The Synthesis Of Super Absorbent Polymer And Water Swelling Rubber Preparation

Water Swelling Rubber (WSR) is functional polymer materials whichis rising from1970s and widely used in a variety of engineering andpipeline construction deformation joint seals and other areas, is ofconsiderable value in our life and industries. Currently, the WaterSwelling Rubber were mainly prepared by polyacrylic acid-based SuperAbsorbent Ploymer(SAP) and rubber matrix with physical mixingmethods, those issues such as water-absorbent and rubber matrixincompatibility, when used, the water-absorbent precipitation, lead toabsorption and mechanical properties decreasing apparently. So far, lotsof improved methods have been used,including such as adding additivesin rubber at manufacturing process; Modifying the SAP so thatwater-absorbent can mixed with rubber more closer by physical orchemical interactions; Finding new SAP alternative to traditionalhydrophilic absorbent material, eta. The objective of these methods is tomake the performance of WSR best.Four types of WSR were prepared based on the modified SAP andother new preparation methods:1. Adding methyl glycidyl ester of acrylic(GMA) when prepared SAP,then the WSR was prepared byphysical blending method.2.Adding acrylic acid(AA) and beta hydroxyethyl methacrylate(HEMA) in proportion to prepared copolymer,againthrough chemical connecting branches of swell prepared rubber.3. Usingthe new material hydrophilic polyethylene glycol(PEG) through thecoupling agent(it has the characteristics of polyurethane structure) graftedto the preparation of rubber matrix WSR.4. Using the methyl allylpolyoxyethylene ether(TPEG) that can sulfide connected directiy to thebase rubber to prepared WSR. SAP and WSR was investigated by thermalanalysis, infrared spectrum analysis(IR),and other ways. The waterabsorption performance and mechanical properties of rubber were testedalso. At the same time, the performance of the SAP and WSR wasevaluated synthetically.The results indicated that:1.Using the hydrogen peroxide andascorbic acid as the redox initiator system, the SAP is stability and hashigh water absorbing capacity. The absorption of SAP reducessignificantly when added GMA or HEMA, but in the preparation of WSR,with appropriate content, the SAP can raise rubber vulcanizationcrosslinking degree and the best addition is nGMA/nAA=2.0%andnHEMA/nAA=10.0%.The SAP has good performance according to thethermal analysis and water retention performance.2. Through theinvestigation to the performance of the polyurethane(PU) which prepared by PEG or allyl polyethylene glycol(APEG) with the method of one stepfound that PEG is better than APEG.3. Four methods tests of WSRshowed: The WSR’s comprehensive performance is best when thevulcanization is highest. Overall, the comprehensive performance ofWSR prepared by chemical grafting significantly better than thatprepared by physical blending method, added pre polymers PEG-TDI isbetter than that added SAP which has been modified to prepare WSR. Atthe same time, the introduction of polyurethane structure can improve theWSR’s mechanical properties and performance.4. Though theexploration to the WSR prepared with new hydrophilic substances(TPEG), found that finding a new hydrophilic material preparation toprepare WSR is an effective and feasible method and the future objectiveis to make the methods and process become simplify.Comprehensive, the methods of physical blend and chemical graftingboth can improve the “incompatible” problems between the hydrophilicmaterial and rubber. But the chemical grafting method is better thanphysical blending method.