膜乳化法制备尺寸均一P(NIPAM-co-AAc)微球及其羧基分布  

Distribution of Carboxyl Groups in Monodispersed Poly(N-Isopropylacylamide-co-Acrylic Acid) Microspheres Prepared by Membrane Emulsification

作　　者：司天保[1,2] 秦佳[3] 王玉霞[1] 马光辉[1] 

机构地区：[1]中国科学院过程工程研究所生化工程国家重点实验室,北京100190 [2]中国科学院研究生院,北京100049 [3]内蒙古工业大学化工学院,内蒙古呼和浩特010051

出　　处：《过程工程学报》2011年第2期343-348,共6页The Chinese Journal of Process Engineering

基　　金：国家自然科学基金资助项目(编号:20706053;20804048);国家重点基础研究发展规划(973)基金资助项目(编号:2009CB724705)

摘　　要：采用膜乳化法,以环己烷和氯仿混合溶液为油相,在室温下通过加入加速剂TEMED引发聚合反应,制备了一系列不同丙烯酸含量的P(NIPAM-co-AAc)微球.结果表明,在压力2kPa、环己烷/氯仿体积比7:3、第一和第二阶段过膜搅拌速度分别为140和170r/min的条件下,可制备粒径均一、大小可控、重复性较好的P(NIPAM-co-AAc)微球.用电导滴定法测定微球中羧基分布,所有不同丙烯酸含量的P(NIPAM-co-AAc)微球电导滴定曲线均为4阶梯形状,随其含量增加,微球外层羧基含量和内层包埋的羧基含量均逐渐增加,但外层羧基占总羧基含量比例先增大然后趋于不变,丙烯酸含量为15%时达最大值.Temperature-/pH-responsive monodispersed poly（N-isopropyl acrylamide-co-acrylic acid） [P（NIPAM-co-AAc）] microspheres were prepared by Shirasu porous glass membrane emulsification at room temperature with N,N,N＇,N＇-tetramethylethylenediamine as accelerator and cyclohexane/trichloromethane mixture as oil phase.The monodispersed P（NIPAM-co-AAc） microspheres with controllable diameter could be reproducibly obtained with cyclohexane-trichloromethane mixture（volumetric ratio 7：3） as oil phase and two stage stirring speeds（140 and and 170 r/min） under the membrane emulsification pressure of 2 kPa.Conductometric titration was used to determine the distribution of carboxyl groups in the microspheres.Four-step titration curves of all the P（NIPAM-co-AAc） microspheres with different acrylic acid contents were obtained.With the increase of AAc content,the amounts of both exterior carboxyl and embeded carboxyl groups increased gradually,but the percentage of exterior carboxyl groups increased firstly,then remained at a fixed value.The highest percentage of exterior carboxyl groups was obtained with 15%（ω） acrylic acid in the microspheres.

关 键 词：P(NIPAM-co-AAc)微球 电导滴定 羧基 膜乳化法 

分 类 号：TQ050.425[化学工程]