Abstract:

Antimicrobial gels based on biomass represent a significant category of polymeric materials with a diverse range of applications such as tissue engineering, drug delivery and wound dressings. In this paper, graphene/gelatin/carboxymethyl chitosan gels (GR/GEL/CMCS) were prepared by in-situ polymerization using gelatin and carboxymethyl chitosan as the raw materials and a highly stabilized graphene-PVP dispersion as the filler with the objective of achieving an excellent comprehensive performance. The structure and morphology of the gels were characterized with SEM, FT-IR, XRD and Raman spectroscopy. The influence of graphene on thermal as well as electrical conductivity of the gels were investigated using a thermal constant analyzer and electrochemical workstation. The mechanical and antimicrobial properties of the gels were also tested. The results showed that with the addition of grapheme, the thermal conductivity of the gels increased by 875.72%, reaching 1.05W/(m·K), and the electrical conductivity increased by 213.82%, reaching 0.03S/cm. Additionally, the gels indicated noteworthy antibacterial properties and improved tensile strength. The in-situ polymerization process facilitated the wrapping of graphene by PVP, thereby enhancing the wettability of graphene in water. Furthermore, the formation of covalent bonding interactions between the PVP molecules and the gel matrix enabled the orderly arrangement of graphene within the gel system, which in turn led to a notable improvement in the performance of the bio-based gels.

Key words: gels, gelatine, carboxymethyl chitosan, graphene, thermal conductivity, electrical conductivity

摘要：

基于生物质来源的抗菌凝胶是一类重要的功能高分子材料，在组织工程、药物缓释、伤口敷料等领域具有重要用途，但这类凝胶的导热和导电性能有待改进。以明胶和羧甲基壳聚糖为原料，高稳定石墨烯-聚乙烯吡咯烷酮（PVP）分散液为填料，采用原位聚合方式制备了石墨烯/明胶/羧甲基壳聚糖生物基凝胶（GR/GEL/CMCS），采用SEM、FT-IR、XRD和Raman光谱表征凝胶的结构，采用热常数分析仪和电化学工作站研究了凝胶的导热及导电性能，并研究了凝胶的力学和抗菌性能。结果表明，添加石墨烯的生物基凝胶热导率最高可提高875.72%，达到1.05W/(m·K)，电导率最高可提高213.82%，达到0.03S/cm。凝胶具有优异的抗菌性能，拉伸强度也得到改善。PVP提高了石墨烯在水中的浸润性，并与凝胶高分子网络相互作用，使石墨烯在凝胶中有序排列，改善了生物基凝胶的导热及导电性能。

关键词: 凝胶, 明胶, 羧甲基壳聚糖, 石墨烯, 导热性能, 导电性能