AMPS和丙烯酸共聚合反应及应用研究

【作者】 朱学文；

【导师】 廖列文；

【作者基本信息】 广东工业大学 ， 应用化学， 2002， 硕士

【摘要】 高吸水性树脂是交联型聚合物，能吸收比自身重几百倍甚至上千倍的水，广泛用于个人卫生用品、建筑、污水净化、农业抗旱保墒等行业。本文在综述高吸水性树脂的合成及应用的基础上，较为系统地研究了以丙烯酸和AMPS（2-乙酰胺基-2-甲基丙磺酸）为单体，采用水溶液聚合法、微波催化聚合法等进行高吸水性树脂合成的研究，研究表明，以AMPS和AA为单体，采用水溶液聚合法合成得到的高吸水性树脂，具有耐盐性能高，吸液倍数大等特点。实验的主要内容包括： 以AMPS和工业丙烯酸为单体，N,N’—亚甲基双丙烯酰胺为交联剂、过硫酸钠为引发剂，水溶液合成法合成得到高吸水性树脂，考察了单体浓度、交联剂用量、引发剂用量等因素对树脂吸水性能的影响，并对树脂吸液性能进行了研究。结果表明，在优化的合成条件下、树脂的最大吸水倍数达525g/g，吸0.9％NaCl溶液79g/g。树脂具有优良的耐盐性能。 通过数学拟合对树脂对水和不同盐溶液的吸收和保持性能进行了研究，对其耐盐性能进行了初步探讨。 为了获得性能更好的高吸水性树脂，以AMPS和减压蒸馏丙烯酸为单体，在单因素试验的基础上选择丙烯酸中和度、引发剂用量、单体摩尔比和交联剂用量为因素，进行L₉（3⁴）四因素三水平的正交试验，确定了最佳聚合工艺：丙烯酸的中和度为90％，单体mol比AMPS：AA=15：85，引发剂和交联剂的用量分别为单体总质量的0.025％和0.05％，在优化合成条件下，树脂的最大吸水倍数达990g/g，吸0.9％NaCl溶液128g/g。 进行了微波催化合成高吸水性树脂的尝试，考察了微波炉功率、微波加热时间等因素对树脂吸液性能的影响。研究表明：微波功率、微波加热时间直接影响聚合反应进程。在优化的条件下，合成得到的高吸水性树脂的最大吸水倍数可达400g/g以上，但总体性能比不上以水溶液法合成得到的高吸水性树脂。 用膨胀计对水溶液法合成高吸水性树脂的反应动力学进行了研究，结果表明，聚合反应的动力学方程为：r∞K[I]⁰.57[AMPS]¹.14[AA]⁰.86，聚合反应的活化能为123kJ·mol-1，聚合反应遵循一般的游离基加聚反应机理。更多还原

【Abstract】 Super absorbents are hydrophilic crosslinked polymers which can imbibe huge amounts of water. They are used mainly as absorbents in healthcare, communication technology, building industry, chromatography, water purification, and agricultural applications. On the basis of surveying super absorbents’ synthesis and application inside and outside country, a series of super absorbents was synthesized by means of aqueous polymerization and microwave catalysis polymerization with 2-acrylamido-2-methylpropane sulfonic acid (AMPS) and acrylic acid (AA) as raw materials. The study showed that the super absorbent synthesized by copolymerization of AMPS and acrylic acid by means of aqueous polymerization has excellent anti-salt performance and can absorb a large amount of water. The main contents of experiments were as follows:A series of super absorbents were synthesized by means of aqueous polymerization with industrial grade acrylic acid and AMPS as raw materials, N,N’-methylenebis-acrylamde as cross linker and potassium persulfate as initiator. The influence of such factors as mol ratio of monomer, crosslinker concentration, initiator concentration, neutralization of AA, ignite temperature was discussed in detail. The results showed that super absorbent synthesized under optimize terms can absorb water as high as 525 g/g and 0.9% NaCl solution 78 g/g. Experiments show that the resin has excellent anti-salt performance.Research on the super absorbent’s water and different salt solution absorbing and retaining capability was studied by mathematical fit. At the same time the resin’s anti-salt performance was discussed initially.To acquire better performance absorbent, vacuum distillated acrylic acid was used as raw material, and four factors affecting absorbent’s performance were selected to proceed L9(34) orthogonal experiments on the basis of mono-factor test. The optimization factors were determined to be: acrylic acid neutralization: 90%; monomer mol ratio AMPS:AA=15:85; amount of crosslinker: 0.025% of totalmonomers; amount of initiator: 0.05% of total monomers. The results showed thatsuper absorbent synthesized under optimize terms can absorb water as much as 990 g/g and 0.9% NaCl solution 128 g/g.Still super absorbent synthesized by microwave catalysis polymerization was attempted. Experiments showed that power of microwave oven and microwave heating time can obviously affect super absorbent’s performance. Absorbent that can absorb as high as 400 g/g water was obtained but the performance was not better than the resin synthesized by aqueous solution polymerization.The kinetics of copolymerization of AMPS and AA was studied by using dilatometer. Experiments showed that the kinetics equation of comolymerization AMPS and acrylic acid r[I]057[AMPS]"4[AA]086 . The reaction activity energy is about 123kJ-mor’. The mechanism of copolymerization of AMPS and acrylic acid follows mechanism of free radical.更多还原