基于SAP吸水膨胀橡胶的耐温耐盐性能

以反相悬浮聚合法合成P(AANa/AMPS/DMDAAC)两性共聚高吸水树脂(SAP),并引发溶胀在SAP中的丙烯酸丁酯和丙烯酸进行原位共聚合,制备疏水改性高吸水树脂。将丁腈橡胶、改性高吸水树脂、补强剂和其他助剂借助混炼机混炼均匀,在硫化成型机上高温硫化制备吸水膨胀橡胶(WSR)。研究盐溶液种类、盐溶液浓度以及环境温度对WSR的质量吸水膨胀倍率的影响,并对吸水后的WSR进行热重分析。结果表明:盐溶液中阳离子浓度越大,化合价越高,对WSR吸水性能影响越明显,吸液膨胀倍率越小;在对WSR进行一系列不同温度下的吸液性能研究时发现,WSR在120℃具有较好的吸水膨胀性能。在环境温度达到175℃时,WSR达到失水平衡。

Study on Thermal/Salty Tolerance of SAP-based Water Swelling Rubber

Superabsorbent polymer (SAP) of P(AANa/AMPS/DMDAAC) was synthesized by inverse suspension polymerization.Hydrophobic modification of this SAP was performed via in-situ polymerization with introduced monomer n-butyl acrylate and acrylic acid.Water swellable rubber (WSR) was prepared using modified SAP, NBR, reinforcing agent and other additives.The swelling ratio in mass of WSR in water or in aqueous solutions of diverse inorganic salt was measured.The effects of ionic concentration and temperature on the swelling ratio were investigated and thermogravimetric analysis (TGA) of swollen rubber was performed.The results showed that the swelling ratio of WSR remarkably decreased with higher ions valence and with increasing concentration of salt solution.The highest swelling rate was obtained at 120℃, both in water and in 0.9%NaCl solution.A water loss plateau of swollen WSR was observed with 0.9% NaCl solution as the absorbent solution.