Effect of co-agent type on curing kinetics of vinyl-methyl siloxane and phenyl-vinyl-methyl siloxane elastomers

Authors : Davut Aksüt, Elif Kaymazlar, Murat Şen

Pages : 1-16

Doi:10.37094/adyujsci.1425531

View : 56 | Download : 65

Publication Date : 2024-06-28

Article Type : Research Paper

Abstract :This study investigated the effect of Type I co-agents Zinc Acrylate (ZDA), Zinc Methacrylate (ZDMA) and Type II co-agents Triallyloxy-1,3,5-triazine (TAC), and 1,3,5-triallyl-1,3,5- triazine (TAIC) on the curing kinetics of vinyl methyl polysiloxane (VMQ) and phenyl vinyl methyl polysiloxane (PVMQ) elastomers. 2,5-Dimethyl-2,5-di(tertiary-butylperoxyl) hexane (DBPH) was used as a crosslinker. The rheological analyses were performed with a Moving Die Rheometer (MDR) at four different temperatures. Cure curves were evaluated according to 1th and nth curing kinetics and curing rate constant (k), reaction degree (n), and activation energy (Ea) values were calculated. When the results were evaluated, it was seen that the k, rate constant increased with the addition of TAC, TAIC, and ZDA in the compounds, whereas the k, rate constant value decreased with the use of ZDMA. It is thought that the reason for this is that ZDMA forms a more stable 3° radical due to the methyl group in its structure. ZDA was found to be the accelerator that increased the cure rate of PVMQ and VMQ. When the activation energies obtained were examined, it was seen that the activation energies for PVMQ were higher than the energies obtained for VMQ. The reason for this was attributed stabilization of free radicals by the phenyl group in the structure of the PVMQ
Keywords : Activation energy, Co agent, Peroxide curing, Silicone elastomer