ABSTRACT In this paper, two-step cross-linking method was used to prepare a composite hydrogel. Explore the effects of the mass ratio of polyvinyl alcohol to sodium alginate, the concentration of cross-linking agent and the times of freeze-thaw cycle on the strength and self-healing properties of hydrogels. The hydrogel were characterized by Infrared Spectroscopy, X-ray Diffraction and Environmental Scanning Electron Microscopy,the water absorption capacity was evaluated bythe swelling rate and the tensile strength was measuered by Electronic Universal Testing Machine. The results indicated that when the mass ratio of PVA and SA was 30:1, the concentration of sodium tetraborate solution was 10wt%, and freeze-thaw cycle once composite hydrogel had the best comprehensive performance: its maximum tensile strength reached 0.90 MPa, and it has good self-healing performance which can be proved by that its tensile strength could return to 75% of initial level 24 hours after being cutting off.

中文翻译：

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高强度自修复水凝胶的制备与表征

摘要 本文采用两步交联法制备复合水凝胶。探讨聚乙烯醇与海藻酸钠的质量比、交联剂浓度和冻融循环次数对水凝胶强度和自愈合性能的影响。采用红外光谱、X射线衍射和环境扫描电子显微镜对水凝胶进行表征，通过溶胀率评价吸水能力，用电子万能试验机测定拉伸强度。结果表明，当PVA与SA的质量比为30:1时，四硼酸钠溶液的浓度为10wt%，冻融循环一次的复合水凝胶综合性能最佳：其最大拉伸强度达到0.90 MPa，