TPC Group shareholders approve buyout by First Reserve and SK

Shareholders of TPC Group Inc., the biggest producer of a chemical used to make synthetic rubber, approved a $705.9 million takeover bid from First Reserve Corp. and SK Capital Partners.

The $45-a-share offer was supported by 77 percent of shareholders, the company said today at a special meeting in Houston, where TPC is based. The transaction is fully financed and approved by regulators.

The vote ends a bidding war for the chemical maker that began Aug. 27 with an initial offer by SK and First Reserve of $40 a share. They raised their bid to $45 on Nov. 8 after fuel additives maker Innospec Inc. made a non-binding offer of $44 to $46. Innospec subsequently raised its offer to $47.50 a share, to be financed by Blackstone Group LP, before withdrawing the bid Dec. 3.

TPC, formerly known as Texas Petrochemical Inc., competes in the market for butadiene, an ingredient in synthetic rubber, with LyondellBasell Industries NV, Royal Dutch Shell Plc and Exxon Mobil Corp. It’s planning to boost its output by refurbishing a Houston plant to make the chemical from butane, a component of natural gas that has increased in supply with production from shale-rock formations.

Sandell Asset Management Corp., TPC’s third-largest shareholder, called the $40 bid “an outrage” and last month said management should have held an auction.