Synthesis and Evaluation of Urethane Polymers from PET Waste

Mahir A. Jalal

Basrah University, Polymer Research Center, Department of Chemistry and Polymer Technology, Basrah, Iraq

This study is engaged in synthesis of novel monomer bis(2-hydroxyethyl) by chemical
recycling of PET waste using excess of thioglycol in prescience of (0.5%) zinc acetate
as catalyst. Best yield of monomer was obtained (40%) when using 1:6 PET to
thioglygol molar ratio and 16 hours reaction time. The thiolyzed products were purified
and characterized by FTIR,
1H NMR and CHNS analysis and these characterizations
were proved that nucleophilic attack to carbonyl groups of PET backbone was achieved
by thiol groups instead of hydroxyl groups of thioglycol. Also, urethane polymers were
prepared by reaction of various weight ratios of bis(2-hydroxyethyl) thioterephthalatepoly(ethylene glycol) mixtures with 2,4-toluene diisocyanate monomer. Good
mechanical compression of polyurethane polymers were obtained and evaluated showing
transition properties from rigid to flexible urethane polymers.

Key Words: Chemical recycling, Depolymerization, Thiolysis, PET waste, Thioglycol, 2-mercaptoethanol, Polyurethane


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