In this work, a series of thermally responsive terpolymers of N-isopropylacrylamide (NIPA) with three different comonomer contents was synthesized, and their swelling behaviour was studied as a function of composition and temperature. Temperature-sensitive, random cross-linked terpolymers of NIPA were prepared from methyl methacrylate (MMA), N-tert-butylacrylamide (NTBA), and acrylic acid (AA) using a free radical polymerization method. In the synthesis of terpolymer hydrogels, N,N-methylene bisacrylamide (BIS) was used as cross-linkers and ammonium persulfate (APS) as initiator. The NIPA content of the monomer feed varied from 80 to 50 mol %, and other comonomer feed varied from 40 to 5 mol %. The swelling equilibrium of these hydrogels was studied as a function of temperature and hydrophobic and hydrophilic comonomer contents. The swelling properties of the polymers were investigated in pure water at temperatures from 10 to 80°C. All of the synthesized gels were found to be sensitive to temperature. Glass transition temperature analyses and thermal analyses of the synthesized hydrogels were studied. The volume phase transition temperature and the swelling equilibrium () values of NIPA-based hydrogels synthesized in different feed ratios and in varying monomer contents were found in the range of 17–52°C and 14–51 g H₂O/g polymer, respectively. The glass temperature () of the NIPA/AA/(MMA or NTBA) hydrogels synthesized with feed ratios of 50/40/10 was found to be 133 or 142°C, respectively. The initial and the end degradation that were determined for hydrogels at high temperatures indicated the quite good thermal stability of hydrogels. When the mass loss of the synthesized hydrogels was 50%, the temperatures were measured between 247 and 258°C.

中文翻译：

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不同亲水和疏水共聚单体对N-异丙基丙烯酰胺基水凝胶的体积相变温度和热性能的影响

在这项工作中，合成了具有三种不同共聚单体含量的一系列N-异丙基丙烯酰胺（NIPA）热响应性三元共聚物，并研究了其溶胀行为随组成和温度的变化。NIPA的温度敏感型无规交联三元共聚物是使用自由基聚合方法由甲基丙烯酸甲酯（MMA），N-叔丁基丙烯酰胺（NTBA）和丙烯酸（AA）制备的。在三元共聚物水凝胶的合成中，N，N-亚甲基双丙烯酰胺（BIS）被用作交联剂，过硫酸铵（APS）被用作引发剂。单体进料的NIPA含量为80至50mol％，而其他共聚单体进料为40至5mol％。研究了这些水凝胶的溶胀平衡与温度以及疏水性和亲水性共聚单体含量的关系。在纯水中在10至80°C的温度下研究了聚合物的溶胀性能。发现所有合成的凝胶均对温度敏感。研究了合成水凝胶的玻璃化转变温度分析和热分析。体积相变温度和溶胀平衡（）在不同的进料比和不同的单体含量下合成的基于NIPA的水凝胶的值分别在17–52°C和14–51 g H ₂ O / g聚合物范围内。玻璃温度（）的NIPA / AA /（MMA或NTBA）的水凝胶具有50/40/10进料比合成被认为是133或142℃，分别。在高温下确定的水凝胶的初始和最终降解表明水凝胶的热稳定性非常好。当合成水凝胶的质量损失为50％时，测得的温度为247至258°C。