Impact of Raw Phenyl Silicone Rubber Parameters on ethod Vulcanized Phenyl Silicone Rubber

Abstract

Based on the structure of raw phenyl silicone rubber and performance of vulcanized rubber, the properties of raw and vulcanized phenyl silicone rubber are tested in this study. The relationship between raw rubber parameters and the influence of raw rubber properties on the performance of vulcanized rubber are also analyzed. Conclusions are as follows: (1) The viscosity average molecular weight of the raw silicone rubber measured by Ubbelohde viscometer and gel permeation chromatography (GPC) mdiffers relatively greatly, with the result of Ubbelohde viscometer higher than that of GPC. (2) The glass transition temperature of raw silicone rubber is significantly affected by the molar content of phenyl chain (phenyl content) in its structure. In a good linear relationship with phenyl content, it increases as the phenyl content increases. (3) The static glass transition temperature of raw rubber measured by differential scanning calorimetry (DSC) is 0-15 °C lower than the dynamic glass transition temperature measured by dynamic thermo-mechanical analyzer (DMA). (4) Mooney viscosity increases with the increase of the viscosity average molecular weight of raw rubber. (5) As phenyl content rises from 20 % to 40 %, the damping peak loss factor of vulcanized rubber increases from 0.4 to 0.7 and the damping peak temperature increases from -90 °C to -40 °C. (6) As the molar content of vinyl chain (vinyl content) is raised from 0.1 % to 0.6 %, the hardness of vulcanized rubber is boosted from 45 to 65, and the tensile strength decreases from 12 MPa to 6 MPa. (7) With the increase of vinyl content from 0.1 % to 0.4 %, the tear strength of vulcanized rubber decreases from 45 kN/m to 25 kN/m. (8) The vinyl content has an obvious impact on the damping performance of vulcanized rubber at high temperatures. When vinyl content increases from 0.1 % to 0.5 %, the damping property of the vulcanized rubber under high temperature drops from 0.25 to 0.1. (9) The compression set of vulcanized rubber decreases with the increase of vinyl content of raw rubber.