功率补偿式DSC曲线的理论分析  

Theoretical analysis on power compensation DSC curves

作　　者：任婉婷[1] 王颖[1] 

机构地区：[1]中国纺织科学研究院生物源纤维制造技术国家重点实验室,北京100025

出　　处：《纺织学报》2010年第1期11-18,共8页Journal of Textile Research

基　　金：教育部留学归国人员科研启动基金(B-95)

摘　　要：根据能量守恒和热传递定律,推导出功率补偿式DSC曲线的理论方程。以纯物质铟的DSC熔融曲线为例,说明其升温扫描过程可分为熔融前、熔融和熔融后3个阶段以及与DSC理论方程的对应关系。DSC曲线分析结果表明:熔点温度对应熔融起始温度;熔融后阶段的曲线以指数形式衰减,热时间常数值越大,熔融后曲线的拖尾时间越长;熔融焓对应于DSC曲线的基线以上和熔融开始至熔融结束曲线以下所包络的面积。论证了测定热阻的理论依据及热阻对DSC曲线的影响。以多组分样品体系的模拟DSC曲线为例,说明聚合物熔融DSC曲线的特征来源。A theoretical formula of power compensation DSC curve was derived from the law of energy conservation and heat transfer. The DSC melting curve of pure indium was studied as an example. It was illustrated that the heating trace of pure indium consists of three parts, which include ＂before melting＂, ＂melting＂ and ＂after melting＂ process corresponding to the three components of DSC theoretical formula, respectively. DSC curve analysis disclosed that melting temperature corresponds to the onset temperature of ＂melting＂ curve. ＂After melting＂ curve decays exponentially. The larger the value of thermal time constant is, the longer the time of ＂after melting＂ curve experiences. Melting enthalpy equals to the area above base line and beneath ＂melting＂ and ＂ after melting＂ curve. The theoretical basis for thermal resistance （R） measurement and the effect of R on the DSC curve shape were illustrated. A simulated DSC curve of a multi-component system was produced to explain the origin of the characteristics of DSC melting curve of polymers.

关 键 词：差示扫描量热(DSC) 功率补偿式DSC 热阻 热时间常数 

分 类 号：TQ317[化学工程—高聚物工业]