以聚环氧乙烷(PEO)作为聚氨酯的软段,六亚甲基二异氰酸酯作为聚氨酯的硬段,同时引入偶氮生色团,通过聚合反应制备得到两亲性的聚氨酯类共聚物,并在溶液中通过自组装制备了聚氨酯纳米粒子。所有聚合物的结构都通过红外光谱、核磁共振氢谱进行了表征。通过紫外光谱和动态光散射测定了聚合物纳米粒子的相转变行为和尺寸,研究了其对于温度、紫外光照等外界刺激的响应性。聚合物纳米粒子的相转变温度分别在56~71℃,平均粒径在20~40nm,紫外光照后纳米粒子粒径增大。% A series of novel amphiphilic PU-AZO copolymers containing soft segment polyethylene oxide (PEO), hard segment hexamethylene diisocyanate and azo chromophore have been prepared by a convenient method. PU-AZO copolymers can be directly dispersed in aqueous solution as uniformly sized nanoparticles. The chemical structures of PU-AZO copolymers were characterized by IR and 1HNMR. The phase transition behavior and particle size were studied by ultraviolet (UV) spectrum and dynamic light scattering (DLS). The responses to temperature and UV light were investigated as well. The results showed that these polymeric nanoparticles possess a multistimuli response. The phase transition temperature was 56–71℃ and the average diameter was 20–40 nm. The size of nanoparticle increased after UV irradiation.
展开▼
