Plastic heat resistance index and classification introduction---bathroom anti-fog mirror

Compared with traditional materials such as metals, ceramics, and glass, one of the shortcomings of plastics is their low heat resistance, which often limits their use in high-temperature situations. Among plastic materials, different types of plastics have different heat resistance; some have very low heat resistance, and some have higher heat resistance. Heat-resistant plastics generally refer to a type of plastic products whose heat distortion temperature is above 200°C. There are three indicators to measure the heat resistance of plastic products: heat distortion temperature, Martin heat resistance temperature and Vicat softening point. Among them, heat distortion temperature is the most commonly used. The relationship between the above three heat resistance indexes of the same plastic is as follows: Vicat softening point> heat distortion temperature> Martin heat resistance temperature. According to the heat resistance of the plastic, plastics are divided into the following four categories: ① Low heat resistance plastic heat distortion temperature A type of resin below 100°C. Specific varieties are: PE, PS, PVC, PET, PBT, ABS and PMMA, etc. ②A type of resin whose heat distortion temperature is between 100 and 200℃ for medium heat-resistant plastics. Specific varieties are: PP, PVF, PVDC, PSF, PPO and PC, etc. ③The heat distortion temperature of high heat-resistant plastics is between 200～300℃. The specific varieties are: the heat distortion temperature of polyphenylene sulfide (PPS) can reach 240°C, the heat distortion temperature of chlorinated polyether can reach 2l0°C, the heat distortion temperature of polyarylsulfone (PAR) can reach 280°C, and the heat distortion temperature of PEEK The heat distortion temperature can reach 230℃, the heat distortion temperature of POB can reach 260～300C, the heat distortion temperature of fusible PI is 270～280℃, the heat distortion temperature of amino plastic is 240℃, and the heat distortion temperature of EP can reach 230. ℃, the heat distortion temperature of PF can reach 200℃. ④Ultra-high heat-resistant plastics are a type of resin whose heat distortion temperature is greater than 300°C. There are few types, specifically: the heat distortion temperature of polyphenylester can reach 310℃, the heat distortion temperature of polybenzimidazole (PBI) can reach 435℃, and the heat distortion temperature of non-melting PI can reach 360℃. So which is the most resistant to high temperature? The long-term working temperature of polybenzimidazole PBI can reach 310℃, and the short-term use temperature can reach 500℃. Polybenzimidazole PBI is one of the most heat-resistant plastics, but the price is also the highest among plastics, and it is difficult to process. Therefore, the most heat-resistant plastic is polybenzimidazole PBI. Secondly, the most heat-resistant plastic should be polyimide PI. The long-term working temperature can reach about 290°C, and the short-term temperature can reach 480°C. It can work in an environment of -240°C. Other high temperature resistant materials, polyamide-imide PAI (also known as TORLON), is also a thermosetting plastic, long-term working temperature can reach 250 ℃, low temperature resistance is also excellent, TORLON has excellent wear resistance and impact resistance at the same time . Polyether ether ketone PEEK, long-term working temperature can reach 160℃, short-term working temperature can reach 260℃, enhanced grades have better high temperature resistance. Polyetherimide PEI, the long-term working temperature can reach 170℃, and the short-term working temperature can reach 200℃. The long-term working temperature of polyphenylene sulfide PPS can reach 220℃, and the short-term working temperature can reach 260℃. The long-term working temperature of polyvinylidene fluoride PVDF can reach 150℃, and the short-term working temperature can reach 160. At the same time, it has excellent corrosion resistance, and has high mechanical strength and rigidity. PTFE PTFE has a long-term working temperature of 260°C and a short-term working temperature of 280°C. It has excellent corrosion resistance and is commonly known as the 'Plastic King'. It also has a very low coefficient of friction. The long-term working temperature of polysulfone PSU is 150℃, and the short-term working temperature can reach 180℃. Polysulfone PSU also has good comprehensive electrical properties. PES performance is similar to PSU, the working temperature is higher, the long-term working temperature is 180℃, and the short-term working temperature is 220℃. Nylon 46, long-term working temperature can reach 135℃, has excellent toughness and good chemical resistance. Bathroom anti-fog mirror