- 學位論文
聚碳酸酯(PC)分子降解及摻混黏土之性能探討
Study on the Molecular Degradation of Polycarbonate (PC) And the Properties of PC/Clay composites by Blending Process.
摘要
塑膠在初次射出加工成型製程中所產生的物料再碾壓成更小的膠粒後，與新純料混合成再造料稱為二次料。本論文重點在說明塑膠二次料的製程及其對塑料特性的影響，以及成型者在使用塑膠次料時的須知事項。本文所提及的研究主要探討聚碳酸酯樹脂(PC)經由二次射出成型，或以部份二次射出的高分子與部份原粒共混射出的產品，其高分子鏈段受到高熱降解、力降解、氧化降解或氧化交鏈、機械應力減弱了斷鍵的反應活化能等破壞高分子原本性能的因素，使聚碳酸酯樹脂(PC)性能上發生分子量下降、外觀黃化、加工流動性增大、衝擊強度減弱、彎曲強度下降、熱穩定性下降等變化。這些量測數據上的改變對應到產品的實際使用情形則是有易脆、柔韌度不足或不美觀等問題；若是需支撐產品結構的射出件就會因為添加二次料而在使用時容易斷裂，產品的生命週期大幅衰減；若是作為透明光學零組件就會因為添加二次料產生外觀發黃現象，光學性能大幅下降造成產品失效的問題。
並列摘要
The first injection molding of plastic there has surplus plastic material which produced during injection molding process and it will run over to small pieces then blend with new material. After that, the rebuild material is called the second injection molding material. The key point of this dissertation is description the process of second injection molding material corresponding plastic property effect and the second injection molding material have to be noticed when user molded this material. In this study, I investigated the polycarbonate resins (PC) to perform second injection molding or partial polymer, which used second injection molding with partial raw material hybrid as injection molding product. At that time the polymer chain will suffered height temperature, degradation, physical strength degradation, and oxidation degradation, or oxidation crosslink, mechanical stress lead to polymer chain broken activation energy dropped. So as to the polycarbonate resins (PC) molecular weight was dropped, the appearance change to yellow color, more fluid when operation, impact strength dropped, bend strength dropped, thermal stable dropped. These measurements of this product indicate highly brittle, insufficient toughness or poor appearance due to add second material. These products which was used as a supporting structure have brittle property and short lifetime with the second injection molding material. As the transparent optics components, there’s yellow appearance come forming because of second injection molding material and the optics properties dropped and lead to a failed product.