTE: Viscosity was determined using a Brookfield viscometer model RVT, running at 50 or 100 rpm with spindles<br />
#2 through #5, selected as appropriate for the solution being tested.<br />
Optimum formulation stability and the lowest<br />
solution viscosities are obtained when the solvent system<br />
contains only active solvents. As the proportion of diluent<br />
increases, the stability declines. Figures 3 to 5 compare<br />
the solution viscosity of UCAR Solution <strong>Vinyl</strong> <strong>Resins</strong><br />
versus solids content in methyl ethyl ketone and in<br />
a methyl isobutyl ketone/toluene (50/50) blend.<br />
Formulating at excessively high solids or with weak<br />
solvent mixtures can result in solutions having unstable<br />
viscosities and can even lead to the formation of gel<br />
structures. As the molecular weight of the vinyl resin<br />
decreases, however, the diluent level can be increased<br />
while maintaining the same level of viscosity.
Viscosity vs. Concentration of <strong>Vinyl</strong> Chloride/<strong>Vinyl</strong> Acetate Copolymers<br />
in Methyl Ethyl Ketone<br />
Viscosity at 25ºC, cP<br />
10,000<br />
8,000<br />
6,000<br />
5,000<br />
4,000<br />
3,000<br />
2,000<br />
1,000<br />
800<br />
600<br />
500<br />
400<br />
300<br />
200<br />
100<br />
80<br />
60<br />
50<br />
40<br />
30<br />
20<br />
10<br />
VYNS-3<br />
VYHH<br />
VYHD<br />
0 10 20 30 40<br />
50<br />
Solids, percentage by weight<br />
NOTE: Viscosity was determined using a Brookfield viscometer model RVT, running at 50 or 100 rpm with spindles<br />
#2 through #5, selected as appropriate for the solution being tested.<br />
figure 3<br />
13
figure 3a<br />
14<br />
Viscosity vs. Concentration of <strong>Vinyl</strong> Chloride/<strong>Vinyl</strong> Acetate Copolymers<br />
in Methyl Isobutyl Ketone/Toluene (50/50)<br />
Viscosity at 25ºC, cP<br />
10,000<br />
8,000<br />
6,000<br />
5,000<br />
4,000<br />
3,000<br />
2,000<br />
1,000<br />
800<br />
600<br />
500<br />
400<br />
300<br />
200<br />
100<br />
80<br />
60<br />
50<br />
40<br />
30<br />
20<br />
10<br />
VYNS-3<br />
VYHH<br />
VYHD<br />
0 10 20 30 40<br />
50<br />
Solids, percentage by weight<br />
NOTE: Viscosity was determined using a Brookfield viscometer model RVT, running at 50 or 100 rpm with spindles<br />
#2 through #5, selected as appropriate for the solution being tested.
Viscosity vs. Concentration of Hydroxyl-Modified Copolymers<br />
in Methyl Ethyl Ketone<br />
Viscosity at 25ºC, cP<br />
10,000<br />
8,000<br />
6,000<br />
5,000<br />
4,000<br />
3,000<br />
2,000<br />
1,000<br />
800<br />
600<br />
500<br />
400<br />
300<br />
200<br />
100<br />
80<br />
60<br />
50<br />
40<br />
30<br />
20<br />
10<br />
0<br />
VAGH<br />
VAGF<br />
VAGD<br />
VAGC<br />
VROH<br />
10 20 30 40<br />
50<br />
Solids, percentage by weight<br />
NOTE: Viscosity was determined using a Brookfield viscometer model RVT, running at 50 or 100 rpm with spindles<br />
#2 through #5, selected as appropriate for the solution being tested.<br />
figure 4<br />
15
figure 4a<br />
16<br />
Viscosity vs. Concentration of Hydroxyl-Modified Copolymers<br />
in Methyl Isobutyl Ketone/Toluene (50/50)<br />
Viscosity at 25ºC, cP<br />
10,000<br />
8,000<br />
6,000<br />
5,000<br />
4,000<br />
3,000<br />
2,000<br />
1,000<br />
800<br />
600<br />
500<br />
400<br />
300<br />
200<br />
100<br />
80<br />
60<br />
50<br />
40<br />
30<br />
20<br />
10<br />
0<br />
VAGH<br />
VAGF<br />
VAGD<br />
VAGC<br />
VROH<br />
10 20 30 40<br />
50<br />
Solids, percentage by weight<br />
NOTE: Viscosity was determined using a Brookfield viscometer model RVT, running at 50 or 100 rpm with spindles<br />
#2 through #5, selected as appropriate for the solution being tested.
