活性纳米CaCO3/POE复配体系增强增韧渔用聚乙烯纤维机理研究

With the development of fishery science and technology, the existing fishery fibers have been difficult to meet the needs of the special fishery operation and energy conservation, low-carbon fisheries. In this project, activated nano-CaCO3/POE composite system will be used for toughening and strengthening the fishery high density polyethylene (PE) and the fishery PE fiber would be fabricated by melt spinning-drawing one step method. The relationship between the evolutions of aggregation structure of the fishery PE fiber, including the crystal structure, the orientation structure and so on, and its combination mechanical properties will be systematic studied. Furthermore, the toughening and strengthening mechanism will be revealed. Therefore, the component and distribution of the nano-CaCO3/POE composite system in the PE fiber will be investigated. In addition, effect of the melt spinning-drawing processing parameters on the aggregation structure and performance of the resulting PE fiber will be studied to reveal the modification mechanism. Based on the modulation the aggregation structure and performance of fishery PE fiber, it will provide the theoretical guidance for development and design the fishery high performance fiber material.

随着渔业科技的发展，现有普通渔用纤维已难以满足我国渔业作业特殊化以及节能低碳的需要。本项目拟采用活性nano-CaCO3/POE弹性体复配体系对渔用聚乙烯进行增强增韧改性，采用熔融纺丝-多级牵伸一步法成形制备渔用高强高韧聚乙烯纤维。研究渔用聚乙烯纤维中结晶结构、取向结构等凝聚态结构的演变规律及与其综合力学性能之间的关系，深入研究活性nano-CaCO3/POE弹性体复配体系对渔用聚乙烯纤维的增强增韧机理。为此本项目将系统研究活性nano-CaCO3/POE复配体系的配比及其在聚乙烯纤维中的分散及熔融纺丝-多级牵伸工艺对渔用聚乙烯纤维结构与性能的影响。基于渔用聚乙烯纤维凝聚态结构与其综合力学性能的调控及相关规律研究，将为渔用合成纤维带来革新性的变化，为渔用高性能纤维材料的开发和设计提供理论指导。

随着渔业科技的发展，现有普通渔用纤维已难以满足我国渔业作业特殊化以及节能低碳的需要。本项目以纳米碳酸钙/乙烯辛烯共聚物（nano-CaCO3/POE）复配体系为改性剂，采用两种共混工艺，调节nano-CaCO3/POE复配体系在渔用高密度聚乙烯（HDPE）基体中的配比及含量，控制其在聚乙烯基体中的分散，制备了核壳结构nano-CaCO3/POE复配体系改性聚乙烯三元复合材料和改性聚乙烯单丝。研究了共混工艺、复配体系配比及其含量对nano-CaCO3/POE/HDPE复合材料和单丝的微观形态结构和宏观力学性能的影响。结果表明，当复配体系中 nano-CaCO3和POE质量比为1:4时，两步法共混工艺可使nano-CaCO3与POE在聚乙烯基体中形成nano-CaCO3为核、POE为壳的核壳结构，且该核壳结构由POE包裹2-3颗nano-CaCO3粒子组成，尺寸为100-200nm，均匀分散于聚乙烯基体中。此外，当核壳结构nano-CaCO3/POE复配体系的含量为5%时，所制备的nano-CaCO3/POE/HDPE三元复合材料和改性聚乙烯单丝的综合力学性能最优。当一级拉伸倍数为8.17倍，总拉伸倍数为9.52倍时，改性聚乙烯单丝的断裂强度和结节强度分别为6.65 cN/dtex和4.63 cN/dtex。比我国现行水产行业标准《SC/T 5005-2014渔用聚乙烯单丝》中规定的优等品指标高出27.88%和28.61%。此外，当总拉伸倍数进一步增高到10.71倍时，改性聚乙烯单丝的断裂强度进一步增加到7.50 cN/dtex，但是其结节强度下降至3.85 cN/dtex。根据渔用单丝的使用特性，结节强度高的聚乙烯单丝可用于渔网，而断裂强度高的聚乙烯单丝可用于制作绳索。