For plastics and acrylics, we recommend preparing the surface by cleaning with IPA and then performing a corona treatment prior to applying Gentoo. Corona treatment is not a requirement but is a recommendation that may help achieve the best bonding of the Gentoo coating to the substrate. Flame treatment of polyethylene plastic has also proven effective. Some plastics have not required any pre-treatment, so testing the need for pre-treatment on a specific plastic would be advised.  Some plastics may also benefit from being scuffed (and then cleaned with IPA) if this is acceptable to the customer.  Please contact us for more information