Rubber Extrusions Material selections adhesion fundamentals adhesive types and characteristics surface preperations and applications common uses of seals glossary of terms

Glossary of Terms

Abrasion: the surface loss of material due to frictional forces

Blister: a raised spot in the surface, or a separation between layers, usually forming void or air- filled space in the profile

Cell: a single small cavity surrounded partially of completely by walls

Cellular Rubber: rubber products containing many cells or small hollow receptacles dispersed throughout the mass

Closed Cell: a cell totally enclosed by its walls and hence not interconnecting with other cells

Compression Deflection: PSI to compress lab slab a specified percentage of overall height, normally 25%

Compression Set: the amount by which a rubber specimen fails to return to its original shape after release of compressive load

Crazing: A surface effect on rubber articles characterized by many minute cracks

Cross Section: A seal as viewed if cut at right angles to the molding line, showing internal structure

Durometer: (a) an instrument for measuring the hardness of a rubber; measures the resistance of permanent indentation into the surface of the rubber; (b) numerical scale of rubber hardness

Memory: the tendency of a material to return to original shape after deformation

Ozone Cracking: the surface cracks, checks or crazing caused by exposure to an atmosphere containing ozone

Rebound: a measure of the resilience, usually as a percentage of vertical return of a body, which has fallen and bounced

Skin: a relatively dense layer at the surface of a cellular material

Substrate: a material upon the surface of which an adhesive is applied for any purpose such as bonding or coating

Weathering: the surface deterioration of a rubber during outdoor exposure