Solvent-promoted self-healing materials
A composite material includes a solid polymer matrix, a plurality of capsules and a liquid, in the capsules. The liquid includes from 50 to 100 wt % of a solvent, and from 0 to 50 wt % of a polymerizer. There is no polymerizer outside of the capsules. The solid polymer matrix may include a native activating moiety for the polymerizer. The solvent may have a swelling ratio with the solid polymer matrix of at least 1.1 and/or may have a polarity ET of from 0.10 to 0.50.
1. A composite material, comprising:
a solid polymer matrix,
a plurality of capsules inside the solid polymer matrix, and
a solvent and at least 5.0 wt % of a polymerizer, in the capsules;
where there is no polymerizer outside of the capsules, and
the solvent has a swelling ratio with the solid polymer matrix of at least 1.1.
2. A method of making the composite material of claim 1 , comprising:
combining ingredients comprising the plurality of capsules and a matrix precursor, and
solidifying the matrix precursor to form the solid polymer matrix.
3. The composite material of claim 1 , where the solvent has a swelling ratio with the polymer of at least 1.2.
4. The composite material of claim 1 , where the solvent has a swelling ratio with the polymer of at least 1.5.
5. The composite material of claim 1 , where the solvent has a swelling ratio with the polymer of at least 1.9.
6. The composite material of claim 1 , where the solvent comprises a polar aprotic solvent.
7. The composite material of claim 1 , where the solvent comprises at least one solvent selected from the group consisting of chlorobenzene, phenylacetate, ethyl phenylacetate, THF, dichloromethane, nitrobenzene, NMP, DMA, DMF, DMSO, and acetonitrile.
8. The composite material of claim 1 , where the solvent comprises chlorobenzene, phenylacetate, ethyl phenylacetate, or mixtures thereof.
9. The composite material of claim 1 , where the solid polymer matrix comprises a thermoset.
10. The composite material of claim 1 , where the solid polymer matrix comprises an epoxy thermoset.
11. The composite material of claim 1 , where the capsules have an average diameter of from 10 nm to 1 mm.
12. The composite material of claim 1 , where the composite material does not comprise an exogenous activator.
13. The composite material of claim 1 , where the composite material is self-healing by the self-healing test.
14. The composite material of claim 1 , where the composite material has an average healing efficiency of at least 60% as measured by the self-healing test.
15. The composite material of claim 1 , where the composite material has an average healing efficiency of at least 70% as measured by the self-healing test.