Domestic and foreign PE new products

The research and development of foreign polyethylene new products are as follows:

Bimodal PE pipe material

Bimodal polyethylene refers to a bimodal polyethylene resin whose molecular weight distribution curve can solve the contradiction between the processability and mechanical properties of polyethylene resin, the balance between rigidity and toughness of the material, and good stress resistance. The cracking performance has a good application prospect in the fields of thin films and pipes.

At present, the main methods for producing bimodal distributed polyethylene resins are: (a) melt blending; and (b) staged reactor. The method of using two reactors in series is a method that has been industrialized so far. Low molecular weight polyethylene is obtained from the preceding reactor and high molecular weight polyethylene is obtained from the subsequent reactor. In 1963, DuPont first developed a method for producing bimodal resins by staged reaction. Unipol II developed by UCC Corporation and Borstar bimodal polyethylene production process developed by Borealis Company adopt this method. (c) Single-reactor method using a bimetallic catalyst or mixed catalyst. The single-reactor method is to synthesize a wide range of molecular weight or bimodal molecular weight distribution of polyethylene resin in a single reactor by developing a catalyst system with multiple active sites.

In 1993, BP used metallocene and ZN mixed catalysts in its fluidized bed process to produce ultra-tough, high-strength bimodal LLDPE resins. In 1994, it developed bimodal PE film resins.

In 1995, Hoechst developed the bimodal PE resin, Hostalen CM5010T3 and Hostealen CRP100, using a staged reaction method, and the performance reached the requirements for PE100 pipe materials.

In 1995, Borealis's 200,000-ton/year plant dedicated to the production of bimodal PE was completed and put into production.

In addition, Exxon also produces high-intensity bimodal LLDPEs using a mixed system of two or more metallocene catalysts. The produced GM9255F2, GM9255HS, and GM9255HP are bimodal HMWHDPEs.

In 2000, Northern Europe Chemical Company transferred Beixing bimodal polyethylene technology to Shanghai Petrochemical Co., Ltd., and in 2002 produced bimodal PE80 and PE100 tube materials YGH051T and YGH041T.

China's Yangzi Petrochemical Co., Ltd. and Beijing Yanshan Petrochemical Co., Ltd. also mastered the technology of producing two-peak HDPE with two reactors in series in the slurry process, among which Beijing Yanshan Petrochemical Company's 6380 reached PE80 pipe material. Claim.

Metallocene PE (MPE)

Since the discovery of metallocene catalysts in 1980, Kminsky received widespread attention due to its single-site and unique monomer stereoselectivity. In 1991, Exxon first started industrial production of mPE. In 2000, global metallocene and other single-site catalysts were produced. The demand for polyolefins is about 1.05 million tons. In 2002, it exceeded 1.23 million tons, 65% of which was Mlldpe. Therefore, many petrochemical companies around the world are vigorously developing their own mPE products.

Exxon's mPE product name is Exact, the initial production of mLDPE processing is not good, then the production of terpolymer mPE improved processing, can be used to blow film, medical Exact resin has good transparency and flexibility, Compared with ordinary LLDPE, the produced mLLDPE has uniform vertical and horizontal strength and good puncture resistance, and can be used to produce heavy-duty bags and food bags. Exxon launched a new mLLDPE production line. The new brand has better sealing, transparency, and toughness. It has a good application in stretch film, heavy bags and other products.

Dow Chemical Company's mPE brand name is Affinity, density from 0.895 to 0.935g/cm3, low melting point, good transparency, is mainly used for extrusion film, the newly introduced Affinty DPT1700 as a coating material is still good at 200 °C Viscosity and strength, good puncture resistance, thickness can be reduced to 0.005mm.

Japan's Mitsui Oil & Chemical Company's brand name is Umerit's mPE product, which is soft and has a low melting point. It can be used for cast film, heat seal layer of composite film or blow heavy bag.

The mHDPE Marlex D449 from Chevron Phillips offers good clarity, haze of only 6%, good blocking resistance, and processing under LLDPE processing conditions. The metallocene MDPE product Finacene ER-2245 produced by Atofina can be used for the manufacture of shrink film, food bags and other packaging products.

Other PE new products

Fina, Belgium, has introduced the WR201B and WR201BN HDPE materials for automotive fuel tanks, which can improve the safety of the fuel tank system and reduce the total production cost, and has already been tested in large-scale automobile production plants. Dow Chemicals and DSM use octene as a comonomer to develop a low density PE product (VLDPE) with a density of 0.902-0.915g/cc using a solution polymerization process. This product has good flexibility and heat sealing. It can replace EVA resin with VA content of 4%-12% for food and pharmaceutical packaging.