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Title: Direct ink writing of tough, stretchable silicone composites
In this work, we report 3D printable soft composites that are simultaneously stretchable and tough. The matrix of the composite consists of polydimethylsiloxane containing octuple hydrogen bonding sites, resulting in a material significantly tougher than conventional polydimethylsiloxane. Short glass fibers are also added to the material. Prior to solvent evaporation, the material possesses a viscoelastic yield stress making it suitable for printing via direct ink writing. We mechanically characterize the printed composite, including fracture tests. We observe robust crack deflection and delay of catastrophic failure, leading to measured toughness values up to 2 00 000 J m −2 for specimens with 5 vol% glass fibers. The printed composites exhibit an unprecedented combination of stiffness, stretchability, and toughness.  more » « less
Award ID(s):
1720530
PAR ID:
10414972
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
Soft Matter
Volume:
18
Issue:
38
ISSN:
1744-683X
Page Range / eLocation ID:
7341 to 7347
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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