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首页> 外文期刊>Thermochimica Acta: An International Journal Concerned with the Broader Aspects of Thermochemistry and Its Applications to Chemical Problems >SOLUBILITY, CURING AND HEAT RESISTANCE OF SOME ESTER-IMIDE OLIGOMERS AS A FUNCTION OF THE NATURE AND CONTENT OF SOME COMONOMERS
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SOLUBILITY, CURING AND HEAT RESISTANCE OF SOME ESTER-IMIDE OLIGOMERS AS A FUNCTION OF THE NATURE AND CONTENT OF SOME COMONOMERS

机译：某些酯类酰亚胺低聚物的溶解度，固化和耐热性随某些共聚单体的性质和含量的变化

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Substitution of ethyl glycol by neopentylglycol in ester-imide oligomers increases solubility and decreases glass transition temperature, while increase of quantity of dimethylterephthalate has opposite effects. Oligomer containing neopentylglycol and the lower quantity of dimethylterephthalate, which dissolves even in mixtures of methyldipropyleneglycol/xylene or toluene 1/1 by weight to obtain 40% or more concentrated solution, is the most convenient. Heat resistance, mechanical and electrical properties, and dielectric losses are optimum if oligomers are cured by heating for 4 h at 260 degrees C. Curing consists in increase of molecular weight and transformation of oligomers in polymers by the elimination of water and diols. Thermal degradation of polymers involves three stages: elimination ol unreacted comonomers and of a part of bound diols; elimination of the rest of diols, dimethylterephthalate and tris-(2-hydroxvethyl)isocianurate; elimination of structures trimellitic anhydride - diaminodiphenylmethane containing aromatic and imidic rings. Neopentylglycol and large quantities of dimethylterephthalate reduce the heat resistance of polyester-imides. [References: 24]
机译：在酯酰亚胺低聚物中新戊二醇取代乙二醇可增加溶解度并降低玻璃化转变温度，而增加对苯二甲酸二甲酯的用量则有相反的作用。最方便的是含有新戊二醇和较少量的对苯二甲酸二甲酯的低聚物，该低聚物甚至溶解在按重量计的甲基二丙二醇/二甲苯或甲苯的1/1混合物中，得到40％或更高浓度的溶液。如果通过在260摄氏度下加热4小时固化低聚物，则耐热性，机械和电气性能以及介电损耗是最佳的。固化过程包括通过消除水和二醇来增加聚合物的分子量以及低聚物的转变。聚合物的热降解涉及三个阶段：消除未反应的共聚单体和部分结合的二醇;消除其余的二醇，对苯二甲酸二甲酯和三-（2-羟乙基）异氰尿酸酯;消除结构偏苯三酸酐-含芳族和亚胺基环的二氨基二苯甲烷。新戊二醇和大量的对苯二甲酸二甲酯会降低聚酯酰亚胺的耐热性。 [参考：24]

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