The effect of equilibrium moisture content (M~o) on the glass transition region of a cured unsaturated polyester resin has been studied. Variation of the accelerator content has been shown to result in different values of Mo~. The moisture sensitivity has been studied by comparing the rate of change of the glass transition temperature with equilibrium moisture concentration [dTf/dMool over a range of accelerator concentrations. Following the arguments in Part 11, it is demonstrated that variations in moisture sensitivity arise from differences in average crosslink density. The moisture dependence of the expansion coefficient can also be interpreted on the basis of a heterogeneous crosslink density, which results from the statistics of the addition copolymerization responsible for cure
Посилання на статтю:
Influence of heterogeneous crosslink density on the thermomechanical and hygrothermal properties of an unsaturated polyester resin: 2. Hygrothermal studies / P. M. Jacobst and F. R. Jones // Polymer. – 1993. – Vol 34. – P. 2122-2127.