Method and apparatus for producing a foam from a molten thermoplastic material

摘要

A method and apparatus for creating molten thermoplastic material foam by separately pressurizing the molten thermoplastic material and a gas and by delivering that material and gas sequentially to a premixing chamber, through a sintered metal insert and a post mixing chamber, to a discharge orifice of a spray nozzle. The apparatus for practicing this method comprises a nozzle assembly, including a nozzle adaptor and a nozzle, the adaptor of which has flow passages for delivering the pressurized gas and molten material to a premixing cavity and subsequently to and through a sintered metal insert contained within the nozzle.