Apparatus and method for molding polyester articles having low acetaldehyde content directly from the melt formation using flash tank devoltatilization

An apparatus for producing molded thermoplastic articles comprising:

• a) means for reacting polyester precursors and forming a molten polyester homopolymer or copolymer;
• b) means for flowing the molten polyester into a mixer, without intermediate solidification of the molten polyester;
• means for injecting an acetaldehyde stripping agent into the mixer;
• said mixer being capable of forming a mixture of the molten polyester and the acetaldehyde stripping agent under superatmospheric pressure;
• c) means for flowing the mixture through one or more dies into an upper portion of a flash tank maintained under vacuum conditions therein, said dies being capable of imparting a back pressure to the mixer;
• means for removing vented gases, vapors and acetaldehyde from the flash tank;
• and
• d) means for removing collected devolatilized polyester from the flash tank and injecting the devolatilized polyester into a molding apparatus.