Modification of waste poly( ethylene terephthalate) (PET) by using poly(L-lactic acid) (PLA) and hydrolytic stability

Acar I., Kasgoz A., Ozgumus S. K., ORBAY M.

POLYMER-PLASTICS TECHNOLOGY AND ENGINEERING, cilt.45, sa.3, ss.351-359, 2006 (SCI-Expanded) identifier identifier

Özet

The purpose of this study is the preparation of hydrolytically degradable copolymers of waste poly( ethylene terephthalate) ( PET). To achieve this, we modified PET by using biodegradable poly( lactic acid) (PLA). Modification reactions were carried out in o-nitrophenol as solvent at 140 and 170 degrees C for 8, 16, and 24 h in the presence of dibutil tin oxide (DBTO) as catalyst. The amount of the total polymers ( PLA and PET) in the reaction mixture was 30% by weight, and the weight ratios of PLA/PET were 10/90, 50/50, and 90/10. These modified products were characterized by Fourier transform infrared spectrometer ( FTIR), differential scanning calorimeter (DSC) as well as by hydrolytic degradation determinations. Hydrolytic degradations of the products were determined gravimetrically. Disc-shaped samples were placed in tubes containing phosphate buffer solution of pH 7.2 and kept in a water bath at 60 degrees C for 28 days. The weight loss of the products after hydrolytic degradation ranged from 1.25% to 48.75% after 28 days.

The purpose of this study is the preparation of hydrolytically degradable copolymers of waste poly(ethylene terephthalate) (PET). To achieve this, we modified PET by using biodegradable poly(lactic acid) (PLA). Modification reactions were carried out in o-nitrophenol as solvent at 140 and 170°C for 8, 16, and 24 h in the presence of dibutil tin oxide (DBTO) as catalyst. The amount of the total polymers (PLA and PET) in the reaction mixture was 30% by weight, and the weight ratios of PLA/PET were 10/90, 50/50, and 90/10. These modified products were characterized by Fourier transform infrared spectrometer (FTIR), differential scanning calorimeter (DSC) as well as by hydrolytic degradation determinations. Hydrolytic degradations of the products were determined gravimetrically. Disc-shaped samples were placed in tubes containing phosphate buffer solution of pH 7.2 and kept in a water bath at 60°C for 28 days. The weight loss of the products after hydrolytic degradation ranged from 1.25% to 48.75% after 28 days.