Correlation analysis between biodegradable nature and microstructure of functional hybrid materials using biomass

首先，在草酸水溶液存在下，建立了一种基于反应裂解-气相色谱法直接快速测定甲壳素乙酰化度的新方法。乙酰化度是根据特征热解产物的峰强度精确测定的。实验结果与~ 1H-NMR及其它方法的测定结果一致。此外，所提出的技术适用于整个乙酰化范围内的任何种类的甲壳素样品，包括不溶性甲壳素和具有更高结晶度的完全乙酰化的人工甲壳素，^1H NMR不适用于此。壳聚糖衍生物/聚聚氯乙烯（PVC）的杂化物的特点主要是在他们的可溶解性和网站的分子间相互作用的程序升温热解（TPPy）。质谱和TPPy-原子发射检测。通常观察到与相应共混聚合物的降解相对应的混合物在三个阶段中明显地逐步降解。然而，每个降解峰温度被证明与混合物的可降解性相关。此外，在PVC在低于300 ℃的相对较低温度下的脱氯化氢阶段期间，由甲壳质衍生物和PVC形成的许多特征产物的形成引发甲壳质衍生物的降解，甲壳质衍生物应稳定至约100 ℃。350摄氏度

Firstly, anew method to determine directly and rapidly the degree of acetylation of chitin was developed based on reactive pyrolysis-gas chromatography in the presence of an oxialic acid aqueous solution. The degree of acetylation was precisely determined on the basis of peak intensities of the characteristic pyrolysis products. The observed values were in good agreement with those obtained by ^1H-NMR and the other methods. Moreover, the proposed technique was applicable to any kinds of chitin samples over the whole range of acetylation including insoluble chitin and perfectly acetylated artificial chitin having higher crystallinity to which ^1H NMR had been inapplicable.Next, chtin derivative/poly(vinyl chloride) (PVC) hybrids were characterized mainly in terms of their miscibility and sites of the intermolecular interactions by temperature programmed pyrolysis (TPPy)-mass spectrometry and TPPy-atomic emission detection. Stepwise degradation apparently in three stages was commonly observed for the hybrids corresponding to the degradation of the respective blending polymers. However, each degradation peak temperature proved to change correlating to the miscibility of the hybrids. Moreover, during the dehydrochlorination stage for PVC at relatively lower temperatures below 300ﾟC, the evolution of many characteristic products formed from the chitin derivative and PVC were triggering the degradation of the chitin derivatives which should be stable up to ca. 350ﾟC.