Compression molding methods for improving the durability and weatherability of a composite material are provided. The methods include disposing a protective surface film on a composite material; adhering the protective surface film to the composite material; and compression molding the protective surface film. The composite material comprises a thermoplastic polymer and a reinforcement material. The protective surface film comprises at least one stabilizer that minimizes or prevents degradation of the underlying composite material when exposed to ultraviolet radiation and/or heat. The composite material may be heated in an oven having an environment comprising oxygen. The protective surface film may be disposed on the composite material prior to the composite material entering the oven; while the composite material is in the oven; or after the composite material exits the oven.