Injection molding system and injection molding method

An injection molding method, comprising:

• providing an extruding system configured to produce a mixture of a polymeric material and a blowing agent and having a melting unit and a mixing unit, a discharging channel communicable with the extruding system and including an outlet disposed distal to the extruding system and configured to discharge the mixture, and a first molding device including a first mold cavity and a first feeding port communicable with the first mold cavity and correspondingly engageable with the outlet, wherein the mixing unit includes a hollow mixing cartridge and a mixing rotor disposed in the hollow mixing cartridge, a length of the mixing rotor extends along a length of the hollow mixing cartridge, and a ratio of a shortest distance between an inner sidewall of the hollow mixing cartridge and the mixing rotor to a diameter of the mixing rotor is in a range of about 1:1500 to about 1:4500;
• conveying the polymeric material from the melting unit to the mixing unit;
• conveying the blowing agent into the mixing unit;
• mixing the polymeric material with the blowing agent in the hollow mixing cartridge of the mixing unit to form the mixture;
• conveying the mixture from the mixing unit to the discharging channel;
• engaging the outlet with the first feeding port;
• engaging a first element of a supporting device relative to a second element of the supporting device to secure the discharging channel with the first molding device, wherein the first element protrudes from the extruding system, and the second element is disposed on the first molding device to secure the discharging channel to the first molding device;
• discharging a first amount of the mixture from the discharging channel;
• and
• injecting the first amount of the mixture into the first mold cavity through the outlet and the first feeding port.