To find the definition of a term, click on the corresponding first letter of the word above.
Additive. Additives combine with a Silastic® silicone rubber base to enhance processing or performance characteristics of the compound.
Adhesion. The degree of attachment or bonding of one substance to another.
Antifoam. Prevents the formation of foam. (See Defoamer, Deaerator, Foam Control.)
Autoclave Vulcanization. A method of curing rubber with the use of steam.
Base. A base is a silicone polymer with reinforcing fillers and process aids.
Bonding. The process of adhering silicone rubber to a substrate.
Breathable Coating. A coating with a perm rating above about 0.5 perm. The opposite of a vaporretarder. The higher the perm rating, the more breathable the coating.
Calendering. The process of forming silicone into uniform thin sheets.
Catalyzing. The addition of a curing agent to allow for heat curing of silicone rubber.
Caulking Stacy. Stacy testing glossary web.
Coating. A liquid or semiliquid protective finish capable of application to thermal insulation or other surfaces, usually by brush or spray, in moderate thickness.
Combustible. Capable of uniting with air or oxygen in a reaction initiated by heating, accompanied by the subsequent evolution of heat and light. Capable of burning.
Compound. A compound is a ready-to-use blend of a silicone rubber base, fillers, modifiers, vulcanizing agents, and pigments.
Compression Molding. A process of curing silicone by use of a molding method whereby a preform is placed into one half of a heated mold and the mold is closed. Pressure is applied and the preform is forced into all parts of the mold cavity.
Condensation. The process of changing from a gas or vapor to a liquid.
Contaminants. Something that makes a surface or substance unclean, pollutes, soils, stains from an outside source.
Coverage Rate. Quoted either as square feet covered by a gallon (50 ft2/gal) or as gallons used per square (2 gal/square). (A square is 100 square feet.)
Crosslinking. When rubber is heated to the required temperature, peroxide decomposes to form free radicals that react with the organic groups in the silicone polymer. In an addition cured silicone rubber, the catalyst activates the reaction between the crosslinker and reactive organic groups in the silicone polymer. This results in crosslinking between organic groups. The number and position of these linkages determine the degree of vulcanization.
Cure. To change the properties of a plastic or resin by chemical reaction, which, for example, may be condensation, polymerization, or addition; usually accompanied by the action of either heat or catalyst or both, and with or without pressure.
Cure Time. The time required to complete the cure process.
Curing. The degree of vulcanization of the rubber; also known as Heat Aged Curing
Deaerator. Remove small air bubbles from the applied coating. (See Antifoam, Defoamer, Foam Control.)
Defoamer. Destroys foam after its formation. (See Antifoam, Deaerator, Foam Control.)
Elastomer. A material capable of elongating at least 100% and recovering its original dimensions.
Elongation. Lengthening or stretching ability to accommodate movement.
Extrusion. Continuously forcing rubber through a die that forms it into the desired size and shape.
FKM. Fluorocarbon Elastomer
Flash Point. The flash point of a liquid is the lowest temperature of the liquid at which it gives off vapor sufficient to form an ignitable mixture with the air near the surface of the liquid or within the vessel used.
Flexography. Printing process utilizes special (Anilox) rollers containing small cells that carry the ink from the ink fountain to the plate.
FLSR. Liquid Fluorosilicone Rubber
Foam Control. Reduction or elimination of foam (a dispersion of a gas in a liquid or a solid) formed in a coating or a coating constituent.1 (See Antifoam, Defoamer, Deaerator.)
FSR. Fluorosilicone Rubber
FVMQ. ASTM standard for silicone that has good oil and fuel resistivity (Fluorosilicone Rubber); VMQ is the ASTM standard for general purpose and high strength silicone rubber
General Metal. Market that covers all metal coatings with the exception of automotive, metal containers and metal furniture; i.e., steel structures, doors, wire, aluminum.
HCR. High Consistency Rubber (Heat Cured Rubber)
Heat Aged Curing. The degree of vulcanization of the rubber.
Heat Set. Method of drying letterpress and lithographic inks under the action of heat by the evaporation of their high-boiling solvents.2
HVA/Hot-Air Vulcanization. A method of curing rubber with the use of hot air.
Impact Resistance. Ability to withstand mechanical or physical abuse under severe service conditions. Resistance to blows, bumps and shocks incidental to use.
Injection Molding. A process for curing or molding parts by injection of rubber into a cavity.
Intaglio. Printing from flat copper or steel die plates in which the image has been engraved. Intaglio inks are of viscous consistency composed of modified lithographic type varnishes.
Light Concrete. A nonstructural concrete using materials such as vermiculite or perlite as aggregate.
LSR. Liquid Silicone Rubber
Molding/Moulding. The method of heat curing rubber by using compression, transfer or injection molding equipment.
MQ. ASTM standard for general purpose and high strength silicone rubber; also known as VMQ
Pigmenting. The addition of color to silicone.
Pinhole. A very small hole or imperfection in a coating through which water or ultraviolet light can enter and cause damage.
PMQ. ASTM standard for extreme low temperature service silicone rubber; also known as PVMQ
Polymer. A chemical compound or mixture of compounds formed essentially of repeating structural units.
PVMQ. ASTM standard for extreme low temperature service silicone rubber
Resin % of Market. The estimated percent of the market represented by the resin and delivery system for a given application.
Scorch. The premature vulcanization of the rubber - before the flow of rubber in the mold is complete.
Solids Content. The percentage of nonvolatile matter that may be measured in volume orweight.
Solvent. Any substance, usually a liquid, that dissolves other substances. Incoatings, normally a liquid organic compound used to make a fluid coating applymore freely.
Tensile Strength. The force per unit area that is applied at the time of rupture of the specimen. It is calculated by dividing the breaking force in pounds by the cross-section of the unstretched specimen in square inches.
TPE. Thermoplastic Elastomer
Transfer Molding. Unvulcanized rubber is placed in a chamber (called a pot), usually at the top of the mold, and the assembly is placed in a press. The press applies pressure to a piston-like plug in the open end of the pot, clamping the halves of the mold together and forcing the rubber to flow through the heated mold.
UV. Ultraviolet radiation or sunlight.
Vent. A breather vent. A device put in a roof system to allow moisture vapor to escape.
Viscosity. The property of resistance to flow exhibited within the body of a material.
VMQ. ASTM standard for general purpose and high strength silicone rubber
Vulcanization. The rubber cures when it is heated to the required temperature; peroxide decomposes to form free radicals that react with the organic groups in the silicone polymer.
Water Absorption. The increase in weight of a test specimen expressed as a percentage of its dry weight after immersion in water for a specified time.
Water Repellency. Control of water absorption through the coating. Water beading is sometimes used as an indication of water repellency.
Water Repellent. A material that has the ability to hinder the penetration of water. Also used as an adjective to describe such a material e.g. the man applied a water repellent stain to his deck.