Abstract

Water-soluble photoreactive polymers with both phosphorylcholine and benzophenone groups were synthesized for the reaction between the polymers and the substrate in aqueous medium. To control the polymer architecture, the living radical polymerization method was applied to the copolymerization of 2-methacryloyloxyethyl phosphorylcholine and benzophenone methacrylates. These polymers possess various architectures, such as linear polymers, polymers with hydrophobic terminals, and 4-armed star-like polymers, that could promote their adsorption on the substrate surfaces. Additionally, two types of benzophenone groups were examined. Due to the bulky phosphorylcholine group, tetra(ethylene oxide) group as a spacer between polymer main chain and benzophenone group was considered. These polymers could adsorb on the surface in an aqueous medium, followed by reaction on the surface via photoirradiation depending on the chemical structure of the benzophenone group. The thickness of the polymer layer depended on the polymer architecture, i.e. a polymer with a hydrophobic terminal could form a thick layer. After modification, the contact angle by air in the aqueous medium decreased, compared to that on the base substrate. This was due to the hydrophilic nature based on the phosphorylcholine groups at the surface. The amount of proteins adsorbed on the surface also decreased because of the surface modification. These findings indicated that these water-soluble photoreactive polymers could be applied for the safer and effective surface modification of substrates via conventional photoirradiation without using an organic solvent.

摘要

合成了具有磷酰胆碱和二苯甲酮基团的水溶性光反应聚合物，用于聚合物与基质在水性介质中的反应。为了控制聚合物的结构，将活性自由基聚合方法应用于2-甲基丙烯酰氧基乙基磷酰胆碱和二苯甲酮甲基丙烯酸酯的共聚。这些聚合物具有各种结构，例如线性聚合物、具有疏水末端的聚合物和四臂星状聚合物，可以促进它们在基材表面上的吸附。此外，检查了两种类型的二苯甲酮基团。由于庞大的磷酰胆碱基团，四（环氧乙烷）基团被认为是聚合物主链和二苯甲酮基团之间的间隔基。这些聚合物可以吸附在水性介质的表面上，通过光照射取决于二苯甲酮基团的化学结构。聚合物层的厚度取决于聚合物结构，即具有疏水末端的聚合物可以形成厚层。改性后，水介质中空气的接触角与基底基板上的接触角相比有所降低。这是由于基于表面磷酸胆碱基团的亲水性。由于表面改性，吸附在表面上的蛋白质的量也减少了。这些发现表明，这些水溶性光反应性聚合物可以通过传统的光辐照，在不使用有机溶剂的情况下，用于对基材进行更安全有效的表面改性。