A-Stage
An early stage in the reaction of certain thermosetting resins in which
the material is fusible and still soluble in certain liquids.
Accelerator
A chemical additive which speeds up the rate of a chemical reaction and
thereby reduces the gel time and cure time. Another term is promoter.
Adhesion
The property of forming a steady or firm attachment.
Adhesive Failure
The failure at the bond line between a substrate and an adhesive; the
adhesive separating entirely from the substrate.
Aging
The change in properties of a material with time under specific conditions.
Ambient Temperature
The temperature of the surrounding environment.
Amine
Curing agent for epoxy resins that is any of a class of ammonia derivatives.
They are derived from Ammonia.
Arc Resistance
The time required for an arc to establish a conductive path in a material.
B-Stage
The intermediate stage during the curing process when the material has
gelled but is not fully cured.
Bond Strength
A measure of force or pressure required to separate a layer of material
from its base.
Breakdown Voltage
The voltage at which the insulation between two conductors will break
down. See Dielectric Strength.
Brookfield Viscometer
An instrument for measuring the viscosity of adhesives under standard
conditions of temperature.
C – Stage
The final stage in the reaction of certain thermosetting resins in which
the material is relatively insoluble and infusible. Certain thermosetting
resins in a fully cured state are in this stage.
Cast
To form plastic objects by pouring a fluid system into an open mold.
Catalyst
A material which initiates and/or accelerates a chemical reaction but
normally does not enter into the reaction.
Centigrade
A scale of temperature which uses 0º and 100º as the freezing
and boiling point of water respectively. To convert centigrade to Fahrenheit,
multiply by 1.8 and add 32.
Centipoises
A unit of viscosity (with water as the standard = 1.0) for indicating
the fluidity or flow property of a liquid at room temperature. 1/100 of
a poise.
Chalking
Formation of a dry powdery chalk-like appearance or deposit on the surface
of a material. It is due to a breaking down of the material after being
exposed to ultraviolet light, or to other weathering.
Chemical Resistance
A measure of the sensitivity of a material to attack or corrosion by a
chemical material.
Classes Of Insulation
Arbitrary temperature ratings based on composition and/or experience with
a particular material.
Coating
A finishing, protecting, or enclosing layer that seals a component from
its immediate environment.
CTE
Coefficient Of Linear Thermal Expansion The fractional change in length
of a material for a unit change in temperature. Measured in inch/inch/°F
or cm/cm/°C.
Cohesion
The internal affinity of a material to itself.
Cohesive Failure
Failure within the adhesive under a stress, resulting in a broken bond
with all adherent surfaces still covered with adhesive.
Compressive Strength
A measure of the resistance of a material to a crushing load. Measured
in pounds/square inch or megapascals.
Conductivity (Electrical)
The reciprocal of volume resistivity. Conductance of a unit cube of any
material.
Copolymer
A compound resulting from the chemical reaction of two chemically different
monomers with each other.
Cross-Linking
Reacting together large molecules to change the physical properties of
material. Cross-linking involves formation of a three dimensional molecular
network with thermosetting resins.
Cure Cycle
The time and temperature necessary for a material to reach most of its
optimum properties.
Cure Time
The time for reacting thermosetting plastic or rubber composition to reach
certain properties. For materials which react under the conditions of
mixing, the start of reaction is the time of initial exposure to the conditions
necessary for reaction to occur.
Curing Agent (Hardener)
A cross-linking agent that reacts with a resin to form a copolymer.
Curing Temperature
The temperature at which a material cross-links or cures.
|