Supply Program Flame Retardants - HARKE Group

Supply Program Flame Retardants

Overview:
Flame Retardants
n Chlorinated Paraffins 4
n Antimony Oxide 5
Intumescence-Flame Retardants
n Ammonium Phosphates 6
n Organic Trisphosphates 7
n DOPO 10
HARKE Chemicals GmbH stands
for certified quality and constant
engagement for a sustainable
protection of the environment.

Effektive Fire Protection
Potential combustion sources may lurk everywhere and can ignite
upholstery, cars or electronic devices. Flame retardants are used in order
to make those less easily flammable. Especially plastics are easily and
fast flammable, and thus these materials make high demands on fire
protection. Flame retardants play an important role in the reduction of
risks and spread of fire by providing time to escape, and thus property
as well as environment can be protected.
For each particular case the most suitable flame retardant should be
used because the positive effects of fire protection may be accompanied
by negative ones, as for instance the release of detrimental odors.
During the last years the standards of modern flame retardants have
changed. Apart from the effective fire protection also the environmental
protection plays a more and more important role throughout the whole
life time cycles of the products. Thus modern flame retardants should
not be toxic for people, animals and plants.
Benchmarking of Flame Retardants
Halogenated
Flame Retardants
Intumescence-
Flame Retardants
Place of Action Gas Phase Cond. Phase
Principle of Action Chemical Chemical/
Physical
Performance + +
Polymer Compatibility + +
Side Effects Strong Smoke
Development
Weak Smoke
Development

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Flame Retardants
Advantages of
Cloparin ®
n Boiling point at >200° C
n Extremely resistant against
acids and alkalis
n Soluble in most organic
solvents
n Insoluble in water and
short-chain alcohols
Chlorinated Paraffins – Cloparin ®
Chemical Character
In the field of halogenated flame retardants we offer various types
of the trade mark Cloparin ® . These chlorinated paraffins consist
of chlorinated hydrocarbons, which can be produced in different
chain lengths depending on their applications.
Fields of Application
Short-chain chlorinated paraffins are mainly applied in cooling
lubricants which are used for the industrial metal production.
Medium- and long-chain chlorinated paraffins are suitable as
flame retardants and plasticizers for rubber products and plastics.
Cloparin ® is mainly used in PVC-compounds. The different types
can be used both as flame retardants and as plasticizers, and thus
replace partly or even totally the conventional plasticizers.
According today’s state of knowledge chlorinated paraffins are
considered as environmentally dangerous materials. This especially
concerns the short-chain products. The chain length ranges from
C10 to C30, and the chlorine content from 20 % to 73 %.
Mode of Action
Similar to all halogen compounds the flame-retardant effect of
chlorinated paraffins depends on their capacity as scavenger. The
non-combustible hydrogen chloride is eliminated at high temperatures,
and additionally chain break-up reactions disturb the combustion
process and the flame expansion. In order to achieve the same
flame-retardant properties as the bromine compounds, often twice
the amount has to be formulated.
Chlorinated paraffins decompose only at higher temperatures of
>200° C, and are chemically almost inert. This means that at normal
conditions they react not at all or only to an evanescently little degree
with potential reaction partners, like e.g. air.

