LCST and UCST in One: Double Thermoresponsive Behavior of Block Copolymers of Poly(ethylene glycol) and Poly(acrylamide-co-acrylonitrile)
LCST and UCST in One: Double Thermoresponsive Behavior of Block Copolymers of Poly(ethylene glycol) and Poly(acrylamide-co-acrylonitrile)
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DOI：
10.1021/acs.langmuir.5b02006
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发表时间：
2015-08-18
期刊：
影响因子：
3.9
通讯作者：
Agarwal, Seema
中科院分区：
文献类型：
--
作者：
Kaefer, Florian;Liu, Fangyao;Agarwal, Seema
通过引入聚乙二醇（PEG）嵌段，热响应行为从丙烯酰胺-丙烯腈共聚物（AAm-co-AN）的上临界溶液温度（UCST）型单相变转变为水中的双响应行为（LCST-UCST型（LCST，下临界溶液温度））。该聚合物是通过使用丙烯酰胺和丙烯腈进行自由基聚合以简单的方式合成的。聚乙二醇（PEG）大分子偶氮引发剂。根据 AAm、AN 和 PEG 的比例，在多种浓度下观察到双重热响应行为，可重复多次循环，且滞后非常小。静态光散射 (SLS) 和动态光散射 (DLS) 以及浊度光度测定和透射电子显微镜证实了由于从胶束到团聚体的形态变化随温度变化而产生的独特相变行为。低细胞毒性和二合一的热响应行为使得该聚合物在未来的生物医学应用中具有广阔的前景。
The change in thermoresponsive behavior from a single phase transition of upper critical solution temperature (UCST)-type of an acrylamide-acrylonitrile copolymer (AAm-co-AN) to a double responsive behavior (LCST-UCST-type (LCST, lower critical solution temperature)) in water by the introduction of a poly(ethylene glycol) (PEG) block is highlighted in the present work The polymer is synthesized in a simple way by free-radical polymerization of acrylamide and acrylonitrile using a poly(ethylene glycol) (PEG) macro-azoinitiator. The dual thermoresponsive behavior was observed in a wide range of concentrations repeatable for many cycles with very small hysteresis depending upon the ratio of AAm, AN and PEG. Static light scattering (SLS) and dynamic light scattering (DLS) together with turbidity photometry and transmission electron microscopy confirmed a unique phase transition behavior due to the temperature dependent change in the morphology from micelles to agglomerates. The low cytotoxicity and two-in-one thermoresponsive behavior makes the polymer promising for biomedical applications in the future.