Preparation And Properties Of Water Swelling Hydrogenated Butadiene-acrylonitrile Rubber

Superabsorbent materials are organic materials with hydrophilic polymer chains and lightly crosslinked three-dimensional structure possessing high to very high swelling capacity in aqueous media, which can still keep water under stress. Water swelling rubber(WSR) is a new water-absorbing material with novel mechanical performance, which is blended with super absorbent resin and rubber. With swelling and rubber elastic property, the material can be applied to a variety of irregular gap to seal water. Therefore it can be used widely as caulking, sealing of gap and water-prove materials in many place, for example building, subway and tunnel. Under room temperature, WSR can get a high expansion ratio in water, but not in hot water. However, due to the complex application environment, especially, in high temperature, improving WSR's heat resistance is important to its particular application.This thesis mainly contents: the preparation of amphiphilic porous water absorbent resin, water and oil absorption of resin; the preparation of WSR with hydrogenated butadiene-acrylonitrile rubber(HNBR), aging resistant property and hot water absorbing stability.In the work, free-radical copolymerization of acrylic acid(AA) with lauryl methacylate(LMA) can be successively utilized for the synthesis of water-soluble polymers. This polymer based on solution polymerization was prepared by ammonium persulfate(APS)and sodium hydrogen sulfite(NaHSO3) as redox initiator and N,N-methylene bisacrylamide(BIS) as crosslinking agent, calcium carbonate(CaCO3) as foaming agent, sodium carboxymethyl cellulose(CMC)as stabilizer. The copolymers were characterized by thermal gravity analysis(TG) and scanning electron microscope(SEM). The swelling of polymers in deionized water, different PH aqueous solution and diesel oil respectively were also investigated. It was found that CaCO3 and LMA had great influence on porosity, morphology of the porous structure and the rate of water and oil absorption. The material composed with nLMA/nAA=1/8, nCaCO3/nAA=1/2 had the best performance.Heat resistant WSR was prepared using HNBR. The materials were characterized by torque rheometer, vulcameter, tensile testing machine. The swelling of WSR in 25?, 60?, 85? water were also investigated. It was found that Carbon Black(CB), White Carbon Black(WCB) and dicumyl peroxide(DCP) had great influence on property of WSR.With the increase of the amount of WCB, the tensile strength and the hardness of the WSR gradually increased, stability of absorbing water in high temperature decreased gradually. WSR, containing 35 phr WCB, had the best mechanical properties and heat resistance properties.While the amount of CB increased, the crosslinking density, tensile strength and elongation at break of the WSR gradually decreased, the hardness of the WSR gradually increased. Besides, the hot water swelling stability decreased with the increase of the amount of CB. And the WSR contained CB has great aging resistance, especially the WSR contained 30 phr CB. WSR, containing 10 phr WCB, had the best hot water swelling stability and the lowest mass loss rate after absorption.With the increase of the amount of DCP, the crosslinking density, and tensile strength of the WSR gradually increased, and the cure time, elongation at break of the WSR gradually decreased. Also, the swelling rate and the swelling ratio of WSR decreased with the increase of the amount of DCP. WSR, contained 2 phr DCP, had the best aging resistance properties.