A healable supramolecular polymer blend based on aromatic pi-pi stacking and hydrogen-bonding interactions.
An elastomeric, healable, supramolecular polymer blend comprising a chain-folding polyimide and a telechelic polyurethane with pyrenyl end groups is compatibilized by aromatic pi-pi stacking between the pi-electron-deficient diimide groups and the pi-electron-rich pyrenyl units. This interpolymer interaction is the key to forming a tough, healable, elastomeric material. Variable-temperature FTIR analysis of the bulk material also conclusively demonstrates the presence of hydrogen bonding, which complements the pi-pi stacking interactions. Variable-temperature SAXS analysis shows that the healable polymeric blend has a nanophase-separated morphology and that the X-ray contrast between the two types of domain increases with increasing temperature, a feature that is repeatable over several heating and cooling cycles. A fractured sample of this material reproducibly regains more than 95% of the tensile modulus, 91% of the elongation to break, and 77% of the modulus of toughness of the pristine material.
Burattini
Stefano
S
Department of Chemistry, University of Reading, Whiteknights, Reading RG6 6AD, UK.
Greenland
Barnaby W
BW
Merino
Daniel Hermida
DH
Weng
Wengui
W
Seppala
Jonathan
J
Colquhoun
Howard M
HM
Hayes
Wayne
W
Mackay
Michael E
ME
Hamley
Ian W
IW
Rowan
Stuart J
SJ
D006860:Hydrogen Bonding; D007094:Imides / Q000138:chemical synthesis / Q000737:chemistry*; D046911:Macromolecular Substances / Q000138:chemical synthesis / Q000737:chemistry; D008958:Models, Molecular; D015394:Molecular Structure; D011140:Polyurethanes / Q000138:chemical synthesis / Q000737:chemistry*; D013237:Stereoisomerism
D007094:Imides; D046911:Macromolecular Substances; D011140:Polyurethanes