Abstract: Thermoplastic compositions comprising a bulk polymer, an additive, and a compatibilizer/emulsifier/surfactant (CES) are described. The bulk polymer comprises an alkylene terephthalate or naphthalate polyester such as polyethylene terephthalate. The additive comprises an amorphous or substantially amorphous co-polymer of ethylene and a co-monomer that forms polar portions, such as methylacrylate, butylacrylate, ethylacrylate, or ethylhexyl methacrylate. The CES comprises a co-polymer or ter-polymer of ethylene and a glycidyl acrylate or maleic anhydride, and optionally an acrylate such as methylacrylate, ethylacrylate, propylacrylate, butylacrylate, ethylhexyl acrylate, or mixtures thereof. The thermoplastic compositions of the present invention exhibit improved molding properties, high dimensional stability, high temperature resistance, and are particularly useful in food-grade applications such as dual-ovenable containers.

Abstract: Thermoplastic compositions comprising a bulk polymer, an additive, and a compatibilizer/emulsifier/surfactant (CES) are described. The bulk polymer comprises an alkylene terephthalate or naphthalate polyester such as polyethylene terephthalate. The additive comprises an amorphous or substantially amorphous co-polymer of ethylene and a co-monomer that forms polar portions, such as methylacrylate, butylacrylate, ethylacrylate, or ethylhexyl methacrylate. The CES comprises a co-polymer or terpolymer of ethylene and a glycidyl acrylate or maleic anhydride, and optionally an acrylate such as methylacrylate, ethylacrylate, propylacrylate, butylacrylate, ethylhexyl acrylate, or mixtures thereof. The thermoplastic compositions of the present invention exhibit improved molding properties, high dimensional stability, high temperature resistance, and are particularly useful in food-grade applications such as dual-ovenable containers.

Abstract: An apparatus for thermoforming a thermoplastic article comprises an extrusion die for extruding a sheet of thermoplastic and a rotating wheel having at least one mold member. The mold member includes a male mold or forming cavity for receiving at least a portion of a substantially non-oriented (i.e., non-tensioned) thermoplastic sheet. The mold member is selectively heated and/or cooled during thermoforming to maintain the sheet in a molten or thermoformable state. The mold member also comprises a stripper plate maintained at a predetermined temperature or temperature distribution for inducing a predetermined degree of crystallinity to the sheet. The stripper plate enables the articles to be separated from the mold without distortion. In one embodiment, the thermoformed article has at least two and preferably at least three distinct regions of thermally-induced crystallinity.