多重晶体生长率的定量模型 聚合物中的最小值与有规律间隔的替代组的聚合物
Kutlwano Gabana1, Gillian A Gehring1, Xiangbing Zeng2
1Department of Physics and Astronomy, University of Sheffield, Sheffield S3 7RH, U.K.
Macromolecules
|March 4, 2024
概括
一个新的理论解释了聚乙烯铜酸 (PEBs) 中的晶体生长率最小值. 这些异常是由自我中毒引起的,在这种情况下,短的聚合物茎暂时阻碍了生长.
科学领域:
- 聚合物科学 聚合物科学
- 材料科学是一种材料科学.
- 结晶运动的动力学
背景情况:
- 聚乙烯铜酸 (PEBs) 呈现出不寻常的多重晶体生长率最小值.
- 这些最小值与特定的折叠长度和化学缺陷 (二基) 有关.
研究的目的:
- 开发一种定量理论来解释PEB中观察到的晶体生长率最小值.
- 为了验证聚合物晶体生长的自我中毒假设.
主要方法:
- 开发了一种分析速率方程模型,包括单体附着,脱离和茎延长.
- 将模型应用于不同分子量PEB的实验结晶率数据.
主要成果:
- 该模型准确地复制了PEBs的实验结晶率曲线.
- 定量匹配证实,自我中毒是最低速率的原因.
- 确定了短而不稳定的茎,作为自我中毒的来源.
结论:
- 开发的理论量化解释了PEBs中的晶体生长异常.
- 自我中毒是聚合物晶体生长前端的一个普遍现象.
- 这些发现将有助于更好地理解聚合物结晶和叶片生长动力学.
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