Viscosity vs. Concentration of Carboxyl-Modified Copolymers<br />
in Methyl Ethyl Ketone<br />
Viscosity at 25ºC, cP<br />
10,000<br />
8,000<br />
6,000<br />
5,000<br />
4,000<br />
3,000<br />
2,000<br />
1,000<br />
800<br />
600<br />
500<br />
400<br />
300<br />
200<br />
100<br />
80<br />
60<br />
50<br />
40<br />
30<br />
20<br />
10<br />
VMCH<br />
VMCC<br />
VMCA<br />
0 10 20 30 40<br />
50<br />
Solids, percentage by weight<br />
NOTE: Viscosity was determined using a Brookfield viscometer model RVT, running at 50 or 100 rpm with spindles<br />
#2 through #5, selected as appropriate for the solution being tested.<br />
figure 5<br />
17
figure 5a<br />
18<br />
Viscosity vs. Concentration of Carboxyl-Modified Copolymers<br />
in Methyl Isobutyl Ketone/Toluene (50/50)<br />
Viscosity at 25ºC, cP<br />
10,000<br />
8,000<br />
6,000<br />
5,000<br />
4,000<br />
3,000<br />
2,000<br />
1,000<br />
800<br />
600<br />
500<br />
400<br />
300<br />
200<br />
100<br />
80<br />
60<br />
50<br />
40<br />
30<br />
20<br />
10<br />
VMCH<br />
VMCC<br />
VMCA<br />
0 10 20 30 40<br />
50<br />
Solids, percentage by weight<br />
NOTE: Viscosity was determined using a Brookfield viscometer model RVT, running at 50 or 100 rpm with spindles<br />
#2 through #5, selected as appropriate for the solution being tested.
Memory Effect of <strong>Vinyl</strong> Resin Solutions<br />
Viscosity<br />
0<br />
Cooled<br />
Room Temperature<br />
Heated<br />
■ VISCOSITY BEHAVIOR<br />
1 2 3 4<br />
5<br />
Time (weeks)<br />
Viscosity behavior of vinyl solutions is influenced by resin<br />
concentration, active solvent used, ratio of solvent to<br />
diluent, and solution temperature.<br />
Viscosity changes in vinyl solutions are the result<br />
of different equilibrium effects that occur during the<br />
preparation and storage of resin solutions. The formation<br />
of a slight degree of micro-crystallinity among adjacent<br />
polymer molecules in solution is responsible for the<br />
observed viscosity increase.<br />
The time required to reach equilibrium viscosity<br />
for vinyl resin solutions is influenced by resin molecular<br />
weight, solids content, solvent strength, processing time,<br />
and temperature. <strong>Vinyl</strong> resin solutions usually increase<br />
in viscosity with time. The extent of the total increase can<br />
range from a minor viscosity drift to a major change, such<br />
as gelation. <strong>Vinyl</strong> solutions that have gelled because of<br />
excessive solids content or a solvent mix that is too weak<br />
can be restored to fluidity by proper thinning and mixing.<br />
Another equilibrium condition that affects solution<br />
viscosity is the memory effect. It is noted in vinyl solutions<br />
that have been subjected to increases or decreases in<br />
temperature and is characterized by a significant lag in<br />
the rate at which a vinyl solution returns to equilibrium<br />
viscosity after a temperature change. For example, a vinyl<br />
solution that has been heated will maintain an abnormally<br />
low viscosity for extended periods after it has returned to<br />
its initial temperature. This viscosity change is caused by<br />
differences in the degree of microcrystallinity of the solution<br />
at various temperatures. As the temperature increases, the<br />
degree of microcrystalline regions that exist in the solution<br />
decreases and the viscosity decreases. The memory effect<br />
is illustrated in Figure 6.<br />
Formulators must be aware of both these effects and<br />
the time required to reach equilibrium conditions, so that<br />
viscosity stability problems, resulting from the preparation<br />
of solutions at incorrect solids levels or solvent blends,<br />
are avoided.<br />
figure 6<br />
19
20<br />
■ APPLICATION METHODS<br />
Coatings based on UCAR® Solution <strong>Vinyl</strong> <strong>Resins</strong> may be<br />
readily applied by commonly used application methods,<br />
such as brushing, spraying, dipping, and roller coating.<br />
Of major consideration for all applications is the correct<br />
consistency of the coating and proper evaporation rate<br />
of the solvent used in a particular application method.<br />
Table 5 shows the properties of solvents useful with<br />
UCAR Solution <strong>Vinyl</strong> <strong>Resins</strong>.<br />
Paper and cloth coatings may be formulated with<br />
highly volatile solvents, such as acetone and methyl<br />
ethyl ketone. Application by roller coaters requires<br />
solvents and diluents with a slow evaporation rate.<br />
Isophorone is used for roller coating because it is an<br />
excellent solvent for vinyls and has a slow evaporation<br />
rate. Methyl PROPASOL® Acetate and cyclohexanone<br />
are used for brush applications because they are slowevaporating<br />
solvents that promote ease of application<br />
and good flow-out.<br />
■ SOLUTION PREPARATION<br />
Use a high-shear mixer to prepare solutions of UCAR<br />
Solution <strong>Vinyl</strong> <strong>Resins</strong>. Slow-speed, paddle-type agitators<br />
are not as effective as high-shear mixers. Equip the<br />
mixers with tight-fitting covers.<br />
Add the solvent/diluent mixtures to the high-shear<br />
mixer. As the solvent mixture is agitated, add the resin<br />
slowly. The resin must be added slowly or lumping may<br />
occur.<br />
As an alternate procedure, slurry the vinyl resin<br />
in a solvent/diluent blend containing about 20 percent<br />
of active solvent. Add the resin slowly. When all the resin<br />
is thoroughly wetted, vigorously agitate the slurry and<br />
slowly add the remaining portion of the active solvent.<br />
Do not slurry the vinyl resin in the diluent alone;<br />
slurrying with diluents may produce a static electrical<br />
discharge and cause a flash fire.<br />
Follow all precautions for the safe handling of<br />
organic solvents and diluents.<br />
High-shear mixing will heat solutions, especially<br />
viscous solutions. Maintain the solution temperature<br />
as low as possible. If solutions are held at elevated<br />
temperatures for long periods of time, discoloration<br />
may result.<br />
The addition of about 1.0 to 2.0 percent UNION<br />
CARBIDE Cycloaliphatic Epoxide ERL-4221* on resin will<br />
help control discoloration without affecting coating<br />
performance. For maximum stability, vinyl resin solutions<br />
should be stored in baked phenolic-lined containers.<br />
*Note: Union Carbide’s Cycloaliphatic Epoxide ERL-4221 has no<br />
United States Food and Drug Administration (FDA) clearances for<br />
use in food-contact applications.
