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通过动态振荡剪切测试来区分线性和星状聚烯与未纠的臂
Hyeong Yong Song1, Seung Joon Park2, Kyu Hyun1
1School of Chemical Engineering, Pusan National University, Busan 46241, Republic of Korea.
ACS macro letters
|June 30, 2023
概括
不纠的恒星聚乙烯 (PS) 化物表现出类似于线性链的线性粘性弹性. 然而,恒星PS在不纠的状态下表现出比线性PS更高的内在非线性,正如中幅振荡剪切试验所示.
科学领域:
- 聚合物物理 聚合物物理
- 类风病学 类风病学 类风病学
- 材料科学 材料科学 材料科学
背景情况:
- 了解聚合物的粘弹性特性对于预测它们在各种应用中的行为至关重要.
- 与线性聚合物相比,具有独特架构的星聚合物可能会表现出明显的粘弹性反应.
- 区分线性和非线性粘弹性模式对于描述聚合物化的特性至关重要.
研究的目的:
- 为了研究和比较不纠的星聚乙烯 (PS) 融的线性和非线性粘弹性,与纠的线性和星PS融的线性和非线性粘弹性.
- 确定Lihktman-McLeish和多模K-BKZ模型是否可以准确地描述未纠的恒星聚合物的行为.
- 阐明未纠的恒星和线性PS之间的内在非线性差异.
主要方法:
- 小振幅振荡剪切 (SAOS) 和中振幅振荡剪切 (MAOS) 测试对未纠的恒星PS,纠的线性PS和纠的恒星PS炼进行了测试.
- 使用放松光谱分析了线性粘弹性特性,并与Lihktman-McLeish模型进行了比较.
- 使用相对内在非线性 (Q0) 评估非线性粘弹性特性,并与多模K-BKZ模型进行比较.
主要成果:
- 没有纠的恒星PS的线性粘弹性特性被Lihktman-McLeish模型量化描述,类似于纠的线性链,表明通过放松光谱无法区分.
- 相对的内在非线性 (Q0) 显示了不纠的恒星和线性PS之间的明显差异.
- 不纠的恒星PS表现出比线性PS更高的最大相对内在非线性 (Q0,max) 值,与多模K-BKZ模型的预测一致.
结论:
- 在未纠的状态下,星状聚烯与线性聚烯相比,表现出本质上更高的相对非线性.
- 虽然线性粘弹性不区分无纠的恒星和线性链,但非线性粘弹性确实可以区分.
- 这些发现凸显了在非线性风湿学表征中考虑聚合物结构的重要性.
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