Types and Properties
Our chlorinated paraffins feature various viscosities and
chlorine contents whereby the right compatibility and
performance is ensured for any application. They are
compatible with most resins and polymers, as for instance
with natural and synthetic rubber, chlorinated polyethylene,
polyester, polystyrol, polyacrylate, PVC, polyvinyl acetate
and chlorinated copolymers. Furthermore, our Cloparin ®
types are also well mixable with other additives like
phthalates, stearates and phosphates.
Antimony Oxide (Sb 2 O 3 )
Chemical Character
Antimony oxide is a very fine, crystalline white powder
having a controlled particle size. At high temperatures it
stores oxygen atoms and becomes antimony tetraoxide.
Fields of Application
Besides the application in flame retardants antimony oxide is
for instance used in plastics as a catalyst or for discoloration
of glass. Moreover, it is used in enamel productionand
electroplating.
Mode of Action
Antimony trioxide is a chemical used in flame retardants as
a synergist in order to, for instance, intensify the effect of
chlorinated paraffins.
Properties
Antimony trioxide is insoluble in water and nitric acid. It is
little soluble in sulfuric acid and hydrochloric acid, whereas
it, however, shows a better solubility in a concentrated
solution.
Cloparin ® 50 Broad application
spectrum
Cloparin ® 44 F Low viscosity
Cloparin ® 56 Broad application
spectrum
Cloparin ® 49 ST Medium viscosity,
high stability
Cloparin ® 56 ST High viscosity
and stability
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Intumescence-Flame Retardant
Ammonium Phosphates
Chemical Character
Ammonium phosphate is extracted from the sal ammoniac of phosphoric acid and can be used
as intumescence flame retardant. In this field we offer two products, namely the acid monoammonium
phosphate, also named MAP, and the alkaline diammonium phosphate, known under the
acronym DAP.
Fields of Application
The inorganic acid phosphates are preferably used as flame retardants in cellulose material, e.g. in
viscose. The inorganic alkaline phosphates are preferred as flame retardants for wood, e.g. for forest
fire fighting.
Mode of Action
Heated and in the presence of oxygene the phosphate compounds decompose to water vapor and
phosphor oxides. The latter react with the polymer matrix and dehydrate it. Thus phosphoric
acid is formed, which decomposes to phosphor oxide through heat forming water vapor.
Ammoniac is split into water and nitrogen and thus the retardant process is further supported.
At the same time phosphor oxide forms high-melting glass-like coatings between the surface
of the polymer matrix and the heat source. On the one hand these coatings cause a fast
circulation of the thermal energy, and on the other hand eliminate the pocket of embers
by quenching.

Types and Properties
Types Characteristic Unit Typical Values
Monoammonium Phosphate
NH 4 H 2 PO 4
Diammonium Phosphate
(NH 4 ) 2 HPO 4
Advantage: Broad Application Spectrum
Organic Trisposphates
Chemical Character
Organic trisphosphates are chemical compounds of the group
of phosphoric acid esters. There exists a great number of the
so-called organic substituted trisphosphates that may show
numerous isomers in the individual compounds.
Fields of Application
N % 12
P 2 O 5 % 61
pH (1 mol) 4
Loss on Drying % 0.1
Content % 99.8
Insolubles % 0.01
Bulk Density g/l 900
Water Solubility g/l 365
N % 21
P 2 O 5 % 54
pH (1 mol) 8.1
Loss on Drying % 0.05
Content % 100
Insolubles % 0.01
Bulk Density g/l 1000
Water Solubility g/l 690
Phosphor compounds are often used as flame retardants in plastics; mainly when producing soft
PVC, which is used as floor covering, for manufacturing seals, cable coatings, canvasas and coatings
as well as in the construction sector.
Phosphoric acid compounds also unfold their retardant effect in the synthesis of caoutchouc or
polyurethan elastomeres. These rigid foam plastics conduce to thermal insulation and mostly
contain the low viscous trichlorisopropyl phosphate (TCPP). Diphenylcresyl phosphate (DCP) is
mostly used in epoxy resins as substitute for brominated bisphenol A resins.
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Mode of Action
Phosphor compounds function in the gas phase by releasing
highly effective scavengers that act as flame retardants through
cutting-off the radical chain reaction. Furthermore, phosphoric
acid dehydrates the polymer surface to a charred layer. This
so-called carbon film prevents further feeding with oxygen, and
thus impedes the advancement of the oxidate corrosion.
The mechanism is especially effective with oxygenic polymers
because of the combination of phosphoric acid ester with fillers
like aluminium trihydrate a glassy slag is formed on the surface
during fire.
The organic trisphosphates can also be used in oxygen-free
polymeres.
The Chemical with a Double Effect
When adding plasticisers as for instance diethylhexal phthalate
(DEHP) the effect is that the combustibility of the plastic rises.
This makes the use of flame retardants indispensable, therefore,
diethylhexyl phthalate is often combined with inorganic flame
retardants.
Instead of using two chemicals you can change to only one.
The phosphor compounds feature both the retardant effect and
pasticising properties and thus counteract the brittleness of the
plastic.

