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首页> 外文期刊>Journal of Applied Polymer Science >COPOLYESTERS OF POLY(ETHYLENE TEREPHTHALATE), HYDROQUINONE DIACETATE, AND TEREPHTHALIC ACID - A SIMPLE RATE MODEL FOR CATALYZED SYNTHESIS IN MELT
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COPOLYESTERS OF POLY(ETHYLENE TEREPHTHALATE), HYDROQUINONE DIACETATE, AND TEREPHTHALIC ACID - A SIMPLE RATE MODEL FOR CATALYZED SYNTHESIS IN MELT

机译：聚对苯二甲酸乙二酯，对苯二酸二苯甲酸酯和对苯二甲酸的共聚酯-熔融过程中催化合成的简单速率模型

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Transesterification reactions between poly(ethylene terephthalate) (PET), hydroquinone diacetate (HQDA), and terephthalic acid (TA), were conducted via the melt polymerization route with the objective of analyzing the copolyesterification kinetics of a phase separated system. At first homopolymerization of HQDA and Th were conducted at 50 mol % composition of each monomer. Then the polymerization kinetics of four compositions [PET 30/70 (HQDA + TA), PET 40/60 (HQDA + TA), PET 50/50 (HQDA + TA), PET 60/40 (HQDA + TA) with 30 : 35 : 35, 40 : 30 : 30, 50 : 25 : 25, and 60 : 20 : 20 mol % PET, HQDA, and TA] were investigated. The following assumptions were made to make kinetic analysis tractable. HQDA and TA combine to form acetic acid and higher oligomers. The oligomer subsequently adds on to the FET chain to give a copolymer of PET/HQDA/TA, the product of interest. The reaction between PET, HQDA, and TA proceeds in a heterogeneous two-phase system consisting of PET-rich and PET-poor regions. The reaction sequence is HQDA and TA react to form a dimer and subsequently the dimer is added onto the PET chain. This reaction sequence is assumed to be valid for the PET-rich and PET-poor phases. Both these reactions were assumed to be second order with respect to the reactants. Reactions wherein the dimer reacts with HQDA or TA to form acetic acid exist, but the probabilities of these processes are small with respect to the main reaction postulated above, thus maintaining the overall mass balance. Moles of acetic acid found experimentally were computed using a standard procedure. The rate constant k under the conditions of phase separation was determined. The rate constant in the presence of PET was higher than that observed in the HQDA and TA reaction. An Arrhenius plot revealed that the catalyst plays a marginal role. Microscopic analysis revealed that the HQDA and TA polymer were nonmelting while copolyesters FET 30/70 (HQDA + TA) to PET 60/40 (HQDA+ TA) melted and were liquid crystalline. (C) 1996 John Wiley & Sons, Inc. [References: 28]
机译：聚对苯二甲酸乙二醇酯（PET），氢醌二乙酸酯（HQDA）和对苯二甲酸（TA）之间的酯交换反应是通过熔融聚合路线进行的，目的是分析相分离体系的共聚酯动力学。首先，以每种单体的50摩尔％组成进行HQDA和Th的均聚。然后，四种组成的聚合动力学[PET 30/70（HQDA + TA），PET 40/60（HQDA + TA），PET 50/50（HQDA + TA），PET 60/40（HQDA + TA）与30：研究了35∶35、40∶30∶30、50∶25∶25和60∶20∶20mol％的PET，HQDA和TA]。为了使动力学分析易于处理，做出了以下假设。 HQDA和TA结合形成乙酸和高级低聚物。随后将低聚物加到FET链上，得到目标产物PET / HQDA / TA的共聚物。 PET，HQDA和TA之间的反应在异相两相系统中进行，该系统由富含PET的区域和缺乏PET的区域组成。反应顺序为HQDA，TA反应形成二聚体，然后将二聚体添加到PET链上。假定该反应顺序对于富PET相和穷PET相均有效。假定这两个反应相对于反应物都是二阶的。存在二聚体与HQDA或TA反应形成乙酸的反应，但相对于上述假定的主要反应，这些过程的可能性较小，因此可保持总体质量平衡。使用标准程序计算实验发现的乙酸摩尔数。确定在相分离条件下的速率常数k。在PET存在下的速率常数高于在HQDA和TA反应中观察到的速率常数。阿累尼乌斯图显示该催化剂起着边际作用。显微镜分析显示，HQDA和TA聚合物未熔融，而FET 30/70（HQDA + TA）到PET 60/40（HQDA + TA）的共聚酯熔融并为液晶。 （C）1996 John Wiley＆Sons，Inc. [参考：28]

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