1, Introduction
Polypropylene, also known as ethylene-propylene rubber (EPR), is a kind of poly rubber with ethylene and propylene as basic monomers after the invention of Ziegler-Natta catalyst and the appearance of polyethylene and polypropylene. It can be divided into two categories: ethylene propylene diene monomer (EPM) and ethylene propylene terpolymer (EPDM). The former is a polymer of ethylene and propylene, and the latter is a polymer of ethylene, propylene and a small amount of non-conjugated diene.
PPE is polypropylene. Generally speaking, commercially available PPE materials are generally mixed with other thermoplastic materials such as PS (styrene), PA (polyamide, commonly known as nylon) and other composite materials. It has good geometric stability, chemical stability, electrical insulation and low thermal expansion coefficient. This material is usually used in household goods (dishwashers, washing machines), electrical equipment and so on.
2. Features
It has many excellent properties that other general synthetic rubber does not have, and the monomer is cheap and easy to get, so it is widely used. It is one of the seven fastest-growing foreign synthetic rubber varieties since 1980s, and its output, capacity and consumption rank third in developed countries, second only to styrene-butadiene rubber and cis-butadiene rubber.
1998 The total global EPR production capacity is about/kloc-0.02 million tons, and the consumption is 8/kloc-0.40 million tons. According to preliminary statistics, the consumption of1000 tons in 1999 is about 836 1000 tons, and it is expected to reach 980,000 tons in 2003. From 1998 to 2003, the demand growth rate of EPDM was 3.8%, which was higher than that of SBR and BR.
3, on behalf of the process characteristics
Because each company has its own patented technology in a certain part or control, it has its own unique process implementation methods, such as DSM, Exxon, uniroya 1, DuPont, Mitsui Petrochemical of Japan, JSR, etc.
The most typical one is DSM, which is not only the largest EPR producer in the world, but also four plants in the Netherlands, the United States, Japan and Brazil all adopt solution polymerization process, accounting for 1/4 of the total production capacity of EPR by solution polymerization process in the world. DSM will be taken as an example to explain.