Table 1.

Structure of amorphous and semi-crystalline thermoplastic polymers.

Amorphous Polymers	Semi-Crystalline Polymers
Distinctive Properties
Random molecular arrangement	Orderly molecular arrangement
Broad softening temperature/glass transition temperature (Tg)	Sharp melting point (Tm)
Easy to thermoform	Difficult to thermoform
Rigid polymers	Soft polymers
Tough, Rigid, Good Creep and Chemical Resistance	Excellent Chemical Resistance
Transparent look	Opaque look
e.g., Acrylonitrile butadiene styrene (ABS), Acrylic, polycarbonate, polystyrene, Polyvinyl chloride (PVC)	e.g., Nylon, Polyethylene terephthalate (PET), Polybutylene terephthalate (PBT), Polyether ether ketone (PEEK), polyethylene