氫鍵作用力對高分子摻合系統相容性的影響

Abstract

本論文探討酚醛樹脂（Phenolic）與聚乙酸乙烯酯（PVAc（poly vinyl acetate））混摻後的氫鍵作用力及相容性。在酚醛樹脂/聚乙酸乙烯酯摻合系統中，酚醛樹脂上的羥基與聚乙酸乙酯上的羰基會產生氫鍵而利於相容。微分掃描熱卡計（DSC）的結果顯示，酚醛樹脂/聚乙酸乙烯酯摻合的所有組成均只有一個玻璃轉移溫度（Tg），顯示此摻合系統為相容。此外，分別以紅外線光譜儀（FT-IR）及固態核磁共振儀（NMR）定量及定性的探討羥基與羰基之間的氫鍵作用力，結果為一致，均顯示隨著酚醛樹脂的加入，羥基與羰基之間產生的氫鍵明顯增加，表示酚醛樹脂上的羥基與聚乙酸乙酯上的羰基可產生強的分子間氫鍵作用力（inter-association）。此外，由質子自旋晶格遲緩時間（T1ρH）的實驗結果中，顯示Phenolic/PVAc摻合系統在2-3nm 以下為相容。更進一步藉由Painter-Coleman association model，可計算出分子間結合作用力平衡常數（inter-association equilibrium constant）及相對焓。

The miscibility and hydrogen bonding of phenolic resin/poly(vinyl acetate) (PVAc) blends were studied. The miscibility of phenolic resin and poly(vinyl acetate) (PVAc) blends was investigated by differential scanning calorimeter (DSC), Fourier transform infrared spectroscopy (FT-IR) and solid state 13C nuclear magnetic resonance (NMR). This blend displays single glass transition temperature (Tg) over entire compositions indicating that this blend system is miscible in the amorphous phase due to the formation of hydrogen bonding between hydroxyl groups of phenolic resin and carbonyl groups of PVAc. Quantitative measurements on fraction of hydrogen-bonded carbonyl group using both 13C solid-state NMR and FT-IR analyses result in good agreement between these two spectroscopic techniques. According to the proton spin-lattice relaxation time in the rotating frame (T1ρH), the phenolic/PVAc blend is intimately mixed on a scale less than 2-3 nm. Furthermore, the inter-association equilibrium constant and its related enthalpy of phenolic/PVAc blends were determined as a function of temperatures by infrared spectra based on the Painter-Coleman association model.