2019
- Acquired Nakan, a global compounding solutions business
- Acquired DaVinci Roofscapes
2018
- Westlake listed as a "Fortune 500" company
- Announce expansions in chlor-alkali, PVC and VCM capacities at facilities in Germany and Louisiana
2017
- Completed 250 million pound ethylene expansion in Lake Charles, Louisiana
- Completed 100 million pound ethylene expansion in Calvert City, Kentucky
2016
- Westlake Chemical celebrates its 30th anniversary worldwide
- Westlake Chemical acquires Axiall Corporation
2015
- Acquired additional interest in Suzhou Huasu Plastics Company
- Westlake named a "Forbes Top 100 Most Trustworthy Companies in America"
2014
- Dedicates Geismar, LA Chlor-Alkali Plant
- Establishes Westlake Chemical Partners
- Acquired Vinnolit Holdings GmbH
- Announces Lake Charles Petro 1 Ethylene Expansion
- Completes Calvert City Expansions
2013
- Acquired CertainTeed's PVC Pipe, Fittings & Foundations business
- Started-up Geismar, LA Chlor-Alkali Plant
2010
- Acquired 50% ownership of Cypress Pipeline
- Commenced construction of a new chlor-alkali plant in Geismar, LA