Modified plastics refer to plastics that are processed and modified by filling, blending and other methods in resins of general plastics (PE, PP, PVC, PS, ABS) and engineering plastics (PA, PC, POM, PBT, PPO) to make them have better properties such as flame retardant, impact resistance and easy processing.
Modified plastics overcome the defects of ordinary plastics such as poor heat resistance, low strength and toughness, weak wear resistance, but also given new characteristics such as flame retardant, weather resistance, antibacterial, antistatic, chemical resistance, electrical conductivity, wear resistance, thermal conductivity and so on. The superior comprehensive properties of modified plastics make them widely used in household appliances, automobiles, communications, medical, electronic and electrical, rail transit, precision instruments, home building materials, security, aerospace and other fields.
Plastic modification rate refers to the percentage of the total production of modified plastics in the total production of plastics (including modified plastics and unmodified resins), which is an important indicator of the development level of plastic industry in a country or region.
At present, the annual output of the modified plastics in Chinese industrial enterprises above scale is more than 20 million tons, with the modification rate accounting for about 22%. Although this is related to the large output of Chinese base resins, there is still more room for improvement compared with the global plastics modification rate of nearly 50%.
In the process of plastic modification, functional auxiliaries are the core elements to achieve resin modification, which can often play the role of four or two dial a thousand jin, the Midas touch! At present, the hottest and most commonly used plastic functional additives are flame retardant, weather resistance agent, conductive agent, reinforcing agent, wear-resisting agent, antibacterial agent, anti-hydrolysis agent and so on.
Flame retardant is the second largest amount of plastic additives, in addition to the requirements of conventional flame retardant, for different application scenarios and resins, also put forward requirements for other properties, such as ultra-high flame retardant, halogen-free, thin-walled, high CTI, high heat resistance, low temperature resistance, high impact, precipitation resistance, high transparency……
Weather resistant agents mainly include antioxidants and light stabilizers. The antioxidant can be divided into main antioxidant and coantioxidant; According to the mechanism, light stabilizer can be divided into: free radical trapping agent (mainly hindered amine light stabilizer HALS), ultraviolet absorber (UVA), light screen agent. However, there are also cautions in their actual use. For example, some antioxidants do not tolerate high temperature, and blocked amine light stabilizer HALS will cause PC degradation......
Conductive agents are important additives to realize anti-static or conductive plastics, mainly carbon materials, metal fibers, conductive polymers, etc. At present, the most commonly used is to add conductive carbon black, graphene, carbon nanotubes and other carbon materials. Generally, the surface resistivity of plastics is 10^12-10^16 ohm/sq, while the requirements of antistatic plastics are in the range of 10^6-10^9, and conductive plastics require surface resistivity below 10^5, which requires a large amount of conductive agent addition and a good dispersion technique.....
Conductive plastic lights the beads Photo: Jinhu Rili
However, additives are often encountered in the process of practical application of various problems, one is that no matter how small the addition, its characteristics can not reach the target value, such as PMMA thin wall transparent flame retardant is the industry has been a problem; Second, although the additives improve some aspects of its properties, but cause other properties to decline significantly, lose practical application value, such as conventional conductive carbon black will make material impact and other properties decline significantly. In addition, how to achieve synergistic effect and cost reduction is also an important topic of concern.
YIHOO POLYMER is a global supplier of additives for the modification of plastics and coatings, including UV absorbers, antioxidants, light stabilizers and flame retardants, which have been widely used by customers in Europe, the United States and the Asia-Pacific region.
Enquiries are welcome at any time: yihoo@yihoopolymer.com
Post time: May-18-2023