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聚尿素-石墨烯纳米复合材料 - - 硬分段含量和纳米粒子负载对机械性能的影响
Demetrios A Tzelepis1,2, Arman Khoshnevis3, Mohsen Zayernouri3,4
1Department of Chemical Engineering and Materials Science, Michigan State University, East Lansing, MI 48824, USA.
Polymers
|November 25, 2023
概括
该研究表明,调整硬段重量分数显著影响聚氨纳米复合材料的刚性. 除了在特定配方外,剥落石墨烯纳米板块 (xGnP) 的加载效果有限.
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
- 纳米技术纳米技术
背景情况:
- 聚氨和聚尿素粘合剂在汽车,电子和医疗领域至关重要.
- 了解配方-结构-特性关系是提高粘合剂性能的关键.
- 聚氨纳米复合材料为先进的应用提供可调节的特性.
研究的目的:
- 调查硬分段重量分数 (HSWF) 和脱皮石墨烯纳米板块 (xGnP) 负载对聚尿素纳米复合材料粘弹性特性的影响.
- 为了建立基于IPDI的聚尿素 (PUa) 矩阵与xGnP填充剂的配方-结构-特性相关性.
- 开发和验证一个基于物理的质模型来描述材料的行为.
主要方法:
- 使用扫描电子显微镜 (SEM) 和动态机械分析 (DMA) 进行表征.
- 在PUa纳米复合材料中的HSWF和xGnP负荷的系统变化.
- 基于微积分计算的风湿学模型的开发,以解释DMA数据.
主要成果:
- 从20%提高HSWF到40%,拉力储存模块 (刚度) 从10MPa大幅增加到250MPa.
- xGnP负荷对刚度的影响有限,除了20%的HSWF增长80%外.
- 开发的风学模型准确地描述了材料在广泛的温度 (-70 °C至 +70 °C) 和频率 (0.1-100 s-1) 范围内,具有六个参数的材料行为.
结论:
- HSWF是控制这些聚尿素纳米复合物的刚度的主要因素.
- 基于物理的风学模型为理解和预测材料反应提供了强大的框架.
- 这些发现为设计定制的聚氨纳米复合材料粘合剂提供了宝贵的指导.
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