<論文>カプリル化木材とポリエチレン,ナイロンおよびポリエステルとのブレンド物の混和性

Abstract

カプリル化木材の力学緩和機構を明らかにし,さらに,それと2・3の合成高分子とのブレンド物の混和性の程度を検討した。カプリル化木材フィルムに関する動的粘弾性測定の結果,3種の緩和過程を見い出し,それらを高温側からαcw,βcwおよびγcwと名付けた。αcwはカプリル化した木材主成分分子鎖のミクロブラウン運動に,βcwぱ側鎖カプリル基の運動に,γcwぱ直鎖メチレソ単位を少くとも3個程度含む運動に,それぞれ基づくと考えられた。また,応力一伸び測定の結果,カプリル化木材フィルムの破断時伸びは90%に達した。カプリル化木材とポリエチレソ,ナイロソ,あるいはポリエステルとのブレンド物の混和性を検討した結果,いずれも二相混合系を形成することが明らかとなった。その際,用いた合成高分子の種類によって混合の程度に差が認められ,差の判定には破断時伸びが最も適当な指標であった。この結果,カプリル化木材との混合状態が最もすぐれているものはポリエステルで,ポリエチレソが最も悪いことが明らかとなった。

Mechanical relaxation processes occurring in caprated wood were assigned and compatibility of caprated wood with a few synthetic polymers was investigated. Three types of relaxation process were observed in loss tangent versus temperature curve for caprated wood film. These processes were labelled αcw, βcw and γcw in order of decreasing temperature at which they occurred. These αcw to γcw processes were, respectively, attributed to; micro-Brownian motion of main chain (αcw), motion of side chain (βcw) and motion initiated by three or more methylene groups (γcw). The caprated wood film underwent a high degree of elongation of 90% prior to failure in tensile test at room temperature. Blends of caprated wood with polyethylene, nylon or polyester showed two-phase systems. In such a case, however, some differences in compatibility among these blends were recognized. The ultimate elongation of the film was the best criterion for detecting the differences in compatibility. Blends of caprated wood with polyester were the best of the three.