Glossary

A-Stage

An early stage in the reaction of a thermosetting resin in which the material is still soluble and fusible.

A material which, when mixed with a catalyzed resin, will speedup the chemical reaction between the catalyst and resin; either in polymerizing of resins or vulcanization of rubbers. Also known as ‘promoter’. Examples are diethylaniline, cobalt naphthana and cobalt octoate.

Actual End Count

The number of bundles or splits that are actually counted in one doff of roving. (This is less than the theoretical end count due to splitting efficiencies of less that 100%.)

Additive

Any substance added to another substance, usually to improve properties, such as plasticizers, initiators, light stabilizers, and flame-retardants

Adherend

A body that is held to another body, usually by an adhesive. A detail or part prepared for bonding.

Adhesion

The state in which two surfaces are held together at an interface by mechanical or chemical forces or interlocking action or both.

Adhesion Promoter

A coating applied to a substrate before it is coated with an adhesive, to improve the adhesion of the plastic. Also called primer.

Adhesive

A substance capable of holding two materials together by surface attachment. Adhesive can be in film, liquid, or paste form.

Adhesive Failure

Rupture of an adhesive bond such that the separation appears to be at the adhesive-adherend interface.

Adhesive Film

A synthetic resin adhesive, with or without a film carrier fabric, usually of the thermosetting type, in the form of a thin film of resin, used under heat and pressure as an interleaf in the production of bonded structures.

Adhesive Strength

Strength of the bond between an adhesive and an adherend.

Air Entrapment

Occlusion of air in a resin or resin glass system, giving rise to blisters, bubbles or voids in the system.

Air Splice

The coupling between two roving doffs which is made by a jet of air entwining/snarling the two strands together. The air splice is used instead of a knot.

Air Vent

Small outlet, to prevent entrapment of gases.

Air-Bubble Void

Air entrapment within and between the plies of reinforcement or within a bondline or encapsulated area; localized, noninterconnected, spherical in shape.

Amine Resins

A synthetic resin derived from the reaction of urea, thiourea, melamine or allied compounds with aldehydes, particularly formaldehyde.

Anisotropy

The tendency of a material to exhibit different along the directions parallel to the length or width into the lamination planes; or parallel to the thickness into the planes perpendicular to the lamination.

Anti-Static Agents

Agents which, when added to the moulding material or applied on the surface of the moulded object, make it less conducting (thus hindering the fixation of dust).