Solvents for UCAR® Solution <strong>Vinyl</strong> <strong>Resins</strong><br />
. Relative<br />
Evaporation Weight Flash Point,<br />
Rate Solubility per gallon Distillation Closed<br />
Solvents (BuAc=100) with VYHH a,b at 20ºC, lb Range, ºC Cup, ºF<br />
Fast Evaporating<br />
Acetone 1160 S 6.59 56-57 0<br />
Ethyl Acetate, 99% 615 S 7.51 76-78 30<br />
Methyl Ethyl Ketone 570 S 6.71 78-81 24<br />
Isopropyl Acetate, 99% 500 S-G 7.26 86-90 42<br />
Propyl Acetate 275 S 7.39 99-103 58<br />
Medium Evaporating<br />
Methyl Isobutyl Ketone 165 S 6.67 114-117 61<br />
Isobutyl Acetate, Urethane Grade 145 S 7.25 112-117 62<br />
Butyl Acetate, Urethane Grade 100 S 7.34 124-129 84<br />
Slow Evaporating<br />
Amyl Acetate, Primary 42 S 7.29 140-150 101<br />
Cyclohexanone 23 S 7.89 156 111<br />
Methyl PROPASOL® Acetate 34 S 8.09 146 114<br />
Diisobutyl Ketone 18 S-G 6.72 163-173 120<br />
Diacetone Alcohol 14 S 7.82 145-172 133<br />
Isophorone 3 S 7.67 210-218 179<br />
(a) 0.5g VYHH to 4.5ml solvent<br />
(b) S=Soluble<br />
S-G= Soluble, tendency to gel<br />
table 5<br />
21
22<br />
Formulation of Clear Coatings<br />
Clear vinyl coatings can be modified with plasticizers,<br />
heat and light stabilizers, and other materials for specific<br />
performance properties. Before incorporating any modifier<br />
in the formulation, understand clearly how the modifier<br />
meets the demands of the application. Do not use clear<br />
vinyl coatings for applications that involve long-term<br />
exposure to ultraviolet light.<br />
Plasticizers<br />
The addition of a plasticizer in the coating formulation<br />
will enhance flexibility and help to minimize solvent<br />
retention in the film. The typical phthalate, adipate,<br />
citrate, epoxy, and phosphate plasticizers are compatible<br />
with UCAR® Solution <strong>Vinyl</strong> <strong>Resins</strong>. In general, compatibility<br />
decreases as the hydrocarbon nature of the plasticizer<br />
increases. Polymeric plasticizers are less efficient than<br />
monomeric plasticizers.<br />
Other factors to consider in selecting plasticizers<br />
include solubility, volatility, the effect on outdoor durability,<br />
the need for low-temperature flexibility, and suitability<br />
for contact with food. Certain citrates, epoxies, and<br />
phthalates are permitted under FDA regulations.<br />
Monomeric plasticizers are most commonly used,<br />
although the polymeric plasticizers are used to provide<br />
special film characteristics, such as low extractability<br />
or migration. Phosphate plasticizers are generally not<br />
recommended for outdoor exposure because of poor<br />
light stability.<br />
When a bake cycle is required, the volatility of the<br />
plasticizer is particularly important. The plasticizer may<br />
volatilize sufficiently to lower the concentration below<br />
what was originally intended for the dried or cured<br />
formulation.<br />
The optimum level of plasticizer for a formulation<br />
will depend upon the specific resin used and the performance<br />
property required by the application. To obtain<br />
equivalent degrees of flexibility, higher molecular weight<br />
resins require more plasticizer than lower molecular<br />
weight resins. Proportions of 10 to 25 parts plasticizer<br />
per 100 parts of resin are typically used.<br />
Table 6 provides a list of plasticizers having good<br />
compatibility with UCAR Solution <strong>Vinyl</strong> <strong>Resins</strong>.<br />
Heat Stabilizers<br />
As with all vinyl resins, UCAR Solution <strong>Vinyl</strong> <strong>Resins</strong><br />
are degraded upon prolonged exposure to heat. The<br />
degradation products include hydrogen chloride, which<br />
accelerates further resin degradation and leads to the<br />
development of unsaturated polymer structures that can<br />
be easily oxidized. The result is embrittlement, loss of<br />
flexibility, and discoloration of the vinyl film. To minimize<br />
the degradation of vinyl films, add suitable heat stabilizers.<br />
Baking at temperatures above 248ºF (120ºC) for more<br />
than five minutes will usually require a thermal<br />
stabilizer to avoid degradation of the film. The use of<br />
a tin mercaptide stabilizer (1 percent*) in combination<br />
with a liquid epoxy resin, such as ERL-4221, or diglycidyl<br />
ether of bisphenol A resin (3 to 5 percent*) gives the<br />
best results.<br />
Do not use barium, cadmium, or zinc stabilizers with<br />
the carboxyl-modified vinyl resins; they tend to react with<br />
