the invention is a process for the preparation of article comprising placing a film on each inner surface of each part of a two part mold ; placing an article in the mold with film located between the surface of the mold and the article such that there is a small space between the article and the surface of the mold ; closing the mold about the article ; injecting between the film and the article an expandable plastic material under conditions that the article is coated with the expandable material and the expandable material does not expand ; removing the plastic article with the expandable material coated thereon with the two films attached to the expandable plastic material . in another embodiment the invention is an article comprising a shaped plastic article ; an expandable material coated in the shaped plastic article ; and a film covering the material coated shaped plastic article . in another embodiment the invention is a method of reinforcing a structural member which comprises inserting an article according to this invention into a cavity of the structural member and heating the structural member and the article to a temperature at which the expandable plastic material expands and the film or the expandable material bonds to the inner surface of the structural member so as to fix the location of the article in the structural member .