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首页> 外文期刊>Journal of Applied Polymer Science >RATE OF IMIDIZATION OF POLYMERIZABLE REACTION MIXTURES - PMR-15
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RATE OF IMIDIZATION OF POLYMERIZABLE REACTION MIXTURES - PMR-15

机译：可聚合反应混合物的虚拟化速率-PMR-15

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Imidization of PMR-15 was investigated using Fourier transform infrared spectroscopy (FTIR) as a function of time and temperature. Imidization was performed at 65 less than or equal to T less than or equal to 300 degrees C for 3 less than or equal to t less than or equal to 150 min. FTLR spectroscopy showed that imidization (measured by the changes in the imide carbonyl absorption at 1778 sm(-1)) increased with temperature and time. Imidization was found to be nearly completed in 2.5 h at 300 degrees C. Imidization of PMR-15 occurred in three stages: (i) the initial imidization region characterized by gradual reaction followed by (ii) a very rapid reaction region that spans about 0.5 h and (iii) a final imidization region characterized by a gradual reaction and spans about 2 h. An Avrami-type kinetic analysis was used to obtain the reaction order of 1.5 and 1.7 and the rate constant for imidization of 1.3 x 10(-3) and 1.5 x 10(-3) min(-3/2) at 135 and 165 degrees C, respectively. Comparison with other kinetic models shows agreement at low conversions (p less than or equal to 15%). At high conversions of p > 20%, a second-order kinetic model seems to fit the data reasonably well in agreement with the observed 3/2 order. (C) 1997 John Wiley & Sons, Inc. [References: 11]
机译：使用傅里叶变换红外光谱（FTIR）研究了PMR-15的亚胺化与时间和温度的关系。在小于或等于T的65℃或小于等于300℃下进行亚胺化3个小于或等于t的时间小于或等于150分钟。 FTLR光谱显示，酰亚胺化（通过1778 sm（-1）处的酰亚胺羰基吸收变化来衡量）随温度和时间的增加而增加。发现亚胺化在300摄氏度下于2.5小时内几乎完成。PMR-15的亚胺化分三个阶段进行：（i）以逐渐反应为特征的初始亚胺化区域，然后是（ii）跨越约0.5的非常快速的反应区域h和（iii）以渐进反应为特征的最终酰亚胺化区域，跨度约2h。使用Avrami型动力学分析获得了1.5和1.7的反应顺序以及在135和165处酰亚胺化的速率常数1.3 x 10（-3）和1.5 x 10（-3）min（-3/2）摄氏度。与其他动力学模型的比较显示出低转化率（p小于或等于15％）时的一致性。在p> 20％的高转化率下，二阶动力学模型似乎可以很好地拟合数据，与观察到的3/2阶一致。 （C）1997 John Wiley＆Sons，Inc. [参考：11]

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