Study Of Preparation Of Water Swelling Rubber Made By Blending

Water swelling rubber(WSR) is a kind of new special rubber with excellent elasticity and absorptivity. It can be used widely as caulking, sealing of gap and water-prove materials. In view of cost and quality, WSR is normally produced through mechanical blend. The water absorption ability of WSR is depend on the characteristic of water-absorbent agent, expansivity properties of matrix, the compatibility of water absorbing agent and matrix material and so on. In this paper, the preparation of NR-g-MMA, NR/LDPE TPE, WSR used NR and NR/LDPE TPE as matrix were studied, and the mechanic properties and water absorption ability of WSR prepared.With oil-soluble CHP-TEP system as initiator, NR-g-MMA was produced by the methods of emulsion polymerization. The dependence of graft rate and efficiency on the dosage of initiator, reaction temperature and proportion of feed stock were investigated. The condign technical methods of MMA grafting onto NR was attained: the dosage of initiator was 0.6% by weight of graft monomer, the molar ratio of NR and MMA was 3/4, the reaction temperature was 45℃. The formation of graft copolymer was confirmed by means of IR. Then, the effect of NR-g-MMA on properties of WSR with NR/LDPE as matrix was studied when used as compatibilizer.NR/LDPE TPE was prepared by blending NR, LDPE and compatibilizer. The effect of NR/LDPE ratio, the temperature of blending, kinds and content of compatibilizers on mechanical properties of TPE was studied. The condign technical methods was: the ratio of NR and LDPE was 70/30, the temperature of blending was 120～130℃, the dosage of vulcanizer was 2.5 while the ratio of S and DCP was 2/3, the content of LDPE-g-MAH which was used as compatibilizer was 2. When all the compounding aid except vulcanizer were blended with NR, and then, blended with LDPE and dynamic vulcanized, TPE could achieve better mechanical properties.A water swelling rubber with NR as matrix has been prepared by blending. The effect of PEG, the dosage of vulcanizer, the content of compatibilizer, kinds and content of water absorbing agent on properties of WSR were investigated. The results showed that the addition of PEG increased the water absorption ability of WSR, but decreased the mechanical properties of WSR. WSR with PAANa as water absorbing agent and STAM as compatibilizer achieved better mechanical properties and water absorption ability, and water absorprion ability of WSR greatly increased with increasing PAANa content, while...