含隔离结构的阻隔高分子片材研究

Compared with traditional packaging materials, polymer materials play a critical role in packaging application due to their features of lightweight, inexpensive and easily processing. However, poor gas barrier property of single polymer sheet can hardly meet the demand of various commodities. Therefore, the development of new theory and technology for preparing high barrier polymer packaging materials has been a central issue in packaging and plastic industry. In the current study, graphene oxide nanosheets (GONSs) will be taken as highly effective enhancers of barrier property. GONS/polystyrene (PS) nanocomposite sheet with a segregated structure will be fabricated. In this nanocomposite, GONSs in PS matrix compose the network of "nano-barrier wall", which can endow GONS/PS nanocomposite sheet with high barrier property. The relationship between external processing field, GONS microscopic morphology and barrier property of nanocomposite sheet will be established via systematacially studying on the relationship between coating rate of PS microspheres and grafting rate of GONSs, as well as controlling the GONS/PS segregated structure under the external processing fields. In the meantime,the mechanism of improving the barrier property of nanocomposite sheet will be revealed, which can not only provide theoretical guiding for fabricating high barrier polymer packaging materials, but also expand the application of polymer sheets in the high barrier packaging field.

与传统包装材料相比，聚合物材料以其重量轻、成本低、易加工等特性，在包装领域有着广泛的应用。但单一聚合物材料的气体阻隔性能较差，难以满足商品对包装材料阻隔性能的要求。因此，研究聚合物材料阻隔新原理新技术，开发具有高阻隔性能的聚合物产品成为目前包装产业和塑料工业的"热点"。本项目拟采用氧化石墨烯纳米片（GONSs）作为改善阻隔性能的高效纳米填料，构建GONSs与聚苯乙烯（PS）微球的隔离结构，从而获得GONSs在PS基体中的"纳米阻隔墙网络"，制备具有隔离结构的高阻隔纳米复合片材。通过系统研究PS微球表面的包覆率与GONSs接枝率的关系，加工外场下GONSs/PS隔离结构的调控，建立加工外场、GONSs微观形态和复合片材阻隔性能之间的联系,揭示隔离结构提高复合片材阻隔性能的机理，为开发高阻隔聚合物包装片材提供了理论指导，促进聚合物片材在高阻隔包装领域的应用。

与传统包装材料相比，聚合物材料以其质轻、成本低、易加工等特性，被广泛应用于食品、药品、电子产品的包装。但单一聚合物材料的气体阻隔性能较差，难以满足商品的使用需求。本项目利用层状纳米填料复合技术，以氧化石墨烯（GONSs）为阻隔增强填料，从GONSs的分散形态、复合材料的界面结构、聚合物基体的晶体结构角度，系统阐明了复合材料的气体阻隔增强机理；基于此，从聚合物成型加工手段入手，调控GONSs的分散形态，构筑含隔离结构的三维网络结构，形成“气体阻隔墙”，并结合化学接枝改性和双逾渗思路，优化隔离结构界面形态，制备了具有隔离结构的高阻隔聚合物复合材料，为开发高阻隔聚合物包装材料提供了新思路。此外，根据隔离结构的体积排斥特色，制备了具备特定网络结构的聚合物导电复合材料，获得了高电导率和电磁屏蔽性能，对隔离结构的功能性开发具有重要的指导意义。