polymers vulcanization

A studying of vulcanizing ability of the system zinc dibutyldithiocarbamate (ZDBC) - diphenylguanidine (DPG) - sulfur was carried out. It was established that films on the base of polyisoprene and composition polyisoprene : styrene-butadiene-styrene block copolymer (SBS) (polymers were taken in equal amounts) formed from a solution in toluene, in the presence of this system reached values of tensile strength 30-40 MPa and ultimate elongation 700-900 % during 0,5-1 hour at 70°C or 3-5 days at room temperature, simultaneously losing solubility in organic solvents. Under the same conditions homogeneous jelly-like structures were formed in toluene solutions of these polymers. The vulcanization process is supposed of having non-radical character due to lack of compounds in the system that are able to generate active free radicals causing cross-linking of macromolecules, as well as the incapability of anti-radical agent 2,6-di(tert-butyl)-4-methylphenol (used as an antioxidant in many polymer products) to inhibit the vulcanization process even in significant amounts (1 and 2 percent per polymer additively). This system can be used to produce films that are curing already during the drying process, as well as for polymer coating of materials that are undesirable to be exposed to high temperatures.

Posted by: Andrew Odin, The system for low-temperature vulcanization., Research Institute of Synthetic Rubber, Russian Federation (17-Nov-2022)
Follow Us
F Twt Li YT