Claims
- 1. A polymerization process, comprising:
polymerizing one or more first free radically polymerizable (co)monomers in the presence of an initiation system comprising:
a functional particle initiator comprising:
a nanoparticle; and a group comprising a radically transferable atom or group; and a catalyst comprising a transition metal complex which participates in a reversible redox cycle with at least one of the group and a compound having a radically transferable atom or group, to form a nanocomposite particle with a tethered polymer chain; polymerizing one or more second radically polymerizable comonomers on the tethered polymer chain to form an tethered copolymer chain.
- 2. The polymerization process of claim 1, wherein the nanocomposite particle comprises the nanoparticle and a tethered copolymer.
- 3. The polymerization process of claim 1, wherein the nanoparticle comprises silicon.
- 4. The polymerization process of claim 1, comprising a plurality of nanoparticles, wherein the nanoparticles have a narrow particle size distribution.
- 5. The process of claim 1, further comprising isolating a nanocomposite material comprising the nanoparticle and the tethered copolymer chain.
- 6. The process of claim 1, wherein the functional particle further comprises a functional group including the radically transferable atom or group.
- 7. The process of claim 1, wherein at least one of the first free radically polymerizable monomer(s) and the second radically polymerizable comonomer(s) comprise a functional group.
- 8. The process of claim 7, wherein the functional group comprises at least one of a hydrophilic group, a hydrophobic group, chain extension group and a crosslinking group.
- 9. The process of claim 1, wherein the nanocomposite particle comprises second functional groups responsive to external stimuli.
- 10. The process of claim 9, wherein the second functional group comprises a chromophore.
- 11. The process of claim 5, wherein the nanoparticles comprise silica or silicate particles.
- 12. The process of claim 11, wherein the silicate particles are polysilsesquioxane particles.
- 13. The process of claim 1, the ratio of the catalyst to the radically transferable atoms or groups is greater than 1.
- 14. A process for the preparation of a functional particle comprising:
providing a polysilsesquioxane particle comprising reactive groups on the surface; and reacting a silane comprising a first functional group and a second functional group comprising an alkoxy group with the polysilsesquioxane particle, wherein the first functional group comprises a polymerization initiation site.
- 15. The process of claim 14, wherein the initiation site comprises a radically transferable atom or group.
- 16. The process of claim 14, comprising a plurality of polysilsesquioxane particles having a narrow particle size distribution.
- 17. The process of claim 14, further comprising reacting at least a portion of the reactive groups on the surface with a second silane.
- 18. The process of claim 17, wherein the silane comprising the polymerization site and second silane are reacted sequentially to the polysilsesquioxane particle.
- 19. The process of claim 10, wherein the number of reactive groups is greater than 100.
- 20. A process for the preparation of a functional particle, comprising:
preparing a silica particle in a first solvent; adding a second solvent; separating the first solvent from the silica particle; and reacting a silane comprising a initiating functional group to the silica particle.
- 21. The process of claim 20, further comprising:
isolating the functional particle.
- 22. The process of claim 20, wherein the second solvent is a high boiling solvent.
- 23. The process of claim 22, wherein separating the silica particle from the first solvent comprises a distillation process.
- 24. The process of claim 23, wherein the first solvent is an alcohol or water.
- 25. The process of claim 20, further comprising:
contacting a second silane with the functional particle to react with any remaining residual silanol groups.
- 26. The process of claim 14, wherein the particles have diameters between 5 and 200 mm.
- 27. The process of claim 14, wherein the particles have diameters between 10 and 50 mm.
- 28. The process of claim 14, further comprising:
preparing the polysilsesquioxane particle in a microemulsion process.
- 29. The process of claim 28, further comprising adding a third solvent to the functional particle.
- 30. The process of claim 29, wherein the third solvent is a polar solvent.
- 31. The process of claim 30, wherein the third solvent is tetrahydrofuran.
- 32. The process of claim 20, further comprising surface treating the silica particle with one or more surface treating agents.
- 33. The process of claim 32, wherein the surface treating comprises a first coating treatment partially coating the particle and a second coating treatment comprising a coating agent with a functional group.
- 34. The process of claim 33, wherein the functional group is a group that can either respond to external stimulation or initiate a radical polymerization process or both.
