Purpose

The mechanical and tribological properties of polymers and polymer composites vary with different environmental conditions. This paper aims to review the influence of humidity/water conditions on various polymers and polymer composites' mechanical properties and tribological behaviors.

Design/methodology/approach

The influence of humidity and water absorption on mechanical and tribological properties of various polymers, fillers and composites has been discussed in this paper. Tensile strength, modulus, yield strength, impact strength, COF and wear rates of polymer composites are compared for different environmental conditions. The interaction between the water molecules and hydrophobic polymers is also represented.

Findings

Pure polymer matrices show somewhat mixed behavior in humid environments. Absorbed moisture generally plasticizes the epoxies and polyamides and lowers the tensile strength, yield strength and modulus. Wear rates of PVC generally decrease in humid environments, while for polyamides, it increases. Fillers like graphite and boron-based compounds exhibit low COF, while MoS2 particulate fillers exhibit higher COF at high humidity and water conditions. The mechanical properties of fiber-reinforced polymer composites tend to decrease as the rate of humidity increases while the wear rates of fiber-reinforced polymer composites show somewhat mixed behavior. Particulate fillers like metals and advanced ceramics reinforced polymer composites exhibit low COF and wear rates as the rate of humidity increases.

Originality/value

The mechanical and tribological properties of polymers and polymer composites vary with the humidity value present in the environment. In dry conditions, wear loss is determined by the hardness of the contacting surfaces, which may not effectively work for high humid environments. The tribological performance of composite constituents, i.e. matrix and fillers in humid environments, defines the overall performance of polymer composite in said environments.

中文翻译：

---

环境湿度/吸水率对聚合物和聚合物复合材料摩擦力学性能的影响——综述

目的

聚合物和聚合物复合材料的机械和摩擦学性能随不同的环境条件而变化。本文旨在回顾湿度/水条件对各种聚合物和聚合物复合材料的机械性能和摩擦学行为的影响。

设计/方法/方法

本文讨论了湿度和吸水率对各种聚合物、填料和复合材料的机械和摩擦学性能的影响。比较聚合物复合材料在不同环境条件下的拉伸强度、模量、屈服强度、冲击强度、摩擦系数和磨损率。还展示了水分子和疏水聚合物之间的相互作用。

发现

纯聚合物基质在潮湿环境中表现出某种程度的混合行为。吸收的水分通常会使环氧树脂和聚酰胺塑化并降低拉伸强度、屈服强度和模量。PVC 的磨损率在潮湿环境中通常会降低，而对于聚酰胺，磨损率会增加。石墨和硼基化合物等填料表现出低 COF，而二硫化钼颗粒填料在高湿度和水条件下表现出更高的 COF。随着湿度的增加，纤维增强聚合物复合材料的机械性能往往会降低，而纤维增强聚合物复合材料的磨损率则表现出某种程度的混合行为。随着湿度的增加，金属和高级陶瓷增强聚合物复合材料等颗粒填料表现出较低的 COF 和磨损率。

原创性/价值

聚合物和聚合物复合材料的机械和摩擦学特性随环境中存在的湿度值而变化。在干燥条件下，磨损损失由接触表面的硬度决定，这在高湿环境中可能无法有效工作。复合材料成分，即潮湿环境中的基体和填料的摩擦学性能决定了聚合物复合材料在所述环境中的整体性能。