摘要
采用接出接枝(grafting from)合成策略,以含有苄基氯官能团的聚苯乙烯为大分子引发剂,碘化钾、高氯酸银和三氟甲磺酸银为活化剂,引发2-乙基-2-噁唑啉进行正离子开环聚合反应.通过傅里叶变换红外光谱和核磁共振氢谱测定共聚物组成及接枝量,通过透射电子显微镜研究共聚物的微观形态,并研究原位制备的共聚物/纳米银复合物的两亲性、热稳定性与生物性能.结果表明:通过可控正离子开环聚合方法可以设计合成不同接枝量的聚苯乙烯-g-聚(2-乙基-2-噁唑啉)两亲性接枝共聚物(PS-g-PEOX)及其与纳米银的复合物,其中PEOX接枝质量含量在8%~97%之间,依赖于单体浓度及活化剂用量;纳米银颗粒直径为5~10 nm,质量含量在0.1%~3.5%之间,依赖于含银活化剂的用量.两亲性接枝共聚物能形成明显的微观相分离结构,其微观形态与PEOX含量有关.支化的拓扑结构有利于提高PEOX的热稳定性.PS-g-PEOX两亲性接枝共聚物的亲水性随着PEOX含量增加而提高,当PEOX质量含量为97%时,水接触角(WCA)为24°,亲水性支链PEOX的存在使PS-g-PEOX具有对牛血清蛋白的抗吸附性能.PS-g-PEOX在水中能形成稳定且均匀的微/纳米胶束,质量含量为0.054%的PS-g-PEOX能使水/甲苯互不相容的两相形成稳定的微纳乳液体系.原位制备的共聚物/纳米银复合物对大肠杆菌有一定的抑菌性,在生物医用材料领域有潜在的应用前景.
Polyoxazolines have drawn much attention by researchers because of their hydrophilicity,good biocompatibility,non-toxicity.Chemical modification on polyoxazolines and their derivatives by grafting reaction with other synthetic polymer chains is one of the most important ways to improve the comprehensive properties of polyoxazoline materials.The novel amphiphilic polystyrene-g-poly(2-ethyl-2-oxazoline),PS-g-PEOX,graft copolymers were prepared through the combination of“grafting from”method and cationic ring-opening polymerization of 2-ethyl-2-oxazoline using the polystyrene bearing chloromethyl functional groups as the macroinitiator in the presence of activator,such as potassium iodide(KI),silver perchlorate(AgClO4)or silver trifluoromethanesulfonate(AgCF3SO3).The chemical structure and composition of PS-g-PEOX graft copolymers were confirmed by Fourier transform infrared spectroscopy(FTIR)and nuclear magnetic resonance(1H-NMR).The results show that the novel amphiphilic PS-g-PEOX graft copolymers with various PEOX grafting contents ranging from 8%to 97%could be synthesized by changing the feed ratios of monomer and activator.The silver nanoparticle(5–10 nm)content in a range from 0.1%to 3.5%was uniformly dispersed in the PS-g-PEOX graft copolymer matrix.The microphase separation of amphiphilic PS-g-PEOX graft copolymer/silver nanoparticle nanocomposite was observed and the microscopic morphology was related to PEOX contents.The hydrophilicity of the amphiphilic PS-g-PEOX graft copolymers and water contact angle(WCA)increased with PEOX content.And the WCA of PS-g-PEOX graft copolymer film with 97%PEOX content is 24°.What’s more,amphiphilic PSg-PEOX graft copolymers can form stable and uniform micro/nano micelles in water.The stable oil/water suspension can be produced by adding a small amount of PS-g-PEOX graft copolymer into the incompatible water/toluene mixed system.The topological structure which formed by introducing PEOX onto PS backbones is beneficial to improve the thermal stability of PEOX.The g
作者
窦灿煜
张彦君
张晨
吴一弦
Can-yu Dou;Yan-jun Zhang;Chen Zhang;Yi-xian Wu(State Key Laboratory of Chemical Resources Engineering,Beijing Laboratory of Biomedical Materials,Beijing University of Chemical Technology,Beijing 100029)
出处
《高分子学报》
SCIE
CAS
CSCD
北大核心
2019年第9期939-948,I0003,共11页
Acta Polymerica Sinica
基金
国家自然科学基金(基金号21574007)资助项目
