In recent years, more and more attention has been paid to the influence of humidity on polymer materials. One of the scenes is the influence of humidity on the reliability of equipment in the field of microelectronics and MEMS, such as swelling and deformation of materials, cracking and stress concentration. The second is the aging problem of polymer materials in engineering application, which will reduce the function of polymer materials.

Influence of humidity on engineering plastics

Therefore, the relative humidity of the material used in the outer surface is greater than 80% of the moisture content in the plastic film; When the relative humidity in the air is less than 50%, the moisture in the plastic will evaporate into the air, which will also change the function of the plastic, making some plastics brittle and crack.

The effect of humidity on the function of engineering plastics is the process of infiltration to absorption. At present, there are two aspects in the study of the influence of humidity on the structure and mechanical function of plastics. On the one hand, the material deformation and residual stress caused by the swelling caused by humidity are discussed, including the structural stress and interface stress caused by moisture infiltration, dispersion and uneven moisture content by means of constitutive or numerical simulation; On the other hand, the effects of humidity and temperature on the physical properties of plastics, such as strength, density, modulus and longevity, are discussed.

The influence of environmental humidity on the function of plastic machinery is significant. Generally, plastics that can absorb water are sex materials. These materials can form some kinds of bonds, which may be hydrogen bonds, such as nylon and other materials. On the other hand, moisture has no effect on polyethylene or polytetrafluoroethylene, and the function of these plastics is almost indolent with regard to changes in ambient humidity.

Source: Jiangmen engineering plastics http://www.iuk8.cn/