Performance plastics are made from petrochemicals, which is a broad term for chemicals made from petroleum, fossil fuels, or sometimes renewable sources like corn or sugarcane. PVC plastic—or polyvinyl, number four on our list of chlor-alkali chemicals—is a petrochemical performance plastic.
PVC is made through a series of chemical reactions, one of which requires the chlor-alkali process. It starts with chlorine, which is reacted with ethylene. Ethylene, found in natural gas and crude oil, is what makes PVC a petrochemical.