Abstract:

A composite structural hydrogel comprising a graphene oxide (GO) sheet, a poly(N-isopropylacrylamide) (PNIPAM) microgel sphere and a PNIPAM segment was designed and synthesized. Combination of the GO sheets and thermoresponsive PNIPAM microsphere polymeric networks provides the hydrogels with an NIR responsive property. The oxidized groups of GO nanosheets enable the formation of a hydrogen bond interaction with the amide groups of PNIPAM chains. PNIPAM microspheres in hydrogel improve the response rate and responsive swelling ratio. By changing the concentration of GO, synthesis time of the microsphere, concentration of N-isopropylacrylamide (NIPAM) and the propotion of microspheres and GO, the light and thermal sensitivity of the hydrogel can be enhanced. Compared to traditional PNIPAM hydrogel, such hydrogels are capable of responsing to light, achieving non-contact controlled deformation with high response speed and high degree of response, which may expand the scope of hydrogel applications, such as NIR-controllled switch, and provide enhanced performance.

Key words: nanomaterials, composite materials, polymer, graphene oxide, hydrogel

摘要：

设计合成了一种包含氧化石墨烯（GO）片层、聚（N-异丙基丙烯酰胺）（PNIPAM）微凝胶球体和PNIPAM链段的复合结构水凝胶。通过控制聚合时间得到负载双键且粒径不同的PNIPAM微凝胶，将其作为交联点与N-异丙基丙烯酰胺（NIPAM）聚合，GO作为纳米填料掺入水凝胶体系，GO片层上的含氧基团与NIPAM上的胺基产生氢键物理交联。此方法制备的复合水凝胶同时具有温度敏感和近红外光敏感特性，通过改变GO浓度、微凝胶的合成时间、NIPAM浓度等条件，水凝胶的光敏感性和温度敏感性得到提升。相比于传统PNIPAM水凝胶，此种复合水凝胶能够对光响应，实现非接触式控制形变，且响应速率快、响应程度高，可应用于光控开关等领域。

关键词: 纳米材料, 复合材料, 聚合物, 氧化石墨烯, 水凝胶