the carboxyl groups. Zinc stabilizers also tend to develop<br />
color quickly, especially in low plasticizer systems. Iron<br />
and zinc surfaces can accelerate decomposition and<br />
discoloration.<br />
*on weight of vinyl resin
Light Stabilizers<br />
An adequate quantity of a hiding pigment will screen out<br />
incident radiation and prove the best light stabilizer for<br />
pigmented vinyl coatings. Do not use unpigmented vinyl<br />
coatings outdoors. Where only limited ultraviolet light<br />
exposure will be encountered, clear films should be formulated<br />
with a light stabilizer system to prevent discoloration.<br />
The best light stabilizer system includes an ultraviolet light<br />
absorber (substituted benzophenones), a hindered amine<br />
light stabilizer (HALS), and UNION CARBIDE ERL-4221,<br />
a cycloaliphatic epoxy resin.<br />
A typical system would be comprised of the following:<br />
Ingredients %*<br />
UV Absorber 1 1<br />
HALS 2 2<br />
ERL-4221 3 3<br />
* on weight of vinyl resin<br />
(1) UV Absorber - “Uvinul” D-5O (BASF), “Tinuvin” 327<br />
or 328 (Ciba Geigy) or equivalent.<br />
(2) HALS - “Tinuvin” 292 (Ciba Geigy) or equivalent.<br />
(3) Cycloaliphatic Epoxide (Union Carbide).<br />
In all cases, choose stabilizers carefully and test them<br />
under actual use conditions. Consult suppliers of stabilizers<br />
for specific recommendations.<br />
Typical Plasticizers for<br />
UCAR® Solution <strong>Vinyl</strong> <strong>Resins</strong><br />
Type Product<br />
Phthalate Diisooctyl Phthalate<br />
Diisodecyl Phthalate<br />
Butyl Benzyl Phthalate<br />
Butyl 2-Ethylhexyl Phthalate<br />
2-Ethylhexyl Isodecyl Phthalate<br />
Citrate Acetyl Tributyl Citrate<br />
Acetyl Triethyl Citrate<br />
Tributyl Citrate<br />
Phosphate Tri(2-ethylhexyl) Phosphate<br />
Triphenyl Phosphate<br />
Tributyl Phosphate<br />
Epoxy FLEXOL® Plasticizer EPO<br />
(Epoxidized soybean oil)<br />
FLEXOL® Plasticizer EP-8<br />
(2-Ethylhexyl epoxy tallate)<br />
FLEXOL® Plasticizer LOE<br />
(Epoxidized linseed oil)<br />
Polymeric Adipic Acid Polyester<br />
Azelaic Acid Polyester<br />
Sebacic Acid Polyester<br />
Blown Castor Oil<br />
Blown Soybean Oil<br />
Blown Linseed Oil<br />
Miscellaneous Dibutyl Sebacate<br />
Di(2-ethylhexyl) Sebacate<br />
Di(2-ethylhexyl) Azelate<br />
table 6<br />
23
24<br />
Formulation of Pigmented Coatings<br />
Pigments are selected for hiding power, ultraviolet<br />
protection, purity, and ease of wetting. Although most<br />
commercially-available pigments are suitable for use<br />
with UCAR® Solution <strong>Vinyl</strong> <strong>Resins</strong>, there are some general<br />
constraints. Additionally, there are specific constraints that<br />
apply to UCAR Carboxyl-Modified Solution <strong>Vinyl</strong> <strong>Resins</strong>.<br />
Do not use natural iron oxide pigments with any<br />
UCAR Solution <strong>Vinyl</strong> Resin. These pigments contain trace<br />
impurities that can gel the coating or cause discoloration<br />
or excessive chalking of the film. Do not use ironcontaining<br />
pigments, such as Prussian blue or the socalled<br />
“chrome greens” (blends of Prussian blue and lead<br />
chromate). Chromium oxide green, however, performs<br />
well with UCAR Solution <strong>Vinyl</strong> <strong>Resins</strong>.<br />
When an iron oxide pigment is desired, use synthetic<br />
iron oxides; they perform well with UCAR Solution <strong>Vinyl</strong><br />
<strong>Resins</strong>. With coatings containing synthetic iron oxides,<br />
use a heat stabilizer, particularly when bake temperatures<br />
may reach 248ºF (120ºC).<br />
Gold bronze metallic pigments are powdered alloys<br />
of copper and zinc. They tend to react with vinyl, causing<br />
color development and gellation. When used to make<br />
gold inks, the powder is stirred into the ink vehicle shortly<br />
before use, and quantities sufficient for the job at hand<br />
are prepared.<br />
There is a minimum amount of pigment that must<br />
be used to impart opacity to ultraviolet light. For example,<br />
about 65 parts of titanium dioxide (TiO 2 ) per 100 parts of<br />
vinyl resin is the minimum amount that should be used.<br />
To obtain maximum hiding power in thin films, about<br />
125 parts TiO 2 per 100 parts of vinyl resin is a practical<br />
maximum concentration. Exceeding this level can cause<br />
excessive chalking. If color pigments are desired, they<br />
can generally be substituted for TiO 2 at an equal volume<br />
