HOUSTON (Feb.1)—ExxonMobil Chemical Co. of Houston will become the sole owner of Advanced Elastomer Systems L.P., after purchasing St. Louis-based Solutia Inc.´s 50-percent portion of the company. The two firms signed a binding contract for the acquisition subject to government review on Feb. 1, a prepared statement said. Terms of the agreement were not disclosed. ExxonMobil and Solutia formed the Akron-based AES in 1991 through a limited 50/50 partnership. The thermoplastic vulcanizate maker employs about 700 worldwide and had sales of about $300 million in 2001. Solutia announced its plan to put AES up for sale in 2000, saying the company did not fit into its strategy.