Performance of SBS Dual Synergistic Modified Water‐Swellable Rubber

Acrylic acid (AA) and methyl methacrylate (MMA) were used to polymerize with styrene–butadiene–styrene (SBS) to prepare SBS‐g‐AA/MMA modified water‐absorbent composites. SBS and SBS‐g‐AA/MMA were blended to prepare water‐swellable rubbers (WSRs) with good compatibility, great cohesion, and high strength by constructing a dual synergistic modification system. WSRs can maintain stable water absorption performance during repeated water‐absorbent and dehydration experiments. The problems of poor compatibility and uneven dispersion between water‐absorbent and rubber components were solved. SBS‐g‐AA/MMA was an important factor to control the comprehensive properties of WSRs. This paper focused on the influence of SBS‐g‐AA/MMA on water‐absorbent swelling and mechanical properties of WSRs in deionized water and various salt solutions. WSRs with 30 phr content of SBS‐g‐AA/MMA showed good mechanical and water‐absorbent swelling properties. Water absorption was significantly improved with increasing content of SBS‐g‐AA/MMA, but mechanical strength significantly decreased. Increasing content of SBS‐g‐AA/MMA obviously increased weight loss of WSRs; weight loss reduced to 6.19%, but it still maintained excellent water‐absorbent stability and reusability.