replacement. There are exceptions; ultra-fine particle<br />
size pigments, for example, are used at much lower<br />
concentrations.<br />
The use of extender pigments or fillers will help<br />
improve the economics of the formulation. They will<br />
also help prevent sagging of thick wet films on vertical<br />
surfaces, will help control gloss (flatting) at low levels,<br />
and will permit greater film thickness per coat. Talcs,<br />
clays, barytes, and silicas may be used as extender<br />
pigments. If they are used, they will contribute little to<br />
ultraviolet absorption. A sufficient quantity of ultravioletlight-absorbing<br />
prime pigment must be included in<br />
the formulation.<br />
Table 7 provides a listing of pigment types and<br />
loadings typically recommended for UCAR <strong>Vinyl</strong><br />
Copolymer and Hydroxyl-Modified <strong>Vinyl</strong> <strong>Resins</strong>.<br />
Formulation with UCAR Carboxyl-Modified<br />
<strong>Vinyl</strong> <strong>Resins</strong> VMCH, VMCC, and VMCA involves special<br />
considerations. The carboxyl groups of these products are<br />
randomly spaced along the polymer chain and will react<br />
with basic materials to form irreversible gels or increased<br />
consistency of pigment-vinyl combinations. Do not use<br />
basic pigments, extenders, or fillers with UCAR Carboxyl-<br />
Modified <strong>Vinyl</strong> <strong>Resins</strong>. Particularly, avoid lead-containing<br />
pigments (red lead, chrome yellow, chrome orange), zinc<br />
dust or zinc oxide, strontium-containing pigments, and<br />
calcium carbonate. Do not even use small amounts of<br />
these basic materials in pigment blends. With minor<br />
proportions of basic pigments, viscosity aberrations may<br />
not be predictable; some batches may have a normal<br />
viscosity and others will gel. Table 8 lists pigments typically<br />
used with UCAR Carboxyl-Modified <strong>Vinyl</strong> <strong>Resins</strong>.
Typical Pigments for UCAR® <strong>Vinyl</strong> Copolymer<br />
and Hydroxyl-Modified <strong>Vinyl</strong> <strong>Resins</strong><br />
Parts per<br />
Pigment 100 Parts Resin<br />
RED<br />
Pigment Scarlet —*<br />
Permanent Red 2B<br />
(Non-Resinated Calcium, Barium<br />
or Strontium Lakes of 2-B Acid —<br />
BON Reds —<br />
Pyrazolone Reds —<br />
Indanthrene Reds —<br />
Quinacridone Reds —<br />
Perylene Scarlet —<br />
Pyranthrone Scarlet —<br />
Perylene Vermillion —<br />
Iron Oxide, Synthetic Types 55 to 100<br />
YELLOW<br />
Nickel-Titanium Yellow —<br />
Indanthrene Types —<br />
Benzidines —<br />
Nickel Azo Types —<br />
Flavanthrone —<br />
Anthrapyrimidine —<br />
Pyratex Yellows —<br />
Iron Oxide, Synthetic Types 55 to 100<br />
ORANGE<br />
Vat Orange —<br />
Dianisidine Orange —<br />
Benzidine Orange —<br />
Anthanthrone —<br />
GREEN<br />
Phthalocyanine Green 15 to 25<br />
* — indicates that the minimum level of pigment to prevent ultraviolet<br />
light degradation has not been established.<br />
Parts per<br />
Pigment 100 Parts Resin<br />
MAROON<br />
Thioindigo Types —<br />
Alizarine Types —<br />
BON Types —<br />
Perylene Maroon —<br />
BROWN<br />
Iron Oxide, Synthetic Types 55 to 100<br />
BLACK<br />
Carbon Black 5 to 7<br />
Furnace Black 5 to 7<br />
Lampblack 5 to 7<br />
Iron Oxide, Synthetic Types 55 to 100<br />
WHITE<br />
Antimony Oxide —<br />
Titanium Dioxide 75 to 125<br />
Zinc Oxide —<br />
VIOLET<br />
Carbazole —<br />
Carbozole Dioxane —<br />
METALLIC<br />
Aluminum Pastes (65%),<br />
Leafing or Non-Leafing 60 to 85<br />
BLUE<br />
Phthalocyanine Blue —<br />
table 7 25
table 8<br />
26<br />
Typical Pigments for UCAR® Carboxyl-Modified <strong>Vinyl</strong> <strong>Resins</strong><br />
Parts per<br />
Pigment 100 Parts Resin<br />
Aluminum Powder 35 to 50<br />
Titanium Dioxide<br />
Phthalocyanine Green<br />
75 to 125<br />
(Non-Resinated)<br />
Phthalocyanine Blue<br />
15 to 30<br />
(Non-Resinated) 15 to 30<br />
Carbon Black 7<br />
Iron Blue Chalks badly<br />
Iron Oxide Yellow, Synthetica 60 to 125<br />
Iron Oxide Red, Synthetica 60 to 125<br />
Iron Oxide Black, Synthetica 60 to 125<br />
Iron Oxide Brown, Synthetica 60 to 125<br />
Ultramarine Blue Chalks & fades<br />
Zinc Phosphate 75<br />
Talc Use as filler<br />
Clay or extender<br />
Barytes<br />
Silica<br />
pigments<br />
(a) Natural oxides are not satisfactory. Synthetic oxides are satisfactory<br />
in either air-dried or baked coatings.<br />
If water is present in a pigmented coating containing a<br />
carboxyl-modified vinyl, the water molecule may form<br />
