EFFECT OF TEMPERATURE VARIATIONS ON MOLECULAR-WEIGHT DISTRIBUTIONS - BATCH, CHAIN ADDITION POLYMERIZATIONS
EFFECT OF TEMPERATURE VARIATIONS ON MOLECULAR-WEIGHT DISTRIBUTIONS - BATCH, CHAIN ADDITION POLYMERIZATIONS
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DOI：
10.1016/0009-2509(73)85104-8
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发表时间：
1973-01-01
影响因子：
4.7
通讯作者：
BIESENBE.JA
中科院分区：
文献类型：
--
作者：
SACKS, ME;LEE, SI;BIESENBE.JA
应用最大原理确定了在间歇反应器中使链加成聚合的分子量分布（MWD）宽度最小和最大的温度变化类型。结果表明，使随钻宽度最小的变化使瞬时数平均链长保持不变。使MWD宽度最大化的变化是温度的阶跃变化，导致双峰分布。给出了这种变化的数值和实验实例。将最小和最大宽度的随钻曲线与实际反应堆中温度变化可能形成的随钻曲线进行比较。在大多数情况下，温度变化似乎比停留时间分布和微混合对随钻测井的影响要大得多。
The Maximum Principle was applied to determine the types of temperature variations that minimize and maximize the breadth of the molecular weight distribution (MWD) for chain addition polymerizations in batch reactors. It was found that the variations which minimize the breadth of the MWD keep the instantaneous number average chain length constant. The variations which maximize the breadth of the MWD are step changes in temperature resulting in bimodal distributions. Numerical and experimental examples of such variations are presented. MWD's with minimum and maximum breadths are compared to those that might be formed by temperature variations in real reactors. Under most conditions, temperature variations appear to have a much greater effect on MWD than residence time distributions and micromixing.