水凝胶是一种具有三维网络结构的新型功能高分子材料。 水凝胶因其可注射性、 良好的组织相容性、 无毒副作用、 在生物体内可降解性、 环境敏感性广泛用于药物释控、 吸附材料、 仿生工程、 光纤传感、 组织工程、 智能穿戴等方面。 水凝胶的传感主要是随着外界环境因素的改变, 引起溶胀度的不同, 导致水分子填补凝胶内部孔洞的程度不同, 呈现出水凝胶整体折射率变化的过程。 为了研究不同的溶胀度对水凝胶折射率的影响, 以壳聚糖为原料, 以过硫酸铵, N,N-亚甲基双丙烯酰胺分别作为引发剂和交联剂, 与丙烯酸接枝反应, 在氮气的环境中以化学方式制备壳聚糖水凝胶。 通过设计测量结构、 搭建实验平台, 检测了壳聚糖水凝胶的溶胀特性并对凝胶的溶胀度进行了标定; 以卤钨灯作为光源, 通过光谱仪检测了壳聚糖水凝胶透射光谱; 运用光在介质面传播特性与光波的偏振性原理, 对壳聚糖水凝胶透射光谱进行分析, 研究了不同溶胀度下壳聚糖水凝胶折射率的变化规律, 发现了不同溶胀度下凝胶对不同波长光波的折射能力存在差异性; 通过对数据的处理, 计算了波长为400 nm时, 凝胶折射率随溶胀度变化的范围及灵敏度Q1。 通过对实验数据的拟合, 得出了壳聚糖水凝胶折射率对溶胀度、 波长的响应规律且拟合度较高, 为壳聚糖水凝胶在光学传感方面的应用提供了实验基础。 通过实验, 说明了壳聚糖水凝胶有着优秀的溶胀特性、 较宽的折射率变化范围及较高的灵敏度, 在智能穿戴、 仿真皮肤、 光学传感等领域的应用有一定的优势。

Hydrogel is a new functional polymer material with a three-dimensional network structure. Hydrogels are widely used in drug release control, adsorption materials, biomimetic engineering, fiber optic sensing, tissue engineering, smart wear and other aspects, due to its injectability, good histocompatibility, non-toxic side effects, biodegradability in vivo, and environmental sensitivity. The sensing of the hydrogel is mainly caused by the change of external environment factors, causing the difference of swelling degree, which causes the water molecules to fill the inner pores of the gel to different extents, showing the process of the change of the overall refractive index of the hydrogel. In order to study the effect of different swelling degree on refraction index of the hydrogel, in this paper, chitosan was used as raw material, ammonium persulfate, N and N-methylenediacrylamide were used as an initiator and crosslinking agent respectively, and grafted with acrylic acid, and chitosan hydrogel was prepared chemically in a nitrogen environment. By designing the measurement structure and building the experimental platform, the swelling properties of chitosan hydrogel were tested, and the swelling degree of the gel was calibrated; the transmission spectrum of chitosan hydrogel was detected by spectrograph with halogen lamp as the light source; using the principle of light propagation on the surface of the medium and the principle of the polarization of light waves, the transmission spectrum of chitosan hydrogel is analyzed; the variation of the refractive index of chitosan hydrogel under different swelling degrees was studied, and it was found that the refractive power of gels with different wavelengths was different under different swelling degrees; through data processing, the range of gel refractive index change with the swelling degree and the sensitivity Q1 were calculated when the wavelength was 400 nm. By fitting the experimental data, the response law of refraction index of chitosan hydrogel to swelling degree and wavelength was obtained, and the fitting degree was higher, and it provides the experimental basis for the application of chitosan hydrogel in optical sensing. Through experiments, it is demonstrated that chitosan hydrogel has excellent swelling properties, wide range of refractive index variation and high sensitivity, it has certain advantages in intelligent wear, skin simulation, optical sensing and other fields.