Hydrogels can be used as seawater desalination, sewage treatment, and as drug carriers in medical treatment. In this paper, pure water, acrylic acid and acrylamide are used as raw materials, and the hydrogel is made under the irradiation of gamma ray. The hydrogel is placed in a beaker containing pure water for swelling test, placed in an air dryer for drying test, and placed under a xenon lamp light source in the solution of pure water, salt water and sewage for evaporation test. This experiment compress the prepared hydrogel with weights of different weights, and then cut the prepared hydrogel into small strips of the same length with scissors for tensile test. In the high concentration hydrogel, the drying and swelling rate is slower than that of the low concentration hydrogel. The low concentration hydrogel is the fastest, and the slowest is the hydrogel added with graphite. Under the irradiation of xenon lamp light source, different hydrogels have different water loss properties. In the same solution, graphite has the fastest evaporation rate, while the evaporation rate of high concentration hydrogels is slower. In the tensile test, the hydrogel added with graphite stretched longer. In the compression experiment, the high concentration hydrogel is softer and has stronger compression performance. In the photothermal evaporation experiment, this kind of hydrogel also showed an excellent evaporation rate after adding graphite powder. The hydrogel prepared in this paper has good swelling property and seawater desalination performance, which can be used for seawater desalination and sewage treatment. I would devided into 4 parts to summarise the result of the experiment.

Shunzhi He, Zhuxu Zhou. The Concept of Preparation and Swelling of Hydrogel. Academic Journal of Materials & Chemistry (2024) Vol. 5, Issue 3: 117-124. https://doi.org/10.25236/AJMC.2024.050318.

[1] Zou, X., Li, Y., Xu, K., Wen, H., Shen, Z., & Ren, X. (2018). Microalgae harvesting by buoy-bead flotation process using Bioflocculant as alternative to chemical Flocculant. Algal research, 32, 233-240.

[2] Jeldres, R. I., Piceros, E. C., Leiva, W. H., Toledo, P. G., & Herrera, N. (2017). Viscoelasticity and yielding properties of flocculated kaolinite sediments in saline water. Colloids and Surfaces A: Physicochemical and Engineering Aspects, 529, 1009-1015.

[3] Zhang, F., Tang, Y., Liu, H., Ji, H., Jiang, C., Zhang, J., ... & Lee, C. S. (2016). Uniform incorporation of flocculent molybdenum disulfide nanostructure into three-dimensional porous graphene as an anode for high-performance lithium ion batteries and hybrid supercapacitors. ACS Applied Materials & Interfaces, 8(7), 4691-4699.

[4] Zhao, H., Cao, G., Chen, H., Li, H., & Zhou, J. (2017). Evaluation of hemocompatibility and hemostasis of a bioflocculant. Colloids and Surfaces B: Biointerfaces, 159, 712-719.

[5] Guo, G., Wu, Q., Liu, F., Yin, J., Wu, Z. L., Zheng, Q., & Qian, J. (2022). Solvent‐cast‐assisted printing of biomimetic morphing hydrogel structures with solvent evaporation‐induced swelling mismatch. Advanced Functional Materials, 32(2), 2108548.

[6] Fujiyabu, T., Li, X., Chung, U. I., & Sakai, T. (2019). Diffusion behavior of water molecules in hydrogels with controlled network structure. Macromolecules, 52(5), 1923-1929.