High and Low Temperature Resistance of Phenyl silicone rubber

Abstract

Methyl Phenyl and diphenyl silicone rubbers were synthesized from octamethyl cyclotetrasiloxane (D4), methylphenyl cyclosiloxane, octaphenyl cyclotetrasiloxane, etc. Compared with the commercial methylvinyl silicone rubber, the high and low temperature resistances of methyl vinyl silicone rubber were studied in this paper. The results showed that the introduction of phenyl groups can improve the thermal properties of silicone rubber, and the thermal stability of diphenyl silicone rubber is better than that of methyl phenyl silicone rubber. But there is little difference of mechanical properties in high temperature environment for three silicone rubber. DMTA analysis showed that there were still a small amount of crystals in diphenyl silicone rubber, while methylphenyl silicone rubber was amorphous rubber. The mechanical properties at low temperature indicated that the tensile strength of diphenyl silicone rubber was 4.1Mpa higher than that of methylphenyl silicone rubber at -70 °C due to the existence of low-temperature crystallization.

Al2O3 Nano filler’s impact on electrical, mechanical, thermal, microstructural and the chemical characteristics of liquid silicone rubber for composite insulators

“…This is because the phenyl pattern may inhibit main chain cross linking or degeneration presented mostly by the oxidative breakdown of the side chains, improving the silicone rubber’s thermal resilience. 21 Up to 245°C, pure LSR has a similar trend to the 5wt% Al 2 O 3 sample. Above this temperature, pure LSR exhibits just slightly greater thermal stability.…”

Preparation and characterization of diphenyl silicone rubber/microfiber glass wool composite thermal control films

“…This reduces the regularity and mobility of the molecular chain structure of the PSR and increases its energy consumption, thus effectively reducing its crystallinity. 33 Dispersion of MGW in PSR Fig. 6 displays the SEM images of the fracture surfaces of the PSR/MGW (5 wt%) and PSR samples at two different magnications.…”

Negative temperature coefficient and positive temperature coefficient behavior of electrically conductive silicone/carbon black composites

“…5 The reason for this wide range of applications are the unique material properties of the silicones like high thermal stability up to 300 °C, excellent low temperature flexibility or electrical insulating properties. 6,7…”

“…5 The reason for this wide range of applications are the unique material properties of the silicones like high thermal stability up to 300 °C, excellent low temperature flexibility or electrical insulating properties. 6,7 One promising, but so far less investigated application of electrically conductive silicones are flexible heating elements with self-regulating properties, which are defined by a positive temperature coefficient (PTC) or negative temperature coefficient (NTC).…”