Depolymerization of Polyesters by Transesterification with Ethanol Using (Cyclopentadienyl)titanium Trichlorides
نویسندگان
چکیده
Exclusive chemical conversions of polyesters [poly(ethylene adipate) (PEA), poly(butylene (PBA), poly(ethylene terephthalate) (PET), (PBT)] to the corresponding monomers (diethyl adipate, diethyl terephthalate, ethylene glycol, 1,4-butane diol) by transesterification with ethanol using Cp’TiCl3 (Cp’ = Cp, Cp*) catalyst have been demonstrated. The present acid-base-free depolymerizations exhibited completed (>99%) PET, PBT afford terephthalate and glycol or diol exclusively (selectivity >99%) without formation any other by-products in NMR spectra (150–170 °C, Ti 1.0, 2.0 mol%). resultant reaction mixture after depolymerization PBA via CpTiCl3 (1.0 mol%, 150 3 h), consisting adipate diol, was heated at °C vacuo for 24 h high molecular weight recycled unimodal distribution (Mn 11,800, Mw/Mn 1.6), strongly demonstrating a possibility one-pot (acid-base-free) closed-loop recycling.
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ژورنال
عنوان ژورنال: Catalysts
سال: 2023
ISSN: ['2073-4344']
DOI: https://doi.org/10.3390/catal13020421