- 35. The process of claim 34, wherein the particles are narrow particle size distribution particles.
- 36. The process of claim 35, wherein the particles have diameters between 5 and 200 nm.
- 37. The process of claim 36, wherein the particles have diameters between 10 and 50 nm.
- 38. The process of claim 33, wherein the ratio of coating agents in the first coating treatment to coating agents in the second coating treatment determines the number of functional groups capable of initiating polymerization on the particle surface and wherein the average number of functional groups on the particle surface is between 1 and 1 million.
- 39. The process of claim 20, wherein the average number of functional groups on the particle surfaces is between 100 and 100,000.
- 40. The process of claim 38, wherein the average number of functional groups that can initiate a radical polymerization process is between 300 and 30000.
- 41. A process for the preparation of a nanocomposite structure, comprising:
providing a material comprising a nanocomposite particle comprising silicon and a tethered polymer, wherein the tethered polymer comprises free radically (co)polymerizable monomer units; and casting, depositing or forming the material comprising the nanocomposite particle into the nanocomposite structure.
- 42. The process of claim 41, wherein the nanocomposite structure is a film, fiber or article.
- 43. The process of claim 41, wherein the tethered polymer is a block copolymer.
- 44. The process of claim 43, wherein the tethered block copolymer comprises terminal functionality and the process further comprises:
reacting the terminal functionality to chain extend the copolymer forming a network of nanocomposite particles, wherein the periodicity of the nanocomposite particles in the network is dependent on the size of the silicon based particle and the molar mass of the attached polymer chains.
- 45. The process of claim 41, wherein the nanocomposite particle comprises a particle selected from the group consisting of polysilsesquioxane or a silica with a tethered block copolymer chains.
- 46. The process of claim 34, wherein the nanocomposite particle further comprises external stimuli responsive functionality.
- 47. A process for the preparation of functional particles, comprising:
providing colloidal particles in a volatile solvent; diluting colloidal particles, wherein the colloidal particles comprise a silanol group, in a high boiling solvent; removing at least a portion of the volatile solvents; contacting the colloidal particles with a reactive silane comprising a functional group capable of initiating an atom transfer radical polymerization process; adding hexamethyldisilazane to react with any remaining residual silanol groups, thereby providing redispersable particles; and optionally, isolating the redispersable particles.
- 48. The process of claim 47, wherein the high boiling solvent is a ketone or an ether.
- 49. The process of claim 47, wherein the high boiling solvent is a dioxane.
- 50. The process of claim 20 wherein the second solvent is a dioxane.
- 51. A nanocomposite particle, comprising:
a silicon containing core and a grafted (co)polymer chain comprising two or more free radically (co)polymerizable monomers
- 52. The nanocomposite particle of claim 51, wherein the grafted (co)polymer chain comprises a block copolymer.
- 53. The nanocomposite particle of claim 52, wherein the block copolymer that can phase separate into two or more phases.
- 54. The nanocomposite particle of claim 51, wherein the grafted (co)polymer chain comprises a gradient copolymer.
- 55. A polymerization process, comprising:
polymerizing one or more first free radically polymerizable (co)monomers in the presence of an initiation system comprising:
a functional particle initiator comprising:
a nanoparticle comprising polysilsesquioxane; and a group comprising a radically transferable atom or group; and a catalyst comprising a transition metal complex which participates in a reversible redox cycle with at least one of the group and a compound having a radically transferable atom or group, to form a nanocomposite particle with a tethered polymer chain.
- 56. The polymerization process of claim 55, further comprising:
polymerizing one or more second radically polymerizable comonomers on the tethered polymer chain to form an tethered copolymer chain.
- 57. A process for preparation of a nanocomposite particle, comprising:
preparing a block copolymer comprising reactive silicon comprising segments; phase separating the block copolymer; and crosslinking the reactive silicon segments.
- 58. The process of claim 57, wherein the reactive silicon comprising segments a comprises a dialkoxylsilyl group.
- 59. The process of claim 57, wherein the phase separating is in solution or on a surface.
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is a nonprovisional application claiming priority from U.S. Application Serial No. 60/238,811.
Provisional Applications (1)
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Number |
Date |
Country |
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60238811 |
Oct 2000 |
US |