What is an antioxidant? Antioxidants are a class of chemicals that, when present in small amounts in a polymer system, retard or inhibit the oxidation of the polymer, thereby preventing aging of the polymer and extending its useful life. Anti-aging agent." Antioxidants are widely used in plastic processing. "If you want to do something good, you must first sharpen your tools." As a practitioner, you must have a deep understanding of it, you can use it well, and introduce you to the knowledge of antioxidants. Types of antioxidants: (1) Phosphorus antioxidant Phosphite acts as a secondary antioxidant, with TNPP and 168 being the main general-purpose varieties. (2) Phenolic antioxidants Phenolic antioxidants are the most widely used and most widely used antioxidants in plastics. (3) sulfur antioxidants Compared with phosphorus antioxidants, the development and application of sulfur antioxidants is very monotonous, and thiopropionates still dominate. (4) Natural antioxidants As a safe and effective measure, on the one hand, high-molecular-weight hindered phenols with high efficiency and heat resistance are continuously developed and applied, and on the other hand, natural non-toxic antioxidants are put into practice. (5) Polymeric phenolic antioxidant WINGSTaY® L Antioxidant is a highly effective polyphenolic additive with high activity and low volatility. WINGSTaY L does not discolor and does not turn red. (6) Compound antioxidant Composite additives have become one of the main trends in the development of plastic additives industry. High-efficiency composite antioxidants are complexes of hindered phenols with phosphites and thioesters, as well as hindered phenolic antioxidants and UV absorption. Compound product. (7) Metal ion passivator The ion-passivating agent is mainly composed of bis-salicylidene diamine. From the perspective of its variety development trend, multi-functionality is its main feature. Functional metal ion deactivators are mostly products with bonded hindered phenol functional groups. At the same time, the article is imparted with copper resistance and thermal aging resistance. The role of antioxidants: (1) Function of antioxidants on the processing of modified plastic products The processing of plastic materials or products not only directly has a negative effect on the physical properties, mechanical properties, appearance and color of the polymer, but also has an important influence on the stability of the material or the process of the product. For varnish manufacturers, phosphite antioxidants should be used. The addition of plastic masterbatch to the resin to produce various types of modified plastic products, as well as the use of some secondary plastics (edges and corners produced by the company) processed products, has been widely used in the plastics processing industry. For the modified plastic products which are processed and produced by adding the masterbatch, the carrier resin used for the production of the master batch is thermally degraded and mechanically degraded again after being subjected to heat extrusion in the production process of the modified plastic product, and further Initiating or accelerating the heat and oxygen aging reaction of plastic products during use. Therefore, although the proportion of the carrier resin in the masterbatch is not large in the modified plastic product, the thermal oxygen aging problem caused by the secondary or secondary heating, and the influence on the aging performance of the product during use should be Lead to the attention of modified plastics processing enterprises and masterbatch manufacturers, phosphite antioxidants should be used. (2) Function of antioxidants on the use of modified plastic products Among the antioxidants that protect the polymer for long-term thermo-oxidative stabilization, hindered phenolic antioxidants are the most important ones, and they can be used alone or in combination with thioester-assisted antioxidants. The toughened modified Pa6 material for automotive engine parts can effectively improve the heat-resistant oxygen aging performance of the process by adding an antioxidant. (3) Effect of antioxidants on VOC of modified plastic products The World Health Organization defines VOC as a volatile organic compound having a melting point below room temperature and a boiling point between 50 and 260 °C. Benzene, toluene, methanol and other organic substances conforming to VOC definition are solvents used in the reaction process and crystallization process of some varieties of antioxidants, and will inevitably remain in antioxidant products. In the product quality analysis indicators of plastic additives such as antioxidants, there are generally “heat reduction†(or volatile) items. If the amount of antioxidant added in the modified plastic product is 0.2%, the antioxidant is heated. The maximum amount of reduction is 0.5%, and the maximum amount of volatile organic compounds is about 0.001% (10 ppm) by weight of the product. If the weight of the modified plastic product is one kilogram (1Kg) and placed in a space of 2 cubic meters (2m3), the maximum amount of volatile organic compounds can be about 10 milligrams (10mg), which is equivalent to 5mg/m3. In order to ensure that the modified plastic products such as vehicles meet the VOC limits of developed countries or foreign developed countries, when using antioxidants (or other additives), the heating reduction of the products should be strictly controlled. It is recommended to use or require heating reduction ≤ 0.1 %. Moreover, in the production process of modified plastic products, processing equipment with good exhausting means is used. The antioxidant is added to the modified plastic material, which can effectively inhibit or reduce the thermal oxidation reaction speed of the plastic macromolecule, delay the degradation and aging process of the plastic material, and significantly improve the heat resistance of the plastic material. Therefore, the modified plastic material can appropriately reduce or delay the influence of the modified plastic product on the overall VOC by using a suitable and suitable antioxidant. Chain Sling Hook,Chain Block Hook,3 Leg Chain Sling,4 Leg Chain Guangdong Gongyou Lift Slings Machinery CO.,LTD , https://www.wmpallettruck.com