no links between polymer chains. they can get re shaped over and over again also they are recyclable
thermosetting:
can not be changed after being moulded once so they are hard to recycle
Summary of plastics
good thermal and electrical insulators
good straight against weight ratio
doesnt decompose
low melting point
available in wide range of coulers and transparancy
two main catagories thermoplastic and thermosetting
Ways to improve properties of plastics
Fillers: fillers are used to bulk up plastics to make them stronger for lower cost.
Flame retardents: used to reduce the risk of combustion
Anti static agents: reduces the effect of static charges
Plasticisers: makes material less brittle and improves the flow properties
Stableisers: reduce the effect the ultra violet light has uppon the object
Close loop production
Types of thermoplastics
ABS - Acrylonitrile butadiene styrine
CA - Cellulose acetate
NYLON - Polyamide
PMMA - Acrylic
PP - Polypropalene
HIPS - High impact polystyrene
PS - Polystyrene
LDPE - Low density polyethylene
HDPE - High density polyethylene
UPVC - Polyvynal chloride
PVC - Unplasticated flexible polyvynal chloride
PET - Polyetheylene terepheluate
PC - Polycarbinate
Types of thermosetting plastics
Epoxy resins: surface coating, adheasives
Malamine formaldahide: table ware, decorative laminates
Polyester resins: castings
Urea fomaldahide: electical fittings, adheasives
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