PVL-PEG-PVL水凝胶紫外光固化动力学研究

Kinetics of UV-Curing of PVL-PEG-PVL Hydrogel

为了制备PVL-PEG-PVL水凝胶,并研究其紫外光固化动力学,本文采用熔融聚合法制备了PVL-PEG-PVL三嵌段共聚物,利用丙烯酰氯(AC)修饰并以2,2二甲氧基2苯基苯乙酮(DMPA)为引发剂在紫外光辐射下制备PVLPEGPVL水凝胶。采用红外光谱(FTIR)、扫描电镜(SEM)和万能试验机对水凝胶的结构和力学性能进行表征和测试,研究水凝胶紫外光固化动力学。实验结果表明:当凝胶前体浓度为0.06g·mL^-1、光引发剂含量为单体质量分数的0.5%、紫外灯工作电流为14A时,凝胶的固化速率最快,11min内交联度可达到93%。此条件下制备的凝胶力学强度最高,拉伸强度可达0.241MPa,断裂伸长率为1888.47%。

The paper studies the kinetics of the UV photopolymerization of PVL-PEG-PVL hydrogel.The PVL-PEG-PVL triblock copolymers were first prepared by melt polymerization,and then modified with acryloyl chloride(AC).And then PVL-PEG-PVL hydrogel was prepared under ultraviolet radiation with 2,2-Dimethoxy-2-phenylacetophenone(DMPA) as initiator. The structure and mechanical properties of the hydrogels were characterized and tested by Fourier transform infrared spectroscopy(FTIR),scanning electron microscopy(SEM) and a universal testing machine,on the basis of which the kinetics of UV photopolymerization was investigated.The results show that the gel curing rate was the fastest when the gel precursor concentration was 0.06 g·mL^-1,the photoinitiator content was 0.5% of the monomer mass fraction,and the working current of UV lamp was 14 A.The crosslinking degree of 11 min reached 93%.The mechanical strength of the gel prepared under these conditions was the highest,its tensile strength reached 0.241 MPa,and the elongation at break was 1 888.47%.