Preparation and application of chain-extending concentrates for polyester foaming process

摘要

The composition and the preparation of a chain-extending concentrate for production of foamed cellular materials of aromatic polyesters is disclosed in this invention. The chain-extending concentrate is comprised of an ethylene-acrylate copolymer, a high-temperature thermoplastic and a multifunctional compound. The preparation process consists of two steps: 1) Mixing and melt blending the multifunctional compound and the HT thermoplastic resin into the matrix of the ethylene-acrylate copolymer in an internal mixer and 2) extrusion of the mixture at a temperature below the melting point or reaction temperature of the multifunctional compound.