propylene (propene), polypropylene (pp, polypropene) plastic building block

polymer plastic molecule chemical structure atoms polymerization macromolecule monomer unit repeat chain building synthetic fiber propylene propene polypropylene pp alkene polypropene thermoplastic ethylenepropylene epdm recycling atomic model molecular compound composition chemistry bond formula blackboard chalkboard chalk written writing drawing background ring line skeletal flat icon stylized style