Adhesion of chlorinated polyolefin (CPO) and topcoat on various types of thermoplastic polyolefins (TPO) at three different baking temperatures, 180 ºF (82 ºC), 200 ºF (93 ºC), and 220 ºF (104 ºC), was investigated using a gasoline soak test. The results showed that co-monomer in the TPO and the base used in the topcoat were critical factors in adhesion. Also, a chemical mechanism for adhesion at the interface of topcoat-CPO and CPO-TPO was proposed. Results of preliminary study on chlorinated model compounds are also reported.