a bridge between the polymer’s carboxyl group and the<br />
pigment surface. Silica and alumina hydrate are prone<br />
to bridging or hydrogen bonding. Since most chlorideprocess<br />
TiO 2 pigments have silica, zinc oxide, or alumina<br />
treatments, they can develop hydrogen bonding.<br />
Hydrogen bonding manifests itself as viscosity instability.<br />
The viscosity may increase slowly over a period of several<br />
months or it may increase rapidly in a few days or weeks.<br />
If the water content reaches two percent based on the<br />
weight of carboxyl-modified vinyl, the paint may even gel.<br />
Commercial-grade materials typically limit water<br />
content adequately and should introduce no serious<br />
viscosity instability. If water does contaminate the<br />
formulation, it may come from the solvents or be<br />
introduced through poor storage practices.<br />
Organic acids, mineral acids, and certain acid-esters<br />
will reverse bridging from excessive moisture. Organic<br />
acids (such as citric, maleic, or malonic) or mineral acids<br />
(such as phosphoric) are all effective at concentrations<br />
of one-fourth to one percent, based on the weight of<br />
the carboxyl-modified vinyl resin.<br />
To restore a gelled paint to fluidity, first prepare a<br />
solution of the acid or acid-ester in acetone or other<br />
compatible solvent. Then, slowly add the solution to the<br />
gelled paint with agitation. Acid treatment of the coating<br />
may, however, affect adhesion and reduce gloss.<br />
A small amount of acid or acid-ester can also prevent<br />
or minimize viscosity excursions during paint manufacture.<br />
As with the restoration of gelled paints, this treatment<br />
may also affect adhesion and reduce gloss.<br />
The best way to control viscosity aberrations from<br />
water content is to prevent water from entering the<br />
formulation.
Pigments can be easily dispersed into vinyl coatings<br />
with conventional equipment, such as a pebble mill,<br />
sand grinder, and high-speed stirrers. To prevent iron<br />
contamination, do not use steel ball mills for pigment<br />
dispersion. The most common technique is to dissolve<br />
the vinyl resin in the appropriate solvents. The vinyl<br />
solution is then blended with the plasticizers, stabilizers,<br />
grinding aid, and pigments. For higher gloss coatings,<br />
predisperse the pigment in plasticizer, thinner, and<br />
grinding aid before adding to the vinyl resin solution.<br />
Modification with Other Polymers<br />
Compatibility<br />
The vinyl chloride/vinyl acetate copolymers are compatible<br />
with each other and with most acrylic resins. They<br />
have, however, a low order of compatibility with most<br />
other resin types. UCAR® Carboxyl-Modified Solution <strong>Vinyl</strong><br />
<strong>Resins</strong> will improve the general adhesion characteristics<br />
of other UCAR Solution <strong>Vinyl</strong> <strong>Resins</strong>. They will also<br />
improve air-dry adhesion of many acrylic coatings. UCAR<br />
Hydroxyl-Modified Solution <strong>Vinyl</strong> <strong>Resins</strong> (notably VAGF,<br />
VAGC, VAGH, VAGD) are compatible with a broad range<br />
of other film formers, such as alkyds, melamines, ureas,<br />
epoxies, and urethane prepolymers. Table 9 lists typical<br />
modifiers and shows their relative compatibility with<br />
UCAR Hydroxyl-Modified Solution <strong>Vinyl</strong> <strong>Resins</strong>.<br />
Where maximum gloss is desired, add pigments in either<br />
vinyl pigment chip or vinyl pigment paste form. For faster<br />
dispersion, incorporate wetting agents in the formulation.<br />
Soya licithin or “Nuosperse” 657 (Creanova, Inc.) have<br />
been extensively tested and are effective wetting agents,<br />
when used in concentrations of one to five percent,<br />
based on pigment weight. Other suppliers such as Byk<br />
Chemie offer additives useful for pigment dispersion.<br />
Reactive (Crosslinking) Systems<br />
UCAR Hydroxyl-Modified Solution <strong>Vinyl</strong> <strong>Resins</strong> can<br />
be cured with amino resins or isocyanate prepolymers<br />
to increase film hardness and resistance to solvents,<br />
chemicals, and moisture. <strong>Vinyl</strong> wood sealers cured with<br />
urea formaldehyde resins and acid catalysts cure rapidly<br />
at ambient temperature or short, low-temperature bake<br />
cycles. <strong>Vinyl</strong> coatings for metal containers cured with<br />
phenolic or melamine resins require higher bake<br />
