將微米和奈米尺度的顆粒添加到高分子基質中通常會增加複合材料的黏度。不過，研究發現添加奈米顆粒於基質有可能反而造成複合物的黏度下降。對於造成黏度降低的機制目前尚未完全理解，為了解決這個問題，我們的研究旨在探究複合物黏度的降低可能來自於空間排列的變化。同時，我們還探索了複合物的宏觀性質變化，如熱性質和流變性質等，這些都是為了釐清黏度降低的機制。我們合成了不同尺寸的聚苯乙烯奈米顆粒，並將其分散在分子量低於或高於纏結臨界值的聚苯乙烯基質中。我們發現黏度下降的行為僅發生於纏結基質系統，並觀察到黏度降低約90 %。透過小角度和廣角度X射線散射實驗，我們認為奈米粒子的添加可能會影響分子鏈的結構排列。對於纏結分子鏈，粒子可能減弱糾纏的密度而增強鏈的流動性。透過結合微觀的分子排列行為與宏觀的黏度特性表現，我們希望建立這些性質之間的相關性，從而解釋黏度降低的機制。;The addition of micro- and nanoscopic particles to a polymer matrix typically increases the viscosity of the composite material. However, the studies have found that adding nanoparticles to the matrix may result in the viscosity reduction of the composite. The mechanism responsible for the viscosity reduction is not fully understood. To address this issue, our study aims to investigate how changes in spatial arrangement may contribute to the viscosity reduction. Also, we explore the macroscopic properties change of the composite, such as thermal and rheological properties, all in an effort to understand the mechanism behind the viscosity reduction. We synthesized the polystyrene nanoparticles with different sizes and dispersed them in the polystyrene matrix with the molecular weight below or above the entanglement threshold. We found that the viscosity reduction behavior only occurred in the entangled matrix system, and observed a viscosity decrease of approximately 90 %. Through the small-angle and wide-angle X-ray scattering experiments, we thought that the addition of nanoparticles may affect the structural arrangement of molecular chains. For the entangled molecular chains, the particles may weaken the density of entanglement and enhance the mobility of the chains. By combining the microscopic molecular arrangement behavior with the macroscopic viscosity characteristics, we hope to establish the correlation between these properties and thereby explain the mechanism of the viscosity reduction.
