Preparation And Application Of Water-Swelling Rubber

Water-sellable rubber is a novel functional material. SAP was added to rubber in thismaterial. Therefore, this material not only maintains the excellent mechanical properties andelasticity of rubber, but also has the capability of water absorbing. This product has a dualseal performance, they are elastic and swelling. WSR has good applicable prospect and hugemarket demand. It can be used in waterproof of building, subway and tunnel. It also can beused in oilfield, medical etc.In this thesis, we select SBR as the basic materials, PAAS as absorbent material,prepared by mechanical blending method. The effects of the mass of PAAS, the kind andamount of reinforcing agents, the mass of SMA, PEG, NBR have been separate studied. Thefollowing properties were studied:swelling rate,final swelling rate,mass loss rate, tensilestrength, elongation at break. Furthermore, the microcosmic structure was studied by SEM.Tests show, the swelling capability enhanced with the increase of the amount of PAAS,however, the mechanical properties decreased. An appropriate amount of SMA can improvethe compatibility very well. The amount and type of packing has some impact on theabsorption and mechanical properties. This paper attempts to replace black carbon withWCB or Calcium Carbonate，and also attempts to using WCB and Calcium Carbonatetogether to replace CB. Mixed with calcium carbonate or silica in rubber can improveswelling capacity,but made the mechanical properties decrease.The swelling capabilityenhanced with the increase of the amount of PEG, however, the mechanical propertiesdecreased. This paper attempts to partially replace SBR with NBR,experiments show that,adding the right amount of NBR can effectively improve the expansion ratio.In order to verify the actual use of the product, this paper studies the effect of variousconcentration of NaCl,MgCl2and CaCl2solution on swelling capacity of WSR.And alsostudies the effect of various concentration of H2SO4,NaOH solution on capacity of WSR.Experiments show that, the product can get the largest swelling rate when immersed in purewater. When in the same solution,the larger the ion concentration，the less the capacityability. Divalent ions influence serious than monovalent ions. Acidic solution and alkalinesolution can also decrease the swelling capacity. And the more acidic or alkaline,the less thecapacity ability. This paper has studied the reversible extent the Salt ions have created. Experimentsshow that: after soaking in a salt solution six hours, then wash the product three times withpure water and put them in pure water,the produce’s swelling capacity nearly not break bysalt ions. This show, within a certain period of time, the inhibitory effect of salt ionson theswelling is reversible inhibition.