摘要
通过共溶剂-乳化-溶剂挥发法制备了聚乙烯醇(PVA)分散螺吡喃(SP)光致变色有机凝胶薄膜(PDPGSP),采用双子型表面活性剂六亚甲基-1,6-双十二烷基二甲基溴化铵(Gemini)调控聚合物/有机凝胶界面相互作用,系统研究了薄膜光致变色行为、褪色行为、微观结构形貌、力学性能及耐疲劳性能.结果表明,PDPG-SP薄膜表现出良好的光致变色行为与类溶液的褪色行为,SP在薄膜中褪色速率与聚丙二醇(PPG)溶液相近;薄膜具有优异的力学性能,其弹性模量与拉伸强度分别高达~547和~23.5 MPa;经过10次变色-褪色循环后,薄膜最大吸收波长处吸光度A衰减了约35%,相比以PVA1为表面活性剂(衰减约53%),耐疲劳性明显提升.Gemini有序聚集过程中头基分离力的有效阻抑,抑制了PVA/有机凝胶界面对SP的锚定,使更多SP分子分布于自由异构的有机凝胶微环境,提高薄膜褪色速率,同时可逆异构分子数量的增加,使薄膜耐疲劳性提高.
Polyvinyl alcohol（ PVA） dispersed spiropyran（ SP） organogel thin film（ PDPG-SP） was prepared by a facile co-solvent-evaporation strategy. 1,6-Didodecyl（ dimethyl） azanium bromide hexamethylene used to regulate interface interaction between PVA/organogel was used as one sort of Gemini surfactant. The photochromic and fading behavior, microstructure morphology, mechanical properties and light fatigue resistance of PDPG-SP were investigated. The results show that the thermal decay behavior for PDPG-SP film is similar to that of SP/PPG solution. Interestingly,PDPG-SP also has excellent mechanical property with elastic modulus and tensile strength as high as ca. 547 and ca. 23. 5 MPa respectively. After 10 repeated coloration-discoloration cycles,the intensity at the maximum absorption wavelength decreases by about 35%,which was decreased dramatically comparing with that using PVA1 as a surfactant（ ca. 53%）. Based on the separation force by head-end gathering process of Gemini,the anchor effect of PVA/organogel interface on SP is suppressed. Meanwhile,more SP molecules were protected within micro-solvent environment,which was homogeneously dispersed in PVA matrix. The anchor effect increases the number of SP molecules that could conduct reversible free isomerization,accelerating the fading rate and improving the fatigue resistance of the PDPG-SP thin film concurrently.
作者
龙世军
陈明敏
赵友姣
王小涛
李学锋
廖永贵
LONG Shijun;CHEN Mingmin;ZHAO Youjiao;WANG Xiaotao;LI Xuefeng;LIAO Yonggui(School of Materials and Chemical Engineering;Hubei Provincial Key Laboratory of Green Materials for Light Industry, Hubei University of Technology, Wuhan 430068, China;School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan 430074, China)
出处
《高等学校化学学报》
SCIE
EI
CAS
CSCD
北大核心
2018年第5期1078-1083,共6页
Chemical Journal of Chinese Universities
基金
国家自然科学青年基金(批准号：51603065)
湖北省教育厅青年人才项目(批准号：Q20151406)资助
