| 摘要 |
A method and apparatus for the production of foamed thermoplastics using nitrogen gas as the foaming agent, wherein the nitrogen gas is mixed with a polymer melt in a mixing apparatus of the type comprising a hollow cylindrical stator (14), (not necessarily static), and a cylindrical rotor (10) journalled for rotation within the stator (14), the facing cylindrical-surfaces of the rotor and stator carrying respective pluralities of circumferentially extending rows of cavities (18, 20); between which material to be mixed is passed in travelling through the mixer. Nitrogen gas is introduced into the polymer melt via a gas injector disposed at the upstream end of the mixer. <IMAGE> |
