Examples Using IR Fibre Optics

Isobutylene polymerisation initiated by 1,2-epoxy-2,4,4-trimethylpentane (TMPO-l)/TiCl4 was studied using IR fibre optics. The initiating mechanism involves the formation of tertiary carbocations, by both SNi and SN2 paths. From the linearity of the first-order plots of monomer consumption, and the near uniformity of the polyisobutylene, it was concluded that living polymerisation conditions prevailed (i.e., no termination step) (32). The ATR head can monitor very low concentrations (0.1 mmol/1) (49). 

A linear-chained epoxy resin was formulated from phenyl glycidyl ether and nadic methyl anhydride, catalysed by benzyldimethylamine (248). An IR fibre-optic probe was used to follow the conversion of a thermosetting tetrafunctional epoxy resin in which the hardener was an aromatic diamine and a carboxylic dianhydride. A polymerisation system consisting of a cycloaliphatic diepoxide, epoxidised natural rubber (ENR), glycidyl methacrylate (GMA) and a cationic photoinitiator, triphenylsulfonium hexafluoro-antimonate, was studied (75). Multifunctional epoxy/ amine formulations (Epon 825 plus 4,4 -methylene- 

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