公开(公告)号：US5089193A

公开(公告)日：1992-02-18

申请号：US541379

申请日：1990-06-21

Applicant: Friedrich-Otto Behrens ,  Ulrich Prossler

Inventor： Friedrich-Otto Behrens ,  Ulrich Prossler

IPC: B29C47/00 ,  B29C44/34 ,  B29C47/08 ,  B29C47/64 ,  B29K23/00 ,  B29K25/00 ,  B29K105/04

CPC classification number: B29C44/3442 ,  B29C44/3446 ,  B29C47/6018 ,  B29C47/6062 ,  Y10S264/05

Abstract: A method of extruding a foamed thermoplastic plastics material wherein the plastics material and a pore regulating agent are fed into an extruder and are fused in a fusion zone. The pressure of the fused material is augmented in a further zone and the material is then caused to flow past or through an obstruction so as to be converted into the form of thin layers or strands. Thereafter, steam and a propellant are sequentially injected into the fused mixture in injection zones. The steam is either saturated or superheated and has a temperature not lower than that of the mixture. The pressure of the mixture upstream of the obstruction is higher than the vapor pressure of the steam downstream of the obstruction. The pressure of the fused mixture and steam, while the propellant is being injected, is greater than the condensation pressure of the steam. The mixture is then cooled and discharged in a still further zone whereupon it foams.

Abstract translation: 一种挤出发泡热塑性塑料材料的方法，其中将塑料材料和孔调节剂进料到挤出机中并熔融在熔融区中。 熔融材料的压力在另一区域中增加，然后使材料流过或穿过障碍物，以便转化成薄层或股线的形式。 此后，将蒸汽和推进剂依次注入注射区域中的熔融混合物中。 蒸汽饱和或过热，温度不低于混合物的温度。 障碍物上游混合物的压力高于阻塞下游蒸汽的蒸气压。 当注入推进剂时，熔融混合物和蒸汽的压力大于蒸汽的冷凝压力。 然后将混合物冷却并排放在另一区域，随后将其发泡。