Light damage to plastics: For most plastics, the most sensitive wavelength is 290-400nm. This is the ultraviolet region. The ultraviolet energy can destroy the chemical bonds of the polymer and initiate photooxidation or oxidation. Photodegradation causes malignant changes in physical and mechanical properties. At the same time, the formation of carbonyl-containing decomposition products and chromophores deepens the change in color. The mechanism of action of light stabilizers: (1) Light-shielding agent: It can absorb or reflect ultraviolet light, so that light cannot be directly transmitted into the inside of the polymer, thereby effectively suppressing photoaging. Such as TiO2, ZnO. (2) Ultraviolet absorber: It can strongly absorb ultraviolet light and convert its energy into harmless heat energy. Such as: benzophenones, benzotriazoles. (3) Quencher: The excitation energy can be removed from the excited polymer molecule to return it to a low energy state. Mainly metal complexes. (4) Radical Scavenger: Captures different free radicals to prevent or delay the photodegradation process. Such as hindered amines. The principle of selection of light stabilizer: can effectively eliminate or weaken the damage of ultraviolet light on the polymer, but has no effect on other properties of the polymer; has good compatibility with the polymer, does not volatilize, does not migrate, is not Water and solvent extraction; low absorption of visible light, no coloration, no discoloration; similar to the color of the polymer, does not change the color of the polymer after addition. The hot selling face masks content Disposable Face Mask with biomass graphene, Disposable Medical Face Mask , Kn95 Face Mask and Ffp2 Face Mask . These facial masks in stock with low price, high quality,fast delivery. The price of disposable Face Mask is very good which can meet your demand. The face mask is suitable for indoor and outdoor use and is recommended when performing social activities or when close contact is necessary. Welcome to contact us anytime and cooperate with us. Face Mask,Disposable Face Mask,Disposable Graphene Face Mask,Protection Face Mask Shandong Shengquan New Materials Co., Ltd. , https://www.sqnewmaterials.com