Abstract:

In this study, the solution blending method was used to explore the preparation of phytic acid/gelatin composite films by adding different proportions of phytic acid. The effect of different phytic acid content on the crystalline structure, microscopic morphology, transparency, swelling and mechanical strength of the composite film was tested, and then the structure regulation and performance improvement effect of phytic acid on the gelatin film were analyzed and explored. The results showed that compared with pure gelatin film, phytic acid had obvious crosslinking modification effect on gelatin. The composite film had a compact and uniform internal structure. Phytic acid inhibited the self-crystallization behavior of gelatin through the interaction of polar groups and reduced the crystallinity of the composite film. As the content of phytic acid increased, the visible light transmittance of the composite film decreased. The swelling rate changes indicated that the structural reorganization of phytic acid and gelatin can effectively block the penetration of water molecules. The mechanical strength of the composite film was increasing with the addition of phytic acid. When the mass fraction of phytic acid reached 10%, the tensile strength of the phytic acid/gelatin composite film was 61.57MPa, which was about 20% higher than that of pure gelatin (50MPa). However, it had no obvious effect on elongation at break.

Key words: phytic acid, gelatin, composite film, transmittance, swelling rate, mechanical properties

摘要：

采用溶液共混法，通过添加不同比例的植酸探索制备植酸/明胶复合膜，测试不同植酸含量对复合膜的结晶结构、微观形貌、透明度、溶胀性和机械强度的影响，进而分析探究植酸对明胶膜的结构调控和性能改善作用。结果表明，与纯明胶膜相比，植酸对明胶有明显的交联改性作用，复合膜具有致密均一的内部结构，植酸通过极性基团的相互作用抑制了明胶的自结晶行为，使复合膜结晶度降低。随着植酸含量的增加，复合膜的可见光透过率下降，溶胀率变化表明植酸与明胶的结构重组能有效阻隔水分子的渗透。复合膜力学强度随着植酸的加入呈上升趋势，当植酸质量分数达10%时，植酸/明胶复合膜拉伸强度约为61.57MPa，较纯明胶的拉伸强度（50MPa）提高了约20%，但对断裂伸长率无明显作用。

关键词: 植酸, 明胶, 复合膜, 透光率, 溶胀率, 力学性能