Dow Chemical Co. has formed a joint partner with Japanese company Mitsui & Co. to build a plant in Brazil that makes packaging products and polymers from sugar cane-based ethanol, according to the Associated Press. The companies did not disclose financial terms of the venture but said they plan to start building by the third quarter of this year. That would accelerate Dow''s plans to make a wide variety of chemical products and plastics from renewable fuels like ethanol. The company currently makes such products from fossil fuels like refined oil, which is getting increasingly expensive. Brazil is one of the biggest and cheapest sources of ethanol because of its large sugar crop. The companies said the operation will be run by a new joint venture that will give Mitsui & Co. a 50 percent ownership stake in Dow''s Brazilian sugar cane growing operation. Dow has operated in Brazil for more than 50 years. The joint venture will initially make sugar cane-derived ethanol for use as a fuel. The company will complete a fully integrated plant that produces ethanol and bioplymer products, such as packaging for medical supplies. The joint venture should be completed by the end of 2011 pending regulatory approval.