利用乳液聚合法制备了PNIPAm智能水凝胶与具有温敏、pH值敏感特性的PNIPAm/AAc水凝胶.利用SEM、粒度分析对制备样品的物相结构、形貌进行了测试表征,表征结果显示聚合物具有单分散性,且聚合物微球具有良好的温敏性,其最低临界相变温度为31℃.进而考察了PNIPAm、PNIPAm/AAc与人血清白蛋白(HSA)的结合率情况,结果表明,PNIPAm共聚了丙烯酸(AAc),相互交联的高分子链间作用增强,聚合物分子呈收缩状态,高分子的空间网状结构变得致密.当温度和pH值发生变化时,对HSA结合率也发生相应地改变.当温度低于LCST温度时,PNIPAm/AAc构造发生改变,链内收缩导聚合物疏水,降低了对HSA结合率的影响.当碱性逐渐增强时,分子链中的氨基增多,它会与PNIPAm分子链上的官能团发生氢键作用,因此HSA的结合率呈现增加趋势.%In this article,the PNIPAm and PNIPAm/AAc with thermo-sensitive and pH-sensitivewere synthe-sized.The structures and properties of the composite were characterized bySEMandparticle size analyzer.The results showed that the as-prepared materials exhibited a well monodispersity.The relationship of diameter and temperature was detected,and the result showed that the microspheres had temperature-sensitive property with the lowest critical solution temperature(LCST) about 31 ℃.PNIPAm/AAc has the properties ofthermo-sensi-tive and pH-sensitive.The influence of pH and temperature on binding rate of the PNIPAm and PNIPAm/AAc were investigated.It was indicated that the mutual cross-linking of the polymer chain increased through PNI-PAmcopolymerized with AAc.PNIPAm/AAc was contraction state,making the polymer space network struc-ture become dense.When the temperature was lower than the LCST,the structure of PNIPAm/AAc changed, and the contraction of the polymer in the chain was hydrophobic,which reduced the effect on the binding rate of HSA.When the pH increased,the free amino groups in the molecular chain increased,leading to forming the hydrogen bonds in the PNIPAm chain,which increased the binding rate of HSA.
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