Title: Photochemical Transformation of Poly(butylene adipate-co-terephthalate) and Its Effects on Enzymatic Hydrolyzability

Abstract

Biodegradable polyesters are being increasingly used to replace conventional, nondegradable polymers in agricultural applications such as plastic film for mulching. For many of these applications, poly(butylene adipate-co-terephthalate) (PBAT) is a promising biodegradable material. However, PBAT is also susceptible to photochemical transformations. To better understand how photochemistry affects the biodegradability of PBAT, in this work we irradiated blown, nonstabilized, transparent PBAT films and studied their enzymatic hydrolysis, which is considered the rate-limiting step in polyester biodegradation. In parallel, we characterized the irradiated PBAT films by dynamic mechanical thermal analysis. The rate of enzymatic PBAT hydrolysis decreased when the density of light-induced cross-links within PBAT exceeded a certain threshold. Mass-spectrometric analysis of the enzymatic hydrolysis products of irradiated PBAT films provided evidence for radical-based cross-linking of two terephthalate units that resulted in the formation of benzophenone-like molecules. In a proof-of-principle experiment, we demonstrated that the addition of photostabilizers to PBAT films mitigated the negative effect of UV irradiation on the enzymatic hydrolyzability of PBAT. This work advances the understanding of light-induced changes on the enzyme-mediated hydrolysis of aliphatic-aromatic polyesters and will therefore have important implications for the development of biodegradable plastics.

Authors:

De Hoe, Guilhem X.  ^[1];

• Search DOE PAGES for author "De Hoe, Guilhem X."
• Search DOE PAGES for ORCID "0000-0002-0996-7491"

Zumstein, Michael T.  ^[2];

• Search DOE PAGES for author "Zumstein, Michael T."
• Search DOE PAGES for ORCID "0000-0002-1099-5174"

Getzinger, Gordon J.  ^[2];

• Search DOE PAGES for author "Getzinger, Gordon J."
• Search DOE PAGES for ORCID "0000-0002-5628-1425"

Rüegsegger, Isabelle ^[2]; Kohler, Hans-Peter E. ^[3]; Maurer-Jones, Melissa A. ^[2]; Sander, Michael  ^[2];

• Search DOE PAGES for author "Sander, Michael"
• Search DOE PAGES for ORCID "0000-0003-3383-2041"

Hillmyer, Marc A.  ^[1];

• Search DOE PAGES for author "Hillmyer, Marc A."
• Search DOE PAGES for ORCID "0000-0001-8255-3853"

McNeill, Kristopher  ^[2]

• Search DOE PAGES for author "McNeill, Kristopher"
• Search DOE PAGES for ORCID "0000-0002-2981-2227"

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+ Show Author Affiliations

1. Univ. of Minnesota, Minneapolis, MN (United States)
2. ETH Zurich (Switzerland). Inst. of Biogeochemistry and Pollutant Dynamics
3. Swiss Federal Inst. of Aquatic Science and Technology (Eawag), Dübendorf (Switzerland). Environmental Microbiology

Publication Date:

Wed Feb 06 00:00:00 EST 2019

Research Org.:

Argonne National Lab. (ANL), Argonne, IL (United States). Advanced Photon Source (APS)

Sponsoring Org.:

BASF SE; ETH Zurich; National Science Foundation (NSF); E.I. DuPont de Nemours & Co.; Dow Chemical Company; USDOE Office of Science (SC)

OSTI Identifier:

1504974

Grant/Contract Number:  

AC02-06CH11357

Resource Type:

Accepted Manuscript

Journal Name:

Environmental Science and Technology

Additional Journal Information:

Journal Volume: 53; Journal Issue: 5; Journal ID: ISSN 0013-936X

Publisher:

American Chemical Society (ACS)

Country of Publication:

United States

Language:

ENGLISH

Subject:

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; Organic polymers; Hydrolysis; Organic compounds; Nucleic acid structure; Irradiation