The present invention relates to a combination screw for a twin-screw extruder and a process for producing low-odor polyolefins. It comprises a barrel and a screw located within the barrel. The rear end of the barrel is provided with a main feed inlet. A vacuum vent is located near the front end of the barrel. A natural vent is positioned behind the vacuum vent on the barrel. The screw features a backflow element positioned behind the vacuum venting port and a kneading element B positioned behind the natural venting port. Multiple consecutive kneading elements A and multiple consecutive conveying elements are arranged sequentially from front to rear on the screw between the backflow element and kneading element B. This composite screw design is simple and practical. By arranging screw elements, it reduces product odor and volatile content while extending melt venting time without melt leakage from vents due to backpressure or flow resistance. It enhances venting efficiency without requiring additional vents or equipment, minimizing costs.
Country Code: CN
Application Number: CN202111418831.7
