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以4-乙酰基丙烯酰乙酸乙酯（AAEA）、丙烯酸（AA）以及PVA为原料，通过自由基溶液聚合法，制备了PVA-P（AAEA-CO-AA）半穿网络型（s-IPN）水凝胶．红外分析表明，AAEA主要以烯醇式结构存在，并且由于PAAEA，PAA以及PVA之间较强的氢键作用，使得PAAEA以及PVA分子上的C-O伸缩振动吸收峰移向了低波数处．电镜分析表明，PVA能贯穿于P（AAEA—CO—AA）交联网络中，从而有效阻碍凝胶的相分离；而XRD研究发现，当PVA用量较少时，PVA能均匀的贯穿于凝胶网络中，形成完善的互穿网络结构，当PVA用量过高时，PVA不能有效地贯穿于聚合物交联网络中而出现结晶．采用DSC对s-IPN水凝胶的体积相转变进行了研究，结果表明，该s-IPN水凝胶的体积相转变温度（VPTT）在54．0至57．8℃之间，并且随着PVA用量的增加，凝胶的VPTT逐渐升高．研究了该s—IPN水凝胶的抗压缩性能，结果表明，PVA与P（AAEA—CO—AA）形成的半互穿网络结构能有效提高凝胶的抗压缩强度，其最大抗压缩强度可达8．4MPa．对凝胶的温度敏感性研究发现，当外界温度低于VPTT时，凝胶能保持溶胀状态；而当温度高于VPTT时，凝胶的平衡溶胀度迅速下降，表现为温度敏感性．“,”Semi interpenetrating polymer networks （s-IPN） hydrogels composed of poly（vinyl acohol） （PVA）, poly（4-acetyl acryloyl ethyl acetate-co-acrylic acid） [P（AAEA-co-AA）] were synthesized via solution polymerization using acrylic acid （AA）, 4-acetyl acryloyl ethyl acetate （AAEA） and PVA. Foutier-transform infrared （FT-IR） was used to confirm the chemical structure of the s-IPN hydrogels. The resuits showed that the AAEA mainly existed as enol form, making the peak of C--O stretching in the IR spectra of PVA-P（AAEA-co-AA） flow to low wave numbers. This is attributed to the formation of strong hydrogen bonds between PVA, PAA and PAAEA. SEM macrographs revealed that PVA impenetrated into the P（AAEA-co-AA） ploymer networks homogeneously, and barricaded the phase separation of the hydrogels. XRD analyses showed that the hydrogels formed perfect s-IPN structure when the dosage of PVA was low. However, when the dosage of PVA was high, PVA could not impenetrate in P（AAEA-co-AA） ploymer networks homogeneously, making the crystallization of PVA increase significantly. The volume phase transition temperature （VPTT） of the s-IPN hydrogels was determined by their respective DSC ther- mograms of swollen hydrogel specimens. The results showed that the VPTT of the hydrogels ranged from 54.0 to 57.8℃, and increased with the increasing dosage of PVA. The stress strength of s-IPN hydrogels was studied, the results showed that the s-IPN structure formed between PVA and P（AAEA-co-AA） improved the strength of the hydrogels significantly, and the maximum stress strength of the hydrogel was about 8.4 MPa. The temperature sensitivity of the s-IPN hydrogels was also investigated, the results showed that the hydrogels exhibited excellent temperature sensitivity. When the temperature was lower than VPTT, the hydrogels kept at a swelling state, but when the temperature was higher than VPTT, the hydrogels des- welled evidently.