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Title: Isocyanate- and solvent-free synthesis of melt processible polyurea elastomers derived from urea as a monomer
Polyurea elastomers are utilized for a myriad of applications ranging from coatings and foams to dielectric materials for capacitors and actuators. However, current synthetic methods for polyureas rely on highly reactive isocyanates, solvents, and catalysts, which collectively pose serious safety considerations. This report details the synthesis and characterization of melt processible, poly(tetramethylene oxide) (PTMO)-based segmented polyurea elastomers utilizing an isocyanate-, solvent-, and catalyst-free approach. Dynamic mechanical analysis and differential scanning calorimetry suggested microphase separation between the hard and soft segments. Tensile analysis revealed high strain at break for all segmented copolymers between 340 and 770%, and tunable modulus between 0.76 and 29.5 MPa. Dielectric spectroscopy revealed that the composition containing 20 wt% hard segment offered the highest permittivity at 10.6 (1 kHz, 300 K) of the segmented copolymers, indicating potential as a dielectric elastomer.  more » « less
Award ID(s):
1905597
NSF-PAR ID:
10187942
Author(s) / Creator(s):
; ; ; ; ;
Date Published:
Journal Name:
RSC Advances
Volume:
10
Issue:
32
ISSN:
2046-2069
Page Range / eLocation ID:
18760 to 18768
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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