Photocurable compositions containing reactive particles
View Patent ↗A photocurable composition, including (a) a photocurable monomer, e.g. a cationically curable monomer and/or a radically curable monomer; (b) reactive particles comprising a crosslinked elastomeric core, e.g. made of polysiloxane material, and a shell of reactive groups on an outer surface of the core, wherein the reactive groups comprise epoxy groups, ethylenically unsaturated groups, or hydroxy groups; and (c) an appropriate photoinitiator, e.g. a radical photoinitiator; and a cationic photoinitiator. A method of making a 3-D object from such a composition and a 3-D object made by the method are also provided. The cured composition generally has a smooth surface. The use of the reactive particles makes the composition more stable and the particles do not readily separate out.
1. A photocurable composition comprising:
(a) at least one photocurable monomer;
(b) reactive particles comprising a crosslinked elastomeric core and a shell of reactive groups on an outer surface of the crosslinked elastomeric core wherein the crosslinked elastomeric core comprises a crosslinked polysiloxane material and wherein the reactive groups are epoxy groups, ethylenically unsaturated groups or hydroxy groups; and
(c) at least one photoinitiator for polymerization of the photocurable monomer.
2. The photocurable composition of claim 1 wherein the photocurable monomer comprises a cationically curable monomer and the photoinitiator comprises a cationic photoinitiator.
3. The photocurable composition of claim 2 wherein the cationically curable monomer comprises a polyepoxide.
4. The photocurable composition of claim 3 wherein the polyepoxide is an alicyclic polyepoxide having a monomer purity of greater than about 94%.
5. The photocurable composition of claim 1 wherein the photocurable monomer comprises a radically curable monomer and the photoinitiator comprises a radical photoinitiator.
6. The photocurable composition of claim 5 wherein the radically curable monomer comprises a poly(meth)acrylate.
7. The photocurable composition of claim 6 wherein the poly(meth)acrylate is selected from (he group consisting of a poly(meth)acrylate having at least one hydroxy group, a mono(meth)acrylate, a di(meth)acrylate and a poly(meth)acrylate containing at least three (meth)acrylate groups.
8. The photocurable composition of claim 1 containing a cationically curable monomer, a radically curable monomer, a radical photoinitiator, and a cationic photoinitiator.
9. The photocurable composition of claim 1 wherein the crosslinked polysiloxane material comprises dialkylsiloxane repeating units.
10. The photocurable composition of claim 9 wherein the dimethylsiloxane repeating units.
11. The photocurable composition of claim 1 wherein the crosslinked elastomeric core comprises a polybutadiene material.
12. The photocurable composition of claim 1 wherein the reactive particles have an average particle diameter ranging from 0.01 μm to 50 μm.
13. The photocurable composition of claim 1 wherein the reactive particles are capable of reacting substantially completely to form chemical bonds to a polymer matrix that is formed on curing the photocurable composition.
14. The photocurable composition of claim 1 further comprising a polyether polyol.