The transaction is expected to close later this year, the companies said without disclosing financial details.
"This acquisition will expand our global PPC manufacturing footprint and allow us to better compete in the long-term growth of India's automotive market," LyondellBasell chief executive Bhavesh Patel said in a statement.
SJS, based in Maharashtra, has an annual manufacturing capacity of about 12,000 tonnes of polypropylene compounds, used in everything from car parts to home appliances.
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