Granted Patent B2

US 12,245,510 · App. 17/309,958 · Granted Mar 4, 2025

Inventors: Meghna Markanday (Bangalore, IN); Pradeep Singh (Bangalore, IN); Venkata Ramanarayanan Ganapathy Bhotla (Bangalore, IN); Anshita Sudarshan (Bangalore, IN)

Assignee: SABIC Global Technologies B.V.

H10N30/852C08K3/013C08K3/22C08K5/053C08L27/16H10N30/092H10N30/098C08K2003/2237

Abstract

Claims (32)

1. A piezoelectric composite comprising a piezoelectric additive, a polymeric matrix, and 3 wt. % to 30 wt. % of a polyol based on the total weight of the piezoelectric composite;

wherein the piezoelectric composite is mechanically flexible film; and

wherein the polymeric matrix comprises a polyvinylidene difluoride (PVDF) polymer.

2. The piezoelectric composite of claim 1 , wherein the polyol is glycerol, alkylene glycols or mixtures thereof.

3. The piezoelectric composite of claim 1 , wherein the polyol comprises glycerol.

4. The piezoelectric composite of claim 3 , wherein the piezoelectric composite has a piezoelectric constant (d 33 pC/N) that is greater than the piezoelectric constant of the piezoelectric composite absent the polyol.

5. The piezoelectric composite of claim 4 , wherein the d 33 of the piezoelectric composite having the polyol is greater than 55 pC/N.

6. The piezoelectric composite of claim 1 , wherein the piezoelectric composite has a dielectric constant at 100 Hz that is less than the dielectric constant of the piezoelectric composite absent the polyol at 100 Hz.

7. The piezoelectric composite of claim 6 , wherein the dielectric constant of the piezoelectric composite having the polyol is less than 100.

8. The piezoelectric composite of claim 1 , wherein the piezoelectric additive is dispersed in the polymeric matrix and the glycerol is solubilized in the polymeric matrix.

9. The piezoelectric composite of claim 1 , wherein the piezoelectric additive is a ceramic.

10. The piezoelectric composite of claim 1 , wherein the piezoelectric composite comprises 2 to 70 wt. % polymer matrix and 30 to 98 wt. % lead zirconate titanate (PZT).

11. The piezoelectric composite of claim 10 , having:

a d 33 of at least 60 pC/N; and

a dielectric constant at 100 Hz of less than 65.

12. The piezoelectric composite of claim 1 , wherein the polymeric matrix comprises a thermoplastic or thermoset polymer or blends thereof.

13. A method of producing the piezoelectric composite of claim 1 , the method comprising:

(a) obtaining a solution comprising polyol, a polymer, and optional solvent, wherein the solution includes at least 1 wt. % of the polyol based on the weight percentage of polymer;

(b) dispersing a piezoelectric additive in the solution; and

(c) subjecting the dispersion of step (b) to conditions suitable to form the piezoelectric composite.

14. The method of claim 13 , wherein step (c) conditions comprise

(i) solvent casting the dispersion on a substrate;

(ii) air/drying/heat treating the step (i) dispersion to form a composite; and

(iii) applying a poling field to the composite to form a piezoelectric composite.

15. The method of claim 13 , wherein the step (a) solution comprises 1 to 30 wt. % of polyol, and 70 wt. % to 99 wt. % polymer.

16. The method of claim 13 , wherein:

the polyol is glycerol;

the polymer is a thermoplastic polymer, a thermosetting polymer or copolymer, or a blend thereof; and/or

the piezoelectric additive is a perovskite material.

17. The method of claim 13 , wherein the composite is a film or sheet.

18. A piezoelectric device comprising any one of the piezoelectric composites of claim 1 .

19. The piezoelectric device of claim 18 , wherein the device is a piezoelectric sensor, a piezoelectric transducer, or a piezoelectric actuator.

Assignments (1)

Continuity (2)

References Cited (17)