本研究分為兩個部份,第一部分利用一般自由基聚合法聚合出以異丙基丙烯醯胺N-isopropylacrylamide為主體之共聚物高分子,因PNIPAAM本身為溫度敏感型高分子(LCST≒32℃)趨近於人體溫度且具有高度生物相容性,故被廣泛地研究成為應用層面最廣的智慧型高分子。本研究利用此特點與4-amino-2-methylene-4-oxobutanoic acid (IAM)之單體共聚合,結果表明添加IAM單體之比例越高LCST有明顯上升趨勢,可提高至LCST ≒45℃。 第二部分為改變環境pH值探討共聚物對酸鹼敏感之特性,因PNIPAAM本身只具溫度敏感性,不具酸鹼敏感性,經由加入IAM單體共聚改質後,可合成出同時具有溫度/pH型高分子,近年來可應用在醫藥方面,如控制藥物釋放、感測器等等之生醫材料。其中,本研究之Poly(NIPAAm-co-IAM)( Sample R-8)若在3%水溶液下,經由緩衝溶液改變為中性pH 7相變化溫度接近人體溫度為37.8℃。本研究使用共聚合之單體IAM由工業技術研究院(ITRI)之材料及化工研究所共同合作完成,為一新穎、實用性高之材料,結合了Acrylic acid之羧酸基與Acrylamide之胺基於一個分子上,利用共聚過後兩個不同性質之官能基來達到更好的溫度敏感性及酸鹼敏感性。
The study consists of two parts:First, a series of copolymers of NIPAAM were prepared with the method of radical solution polymerization. Poly(N—isopropylacrylamide) shows thermo sensitivity(LCST≒32℃) and favorable biocompatibility. It is widely used as a new kind of intelligent material. The monomers we used for the series of polymerization are N-isopropylacrylamide (NIPAAm) and 4-amino-2-methylene-4-oxobutanoic acid (IAM). The results show that when the amount of IAM increases, the LCST increases(LCST ≒45℃). Second, the study of polymer modified, a new intelligent hydrogel which can respond to temperature and pH changes was described. The 3wt% aqueous solution of poly(NIPAAm-co-IAM)( Sample R-8) exhibits a phase transition temperature was close to human body temperature (37.8℃) in the buffer solution of pH 7. As 4-amino-2-methylene-4-oxobutanoic acid (IAM) not only has hydrophilic acrylic acid but also has acrylamide, when IAM polymerized with NIPAAM, it became more thermo and pH sensitivity.