Preparation And Laboratory Evaluation Of Water Swelling Rubber

Two types of water swelling rubber are prepared by two kinds of methods respectively: blending and graft modification. The affect of all the component have on the mechanical properties of WSR have been studied. Water sorption ability and repeated water sorption ability have been tested, laboratory experiment of the water swelling rubber as blocking agent was conducted.A kind of water swelling rubber with natural rubber as matrix has been prepared by blending. The affect of the dosage of sulfidizer, the content of compatilizer, content of water absorbing agent have on properties of WSR were investigated. The results showed that WSR with AM as water absorbing agent and STAM as compatilizer, achieved better mechanical properties and water absorption ability, and water absorption ability of WSR greatly increased with increasing PAM content, while mechanical properties decreased. The mechanical properties of WSR significantly decreased after swelling with water, compared with that before swelling with water, and the larger the water absorption ability, the faster the mechanical properties decreased. The microphase structure of WSR was shown by SEM.It was made by K2S2O8 with Na2S2O3 oxidation-reduction initiate system, acrylamide grafting natural rubber latex. The effect of initiator, reaction temperature, dosage of monomer and cross-linking agent on quantity graft rate, grafting efficiency, rate of water adsorption, water swelling capacity and repeated water adsorption property of the product was studied.The results have been showed that the effect of reaction temperature, dosage of initiator and monomer have obvious influence on water adsorption capacity, graft rate and efficiency. The condign technical methods of AM grafting on to NR was attained: reaction temperature is 35℃, K2S2O8/Na2S2O3 initiator system, the amount of initiator is 0.5%, cross-linking agent is 1.75×10-4mol. Acrylamide definitely grafted onto NR, which was proved by FTIR.The laboratory test of water swelling rubber as blocking agent was conducted. The result indicates that water swelling rubber prepared through blending has superior sealing characteristics which results from the excellent mechanical behavior.