Types and Properties
Type Formula P Content (%) Properties
Diphenyl Cresyl Phosphate
DCP C 19 H 17 O 4 P 9.1 DCP replaces brominated bisphenol A types
in epoxy resins. In addition to that it offers
plasticising properties.
Triethyl Phosphate
TEP C 6 H 15 O 4 P 17 TEP features two properties: In addition to its
flame retardant effect it is able to lessen the
viscosity of highly viscous polymeres. TEP is also
used as solvent, catalyst, and ethylising reagent.
Moreover, it is comparably low-priced.
Tricresyl Phosphate
TCP C 21 H 21 O 4 P 8.4 TCP is a flame retardant plasticiser with excellent
hydrolysis stability, oil durability, super electrical
isolation and a highly fungicidal effect. Principal Uses:
As plasticiser and flame retardant in PVC, polyethylene,
in certain leather kinds, synthetic resins and
cables. Furthermore, TCP is used when formulating
lubricants that have to stand high pressure or in
inflammable hydraulic oils.
Triphenyl Phosphate
TPP C 18 H 15 O 4 P 9.5 TPP is preferred as a retardant plasticiser in
cellulose compounds and synthetic rubber.
It has a high flame retardant effect and very
good mechanical properties. TPP is also used in
paints and lacquers as well as in polyurethane
high-density foams.
Trioctyl Phosphate
TOP C 24 H 51 O 4 P 7.1 TOP is a comparably high molecular flame
retardant and plasticiser with a very low emission
grade. Very low fogging.
Diphenyl Octyl Phosphate
DPOP C 20 H 27 O 4 P 8.6 DPO is used as flame retardant in phenol resins
and PC / ABS-blends. It features very good
plasticising properties.
Tris (2-chloro-1methyl-ethyl) Phosphate
TCPP C 9 H 18 Cl 3 O 4 P 9.5 TCPP is a plasticising flame and viscosity
controlling retardant for polyurethanes.
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DOPO
Chemical Character
DOPO is a halogen-free flame retardant. DOPO stands for
9.10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide. It
shows properties similar to the often-used brominated epoxy
resins, however, without evaporation. The reason for this is that
it is chemically bound to the matrix. During processing you have
to keep in mind that DOPO has to be used together with multifunctional
epoxy resins as for instance Novolacs because of the
fact that one epoxy group reacts at a time with one molecule
DOPO.
Fields of Application
Considering that common flame retardants evaporate, and that
this may lead to a significant health risk, the general trend goes
to halogen-free flame retardants.
With DOPO we offer a product that features excellent flame retardant
properties without evaporating harmful smells or odors.
DOPO is used in epoxy resins applied in the area of computer
circuit boards. Furthermore, it is always used where fire protection
is necessary, but harmful smells or odors are not welcome
as for instance in polyurethane, which is processed in mattresses,
construction foam, foam materials or upholstery. DOPO is
also used in high-power transformers on vessels, in the field of
automotive and aviation industry as well as in household products.
DOPO is also interesting for construction elements that
are exposed to higher temperatures.
Mode of Action
The mode of action is based on three processes: A highly flameretardant
carbon layer is formed on the surface, functioning like
a protective coating and thus reducing the amount of flammable
material. This process is also called “charring“.
A further effect arises through intumescence. By means of induction
of more gases a voluminous protection layer is formed.
Thirdly, PO-radicals form through heat and take part in the
radical combustion process.

Comparison of DOPO with
brominated epoxy resins
n Similar melting point
n Same hardener types possible
n Processing with the same fillers possible
n Melting viscosity in similar range (125° C)
n Soluble in acetone, MEK and toluene
n Lighter than brominated epoxy resins
n No evaporation of toxins
Types and Properties
P in % Blistering
Features of DOPO
Smoke
Formation
Flammability
-
Rating
n Compliance of requirements concerning halogen-free
epoxy resins in laminates
n Disadvantages with respect to thermal and mechanical
properties of some phosphor organic compounds are
avoided
n Incorporation of high glass temperature and absence
of halogens if DOPO is chemically connected with the
polymer matrix
n Depending on how much DOPO is added, the epoxy
equivalent EEW will increase from 200 to 270 - 450
LOI
in %
Novolac / Dicy 0 Yes No V-2 24
Novolac / Dicy 1.86 No No V-0 34
Novolac / Dicy 3.83 No No V-0 38
Novolac / DDS 0 Yes Yes V-2 23
Novolac / DDS 1.69 No No V-0 27
Novolac / DDS 3.63 No No V-0 33
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03/11