針状ケイ酸カルシウム水和物で強化されたナイロン6複合材料の構造キャラクタリゼーション
Structural Characterization of Nylon 6 Composites Reinforced with Microfibrous Calcium Silicate Hydrate
田中秀穂・渡辺邦夫
Tanaka, Hideho / Watanabe, Kunio
The structural features of nylon 6 composites reinforced with xonotlite, 6CaO･6SiO2･ H2O, a microfibrous calcium silicate hydrate, were investigated. The composites were structurally characterized with particular focus on the interface, aspect ratio of the xonotlite and crystalline structure of the matrix resin. Dynamic viscoelasticity measurements of the composites suggest that the nylon 6 molecules may be partly adsorbed on the xonolite surface. This was verified by surface analysis of the xonotlite using scanning probe microscopy and electron spectroscopy for chemical analysis (ESCA). Measurements on dimensional change of the xonotlite during melt blending with the nylon 6 reveal that it not only shortens but also thins. This allows the xonotlite to almost maintain initial aspect ratio even in the composite. This phenomenon can be interpreted in terms of what happens to the xonotlite during compounding, splitting of the primary flocs into many constituent microfibers and their breakage due to shearing motion. Differential scanning calorimetry (DSC) studies on non-isothermal crystallization behavior of the composites show that the xonotlite tends to accelerate the nylon 6 to crystallize based on its nucleating effect, resulting in enhanced crystallinity. The structural features characteristic to this composite, good chemical affinity between the nylon 6 and xonotlite, high aspect ratio of the xonotlite in the composite and the enhanced crystallinity of the nylon 6 matrix are the key factors that play a significant role in its mechanical properties.
Key words: Nylon 6 matrix composite / Xonotlite / Microfibrous / Structural characterization