PC (polycarbonate) sheets are subject to aging due to ultraviolet radiation, so PC sheet manufacturers have adopted different methods to solve this problem in order to extend the service life of the sheet. At present, the most practical and effective method is to add ultraviolet absorbers (abbreviated as UV materials) to the product. According to different production processes, there are three ways to add UV materials: mixed addition method, coating method and co-extrusion method.
1.Mixed addition method
A certain proportion of UV material (about 5%) is mixed into the PC material, and then melted and extruded at a high temperature. However, most of the plates processed by this method are still exposed to the sun, so the aging of the plate surface is still unavoidable.
2.Coating method
Coat a layer of UV material on the surface of the board. However, due to the poor compatibility of PC and other materials, rainwater can easily wash away the coating on the surface of the board after installation. In addition, considering that the board may be damaged during storage and transportation, both sides of the board are covered with a protective film during production. The protective film must be torn off after installation, and because the protective film is sticky, a large amount of UV material coated on the surface will stick during the tearing process, so the actual effect is relatively poor.
3.Coextrusion
At present, the most advanced method in the world is the co-extrusion method. In this method, the PC main material and UV material are melted and extruded at high temperature in an extruder, merged in the mold, and then drained through the runner in the mold to form a dense protective layer on the surface of the PC. However, changes in temperature, speed, pressure, etc. in actual production using this method will affect the distribution of UV materials on the surface of the sheet, making the thickness uneven across the width of the sheet.
Company Name: Baoding Xinhai Plastic Sheet Co.,ltd
Contact Person: Sale Manager
Email: admin@cnxhpcsheet.com
Phone: +8617713273609
Country: China
Website: https://www.xhplasticsheet.com/
Post time: Dec-10-2021