Open AccessChemical Recycling of End‐of‐Life Poly(lactide) via Zinc‐Catalyzed Depolymerization and Polymerization
Author(s) -
Cheung Even,
Alberti Christoph,
Enthaler Stephan
Publication year - 2020
Publication title -
chemistryopen
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.644
H-Index - 29
ISSN - 2191-1363
DOI - 10.1002/open.202000243
Subject(s) - depolymerization , lactide , zinc , catalysis , polymerization , polymer chemistry , chemistry , monomer , ring opening polymerization , methanol , reagent , organic chemistry , polymer
The chemical recycling of poly(lactide) was investigated based on depolymerization and polymerization processes. Using methanol as depolymerization reagent and zinc salts as catalyst, poly(lactide) was depolymerized to methyl lactate applying microwave heating. An excellent performance was observed for zinc(II) acetate with turnover frequencies of up to 45000 h −1 . In a second step the monomer methyl lactate was converted to (pre)poly(lactide) in the presence of catalytic amounts of zinc salts. Here zinc(II) triflate revealed excellent performance for the polymerization process (yield: 91 %, M n ∼8970 g/mol). Moreover, the (pre)poly(lactide) was depolymerized to lactide, the industrial relevant molecule for accessing high molecular weight poly(lactide), using zinc(II) acetate as catalyst.