Exotherm Curves: A Method for Obtaining Reproducible Curing Parameters for Radiation Polymerization of Vinyl-Divinyl Comonomers

Authors

  • M. M. Micko
  • L. Paszner

Keywords:

Polymerization, exotherm curves, activation period, acceleration period, gel effect point, cure, methyl methacrylate, divinyl monomer

Abstract

Polymerization parameters, suitable for both monitoring and comparative studies on catalytic and radiation polymerization of MMA/divinyl comonomers, are readily derived from time/temperature exotherm records. By geometric solution of exotherm curves Gel Effect Point (GEP), polymerization rate coefficients in Activation (PRCI) and Acceleration (PRCII), and total dose (D) became available for kinetic studies. Individual components of the exotherm curve, such as reciprocal of time required to attain maximum on the exotherm curve, provide information on the overall rate of cure (ORC). Reciprocal of the time required to reach GEP characterizes the efficiency of cross-linking agents to cause onset of the gel effect phenomena in comonomer systems.

Repeated measurements and statistical analyses of such data, derived from exotherms, show good reproducibility and a high degree of reliability, especially with systems exhibiting rather sharp maxima on the exotherm curve.

References

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Published

2007-06-05

Issue

Number 4 / Winter 1974

Section

Research Contributions

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