Optical properties of PMMA 1, visible light: high transmittance of visible light. PMMA is the best polymer transparent material at present, and its visible light transmittance is 92%, which is [1] higher than that of glass. 1. ultraviolet light: quartz can be completely ultraviolet light, but the price is high, ordinary glass can only pass through 0.6% ultraviolet ray, but PMMA can pass through 73%. PMMA can't filter out ultraviolet (UV). Ultraviolet light penetrates PMMA, and part of the manufacturer [2] is coated on the surface of the PMMA to increase the effect and properties of the UV light. On the other hand, PMMA has better stability than polycarbonate in the condition of ultraviolet light irradiation. 2. infrared: PMMA allows infrared rays less than 2800nm wavelengths to pass through. Longer wavelengths of IR, less than 25000nm, are basically blocked. There is a special colored PMMA that allows a specific wavelength of IR to pass through and block visible light, (used for remote control?or?heat, etc.). The POM enhanced POM The main reinforcement materials are glass fiber, glass ball?or?carbon fiber, and glass fiber is most commonly used. The mechanical properties of the reinforced glass can be increased by 2~3 times and the hot deformation temperature is increased by 50 degrees?or?more. The high oil POM Adding graphite, F4, molybdenum disulfide, lubricating oil and low molecular weight PE to POM can improve its lubrication performance. For example, adding 5 copies of F4 in POM can reduce the friction factor by 60%, and increase the wear resistance by 1~2 times. In addition, the addition of liquid lubricating oil in POM can greatly improve the wear resistance and the limit of PV. In order to improve the dispersing effect of oil, the oil absorption carrier, such as carbon black, barium hydroxide, and ethylene propylene rubber, should be added. The friction of adding 5% oil POM is increased by 72%, and the limit PV can reach 3.9MPa m/s (pure POM is 0.213MPa m/s), which is 3~20 times that of other engineering plastics. PPO B has good electrical properties in a wide range of temperature and frequency. It has no hydrolysis and shrinkage, and has no self extinguishment. It is resistant to inorganic acid, alkali, aromatic hydrocarbon, halogenated hydrocarbon and oil. It is prone to swelling?or?stress cracking. C, it has the advantages of large rigidity, high heat resistance, refractory, high strength and so on. D and polyether have the advantages of wear-resistant, non-toxic, and resistant to pollution. Dielectric constant and dielectric loss of E and PPO plastic materials are among the smallest varieties in engineering plastics. They are hardly affected by temperature and humidity. They can be used in low, medium and high frequency electric fields. The load deformation temperature of F and PPO can reach more than 190 degrees C, and the embrittlement temperature is -170 C. G, its main shortcomings are poor melt fluidity and difficult processing.。