Physical Properties of Polyurethane Screens in Extreme Temperatures and Environments

When screening materials in regions with drastic temperature fluctuations, the performance of polyurethane screens differs significantly from most people's expectations. They perform well in extreme high and low temperatures, directly impacting whether your equipment can withstand the entire season.

How High Temperatures Change Polyurethane Screens

Above 80°C, the tensile strength of most polyurethane screens begins to decrease. The material softens, and the porosity decreases, affecting particle size analysis results. At sustained high temperatures, hydrolysis begins—moisture in the air breaks down the bonds in the polyurethane from the inside. Screens that appear intact on the surface may crack within weeks.

Low-Temperature Performance is Equally Challenging

Many buyers are surprised to find that polyurethane screens not only harden at low temperatures but also become brittle. Below -20°C, their impact resistance drops drastically. Screens that are flexible at room temperature may crumble at the slightest touch in the harsh winters of Northern Europe. Screens rated for -40°C require the use of special polyether polyols to ensure their Tg is significantly lower than the operating temperature range.

Important Factors When Selecting Screens

Don't just look at hardness when selecting screens. To choose a suitable polyurethane screen, consider three indicators: tensile strength retention at extreme temperatures, abrasion resistance after thermal cycling, and elongation at break under low-temperature conditions. The actual physical properties of polyurethane screens in extreme high and low temperature environments are only revealed after multiple thermal cycles.

Standard polyurethane screens perform well in mild climates. However, if the temperature exceeds ±40°C, other materials need to be considered. Screen specifications should consider not only the application scenario but also environmental and temperature factors.