• 关键词：聚碳酸酯  甲醇  临界区域  降解  机理

• 基金项目：国家自然科学基金(20076013)项目

• 陈磊
• 华东理工大学化学工艺所, 上海 200237

• 吴勇强
• 华东理工大学化学工艺所, 上海 200237

• 倪燕慧
• 华东理工大学化学工艺所, 上海 200237

• 黄科
• 华东理工大学化学工艺所, 上海 200237

• 朱子彬
• 华东理工大学化学工艺所, 上海 200237

• 摘要：在间歇高压反应器中研究了聚碳酸酯在甲醇临界区域的降解行为.降解无需借助催化剂, 降解温度220-260℃, 压力5.20-8.67MPa, 时间5-4.5min, 通过GCMS与GCf_iD对液相产物进行了定性和定量分析, 聚碳酸酯醇解主要产物为碳酸二甲酯(DMC)和双酚A(BPA).降解温度和时间为240℃和30min时, DMC和BPA的产率分别91.75%和90.03%.通过凝胶渗透色谱(GPC)对240℃醇解反应的固相聚合物进行了分析.降解初期, 聚合物大分子发生断裂, PC的数均分子量(Mn)迅速下降, 仅有少量DMC和BPA生成;降解的中间阶段, 低聚物在降解产物中的比例快速增加, 同时DMC与BPA相应增多, 最终PC被完全分解.

• Abstract：Depolymerization of polycarbonate in critical region of methanol was studied in absence of catalysts and in a batch-type autoclave at reaction temperature of 220-260℃ and with reaction time of 5-45min. The main liquid products were demethyl carbonat (DMC) and bisphenol-A(BPA), which were identified and quantified by GC/MS and GC/FID. In critical region of methanol at 240℃ for reaction time of 30min, the yield of DMC and BPA reached 91.75% and 90.03%, respectively. Gel Permeation Chromatography was used to measure the number-average molecular weight ((Mn)) of solid products. Based on the experiments, mechanism of methanolysis was proposed in this paper.

• Key words：polycarbonate  methanol  critical region  depolymerization  mechanism

• 
  摘要点击次数： 1662 全文下载次数： 2731