Resumen
The present invention relates to a new material capable of self-healing without requiring external energy sources, comprising an elastomeric adhesive matrix filled with particles having strong magnetization, in other words, high magnetic coercivity. When said material is broken into two or more parts and these parts are again moved closer to one another, the magnetic particles interact with one another, healing said crack. Furthermore, this material can be doped with conductive nanoparticles such that the structure allows the self-healing of the material, as well as providing dependence between the electrical resistance and the strain of the material.
Reivindicaciones
1. A self-healable material, characterized in that it comprises • an elastomeric adhesive matrix with a service temperature stiffness comprised between 0.5 kPa and 12 kPa, considering a service temperature interval of between 5°C and 50°C; and • a plurality of magnetic particles with at least 150 mT of residual magnetization, wherein said particles are homogeneously distributed throughout the entire volume of the elastomeric adhesive matrix, have a particle size of between 5 µm and 55 µm, and wherein the volume ratio of said particles with respect to the total material is between 8% and 32%. 2. The self-healable material according to claim 1, wherein the elastomeric adhesive matrix is formed by an elastomer material selected from polysiloxane, two-phase polysiloxane, polydimethylsiloxane, polyvinyl siloxane, vinylmethylsiloxane-dimethylsiloxane copolymers, and any combination thereof. 3. The self-healable material according to claim 2, wherein the material of the elastomeric adhesive matrix is a polyvinyl siloxane. 4. The self-healable material according to any of claims 1 to 3, wherein the magnetic particles are selected from NdFeB, SmCo, BaFeO particles and any combination thereof. 5. The self-healable material according to claim 4, wherein the magnetic particles are NdFeB particles. 6. A self-healable conductive material, characterized in that it comprises • the self-healable material according to any of claims 1 to 5; and • conductive particles, wherein said particles are homogeneously distributed throughout the entire volume of the elastomeric adhesive matrix of the self-healable material, have a particle size of between 10 nm and 50nm, and wherein the volume ratio of said particles with respect to the total conductive composite material is between 8% and 15%. 7. The self-healable conductive material according to claim 6, wherein the conductive particles are selected from carbon nanoparticles of up to 300 nm, silver nanoparticles, copper nanoparticles, gold nanoparticles, and any combination thereof. 8. The self-healable conductive material according to claim 7, wherein the conductive particles are carbon nanoparticles of up to 300 nm. 9. The self-healable conductive material according to any of claims 6 to 8, wherein the volume ratio of the conductive particles with respect to the total conductive material is 10%. 10. A method for obtaining the self-healable material according to claims 1 to 5, characterized in that it comprises the following steps: a) preheating an elastomer material at a temperature of between 70°C and 80°C for at least 2 min and mixing with the magnetic particles in a particle volume ratio with respect to the total material of between 8% and 32%; b) pouring the mixture obtained in (a) in a mold and performing degasification; c) curing the degasified mixture obtained in (b) at a temperature of between 90°C and 100°C for a time of between 90 min and 24 hours; d) permanently magnetizing the material obtained in c) by means of using an impulse magnetizer and removing from the mold. 11. The method for obtaining the self-healable material according to claim 10, wherein before step a), if the elastomer material is a two-phase polysiloxane, mixing of the two components of the elastomer material in a volume ratio of between 5:6 and 6:5 is performed. 12. The method for obtaining the self-healable conductive material according to claims 6 to 9, characterized in that it comprises the following steps: i. Mixing an elastomer material with conductive particles in a particle volume ratio with respect to the total material of between 8% and 15%; ii. adding magnetic particles to the mixture obtained in (i) in a volume ratio of between 8% and 32% and mixing until homogenization; iii. removing particle aggregates from the mixture obtained in (ii) and adding into a mold; iv. degasifying the mixture in the mold obtained in (iii) for at least 20 min; v. heating the degasified mixture in the mold obtained in (iv) at a temperature of between 90 and 100°C for a time of between 90 min and 24 h; and vi. permanently magnetizing the material obtained in (v) by means of using an impulse magnetizer and removing from the mold. 13. The method according to claim 12, wherein the mixing of step (i) is first performed manually and then mechanically with a technique selected from mixing and passage into conical tipped syringe; or the mixing performed in step (i) is carried out by introducing the elastomer material with the conductive particles in a 3D printing device and performing the printing of these materials. 14. Use of the self-healable material according to any of claims 1 to 5 as a sensor-actuator in microfluidic membranes. 15. Use of the self-healable conductive material according to any of claims 6 to 9 as an end-of-travel sensor for structural components or joints of the human body. 16. A device which can be adhered to different joints of structural components or the human body itself which comprises the self-healable conductive material according to claims 6 to 9, located between two low-current electrodes, wherein the self-healable conductive material is arranged on the joint such that rotations of said joint result in the extension of the material and configured so that extensions of the self-healable conductive material and, particularly, its rupture , give rise to sudden changes in the electrical resistance thereof.
