Yea PVC is polyvinyl chloride. It's an organic compound composed of repeating units (monomers).
poly=many
vinyl chloride=structure of the monomer (if you take organic chemistry, you will know what vinyl chloride would look like) Anyway, they take these masses of monomers, and 'stick' them together into very long chains, hence polymers. These polymers (all plastics are polymers) are very long chains and the links are bonded to each other very well. when you have a lot of these chains, they will interact (intertwine, wrapping around each other, crossing over, etc) thus being (generally) solid at room temperature (in the case of plastics).
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