气候衰老中的尺寸效应 环氧基岩纤维增强棒的气候衰老中的尺寸影响
Anna A Gavrilieva1, Oleg V Startsev1,2, Mikhail P Lebedev2
1Siberian Branch of the Russian Academy of Sciences V.P. Larionov Institute of Physical and Technical Problems of the North, 1 Oktyabrskaya Str., 677000 Yakutsk, Russia.
Polymers
|September 28, 2024
概括
压环氧基岩纤维钢筋条的尺寸显著影响了它们的气候老化. 直径较小的条块经历了更大的潮湿效应和强度降低,而较大的条块则表现出较少的降解,突出显示了尺寸对材料耐用性的重要性.
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
- 复合材料 复合材料 复合材料
背景情况:
- 聚复合材料,如环氧玄武纤维增强条,容易受到环境退化的影响.
- 气候老化,特别是吸收水分和温度波动,可以显著改变材料的性能.
- 了解材料尺寸对衰老的影响对于预测长期性能至关重要.
研究的目的:
- 为了研究条形直径对压环氧基岩纤维钢筋条的气候老化的影响.
- 分析湿度转移的动力学及其对不同气候条件下的材料性能的影响.
- 为了确定尺寸如何影响长时间暴露于环境后的机械强度,热膨胀和玻璃过渡温度.
主要方法:
- 具有不同直径 (6-20毫米) 的环氧基岩纤维增强条的样本在28-54个月内暴露在极寒 (雅库茨克) 和适度温暖 (盖伦吉克) 的气候中.
- 湿度转移动力学研究使用加湿和干燥在60°C,模拟的2D Langmuir模型.
- 暴露后测量了机械性能 (拉力,压力,曲强度),线性热膨胀系数和玻璃过渡温度.
主要成果:
- 扩散系数在强化方向显著高于辐射方向,随着杆子直径的变化而变化.
- 湿度透对较小直径条 (6毫米) 的强度的影响比较大.
- 更小的直径条显示变形性降低,玻璃过渡温度显著增加,表明更大的老化效应和额外的聚合物矩阵固化.
结论:
- 条形直径是一个关键因素影响气候衰老的脉冲环氧玄武岩纤维增强条.
- 潮湿塑化显著降低了较小直径条的强度,而较大的条则受到影响较小.
- 在较小的条中观察到的玻璃过渡温度的增加表明,由于水分相互作用和热循环,增强了聚合物矩阵固化.
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