temperatures, but the resulting coatings have excellent<br />
resistance to water immersion, pasteurization, and<br />
steam sterilization. Hydroxyl-modified resins cured with<br />
urethane prepolymers cure at ambient temperature<br />
or low bakes. Films can range from hard to elastomeric<br />
depending on the choice of urethane prepolymer.<br />
27
table 9<br />
28<br />
Compatibility a<br />
of UCAR® Hydroxyl-Modified <strong>Vinyl</strong> <strong>Resins</strong> with Other <strong>Resins</strong><br />
<strong>Vinyl</strong>/Modifier Ratio b<br />
VAGH VAGD VROH<br />
Modifier Resin 4:1 1:4 4:1 1:4 4:1 1:4<br />
Alkyds (non-drying) c<br />
“Beckosol” 12-021, coconut, short oil, PA content - 47% C C C C C C<br />
Alkyds (drying) c<br />
“Beckosol” 11-035, soya, medium oil, PA content - 35% C I C I H I<br />
“Beckosol” 12-005, soya, short oil, PA content - 42% C C C C C C<br />
“Beckosol” 11-070,<br />
linseed/soya, medium oil, PA content - 31% C I C I H I<br />
“Beckosol” 12-054,<br />
tall oil fatty acids, short oil, PA content - 41% C C C C C C<br />
Urea-Formaldehyde <strong>Resins</strong> d<br />
“Beetle” 55 (methylated resin) I I I I I I<br />
“Beetle” 60 (methylated resin) I I I I I I<br />
“Beetle” 65 (methylated resin) I I I I I I<br />
“Beetle” 80 (butylated resin) C C C C C C<br />
Hexamethoxymethylmelamine d<br />
“Cymel” 303 C C C C C C<br />
Melamine-Formaldehyde <strong>Resins</strong> d<br />
“Cymel” 350 C C C C C C<br />
“Cymel” 370 (methylated resin) C C C C C C<br />
“Cymel” 225-10 (rapid-cure resin) H I H I H I<br />
Urethane Prepolymers e<br />
“Mondur” CB-60, aromatic polyisocyanate C C C C C C<br />
“Desmondur” N-75, aliphatic polyisocyanate C C C C C C<br />
“Mondur” HC, polyisocyanate copolymer C C C C C C<br />
Key:<br />
C = Compatible (a) 5-mil (125 microns) wet drawdowns on glass; coatings dried 20 min at 140°F (60ºC) prior to rating<br />
H = Haze in film, but coating uniform (b) Solids basis<br />
I = Incompatible (c) Reichhold<br />
PA = Phthalic Anhydride (d) Cytec Industries<br />
(e) Bayer
Adhesion<br />
For good adhesion, surfaces must be free of rust, grease,<br />
oil, dirt, and other contamination. Common techniques<br />
for cleaning surfaces include solvent wash, vapor<br />
degreasing, chemical treatment, and brush cleaning.<br />
For maximum adhesion, use a phosphate treatment<br />
or a vinyl butyral wash primer before applying the vinyl<br />
coating. Where vinyl butyral primers are used, the next<br />
coat must be based predominantly on hydroxyl-modified<br />
resins (VAGF, VAGC, VAGH, or VAGD).<br />
Maximum adhesion of vinyl coatings is usually<br />
obtained at bake temperatures high enough to drive<br />
out traces of residual solvents. Over porous surfaces, such<br />
as concrete and cloth, mechanical adhesion should be<br />
sufficient for good performance; baking is not generally<br />
Where Not to Use <strong>Vinyl</strong> Coatings<br />
<strong>Vinyl</strong> coatings should not be used in applications where<br />
the continuous service temperature exceeds 140ºF (60ºC).<br />
No specific recommendations can be made for<br />
applications where the service temperature of the coating<br />
exceeds 140ºF (60ºC) intermittently or repeatedly.<br />
The recommendations for the use of heat stabilizers<br />
in UCAR Solution <strong>Vinyl</strong> <strong>Resins</strong>, given elsewhere in this<br />
booklet, are specific to a single-bake operation. The<br />
formulator is cautioned not to directly apply information<br />
about heat stabilizers to applications where service<br />
temperature exceeds 140ºF (60ºC) intermittently. Heat<br />
stabilizers that are effective at high bakes – in excess<br />
of 350ºF (176ºC) – may have an adverse effect on coating<br />
adhesion if used at lower service temperatures.<br />
needed. Baking finishes can be cured with heated air,<br />
infrared radiation, or by heating the metal surface on<br />
which the coating is applied. Control temperature carefully<br />
to avoid overbaking the coating. Maintain proper<br />
ventilation and uniform temperature distribution.<br />
UCAR® Hydroxyl-Modified Solution <strong>Vinyl</strong> <strong>Resins</strong><br />
adhere well to many types of finishes and are quite<br />
useful in applications where coatings based on the<br />
unmodified vinyl resins will not adhere. UCAR Carboxyl-<br />
Modified Solution <strong>Vinyl</strong> <strong>Resins</strong> adhere to clean metal<br />
and to air-dry or baked topcoats or primers. Table 10<br />
compares the air-dry adhesion of coatings based on the<br />
