快结晶聚的临界冷却速率:聚乙烯 (转化-1,4-环乙烯碳酸盐) 的例子
Kylian Hallavant1, Michelina Soccio2,3,4, Giulia Guidotti2
1INSA Rouen Normandie, CNRS, Groupe de Physique des Matériaux UMR 6634, University Rouen Normandie, F-76000 Rouen, France.
Polymers
|October 16, 2024
概括
控制聚合物冷却速率对于微观结构和性能至关重要. 这项研究确定了聚乙烯转-1,4-环二碳酸盐 (PCHs) 达到无形状态的关键冷却速度,发现偶数PCHs需要显著更快的速度.
科学领域:
- 材料科学 材料科学 材料科学
- 聚合物化学 聚合物化学
- 物理化学 物理化学
背景情况:
- 在聚合物制造中控制冷却速率是具有挑战性的,特别是对于薄或小的零件.
- 冷却速率显著影响聚合物微观结构和时间依赖性质.
- 传统的热量计方法仅限于缓慢的冷却速度 (几十度/分钟).
研究的目的:
- 为了估计融灭特定聚合物的临界冷却速率到完全无形状态.
- 为了研究化学结构对所需冷却速率的影响.
- 为了比较一系列聚乙烯转-1,4-环烯二碳酸盐 (PCHs) 的冷却速率要求.
主要方法:
- 使用了热量计技术的组合:差分扫描热量计 (DSC),调节温度的DSC,随机调节的DSC和快速扫描热量计.
- 研究了一系列具有不同甲基数量的PCH (nCH2=3至6).
- 确定了必要的临界冷却速率,以防止在融物冷却后结晶.
主要成果:
- 与奇数PCH相比,偶数PCH (nCH2=4,6) 需要显著更高的临界冷却速率 (高达3000K/s),而不是奇数PCH (nCH2=3,5).
- 具体的临界冷却速率为每个研究的PCH量化.
- 观察到甲基基数量与所需的冷却速率之间存在明显的相关性.
结论:
- 该研究成功估计了快速结晶的聚烯的临界冷却速率,以达到快速结晶的聚烯的无形状态.
- 通过了解这些关键的冷却速率,可以优化材料加工和财产控制.
- 这些发现突显了冷却速率控制在聚合物制造中对定制材料性能的重要性.
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