化工学报 ›› 2008, Vol. 59 ›› Issue (11): 2805-2811.

• 催化、动力学与反应器 • 上一篇    下一篇

聚(N-异丙基丙烯酰胺-co-丙烯酸)水凝胶对铜离子的体积响应动力学

赵祯霞;李忠;徐金方;夏启斌   

  1. 华南理工大学传热强化与过程节能教育部重点实验室;广东省绿色化学品技术重点实验室,华南理工大学化工与能源学院
  • 出版日期:2008-11-05 发布日期:2008-11-05

Volumetric shrinking kinetics of poly(N-isopropylacrylamide-co-acrylic acid)hydrogels in response to Cu2+ solution

ZHAO Zhenxia;LI Zhong;XU Jinfang;XIA Qibin   

  • Online:2008-11-05 Published:2008-11-05

摘要:

采用微波辐射法制备了N-异丙基丙烯酰胺-co-丙烯酸共聚水凝胶,探讨了该水凝胶对Cu2+的响应动力学,并估算出此过程中水凝胶的体积收缩速率常数及其反应活化能,同时建立了Cu2+浓度对水凝胶体积收缩响应速率常数影响的数学关系模型。实验结果表明,水凝胶对Cu2+所产生的体积收缩响应符合拟一级动力学反应。在40~60℃水溶液中,水凝胶的收缩速率随溶液中Cu2+浓度的增高而加快,其反应活化能在36~42 kJ•mol-1之间,且随着溶液中Cu2+浓度的增大而逐渐减小。重复性实验表明,该共聚水凝胶经过3次体积收缩(50.0℃溶液)/溶胀(6.0℃溶液)的循环实验,它在含Cu2+水溶液中对温度变化仍能保持高灵敏度的体积收缩/溶胀响应,而且其3次体积收缩/溶胀响应值几乎一样,有很好的重现性。

关键词:

聚(N-异丙基丙烯酰胺-co-丙烯酸);体积收缩响应;反应动力学, 体积恢复再生

Abstract:

The copolymer (N-isopropylacrylamide-co-acrylic acid, NIPAAm-co-AA) was synthesized by the microwave irradiation method and its volumetric shrinking kinetics in Cu2+ aqueous solution was investigated in this paper.The volumetric shrinking kinetic constants and the activation energies for these copolymer hydrogels were estimated from their kinetic data.Furthermore, a mathematic model was established to describe the relationship between Cu2+ concentration and volumetric shrinking kinetic rate constant of copolymer hydrogels.The results indicated that the volumetric shrinking kinetics of these copolymer hydrogels was found to follow the pseudo-first-ordered kinetics.Moreover, their volumetric shrinking kinetic rate increased with increasing Cu2+ concentration in solution.Their response activation energies in the range of 36-42 kJ•mol-1 decreased with increasing Cu2+ concentration at a temperature between 40—60℃.The regeneration experiment showed that the copolymer hydrogels could shrink/swell in response to temperature-swing in Cu2+ solution sensitively after shrinking (at 50.0℃)/swelling (at 6.0℃) for three times continuously.The tiny change of their shrinking/swelling ratio in the regeneration experiment showed a good repetition of hydrogel in response to temperature.

Key words:

聚(N-异丙基丙烯酰胺-co-丙烯酸);体积收缩响应;反应动力学, 体积恢复再生