Kinetics of photopolymerization of acrylates studied with a cure monitor and photoDSC

Photopolymerization of a number of neat acrylate monomers used in polymer coatings of optical fiber was studied with photoDSC and with a cure monitor using a fluorescent probe. Acrylates had functionality from one to six. PhotoDSC results show that conversion of monomers ranges from 40 to 100% depending upon functionality and structure of a monomer. Kinetics of hardening of a sample under light at ambient temperature was nicely fit into two-exponential law; rate constants k1 and k2 in this empirical analysis are in the range 0.5 - 35 min-1. Dependence of rate of polymerization and conversion upon functionality of a monomer is discussed. Both cure monitor and photoDSC can be successfully used for testing of liquid coatings. It was demonstrated, that an application of a moderate permanent magnetic field increases rate of cure of coating up till 20%.