three basic types of UCAR Solution <strong>Vinyl</strong> <strong>Resins</strong>.<br />
29
table 10<br />
30<br />
Air-Dry Adhesion of Coatings Based on UCAR® Solution <strong>Vinyl</strong> <strong>Resins</strong><br />
Substrate VYHH VAGH VMCH<br />
Acrylic and Methacrylic Ester <strong>Resins</strong> Excellent Excellent Excellent<br />
Alkyd Resin Poor Excellent Fair<br />
Cloth Poor Good Fair to Excellent<br />
Concrete (somewhat dependent on type) Good Good Excellent<br />
Glass Poor Fair Fair<br />
Metal (clean and smooth) Poor Poor Excellent<br />
Metal, Phosphatized Poor Fair Excellent<br />
Nitrocellulose Poor Poor Fair<br />
Oleoresinous (varies widely) Poor Fair to Excellent Poor<br />
Paper Poor Good Good<br />
Phenolic <strong>Resins</strong> Poor Good Fair<br />
Plaster (somewhat dependent on type) Good Good Excellent<br />
Rubber, Chlorinated Fair Fair Fair<br />
Shellac Poor Good Poor<br />
Urea <strong>Resins</strong> Poor Good Fair<br />
<strong>Vinyl</strong> Butyral Resin Poor Excellent Fair<br />
<strong>Vinyl</strong> Chloride <strong>Resins</strong> Excellent Excellent Excellent<br />
Wood Poor Fair Fair
Product Safety<br />
When considering the use of any Union Carbide products<br />
in a particular application, you should review our latest<br />
Material Safety Data Sheets and ensure that the use you<br />
intend can be accomplished safely. For Material Safety<br />
Data Sheets and other product safety information,<br />
contact the Union Carbide sales office nearest you. Before<br />
handling any other products mentioned in the text, you<br />
should obtain available product safety information and<br />
take necessary steps to ensure safety of use.<br />
No chemical should be used as or in a food, drug,<br />
medical device, or cosmetic, or in a product or process<br />
in which it may contact a food, drug, medical device, or<br />
cosmetic, until the user has determined the suitability<br />
and legality of the use. Since government regulations<br />
and use conditions are subject to change, it is the user’s<br />
responsibility to determine that this information is<br />
appropriate and suitable under current, applicable<br />
laws and regulations.<br />
Further Information<br />
For information on prices, delivery, and technical service,<br />
phone 1-800-568-4000. For product information on safe<br />
handling, ask for the latest Material Safety Data Sheet<br />
(MSDS).<br />
Union Carbide requests that the customer read,<br />
understand, and comply with the information contained<br />
in this publication and the current Material Safety Data<br />
Sheet(s). The customer should furnish the information<br />
in this publication to its employees, contractors, and<br />
customers, or any other users of the product(s), and<br />
request that they do the same.<br />
31
32<br />
Emergency Service<br />
Union Carbide maintains a 24-hour emergency service<br />
for its products. The Chemical Manufacturers Association<br />
(CHEMTREC), Transport Canada (CANUTEC), and the<br />
National Chemical Emergency Center also maintain<br />
24-hour emergency service:<br />
Location Union Carbide Products All Chemical Products<br />
Mainland United States Phone Union Carbide Phone CHEMTREC<br />
and Puerto Rico HELP: (800) UCC-HELP (800) 424-9300 (toll-free)<br />
(toll-free), which numerically<br />
is (800) 822-4357<br />
Alaska and Hawaii Phone Mainland United States: Phone CHEMTREC:<br />
(304) 744-3487 (collect) (800) 424-9300 (toll-free)<br />
Canada Phone Union Carbide: Phone CANUTEC:<br />
(514) 640-6400 (collect) (613) 996-6666 (collect)<br />
Continental Europe, Ireland, Phone BIG (Geel-Belgium) Phone CHEMTREC (United States):<br />
Middle East, North and Central Africa (32)(0) 14 58-45-45 (703) 527-3887 (collect)<br />
United Kingdom Phone National Chemical Phone CHEMTREC (Unites States):<br />
Emergency Center (Culham-UK) (703) 527-3887 (collect)<br />
(44)(0) 1865-407-333<br />
Latin America, Asia/Pacific, South Africa Phone United States: Phone CHEMTREC (Unites States):<br />
and any other location worldwide (304) 744-3487 (collect) (703) 527-3887 (collect)<br />
At sea, radio U.S. Coast Guard, who can directly contact Union Carbide HELP…<br />
(800) 822-4357 (toll-free) or CHEMTREC… (800) 424-9300 (toll-free).<br />
DO NOT WAIT! Phone if in doubt! You will be referred to a specialist for advice.
U<br />
Union Carbide Corporation<br />
39 Old Ridgebury Road<br />
Danbury, CT 06817-0001<br />
UC-669B<br />
P8-8429<br />
10/98 –3M<br />
Printed in U.S.A.