摘要
在超临界CO2介质中由双酚A(BPA)和碳酸二苯酯(DPC)合成了双酚A型聚碳酸酯(PC)。反应生成的苯酚能够溶解扩散到超临界流体中。用红外光谱(FT-IR)、核磁共振谱(1H-NMR)表征了产物的结构。凝胶渗透色谱(GPC)测试表明,合成过程中存在线形缩聚和成环两种不同的反应机理,产物的重均分子量高达117740,分子量分布指数Pd=1.33;差示扫描量热法(DSC)测试表明,超临界CO2能增塑PC致使其玻璃化转变温度(Tg)降低。考察了反应时间、搅拌转速、反应温度等因素对PC分子量的影响。在反应压力为10MPa下较佳反应时间为50h,较佳搅拌转速为800r.min-1,较佳反应温度为120℃。
Polycarbonate （PC） was prepared by transesterification between bisphenol-A （BPA） and diphenyl carbonate （DPC） in supercritical carbon dioxide （ScCO2）. In the process, phenol formed from the reaction was dissolved and diffused into ScCO2 phase. The structure of the synthesized product was characterized by FT-IR and ^1H-NMR. The results of GPC show that there are two different reaction mechanisms, linear condensation and cyclic reaction in the synthesis process, and the molecular weight （Mw） reaches 1.17 × 10^5 and Pd is 1.33. The DSC curves show that supercritical carbon dioxide can plasticize PC so that the Tg of PC decreased. Under the pressure of 10 MPa, the effects of reaction time, rotary speed of the propeller and reaction temperature on PC molecular weight were investigated. The optimal operation conditions are reaction time of 50 h, rotary speed of 800 r · min^-1 , reaction temperature of 120℃, respectively.
出处
《化工学报》
EI
CAS
CSCD
北大核心
2007年第9期2403-2407,共5页
CIESC Journal
基金
国家自然科学基金项目(20076036)
湖北省新型反应器与绿色化学工艺重点实验室开放基金~~
关键词
超临界
CO2
聚碳酸酯
supercritical
carbon dioxide
polycarbonate
