Glossary of Terms - Paints and Coatings - Brenntag Specialties, Inc.

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CLASSES OF SOLVENTS Oxygenated Solvents: General designation of those solvents which contain oxygen in addition to carbon and hydrogen in the molecular. Oxygenated Solvents or “Oxys” may be divided into several chemical types. *Ketones - A class of active, strong solvents characterized by a carbonyl group. Trade names include acetone, methyl ethyl ketone, methyl isobutyl ketone and diacetone alcohol ketones. *Esters - A class of active solvents formed from organic acids and alcohols by the elimination of water. *Alcohols - Latent solvents for many materials. Characterized by the presence of a Hydroxyl (-OH) group. Capable of strong hydrogen bonding. Trade names include isopropyl alcohol, n-butyl alcohol, isobutyl alcohol, secondary butyl alcohol, methyl isobutyl carbinol and 2-ethyl hexanol. *Glycol Ethers - Prepared from alcohols and ethylene or propylene oxide. Glycol ethers contain both ether groups and hydroxyl groups, thereby possessing the characteristics of both. Trade names include butyl ether of ethylene glycol and the butyl ether of diethylene glycol. Hydrocarbon Solvent Types: Compounds composed exclusively of hydrogen and carbon atoms. There are several types of hydrocarbon compounds. *Olefins - Characterized by unsaturation. Relatively reactive, used as a raw material for manufacturing many solvents. Not used in hydrocarbon solvent directly, although traces of olefins may be found in some hydrocarbon solvents. *Paraffins - Completely saturated hydrocarbons characterized by a chain structure. Poorest solvency of the hydrocarbon solvents. Lowest odor. *Naphthenes - Completely saturated hydrocarbons characterized by ring structures. Intermediate solvency between paraffin and aromatic hydrocarbons. Intermediate odor. Also known as cycloparaffins. *Aromatics - Characterized by unsaturated, six carbon benzene ring structures. Hydrocarbon solvents which contain more that 50% aromatic compounds are designatd as aromatic hydrocarbon solvents. Strongest of the hydrocarbon solvents. Strongest odor. Chlorinated Hydrocarbons: Characterized by the presence of chlorine. Glossaries 8 Nitroparaffins: Characterized by the presence of a nitro group. SOLVENT STRENGTH Aniline Cloud Point: A measure of solvent strength, used for aliphatic hydrocarbon solvents only. The Aniline Cloud Point is defined as the minimum temperature at which a 1/1 by volume mixture of hydrocarbon and pure aniline are miscible with each other. The Aniline Cloud Point is also known as Aniline Point and Aniline Number. The standard test method is ASTM D-611. Fractional Polarity: A measure of the polar character of a solvent. Values range between zero and one, the higher the value, the more polar the solvent. Hydrocarbons have very low polarity, while oxygenated solvents have higher polarity. Hydrogen Bonding Index: Measure the strength of the hydrogen bonding that occurs in a solvent. Hydrogen bonding values range from -18 to +15. Hydrocarbons display little hydrogen bonding ability, alcohols are strong hydrogen binders, and other solvents are intermediate between these two extremes. While there are different systems for measuring hydrogen bonding capability, the Shell system is based on infrared analysis of the solvent. Kauri-Butanol Value: A measure of solvent strength, used for hydrocarbon solvents only. A solution of Kauri gum in n-butyl alcohol is titrated to a specified degree of turbidity with the hydrocarbon solvent being tested. Values range from 20+ to 105. The higher values denote stronger hydrocarbon solvency. Typical aliphatic hydrocarbons have KB Values between 28 and 40, while aromatic hydrocarbons have KB Values above 70. The standard test method is ASTM Method D-1133 Mixed Aniline Cloud Point: A measure for solvent strength, used for aromatic hydrocarbon solvents only. The same equipment is used as for the Aniline Cloud Point employed for aliphatic hydrocarbon solvents, except that the aromatic hydrocarbon solvent is diluted with an equal volume of pure n-heptane before mixing with aniline. The standard test method is ASTM D-611. Solubility Parameter: A measure of solvency whose major usefulness lies in predicting whether a particular solvent will dissolve a particular resin. Based on heat of vaporization of the MINERALS COLORS CHEMICALS ADDITIVES RESINS EQUIPMENT
