Abstract: Methods for improving the resistance of fumigant sorption in produce containers made from expandable polystyrene particles in a fumigation process, and related produce containers. An embodiment involves pre-expanding the expandable polystyrene particles to form pre-expanded particles; applying a coating comprised of a chemical selected from the group consisting of mineral oil, polyethylene wax, ethylene vinyl alcohol copolymer, and polyethylene glycol to the pre-expanded particles and in amount of 0.05 to 5.0 parts per hundred; and forming the container from the pre-expanded particles. A further embodiment involves applying the chemical coating to the expandable particles; pre-expanding the expandable polystyrene particles to form pre-expanded particles; and forming the containers from the pre-expanded particles. Other methods involve increasing the cell size of the expandable particles used to form the produce container.

Abstract: A foam thermoplastic container e.g. cup, bowl molded from expandable thermoplastic particles e.g. expandable polystyrene, has a film made of a thermoplastic resin e.g. solid polystyrene, rubber-modified polystyrene, PET, polyethylene, polypropylene, fused to its inner sidewall surface by heat and pressure to create a barrier to resist the leakage of liquid and food with oil and/or fatty components and to increase the rim strength of the container. The thermoplastic resin film can be fused to the outer surface of the container for printing purposes and/or to create a barrier and/or can be fused to the base surfaces of the container. The molding machine used to form the foam container is used to fuse the film to the container.

Abstract: Methods for improving the resistance of fumigant sorption in produce containers made from expandable polystyrene particles in a fumigation process, and related produce containers. An embodiment involves pre-expanding the expandable polystyrene particles to form pre-expanded particles; applying a coating comprised of a chemical selected from the group consisting of mineral oil, polyethylene wax, ethylene vinyl alcohol copolymer, and polyethylene glycol to the pre-expanded particles and in amount of 0.05 to 5.0 parts per hundred; and forming the container from the pre-expanded particles. A further embodiment involves applying the chemical coating to the expandable particles; pre-expanding the expandable polystyrene particles to form pre-expanded particles; and forming the containers from the pre-expanded particles. Other methods involve increasing the cell size of the expandable particles used to form the produce container.

Abstract: A foam thermoplastic container e.g. cup, bowl molded from expandable thermoplastic particles e.g. expandable polystyrene, has a film made of a thermoplastic resin e.g. solid polystyrene, rubber-modified polystyrene, PET, polyethylene, polypropylene, fused to its inner sidewall surface by heat and pressure to create a barrier to resist the leakage of liquid and food with oil and/or fatty components and to increase the rim strength of the container. The thermoplastic resin film can be fused to the outer surface of the container for printing purposes and/or to create a barrier and/or can be fused to the base surfaces of the container. The molding machine used to form the foam container is used to fuse the film to the container.