CHANGES IN THE NETWORK STRUCTURE OF NATURAL RUBBER VULCANIZATES UNDER SERVICE CONDITIONS.

In the reported experiments, the authors have studied changes in the network structure of both gum and filled natural rubber vulcanizate subjected to different laboratory tests like tensile, heat build-up, abrasion, compression set and flexing with the hope that these tests will simulate at least a few service conditions. It is expected that knowledge of such structural changes will help in predicting the behavior of rubber during prolonged use. The authors have chosen a semiefficient vulcanization system. They have also used mixes containing lignin for comparison against mixes without lignin. Previously De and coworkers have shown that lignin (in the form of sodium lignosulfonate) can be used as a cheap plasticizer in rubber.