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Types of adhesive used for bonding plastics

Type Base material Setting Comments

mechanism

Cyano- Acrylics Chemical Rapid curing.
acrylates reaction with Usually not
surface gap-filling.
moisture
Elastomers Polyurethanes, Physical, High peel
silicones, pressure strength. Not

polysulphides, sensitive gap-filling.
nitrile rubbers

Epoxies Epoxies Chemical, by One or two-

reaction with part systems.

hardener Gap-filling.

Hot melts Polyamides, Physical Gap-filling
polyesters,
polyethylenes,

polysulphones,
EVA
copolymers

Poly- Polyurethanes Chemical, by One or two-

urethanes reaction with part systems.
moisture or Gap-filling.
hardener

Toughened Acrylics, Chemical, by Two-part
acrylics methacrylics reaction with system, pre-
catalyst mixed or
applied
separately.
Rapid curing.
Gap-filling.
UV curable Acrylics or Chemical, by Rapid curing
epoxies exposure to
UV

radiation

The pros and cons of Adhesive bonded joints
Advantages Disadvantages
Bond is continuous Cycle time
Joint can’t be dismantled
Low stress concentrations easily
Low application force is Process uniformity may be

suitable for fragile or flexible difficult to achieve
materials

Unlike materials can be joined Joints are weak under peel or
cleavage loads

Can be applied to complex Possibility of environmental
forms stress cracking
Joint is sealed Possibility of spills and runs

Basic equipment is simple

Joints are strong in tension,
compression and shear
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