The crosslinking reactions that occur in unsaturated polyester resins result in a heterogeneous structure of highly crosslinked domains separated by less highly crosslinked material. This structure is a result of the formation of gel particles, which are initiated at free radicals during the curing reaction. Controlling the concentration of free radicals present in the system enables the heterogeneity within the resin to be varied, and its influence on the thermomechanical properties to be studied.
Посилання на статтю:
The influence of heterogeneous crosslink density on the therrnornechanical and hygrotherrnal properties of an unsaturated polyester resin: 1. Thermomechanical response / P. M. Jacobs and F. R. Jones* // Polymer. – 1992. – Vol 33. – P. 1418-1422.