NIPAM单体及PEGDA/NIPAM共聚物的合成及表征

The synthesis and characterization of NIPAM monomer and PEGDA/NIPAM copolymers

采用烯腈烷基化再部分水解的方法合成的N-异丙基丙烯酰胺(NIPAM)单体,并利用红外光谱(FT-IR)、氢核磁共振谱(1HNMR)、质谱(MS)进行了表征。以IRGACURE2959为光引光剂,通过紫外光引发光聚合的方法合成了PEGDA/NIPAM共聚物水凝胶,并对共聚物进行FT-IR表征,探讨了凝胶的亲水性能。结果表明,NIAPM单体的FT-IR中含1657.7cm-1的羰基峰、1549.5cm-1氨基上的氢峰、1367.5cm-1的异丙基上的振动氢峰和1621.2cm-1的烯烃双键峰,1HNMR中含δH7.9亚胺基的活泼氢峰及双键中同碳位、顺式位和反式位的氢峰及异丙基特征峰,MS表明m/z=112为分子离子峰,结果符合NIPAM结构式;聚合物FT-IR表明,双键的特征峰减弱,双键打开合成了PEGDA/NIPAM共聚物;随着NIPAM单体含量的增大,共聚物的接触角减小,平衡溶胀率增大,亲水性增强。

The synthesis method of pure N-isopropylacrylamide （NIPAM） monomer was studied in this paper,which was alkylated alkene nitrile and then hydrolyzed.The properties of the synthesis monomer was investigated respectively by fourier transform infrared spectroscopy （FT-IR）,1H nuclear magnetic resonance （1H NMR） and mass spectrometry （MS）.The co-polymer hydrogels was synthesized by UV-initiated polymerization of poly（ethylene glycol ） diacrylate （PEGDA） and NIPAM,with IRGACURE2959 as an initiator.The polymer was investigated by FT-IR.And the hydrophilicity of the hydrogel was discussed with contact angle and equilibrium water content.The FT-IR showed that,1657.7cm-1 was CO peak,1549.5cm-1 was N—H peak,1367.5cm-1 was isopropyl C—H peak and 1621.2cm-1 was CC peak.The 1H NMR showed that δH7.9 was the active hydrogen peak of imino and distinguished the hydrogen peak from the gem-position,cis-position and trans-position of double bond.The MS showed that m/z 112 was the molecular ion peak.All of the above results was in line with the structure of NIPAM.The FT-IR of the PEGDA/NIPAM polymer showed that the double bond peaks was weak. With the double bond was opened,the PEGDA/NIPAM copolymers had been synthesized.The contact angle of the polymers decreased,the equilibrium water content increased and the hydrophilicity enhanced with the increasing of NIPAM monomer.