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Title: Sustainable polyacetals from erythritol and bioaromatics
ABSTRACT

The polymerization of biorenewable molecules to polymers with hydrolyzable main‐chain functionality is one approach to identifying sustainable replacements for common, environmentally unsound packaging plastics. Bioaromatic polyacetals were synthesized via acid‐catalyzed acetal formation from dialdehydes and tetraols. Ethylene linked dialdehyde monomersVVandSSwere constructed from bioaromatics vanillin and syringaldehyde, respectively. Tetraol monomers included biogenic erythritol (E), along with pentaerythritol (P), and ditrimethylolpropane (D). Four copolymer series were prepared with varying tetraol content:E/PVV;E/DVV;E/PSS; andE/DSS. Number average molecular weights (Mn) ranged from 1,400 to 27,100 Da. Generally, the copolymerization yields were inversely proportional to the feed fraction of erythritol (E), implying that tetraolsPandDreact more readily. The materials were typically amorphous and exhibited glass transition temperatures (Tg) ranging from 57 to 159 °C, suitably mimicking theTgvalues of several commodity plastics. The syringaldehyde‐based copolymers exhibited a higherTgrange (71–159 °C) than the vanillin‐based copolymers (57–110 °C). Accelerated degradation studies in aqueous HCl (3M, 6M, concentrated) over 24 h showed that degradation (Mndecrease) was proportional to the acid concentration. A one‐year degradation study ofE50/D50‐SS(from 50% feed of erythritol) in seawater, deionized water, tap water, or pH 5 buffer showed noMndecrease; but in pH 1 buffer, the decrease was 40% (18,800 to 11,200). © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci.2016,133, 44089.

 
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NSF-PAR ID:
10236575
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Journal of Applied Polymer Science
Volume:
133
Issue:
45
ISSN:
0021-8995
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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    Acknowledgment

    This work was partially supported by the U.S. National Science Foundation (NSF) Award No. ECCS-1931088. S.L. and H.W.S. acknowledge the support from the Improvement of Measurement Standards and Technology for Mechanical Metrology (Grant No. 22011044) by KRISS.

    Figure 1

     

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