Self-healing and stretchable polymeric compositions
View Patent ↗Disclosed herein a self-healing, flexible, conductive compositions. The conductive compositions include conductive polymers and acidic polyacrylamides. The compositions are useful in a wide range of applications, including wearable electronics and sensors. The compositions may be prepared using environmentally friendly procedures.
1. A flexible, self-healing, conductive composition comprising: at least one conductive polymer entangled with at least one acidic polyacrylamide, and at least one small molecule dopant comprising from 2-10 acidic groups, wherein the acidic polyacrylamide comprises a repeating unit of Formula (1):
wherein:
R 1 is selected from hydrogen and methyl;
R 2a and R 2b are independently selected from hydrogen, C 1-4 alkyl, wherein R 2a and R 2b may together from a ring;
R is in each case independently selected from H, F, Cl, C 1-4 alkyl or OCC 1-4 alkyl;
m is selected from 1, 2, 3, 4, 5, or 6; and
X is —SO 3 H, —PO 3 H, or —COOH.
2. The conductive composition according to claim 1 , wherein the weight ratio of the conductive polymer to acidic polyacrylamide is from 1:50 to 1:1.
3. The conductive composition according to claim 1 , wherein the weight ratio of the conductive polymer to small molecule dopant is from 1:20 to 1:1.
4. The conductive composition according to claim 1 , wherein the acidic polyacrylamide is a homopolymer.
5. The conductive composition according to claim 1 , wherein the acidic polyacrylamide is a copolymer.
6. The conductive composition according to claim 1 , wherein the acidic polyacrylamide has an average molecular weight from 200-2,500 kDa.
7. The conductive composition according to claim 1 , wherein for the repeating unit of Formula (1), R is in each case H, M is 1, and X is SO 3 H.
8. The conductive composition according to claim 1 , wherein for the repeating unit of Formula (1), R 2a and R 2b are each methyl and R 1 is hydrogen.
9. The conductive composition according to claim 1 , wherein the conductive polymer comprises a poly(aniline), poly(pyrrole), poly(thiophene), poly(selenophene), poly(furan), or poly(azepine).
10. The conductive composition according claim 9 , wherein the conductive polymer comprises a repeating unit of Formula (2a) or Formula (2b):
wherein R 3a , R 3b , R 3c , and R 3d are independently selected from hydrogen, C 1-6 alkyl, C 1-6 alkoxy, C 1-6 haloalkyl, C 1-6 haloalkoxy, F, Cl, Br, I, CN, and NO 2 , wherein either R 3a and R 3b or R 3c and R 3d may together form a ring; and A 1 and A 2 are independently selected from OH, SH, NHR p5 , wherein R p5 is hydrogen or C 1-10 alkyl.
11. The conductive composition according claim 1 , wherein the conductive polymer is poly(aniline).
12. The conductive composition according to claim 1 , wherein the dopant comprises a small molecule having 2-10 acidic groups, wherein the acidic groups are selected from COOH, SO 3 H, PO 3 H, and combinations thereof.
13. The conductive composition according to claim 12 , wherein the dopant comprises phytic acid, 1,3,5-cyclohexanetricarboxylic acid, 1,2,3-benzenetricarboxylic acid, or 1,2,3,4-benzenetetracarboxylic acid.
14. The conductive composition according to claim 1 , further comprising an additional conductive material, wherein the weight ratio of the additional conductive material:conductive polymer (based on the weight of the starting monomer) is from 25:1 to 1:25.
15. The conductive composition according to claim 14 , wherein the additional conductive material comprises metal nanowires.
16. The conductive composition according to claim 15 , wherein the additional conductive material comprises silver nanowires having an average diameter between 1-100 nm, and an average length from 1-100 μm.