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Title: Hydrolytic Degradation of 3D-Printed Poly (Lactic Acid) Structures
Hydrolytic degradation of commercially available 3D printing filament, i.e. poly (lactic acid) with broad molecular weight distribution was induced by incubating 3D-printed parts in deionized water at 3 temperatures. Small changes in orthogonal dimensions occurred due to relaxation of printing stresses, but no mass or volume loss were detected over the time-frame of the experiments. Molecular weight decreased while polydispersity remained constant. The most sensitive measure of degradation was found to be nondestructive, small-amplitude oscillatory tensile measurements. A rapid decay of tensile storage modulus was found with an exponential decay time constant of about an hour. This work demonstrates that practical monitoring of commercially available PLA degradation can be achieve with linear viscoelastic measurements of modulus.  more » « less
Award ID(s):
1804871
PAR ID:
10347581
Author(s) / Creator(s):
; ; ; ; ; ;
Date Published:
Journal Name:
Sustainable Development Research
Volume:
3
Issue:
3
ISSN:
2690-9898
Page Range / eLocation ID:
p17
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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