聚-3-羥基丁酸酯改質之結晶及劣化性質研究

Degradation and Crystallization of Poly-3-hydroxybutyrate Modified by Carboxyl Terminated Butadiene Acrylonitrile and Polyvinylpyrrolidone

高琮凱(Tsung-Kai Gau)

指導教授 ： 洪信國

元智大學/工程學院/化學工程與材料科學學系/碩士(2008年)

https://doi.org/10.6838/YZU.2008.00312

摘要

本研究探討添加羧基聚丁二烯丙烯腈(CTBN)及聚乙烯基吡咯烷酮( PVP )改質聚-3-羥基丁酸酯(PHB)之結晶及熱劣化性質。由DSC數據證實，添加CTBN或PVP都會提高PHB的結晶溫度、結晶速率和熔融溫度。添加CTBN、PVP在增加立體障礙，減緩其高溫下的分子量裂解。而以添加1wt. % PVP有最高的結晶溫度和結晶速率。TGA分析，曝露儲存的PHB熱穩定性明顯變差，而熱裂解動力的活化能幾乎沒有改變、熱裂解反應都只有單一裂解步驟，添加CTBN或PVP都提高其熱穩定性、熱裂解反應的活化能。70度C結晶7天，對於密封儲存PHB機械強度與延伸率無顯著影響。

關鍵字

聚-3-羥基丁酸酯 ； 羧基聚丁二烯丙烯腈聚乙烯基吡咯烷酮 ； 改質劑 ； 結晶 ； 熱劣化

並列摘要

The crystallization and thermal degradation properties of poly-3-hydroxybutyrate (PHB) modified with carboxyl terminated butadiene acrylonitrile (CTBN) and polyvinylpyrrolidone (PVP) are studied by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). The results of DSC indicate that the addition of CTBN or PVP can increase the crystallization temperature, crystallization rate, and melting temperature of PHB due to the increase of steric hindrance which improves the thermal stability of PHB during high temperature exposure. The highest crystallization rate is obtained from the PHB with one weight percent PVP. From TGA analyses, it is obtained that the thermal degradation is a one-step reaction, which is not affected by the addition of CTBN or PVP, while the activation energy increases in the presence of CTBN and PVP. All PHB with CTBN and PVP have better thermal stability than unmodified PHB.

並列關鍵字

PHB ； CTBN ； PVP ； modifier ； crystallization ； thermal degradation

參考文獻

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