在超临界二氧化碳挤出发泡过程中TPU/EVA阶段形态演化的影响
Jun-Wei Du1, Tian-Tian Zhou1, Rong Zhang1
1Hubei Provincial Key Laboratory of Green Materials for Light Industry, Hubei University of Technology, Wuhan 430068, China.
Polymers
|July 29, 2023
概括
将乙烯乙酸共聚合物 (EVA) 添加到热塑性聚氨 (TPU) 中,可以改善发泡特性. 10%的EVA获得了最佳结果,在泡材料中产生了高细胞密度和小细胞大小.
科学领域:
- 材料科学 材料科学 材料科学
- 聚合物科学 聚合物科学
背景情况:
- 热塑性聚氨 (TPU) 和乙烯基乙烯酸共聚合物 (EVA) 是广泛使用的聚合物.
- 开发具有受控毛孔结构的先进泡材料对于各种应用至关重要.
研究的目的:
- 研究乙烯-乙酸共聚合物 (EVA) 含量对热塑性聚氨 (TPU) 发泡行为的影响.
- 了解混合物形态与由此产生的孔隙结构和泡TPU/EVA材料的特性之间的关系.
主要方法:
- 制备的TPU/EVA混合物与不同的EVA含量.
- 使用超临界二氧化碳挤出进行泡.
- 分析相位形态,晶体形态,融粘度和结晶性.
- 细胞大小,细胞密度,细胞厚度和整体泡性质的表征.
主要成果:
- 添加EVA改变了TPU矩阵的相位和晶体形态,提高了融的粘度和结晶性.
- 由EVA诱导的界面核化增加了细胞密度,同时减少了细胞厚度和大小.
- 10% (质量分数) 的最佳EVA含量产生了最高的细胞密度 (3.74 × 10^6细胞/cm^3) 和最小的细胞大小 (105.29 μm).
- 与双连续结构相比,海岛形态表现出优越的泡特性.
结论:
- TPU/EVA混合物的形态和结晶性显著影响发泡行为.
- 埃瓦作为核化剂,促进细致和密集的细胞结构的形成.
- 海岛形态有利于从TPU/EVA混合物中获得高性能泡材料.
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