Rheological Comparison of Silicone Rubber Crosslinking with Platinum Catalysts and Triethylamine, Methanol & Ethanolamine Solvents

The control of silicone rubber’s viscoelastic properties namely loss factor, storage and loss moduli during crosslinking are crucial as its malleable behaviour changes differently under different conditions and affecting the final product. Hence, it becomes the objective of this study to investigate the rheological behaviour of silicone rubber cured under different formulation ratios with platinum catalysts and triethylamine, methanol & ethanolamine solvent. Measurement was conducted for the silicone rubber to crosslinker ratios of ۲.۵:۷.۵, ۵:۵, ۷.۵:۲.۵ and ۱۰:۱ at different elevated temperatures, and for the silicone rubber with triethylamine, methanol and ethanolamine at different angular frequencies. While the crossover of storage and modulus curve which signifies a gel point was not observed at higher ratios of platinum used across the temperature range of ۲۵ – ۱۰۰°C, it was found at ۸۹°C and ۹۵°C with the formulation ratios of ۱۰:۱ and ۷.۵:۲.۵, respectively. On the other hand, the crossover point was observed for silicone rubber at ۱۰۰ s-۱ for triethylamine, ۳ s-۱ and ۱۰۰ s-۱ for methanol, and ۷۰ s-۱ alongside ۲۹۰ s-۱ for ethanolamine. The presence of gel point indicates that crosslinking of silicone rubber successfully took place and this study proves that controlling the crosslinking behaviour was possible.

کلیدواژه ها:

silicone rubber ، storage modulus ، loss modulus ، crosslink ، glass transition temperature ، rheological measurement