Thread Content
HDPE and LLDPE are the main types of polyethylene; currently, China uses 1-butene as the comonomer for producing these two types of resins, as it is inexpensive and readily available in the country. However, foreign manufacturers are now tending to use 1-hexene as a comonomer; the polyethylene products produced in this way exhibit excellent properties that are difficult to match by polyethylene resins made from 1-butene. Using 1-hexene as a comonomer can significantly improve the impact and tear resistance of polyethylene, as well as enhance its toughness. Industry experts believe that the localization of hexenyl copolyethylene needs to be accelerated. Wei Zhengying, a senior engineer at the Yangzi Petrochemical Research Institute, explained that plastics are generally formed by the polymerization of two or more monomers together, and appropriate monomers are key to improving the properties of plastics. Currently, LLDPE in the United States and Europe primarily uses 1-hexene as a comonomer, while in Asia, due to differences in comonomer availability and application practices, 1-butene is still mainly used as the comonomer. From a performance perspective, it is imperative for China to accelerate the development of hexenyl copolyethylene. Most HDPE and LLDPE production facilities in China use technology introduced in the 1970s and 1980s, with 1-butene as the comonomer, resulting in a limited range of product grades. Although the later introduced units were capable of producing 1-hexene copolymer grades, due to the lack of 1-hexene resources in the country, most of them only produced such grades during the initial commissioning and acceptance tests. Based on the available public reports, 1-hexene can be used as a comonomer for the large-scale production of polyethylene (mainly HDPE) in all cases; in China, only a few companies such as Shanghai Jinfei Petrochemical Co., Ltd. are engaged in this activity. Since their introduction to the market in 1998, the company’s 23 grades of heptyl copolyethylene products across seven series have been very successful in sales; they have captured a competitive position in the high-end market for specialty materials used in various applications involving polyethylene resins. Recently, it was reported that Yanshan Petrochemical’s 1-hexene production facility has also come online, with sales of over 4,000 tons expected this year. In addition, some petrochemical companies that produce plastics have also used 1-hexene to copolymerize polyethylene, but some of the related facilities are still under construction, while others are in the stage of industrial trial production, resulting in a small amount of this material being available on the market. From the perspective of the development of plastic products, the market for hexene-based copolyethylene is far superior to that of butene-based products. It is estimated that the potential demand for hexene-based copolyethylene in the domestic market in 2010 will be around 3.7 million tons. However, it is still unclear whether this market share will be dominated by foreign products or by lower-quality products such as butene-based copolymers. Wei Zhengying believes that the market for hexenyl copolyethylene is primarily concentrated in three areas. The first is plastic material specifically designed for blow molding, which is closely related to the trend toward more functional and high-end agricultural greenhouse films. At present, the specialty materials for such films rely mainly on imports, due to insufficient production of domestically produced hexenyl copolyethylene. The second is material specifically designed for rotational molding. Currently, there are nearly a hundred rotational molding manufacturers in China, but the specialized materials required are mainly imported. Third is cable materials; developing high-quality products in this category holds good market prospects. With the rapid development of China’s plastic industry, structural overcapacity and shortages will become increasingly severe; in other words, there is a prominent imbalance with an abundance of ordinary products and a shortage of specialty grades. The development of hexenyl copolyethylene can **accelerate the development of specialty polyethylene materials in China and increase their proportion. However, 1-hexene comonomer is currently in severe shortage in China, which significantly hinders the development and production of new plastic grades and has become a bottleneck in the growth of China’s polyolefin industry. Given China’s actual conditions, it is very necessary to develop the production of 1-hexene. Currently, several manufacturers in China have made progress in the development of processes for 1-hexene, and large-scale industrial production of 1-hexene is just around the corner. Once this happens, the market situation for hexenyl copolyethylene is also expected to improve significantly.