Mao Long, Xie Jianda, Wu Huiqing, Liu Yuejun
Fujian Provincial Key Laboratory of Functional Materials and Applications, Xiamen University of Technology, Xiamen 361024, China.
Key Laboratory of Advanced Packaging Materials and Technology of Hunan Province, Hunan University of Technology, Zhuzhou 412007, China.
Polymers (Basel). 2020 Sep 15;12(9):2093. doi: 10.3390/polym12092093.
Inspired by complexation and mussel adhesion of catechol groups in tannic acid (TA), organophilic layered double hydroxides (LDHs@TA-Ti) were synthesized by forming a one-pot assembled TA-titanium (Ti) dual network coating on the surface of layered clay for the first time. LDHs@TA-Ti/poly(vinyl alcohol) (PVA) nanocomposites were prepared by the solution casting method. The results show that TA-Ti(IV) and TiO coordination compounds are simultaneously formed due to hydrolysis of titanium tetrachloride and complexation of TA in aqueous solution. Upon TA-Ti coatings onto the surface of LDHs, the antibacterial rate of LDHs@TA-Ti is up to 99.98%. Corresponding LDHs@TA-Ti/PVA nanocomposites also show outstanding antibacterial properties. Compared with pure PVA, LDHs@TA-Ti/PVA nanocomposites show a 40.9% increase in tensile strength, a 17.5% increase in elongation at break, a 35.9% decrease in oxygen permeability and a 26.0% decrease in water vapor permeability when adding 1 wt % LDHs@TA-Ti. UV transmittance (at 300 nm) of LDHs@TA-Ti/PVA nanocomposites decrease by 99.4% when the content of LDHs@TA-Ti reaches 3 wt %. These results indicate that PVA matrix incorporated with LDHs@TA-Ti could be used as a potential active packaging material to extend the shelf life of food products.
受单宁酸（TA）中邻苯二酚基团的络合作用和贻贝粘附作用的启发，首次通过在层状粘土表面形成一锅组装的TA-钛（Ti）双网络涂层，合成了亲有机层状双氢氧化物（LDHs@TA-Ti）。采用溶液浇铸法制备了LDHs@TA-Ti/聚乙烯醇（PVA）纳米复合材料。结果表明，由于四氯化钛的水解和TA在水溶液中的络合作用，同时形成了TA-Ti（IV）和TiO配位化合物。在LDHs表面涂覆TA-Ti涂层后，LDHs@TA-Ti的抗菌率高达99.98%。相应的LDHs@TA-Ti/PVA纳米复合材料也表现出优异的抗菌性能。与纯PVA相比，添加1 wt%的LDHs@TA-Ti时，LDHs@TA-Ti/PVA纳米复合材料的拉伸强度提高了40.9%，断裂伸长率提高了17.5%，透氧率降低了35.9%，水蒸气透过率降低了26.0%。当LDHs@TA-Ti的含量达到3 wt%时，LDHs@TA-Ti/PVA纳米复合材料的紫外线透过率（300 nm处）降低了99.4%。这些结果表明，掺入LDHs@TA-Ti的PVA基体可作为一种潜在的活性包装材料，以延长食品的保质期。
