Synthesis of Thermo-responsive Poly(N-isopropylacrylamide) Hydrogels by rontal Polymerization
The synthesis of thermo-responsive hydrogels poly (Nisopropylacrylamide) (PNIPA) via frontal polymerization (FP) was carried out in four mixed solvents, i.e. dimethylsulfoxide (DMSO) mixing with water, ethanol, tetrahydrofuran (THF) and acetone, respectively. The obtained samples were characterized and compared in term of their yield, thermo-response behavior and microstructure. It was found that the application of mixed solvent didnt compromise the thermo-responsive feature of PNIPA hydrogels. All the samples underwent a drastic swelling transition at about 32 ℃ in aqueous solution. Furthermore, the category and content of the solvent of lower boiling point caused remarkable difference in features of PNIPA hydrogels. The sample prepared in DMSO/water mixed solvent was characterized by die highest yield and the lowest font temperature (Tmax) and velocity (Vf), whereas one synthesized in DMSO/THF mixture exhibited the smallest yield and the highest front temperature. Solvent composition influenced the porous morphologies of the samples remarkably and, consequently their water swelling capability. The novel honeycomb cells were observed in PNIPA hydrogel synthesized in DMSO/THF, their big size being responsible for the higher swelling ratio as compared to ones synthesize in the others mixed medium. The sample obtained in DMSO/water solvent showed the lowest swelling ratio due to the highest crosslink degree among these prepared in DMSO/water, DMSO/ethanol and DMSO/acetone mixture. Also, increasing the relative amount of lower-boiling-point solvent in mixed solvent led to a decrease in frontal temperature and an improvement in swelling capability of the hydrogel.
Frontal polymerization Thermo-response Poly (N-isopropylacrylamide) Hydrogel
Qiao Feng Qingzhi Yan Changchun Ge
Laboratory of Special Ceramics and Powder Metallurgy, University of Science and Technology Beijing,Beijing 100083
国际会议
The 2nd Asian Materials Database Symposium(第二届亚洲材料数据库会议 AMDS 2010)
三亚
英文
287-297
2010-03-10（万方平台首次上网日期，不代表论文的发表时间）