Process for the expansion of plastics especially with a view to the manufacture of articles reduced in weight by employing carbon dioxide, and device for its use

摘要

According to this process, CO2 is dissolved in a hydrocarbon expanding agent before the mixture obtained is compressed to the value of the pressure of injection into the plastic by means: - of a dissolver mixer 10 into which are fed a hydrocarbon expanding agent via a pump 11 and a CO2 stream passing through a needle valve 12; - and of an extruder 3 in which the mixture 15 originating from the mixer 10 is fed with polymer 9. It applies to articles reduced in weight. <IMAGE>