According to the degree of polymerization and other differences, PVC can be divided into general Resin (sg-1-sg-8) and special / special resin.
1、 General purpose Pvc Resin
In China's general PVC Series in 2019, type 5 materials account for about 77%, which is lower than about 80% of the previous two years. The output of type 7 and type 8 materials increased rapidly, and the output of type 8 materials was mainly produced by calcium carbide enterprises, while that of type 7 materials was more produced by ethylene enterprises. The analysis shows that the reason for this feature is that type 7 materials have higher requirements for transparency in sheet materials, floor covering, especially in medical aspects. Ethylene method PVC is better than calcium carbide in this feature, and it is also one of the varieties with competitive advantages and characteristics of ethylene method PVC.
2、 Special / special PVC Resin
There are many kinds of special PVC and special PVC products, and their consumption fields are wide. The concept of special PVC and special PVC is general, and there is no strict boundary.
The basic concept is to improve or increase the function of PVC through physical, chemical, physical and chemical combination, or even mechanical methods, through copolymerization, homopolymerization, blending, filling, reinforcement and other methods, in terms of electrical, magnetic, optical, thermal, aging resistance, flame retardant, mechanical properties and other plastic materials, People expect to change or give the material the function to use in special environmental conditions to get new materials. With the progress and development of science and technology in other industries, new requirements for PVC materials are constantly put forward, and new special or special PVC resins will continue to appear.
At present, PVC Paste Resin, chloroacetate resin, PVC matting resin, high degree of polymerization / ultra-high degree of polymerization PVC resin, low degree of polymerization / ultra-low degree of polymerization PVC resin, partial chlorine resin and chlorinated PVC have a certain capacity in China. At present, the output of PVC special resin in China is relatively small, the market development is difficult, and the market is still in the cultivation stage. According to the statistical calculation, the current consumption of PVC special resin in China accounts for 2.4% of the total consumption of PVC (except paste resin).
In the future, one of the important directions of PVC resin development in China is to focus on the development of special PVC and special PVC. From the perspective of upstream and downstream integration, PVC manufacturers can quickly understand the market demand, so as to reasonably plan their own products, meet the needs of customers, and achieve a win-win situation of upstream and downstream.
According to the market demand, we develop and produce all kinds of PVC special materials, composite materials and additive resins which are more suitable for the improvement of product performance and easier to process. At present, some PVC enterprises mainly consider the following five categories: 1) low polymerization degree and ultra-low polymerization degree resins; 2) low polymerization degree resins; 2) Special resin for pipes and profiles with high apparent density; 3) Super high degree of polymerization resin with degree of polymerization above 1700; 4) Matting resin with modifier added in polymerization; 5) High impact resins and high impact resins grafted with monomers.
