Thermoset

The curing process transforms the resin into a Plastic or Rubber by Cross-link ing. Energy and Catalyst s are added that cause the molecular chains to link into a rigid, 3-D structure. A thermoset material cannot be Melt ed and re-molded after it is cured.

Thermoset materials are generally stronger than Thermoplastic materials, and are also better suited to high- Temperature applications. They do not lend themselves to Recycling like Thermoplastics , which can be melted and re-molded.

EXAMPLES

Vulcanized Rubber

Bakelite , a Phenol Formaldehyde Resin (used in electrical insulators and plastic wear)

Duroplast

Urea-Formaldehyde Foam (used in Plywood , particleboard and medium-density fibreboard)

Melamine (used on worktop surfaces)

Polyester Resin (used in glass-reinforced plastics/Fibreglass ( GRP ))

Epoxy Resin (used as an adhesive and in Fibre Reinforced Plastic s such as glass reinforced plastic and Graphite-reinforced Plastic )

METHODS USED TO MOULD THERMOSETS

Injection Moulding (used for objects like milk bottle crates)

Extrusion Moulding (used for making pipes, threads of fabric and insulation for electrical cables)

Calendering (used for making large sheets of plastic)

Compression Moulding (used to shape most thermosetting plastics)

Blow Moulding (used for bottles)

Information About

Thermoset