核心外塑料纳米颗粒修饰的CFRP/钢环境固化粘合剂关节:固化动力学和机械行为
Abass Abayomi Okeola1, Jorge E Hernandez-Limon1, Jovan Tatar2
1Department of Civil and Environmental Engineering, University of Delaware, Newark, DE 19716, USA.
Materials (Basel, Switzerland)
|April 9, 2024
概括
核心外 (CSR) 纳米颗粒提高了柔性,并显著提高了碳纤维增强聚合物 (CFRP) 接钢的环氧粘合剂的剪切强度,克服了钢结构维修方面的挑战.
科学领域:
- 材料科学 材料科学 材料科学
- 结构工程 结构工程
- 聚合物化学 聚合物化学
背景情况:
- 外接碳纤维增强聚合物 (CFRP) 系统对于混凝土而不是钢结构是常见的.
- 湿CFRP与钢基板的粘合存在挑战.
研究的目的:
- 研究核心外 (CSR) 纳米颗粒对CFRP/钢接头的环氧粘合剂的影响.
- 评估CSR对固化动力学,玻璃过渡温度 (Tg) 和机械性能的影响.
- 评估西兰合剂和CSR对粘合剂粘合性能的影响.
主要方法:
- 环境固化环氧/CSR混合物的配方,含有不同的CSR含量.
- 环氧/CSR混合物的固化动力学和Tg的表征.
- 整洁环氧和改性粘合剂 (拉伸强度,模量,可塑性) 的机械测试.
- 评估CFRP/钢单层剪接接头,用整洁和修改的粘合剂粘合.
主要成果:
- CSR纳米粒子对环氧固化动力学表现出轻微的催化作用.
- 添加CSR对环氧的玻璃化过渡温度 (Tg) 有微不足道的影响.
- 具有5-20%重量的环氧粘合剂. CSR显示柔性得到改善,但拉伸强度和模量降低.
- 与CSR修改的CFRP/钢接头相比,与整洁的环氧接头相比,单环切割强度增加了高达250%.
结论:
- CSR纳米颗粒可以增强柔性,并显著提高环氧粘合剂的剪接强度,用于钢结构的CFRP增强.
- 对于CFRP-to-steel应用,CSR修改提供了一种有希望的方法来克服粘合挑战.
- 进一步的研究可能会优化企业社会责任内容,以平衡强度,柔性和结合性能.
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