solvent. Stronger solvents generally have higher solubility parameter values. Solvent Power: A general term denoting the ability of a solvent to dissolve resin or binder and hold it in solution. Also known as solvency. SOLVENT EVAPORATION t90: The length of time required for 90% of the weight of the solvent to evaporate at standard conditions. Another convenient way to compare the evaporation rates of solvents. The standard test method is ASTM Method D-3539, the Shell Thin Film EvaporOmeter. In that test method, a measured volume of solvent is dispensed onto a piece of filter paper. The weight is recorded automatically, then the evaporation rate is calculated using a computer program. Distillation Range: The temperature range over which a mixture of liquids will distill. The range is narrow for most oxygenated solvents, because they are essentially pure chemical compounds. Hydrocarbon materials have wider distillation ranges, some quite wide. ASTM Method D- 86 is used for hydrocarbon solvents, D-828 for oxygenated solvents. Flash Point: The lowest temperature at which a liquid gives off sufficient vapor to form an ignitable mixture with air. This concentration is also known as the Lower Flammability Limit. The two most widely used test methods are Tagliabue Closed Cup (TCC), ASTM Test Method D-56, and the Setaflash tester, ASTM Test Method D-3828. Any solvent which has a flash point below 141° F is designated “Red Label” and must have a specific warning sticker attached. Relative Evaporation Rate: The evaporation rate of a solvent compared to a standard, usually n-butyl acetate, with the rate of nbutyl acetate set equal to 1.00. Solvents which evaporate faster than n-butyl acetate have a relative evaporation rate greater than one. Those which evaporate more slowly have a relative evaporation rate of less than one. Vapor Pressure: The pressure exerted when a liquid is in equilibrium with its own vapor. A liquid, enclosed in a given space at a given temperature, will evaporate until the Glossaries 9 pressure of the liquid in the gas phase is equal to the pressure of the liquid at that temperature. The vapor pressure of a solvent is a fundamental thermodynamic property controlling volatility, evaporation and distillation. A solvent with a higher vapor pressure at a given temperature will evaporate faster and distill at a lower temperature. Volatility: The tendency of a substance to evaporate. SOLVENT GRADES: Electronic Grade: Electronic industry solvent specifications are concerned mostly with metals content, especially heavy metals and particulate matter content. Most solvents will meet those specifications as produced. However, contamination during shipping and handling can occur very easily, rendering the solvent unsuitable. Since dust is everywhere, careful filtration is needed at the point of use in the electronics plant. National Formulary (NF) Grade: Standards for certain pharmaceuticals and reagents published by the American Pharmaceutical Association. Recognized as official standards by the Pure Food and Drug Act of 1906. Since 1974, the National Formulary has been combined with the United States Pharmacopeia (USP). United States Pharmacopeia (USP) Grade: A legally recognized compendium of standards for drugs, published by The United States Pharmacopeial Convention, Inc., and revised periodically. It also includes assays and tests for the determination of strength, quality and purity. The USP lists specifications for a number of solvents used in the pharmaceutical industry. Specifications covering specific gravity, distillation range, residue on evaporation and acidity are the most common. For materials for which a USP standard has not been established, the ACS Reagent grade is frequently specified. The American Chemical Society standards are published in ACS Reagent Chemicals. Urethane Grade: Urethane grade solvents are needed for use with urethane formulations. Any substance which contains active hydrocarbons capable of reacting with isocyanates will be restricted to very low levels. Specifications for urethane grade solvents typically center on very low water and alcohol contents, typically 0.1% or less. Glycol ethers also contain active hydrocarbons and are not suitable for use in urethanes. MINERALS COLORS CHEMICALS ADDITIVES RESINS EQUIPMENT
Page 1 and 2: TOPICS COVERED: • Paint and Coati
Page 3 and 4: Pigment: The fine solid particles u
Page 5 and 6: paint in predominating amount with
Page 7: copolymerized with styrene resin em
Page 11 and 12: Federal Implementation Plans (FIP
Page 13 and 14: Volatile Organic Compounds. (VOC’

Glossary of Terms - Paints and Coatings - Brenntag Specialties, Inc.

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