调节聚氨复合材料中核心-外-颗粒的交联结构和分散,以实现结构粘合剂应用的优良机械性能
Zijin Jiang1,2, Lingtong Li1, Luoping Fu2
1The State Key Laboratory of Polymer Materials Engineering, Polymer Research Institute of Sichuan University, Chengdu 610065, China.
Polymers
|December 17, 2024
概括
这项研究开发了一种新的聚氨 (PU) 复合结构粘合剂. 通过优化交叉连接和结合核心-- (CSR) 颗粒,粘合剂表现出优越的性,快速固化和优异的环境耐受性,适用于苛刻的应用.
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
背景情况:
- 耐热聚氨结构粘合剂具有局限性,包括性差,耐老化性和缓慢固化时间.
- 这些缺点限制了它们在结构粘合和维修中的广泛实际应用.
研究的目的:
- 开发一种高性能聚氨 (PU) 复合结构粘合剂,具有增强的机械性能,快速固化和更好的耐用性.
- 通过结构修改和颗粒分散来解决传统聚氨粘合剂的局限性.
主要方法:
- 调节PU的交叉连接结构,使用各种聚合物来增加交叉连接密度和分子间力量.
- 通过溶剂移位,改善PU矩阵内核心- (CSR) 颗粒的分散.
- 包含催化剂T120用于在室温下快速固化.
主要成果:
- 修改后的PU复合材料表现出显著增强的性和抗冲击能力,冲击强度从52.0增加到90.4kJ/m2,断裂时的延长从6.1%增加到14.9%.
- 在30分钟内在室温下实现了快速固化,达到高强度.
- 复合材料对极端环境条件,包括温度波动,紫外线老化,湿度,热量和盐雾等表现出极好的抗性.
结论:
- 开发的PU复合结构粘合剂为创造具有卓越机械性能和耐久性的材料提供了一种新的策略.
- 增强型粘合剂满足运输中的结构粘合的要求,并提高了生产效率.
- 这种材料显示出实际应用的巨大潜力,要求强大而有弹性的粘合解决方案.
相关概念视频
01:14Polymer Classification: Architecture
2.6K
Polymers are classified as linear or branched on the basis of their chain architecture. The polymer chains in linear polymers have a long chain-like structure with minimal to no branching at all. Even if a polymer features large substituent groups on the monomer, which appear as branches to the skeleton, it is not considered a branched polymer. A branched polymer contains secondary polymer chains that arise from the main polymer chain. The branching occurs when the polymer growth shifts from...
2.6K
01:30Superplasticizers
77
Superplasticizers are advanced admixtures that enhance the workability of concrete by lowering the water content without compromising the strength of the material. These substances are highly effective water reducers, improving concrete flow, making it easier to work with, and enabling concrete to reach inaccessible areas or densely reinforced sections without mechanical vibration. The key components in superplasticizers are either sulfonated melamine or naphthalene formaldehyde condensates,...
77
01:31Plasticizers
65
Water-reducers, or plasticizers, are chemical admixtures used in concrete to improve strength and workability. These additives reduce the water-cement ratio without compromising workability, lower the cement content while maintaining the same workability, or increase workability to assist concrete placement in inaccessible areas.
Plasticizers function by using surface-active agents to create repulsive electrostatic forces between cement particles. This dispersion enhances the concrete's...
Plasticizers function by using surface-active agents to create repulsive electrostatic forces between cement particles. This dispersion enhances the concrete's...
65
00:53Olefin Metathesis Polymerization: Acyclic Diene Metathesis (ADMET)
1.9K
Acyclic diene metathesis polymerization or ADMET polymerization involves cross-metathesis of terminal dienes, such as 1,8-nonadiene, to give linear unsaturated polymer and ethylene. As ADMET is a reversible process, the formed ethylene gas must be removed from the reaction mixture to complete the polymerization process.
Similar to cross-metathesis, ADMET also involves the formation of metallacyclobutane intermediate by [2+2] cycloaddition of one of the double bonds of a terminal diene with...
Similar to cross-metathesis, ADMET also involves the formation of metallacyclobutane intermediate by [2+2] cycloaddition of one of the double bonds of a terminal diene with...
1.9K
01:29Additives and Fillers in Concrete
89
Additives and fillers are integral to enhancing the properties of concrete. Pozzolans and blast-furnace slag are additives or admixtures due to their reactions with calcium hydroxide released during cement hydration. Fillers, which are finely ground and similar in fineness to Portland cement, improve concrete attributes such as workability density, and reduce capillary bleeding or cracking. Some fillers possess hydraulic properties or participate in benign reactions within the cement paste.
The...
The...
89
01:19Retarders
61
Retarders are chemical admixtures designed to extend the setting time, which is especially useful when there is a delay in sequential concrete pours to prevent cold joints and to achieve a cohesive structure. Retarders, when used in appropriate amounts, can also enhance the architectural appearance of exposed aggregate finishes.
The function of retarders is to delay the setting of concrete, and this effect can be measured using a penetration test. The retardation process involves adding...
The function of retarders is to delay the setting of concrete, and this effect can be measured using a penetration test. The retardation process involves adding...
61