All Plastic products especially those soft plastic cannot stop these changes since all soft plastic are artificial synthesis (人工的合成) and must carry out deterioration(退化). Something like artificial sponge's that will become a mess of sticky substance. So almost all new cameras products use ABS resin or silicon for their coatings to prevent this problem raise.

Also, films and cassettes are made from cellulose and not the plastic, so no matter you put the film inside the camera or not. This is the problem of the soft plastic itself .