亲水链段长度对液晶模板水凝胶形态和温敏性的影响  

EFFECT OF HYDROPHILIC SEGMENT LENGTH OF LIQUID CRYSTAL TEMPLATES ON THE MORPHOLOGY AND THERMAL RESPONSIBILITY OF HYDROGELS

作　　者：张青松[1] 彭喆[1] 张库[1] 陈莉[1] 赵义平[1] 

机构地区：[1]天津工业大学材料科学与工程学院中空纤维膜材料与膜过程省部共建国家重点实验室培育基地,天津300387

出　　处：《高分子学报》2013年第7期841-848,共8页Acta Polymerica Sinica

基　　金：国家自然科学基金(基金号21104058;31200719和21174103);天津市应用基础及前沿技术计划项目(项目号12JCQNJC01400)资助项目

摘　　要：采用疏水烷基(C16H33)相同而亲水的聚氧乙烯链(CH2CH2O)n=2,10,20长度不同的表面活性剂苄泽(Brij 52/56/58)作为模板制备得到3种孔洞尺寸为5～80μm的聚异丙基丙烯酰胺水凝胶(HNB).研究表明,n值越小,疏水性越大.15 wt%浓度下,不同n值的Brij水溶液均呈现明显的液晶织构.在t=4和7 min时HNB58和HNB56凝胶预聚液的透光率迅速下降至3.3～3.5,而HNB52凝胶预聚液的透光度一直保持在3.5.以n=20的Brij 58作为模板制备的HNB58凝胶孔洞数量多,尺寸为5～10μm.以n=2的Brij52为模板制备的HNB52凝胶孔洞形态呈层状,溶胀度最小,为6.9 g/g.而以n=10的Brij56为模板制备的HNB56凝胶孔洞呈蜂窝状,尺寸最大,为40～80μm,溶胀度最高,为7.9 g/g,37℃下20 min时HNB56失水超过80%.由于模板的作用,n值的变化并没有改变HNB凝胶的体积相转变温度(VPTT≈33℃),但吸热峰面积变宽.Three kinds of polyisopropylacrylamide hydrogels （HNB） with 5 ~ 80 υm of pore size were prepared by using surfactants Brij 52/56/58 with same hydrophobic alkyl chain C16H33 and different hydrophilic poly（ethylene oxide） （PEO, （CH2 CH2O）n=2,10.20） segments as template. The results show that the hydrophobicity increases with decreasing n values. The Brij aqueous solutions with different n values show clear liquid crystal texture at a concentration of 15 wt%. At t =4 and 7 min,the transmittance of HNB58 and HNB56 pre-polymerized liquids decreases to 3.3 ~ 3.5. However,the transmittance of HNB52 pre-polymerized liquid keeps at 3.5 throughout the reaction time. The HNB58 hydrogel using Brij 58 （n = 20） as template shows numerous pores, and the size is 5 - 10 υm. The HNB52 hydrogel using Brij 52 （n = 2） as template shows layered pore structure, and the maximum swelling ratio is 6.9 g/g. The HNB56 hydrogel using Brij 56 （n = 10） as template presents honeycombed state,having largest pore size from 40 to 80 υm. In addition,the maximum swelling ratios of HNB56 is 7.9 g/g,and water loss rate exceeds 80% at 37℃and 20 min. Since the template action of Brij, the volume phase transition temperature （ VPTT ≈33℃ ） of HNB hydrogels keeps almost the same in spite of the difference of n value, but the endothermie peak area becomes wider with increasing n value.

关 键 词：水凝胶 N-异丙基丙烯酰胺 模板 表面活性剂 温敏性 

分 类 号：O648.17[理学—物理化学]