REMOVAL OF COLOR FROM THERMOPLASTICS

摘要

Process of decolorizing dyed thermoplastics are provided that includes intermixing a dyed thermoplastic with a decolorization agent solution at a temperature that maintains the crystalline structure of the thermoplastic. The processes for the first time are capable of removing substantial portions of dye from the thermoplastic providing a material that is suitable for recycling processes and use in subsequent recycled articles.

主权项

1. A process for forming a decolorized thermoplastic material comprising:
mixing a colored thermoplastic material in solid form with a decolorizing agent solution comprising one or more decolorizing agents having the structure of Formula I:
R1—[(O(CH2)m)n—]OR2   (I)where: R1 and R2 are each independently H or a C1-18 alkyl radical, benzyl radical, benzoyl radical, or phenyl radical; n is 2, 3 or 4; and m is any value from 1 to 35;
said thermoplastic material comprising one or more dyes providing color to said thermoplastic material; heating said colored thermoplastic material to a decolorization temperature that maintains the crystalline structure of said thermoplastic material, said step of heating for a decolorization time subsequent to or simultaneous with said step of mixing; and decolorizing said thermoplastic material by said mixing step, and optionally by said heating step, thereby forming a decolorized thermoplastic material.