| 摘要 |
PROBLEM TO BE SOLVED: To quantitatively and uniformly mix and disperse a modifier by melting and mixing thermoplastic polyester resin and a modifier for melt properties in a tandem extruder constituted of a biaxial extruder at the front stage and a monoaxial extruder at the rear stage and mixing a foaming agent, and extruding the mixture from the metal mouth to a low pressure zone. SOLUTION: A composition in which thermoplastic polyester resin and a modifier for melt properties are mixed is supplied in a tandem extruder in which a biaxial extruder of rotational meshing in the same direction, and having kneading disc parts as the first stage extruder at the upstream side at the injection opening for the foaming agent of the later half part of the cylinder, and a monoaxial extruder as the second stage extruder, are connected with each other by a conveying pipe, and further a foaming agent is injected to extrude and foam the mixture in a specified condition. That is, the foaming resin composite material melted and kneaded in the first stage biaxial extruder is transferred to the second stage monoaxial extruder. While the material is continuously melted and kneaded by the monoaxial extruder to homogenization of the resin structure and temperature is effected. The foamable resin composition is extruded from the metal mouth attached to the front end of the second stage extruder to the low pressure zone. |
