Polymers
1.0 Introduction
2.0 Polymers and polymerization
3.0 Free-radical vinyl polymerization
4.0 Ionic Polymerization
5.0 Natural Rubber
6.0 Synthetic Rubber
7.0 Polyvinyl Chloride (PVC)
8.0 Teflon or PTFE (Polytetrafluoro ethylene)
9.0 Nylon-66
4.1 Cationic Polymerization
It is initiated by acids. Isobutylene, for example, undergoes cationic polymerization to a tacky material used in adhesives. Copolymerization with a little isoprene gives butyl rubber, used to make automobile inner tubes and tire liners. A variety of acids can be used: sulfuric acid; $AlCl_3$ or $BF_3$ plus a trace of water.
