Abstract

The structure of a nanofiller in a polymer matrix determines the properties of nanocomposites and a change in the type of structure from local to spatial; for example, formation of the percolation framework of particles (particle aggregates) of a nanofiller leads to a sharp deterioration in the properties of nanocomposites. Using the example of particulate-filled polymer/nanodiamond nanocomposites, it is shown that the transition from the standard mixing mode of a nanofiller with a polymer matrix melt in an extruder to mixing in the flow “breakdown” mode leads to a significant increase in the properties of nanocomposites. It is established that this effect is caused by a change in the type of structure of the nanofiller in the polymer matrix from a continuous spatial one (chain of nanofiller particles) to a local one (formation of individual clusters of nanoparticles). Within the framework of the fractal analysis, it is demonstrated that, when the type of structure changes from one-dimensional to two-dimensional, its fractal dimension changes from 1.18 to 1.75. The quantitative estimates of the degree of reinforcement of nanocomposites carried out within the percolation model with the established increase in the fractal dimension of the structure of the nanofiller are fully confirmed by experimental data. It is also shown that the elastic modulus of the nanofiller depends on the stiffness of the polymer matrix. The experimentally observed effect of dispersion of a nanofiller when mixing components in the “breakdown” mode is described in terms of the model of irreversible aggregation.

中文翻译：

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聚合物基体中纳米填料的局部和空间结构及其对纳米复合材料性能的影响

摘要

聚合物基质中纳米填料的结构决定了纳米复合材料的性能以及结构类型从局部到空间的变化。例如，纳米填料的颗粒（颗粒聚集体）的渗透框架的形成导致纳米复合材料的性能急剧下降。以颗粒填充的聚合物/纳米金刚石纳米复合材料为例，研究表明，从挤出机中的纳米填料与聚合物基体熔体的标准混合模式过渡到流动“击穿”模式的混合，会导致颗粒的显着增加。复合材料的性能。可以确定，这种影响是由于聚合物基质中纳米填料的结构类型从连续的空间填料（纳米填料颗粒链）变为局部填料（纳米颗粒的单个簇的形成）而引起的。在分形分析的框架内，证明了，当结构的类型从一维变为二维时，其分形维数从1.18变为1.75。实验数据充分证实了在渗滤模型内进行的纳米复合材料增强程度的定量估计，并确定了纳米填料结构的分形维数增加。还显示出纳米填料的弹性模量取决于聚合物基质的刚度。