Surface modification of versatile polymeric materials without changing their bulk properties is one of the essential techniques for regulating their physical and chemical characteristics, and this technique can improve the functions of materials. In this study, a bottlebrush-type poly[oligo(2-ethyl-2-oxazoline) methacrylate] (P[O(Ox)nMA]) (n = 7 and 19) was synthesized as a surface modifier. This compound was mixed into poly(methyl methacrylate) (PMMA) as a matrix (PMMA/P[O(Ox)nMA]) with a weight ratio of 15%, and the aggregation state in the surface region was examined under air and aqueous environments via atomic force microscopy, contact angle measurement, angular-dependent X-ray photoelectron spectroscopy, and neutron reflectivity. The surface of the PMMA/P[O(Ox)nMA] films was flat at the subnanometer level and covered with the PMMA-rich phase. However, once the films contacted water, the surface was reorganized due to the migration of P[O(Ox)nMA]. The extent of the surface segregation was more remarkable for P[O(Ox)7MA] than P[O(Ox)19MA] due to the entropic factor. Concurrently, NIH3T3 fibroblast adhesion and serum protein adsorption on the film were more strongly suppressed for P[O(Ox)7MA] than P[O(Ox)19MA] because it formed a thicker diffused interface in the film with water. As a surface modifier, poly[oligo(2-ethyl-2-oxazoline) methacrylate] (P[O(Ox)nMA]) with two different degrees of polymerization (n = 7 and 19) of the side chain were mixed into poly(methyl methacrylate) (PMMA). Once the PMMA/P[O(Ox)nMA] films contacted with water, the surface was reorganized due to the migration of P[O(Ox)nMA]. The extent of the surface segregation was more remarkable for P[O(Ox)7MA] than P[O(Ox)19MA] due to the entropic factor, resulting that the fibroblast adhesion on the film were much better suppressed for P[O(Ox)7MA] than P[O(Ox)19MA].

中文翻译：

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聚[低聚（2-乙基-2-恶唑啉）甲基丙烯酸酯]作为生物惰性的表面改性剂

在不改变其整体性质的情况下对多功能聚合物材料进行表面改性是调节其物理和化学特性的重要技术之一，该技术可以改善材料的功能。在这项研究中，合成了一种瓶刷型聚[低聚（2-乙基-2-恶唑啉）甲基丙烯酸酯]（P[O（Ox）nMA]）（n = 7 和 19）作为表面改性剂。将该化合物以 15% 的重量比混合到作为基质的聚甲基丙烯酸甲酯 (PMMA) (PMMA/P[O(Ox)nMA]) 中，并在空气和水下检查表面区域的聚集状态环境通过原子力显微镜、接触角测量、角度相关的 X 射线光电子能谱和中子反射率。PMMA/P[O(Ox)nMA] 薄膜的表面在亚纳米级是平坦的，并覆盖着富含 PMMA 的相。然而，一旦薄膜接触水，由于 P[O(Ox)nMA] 的迁移，表面就会重新组织。由于熵因子，P[O(Ox)7MA] 的表面偏析程度比 P[O(Ox)19MA] 更显着。同时，P[O(Ox)7MA] 比 P[O(Ox)19MA] 更强烈地抑制了膜上的 NIH3T3 成纤维细胞粘附和血清蛋白吸附，因为它在膜中与水形成了更厚的扩散界面。作为表面改性剂，将侧链具有两种不同聚合度（n = 7 和 19）的聚[低聚（2-乙基-2-恶唑啉）甲基丙烯酸酯]（P[O（Ox）nMA]）混合成聚(甲基丙烯酸甲酯) (PMMA)。一旦 PMMA/P[O(Ox)nMA] 薄膜与水接触，由于 P[O(Ox)nMA] 的迁移，表面会重新组织。