在样品具有较高的粘度的情况下，不可能通过直接测量得到高聚物的混合热（
相互作用热）。在此提供一种间接方法-溶解法 测得聚合物的混合热，利用盖斯定律测定同一溶剂内不同组分的热量，由此得到混合热。
方案详情
AN089PolumersHeat of mixing of polymer alloysby a heat of solution methodExcellence in thermal analysis and calorimetry Reference： P.N. Aukett and C.S Brown， J. Of Thermal Analysis， Vol 33， 1079-1084， (1988).BP Research Center，Sunbury-On-Thames，Middlesex， U.K. Introduction： direct measurement of the heat of mixing (interaction) ofpolymers is not feasibledue to their high viscosity. The indirect approach described here is a heat of solution method， inwhich a Hess’s Law cycle is used to determine the heat of mixing from the individual heats ofsolution of the alloy and its constituent polymers in a common solvent. The main limitation of thisapproach lies in obtaining adequate precision on the experimentally determined heats of solution，as these are large compared to the calculated heat of mixing. With this method the heat of mixing of a 75/25 (% by wt) poly(dimethyl) phenylene oxide/polystyrene alloy has been determined by SETARAM C80 microcalorimeter as 4.9+0.2 J.g-1. The precision of the method shows an improvement compared with published data. Heat of solution method In the heat of solution method a Hess’s Law cycle is used to determine AHm from the heats ofsolution (AHs) of the alloy and its constituents in a common solvent [6， 7]. Figure 1 illustrates thecycle used to determine AHm. AH、 Fig.1 Hess’s law scheme used to calculate AHm from the heats of alloy and its constituenthomopolymers (7) Heat of solution in 1，2-dichlorobenzene (J.g1) Material Mean Range Polystyrene 25.9 ±0.15 0.05 Poly(dimethylphenylene oxide) 55.2 ±0.3 0.1 PPO/PS 75%/25% 40.1 ±0.45 0.2 For more details ask forpublications B0623， B683， B684，B893 Table 1 Heats of solution of homopolymers and alloy 20℃/300℃ www.setaram.com - sales @setaram.com
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凯璞科技（上海）有限公司为您提供《测定聚合物合金的混合热》，该方案主要用于合金中--检测，参考标准--，《测定聚合物合金的混合热》用到的仪器有C80 微量热仪
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