Polyethylene terephthalate glycolysis

The effect of incorporating p-hydroxybenzoic acid (I) into the structures of various unsaturated polyesters synthesised from polyethylene terephthalate (PET) waste depolymerised by glycolysis at three different diethylene glycol (DEG) ratios with Mn acetate as transesterification catalyst, was studied. Copolyesters of PET modified using various I mole ratios showed excellent mechanical and chemical properties because of their liquid crystalline behaviour. The oligoesters obtained from the twelve modified unsaturated polyesters (MUP) were reacted with I and maleic anhydride, with variation of the I ratio with a view to determining the effect on mechanical... 

Polymer International 48,No.9, Sept. 1999, p.885-8 KINETICS OF GLYCOLYSIS OF POLYETHYLENE TEREPHTHALATE WITH ZINC CATALYST... 

Journal of Applied Polymer Science 69, No.l2, 19th Sept.1998, p.2311-9 GLYCOLYSIS OF POLYETHYLENE TEREPHTHALATE WASTES IN XYLENE Guclu G Kasgoz A Ozbudak S Ozgumus S Orbay M Istanbul,University Erzacibasi San.Ve Tic.A.S. 

The concern about possible contamination of food containers means that they can be recycled to only nonfood contact uses in the United States. To reuse polyethylene terephthalate in contact with food, it must be broken down, purified (to remove metal compounds, colors, and such), and resynthesized (14.2). This has been done by hydrolysis, methanolysis, and glycolysis.162 (The solvolysis can be complete in 4-10 min when microwaves are used with a zinc acetate catalyst.163) (For nonfood uses, such as the use of polyethylene terephthalate in magnetic tapes, it may be sufficient to melt the polymer and filter out the chromium or iron oxides.164)... 

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