NEW YORK - In a pre-emptive public relations strike, Exxon Chemical Co. of Houston announced April 18 it is installing 1 billion pounds of production capacity that will use metallocene catalyst technology to make new polyethylene resins. Exxon's announcement came a week before Mobil Chemical Co. of Fairfax, Va., was expected to deliver a paper claiming to be the first resin supplier to use metallocene catalysts in a gas-phase PE reactor. Mobil's paper is to be delivered at the Metallocenes '95 conference in Brussels, Belgium, April 26.
At a news conference in New York, Douglas M. Selman, vice president for polymers technology for Exxon, said his company is retrofitting a gas-phase PE reactor at its Mont Belvieu, Texas, plastics plant to incorporate metallocene catalysts that will produce new, linear low density PE resins.
Those products will be introduced in the second half of this year, Irwin L. Levowitz, vice president for PE for Exxon, said. Exxon believes they will be the first large-volume LLDPE resins made with metallocene catalyst technology.
Selman also announced that Exxon received a broad patent April 11 related to using its metallocene catalysts in gas-phase reactors.
Further, Selman noted that Exxon plans to use its patented super-condensing mode technologies with its metallocene catalyst technology and its conventional, gas-phase PE production to maintain its total production capacity for LLDPE.
Meanwhile, Mobil indicated in a press release March 28 it is planning to retrofit a gas-phase reactor at its plant in Beaumont, Texas, with metallocene catalysts. A company spokesman declined to provide more details about production capacity and the time period in which the reactor will be retrofitted.
Mobil claimed to be the first resin supplier to use metallocene catalysts in a gas-phase reactor - the most common commercial reactor used to make LLDPE - but Exxon's announcement and the details Exxon supplied appear to supplant that claim.
While they said their company will have the capacity to produce 1 billion pounds of LLDPE based on metallocene catalyst technology by the end of this year, the Exxon executives did not say they actually expect to produce that amount.
Actual production will depend on demand, according to Gregory L. McPike, vice president for Exxpol Venture - the business unit Exxon set up to manage its metallocene catalyst technologies.
Levowitz said the products Exxon expects to introduce this year will be competitively priced with conventional LLDPE grades. He said Exxon has produced a variety of film grades, including clear grades, that can be processed on conventional equipment with few changes.
Exxon executives avoided saying their new products would be ``drop-in'' replacements for conventional grades of LLDPE.
They said the new products have higher melt temperatures - 10§-20§ F more than conventional LLDPE - and process with higher back pressure and higher torque load on extrusion equipment.
Levowitz would not reveal exact line speeds and gauge thicknesses produced in tests for the new resins, but he noted that Exxon has seen a 5-10 percent reduction in gauges compared with conventional LLDPE with high alpha olefin copolymers, and a 15 percent reduction in gauges compared with other conventional LLDPE resins.
Selman also said Exxon's new products will include LLDPE resins that incorporate high alpha olefin copolymers. Those copolymers - based on hexene and octene - give PE better performance characteristics.
Incorporating high alpha olefin copolymers typically diminishes reactor output, making those PE resins more expensive.
However, Selman said reactors equipped with metallocene catalysts do not have a similar drop in capacity, so the high-alpha-olefin PE made in them is not more expensive.
Levowitz said Exxon will market the new products for applications that now use conventional Exxon resins. But he said Exxon expects the new products to help increase the size of the market for LLDPE.