Dow Chemical is to sell its Styron unit to Bain Capital, two sources familiar with the matter said on Tuesday. Dow, the No. 1 U.S. chemicals company, put Styron up for sale in July and said at the time the unit could fetch $1 billion to $2 billion. It hopes to sell the unit, which makes polystyrene, rubber and latex, by the first quarter of 2010.

The deal is to be worth more than $1.5 billion, one of the sources said.