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

首先，建立了在草酸水溶液存在下，基于反应热解-气相色谱法直接快速测定几丁质乙酰化程度的新方法。根据特征热解产物的峰强度精确测定了乙酰化程度。观测值与核磁共振及其他方法的结果吻合较好。此外，所提出的技术适用于任何种类的几丁质样品在整个乙酰化范围，包括不溶性几丁质和完全乙酰化人工几丁质具有较高的结晶度，^1H NMR已不适用。接下来，通过程序升温热解(TPPy)-质谱法和TPPy-原子发射检测，对甲壳素衍生物/聚氯乙烯（PVC）杂化物的混相性和分子间相互作用位点进行了表征。相对应于共混聚合物的降解，共混物的降解通常分为三个阶段。然而，各降解峰温度的变化与杂种的混相性有关。此外，在相对较低的温度下，PVC的脱氢氯化过程中，由几丁质衍生物和PVC形成的许多特征产物的演变引发了几丁质衍生物的降解，这些产物在350℃左右时应该是稳定的。

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.