Effect of silica micro-powder dosage on the performance of organosilicon plastic joint sealing materials

In order to meet the sealing requirements for the joints in concrete panels in severely cold areas, we have developed an organosilicon plastic joint sealing material with excellent low-temperature resistance, using silicone resin as the raw material. The effect of silica micro-powder dosage on the performance of the organosilicon plastic joint sealing material was studied. The organosilicon plastic joint sealing material had the best comprehensive performance when the silica micro-powder dosage was 550 parts (based on 100 parts of silicone rubber). The material showed a flow-stopping length of 165 mm and a sagging degree of 1.3 mm. At a temperature of -40 ℃, the material exhibited a pinning degree greater than 200 (0.1 mm) and an elongation at break larger than 1000%. Importantly, no bond failure at the interface with the concrete was observed during the stretching process. The preparation of this material solves the problem of traditional materials hardening at -40 ℃ and provides -a new joint stopping and sealing material for the construction of concrete panel dams in alpine areas, both domestically and internationally.