Plastics

Plastics

1. The history of plastic

   • the celluloid was patented in 1860
   • in 1907 one of the first synthetic polymers called Bakellite
   • during the war there was a shortage of natural materials such as skil, cotton, latex and wood
     • scientist in the countries involved started researching the production of new fibres
       • neoprene
       • butadiene

2. monomers and polymers

   • most polymers are formed from molecules called monomers
     • wich are duplicate and joined together to form a large chain structure
       • this process is called pollymerisation
         • elthylene
         • propene
         • chloroethene or vinyl chloride

3. types of plastic

   • thermoplastics
     • which are made up of long ,linear chains of polymers
       • PETE
       • HDPE
       • PVC
       • LDPE
       • PP
       • PS
       • OTHER
   • thermosetting polymers
     • which are made of three-dimensional interwoven polymer chains
       • bakelites
       • melamine resins
       • polyester resins
       • epoxy resins
       • polyurethanes
   • elastomers
     • which with a few exceptions are thermosetting polyners that, given a especific distribution of their branches, become highly elastic at room temperature
       • rubber
       • neoprene
       • silicone

4. plastic shaping techniques

   • 1.extrusion
   • 2.calendaring
   • 3.injection
   • 4.blow moulding
   • 5.compression
   • 6.vacuum forming
   • spin or rotational moulding