Nanostructured moulded bodies and layers and method for producing same

• US 6,291,070 B1
• Filed: 11/12/1999
• Issued: 09/18/2001
• Est. Priority Date: 05/13/1997
• Status: Expired due to Term

• Current Assignee: Leibniz-Institut für Neue Materialien gGmbH (INM)
• Original Assignee: Institut für Neue Materialien Gemeinnützige GmbH
• Inventors: Mueller, Peter, Oliveira, Peter W., Werner, Bettina, Arpac, Ertugrul, Schmidt, Helmut, Krug, Herbert, Sepeur, Stefan
• Primary Examiner(s): Boykin, Terressa M.
• Application Number:
  US09/423,840
• Time in Patent Office: 676 Days
• Field of Search: 428/412
• US Class Current: 428/412
• CPC Class Codes: B05D 7/26 synthetic lacquers or varnishes B05D7/08, B05D7/16 take precedence
• CPC Class Codes: C03C 17/007 containing a dispersed phase, e.g. particles, fibres or flakes, in a continuous phase
• CPC Class Codes: C03C 17/009 Mixtures of organic and inorganic materials, e.g. ormosils and ormocers
• CPC Class Codes: C03C 17/25 by deposition from the liquid phase
• CPC Class Codes: C03C 17/256 Coating containing TiO2
• CPC Class Codes: C03C 2217/425 consisting of a porous layer
• CPC Class Codes: C03C 2217/475 Inorganic materials
• CPC Class Codes: C03C 2218/113 by sol-gel processes
• CPC Class Codes: C04B 20/0076 characterised by the grain distribution
• CPC Class Codes: C04B 20/023 Chemical treatment
• CPC Class Codes: C04B 20/1018 with organic materials pigments or dyes C04B20/1096
• CPC Class Codes: C04B 2103/0046 added as monomers or as oligomers
• CPC Class Codes: C04B 2111/00534 for plastic surfaces, e.g. polyurethane foams
• CPC Class Codes: C04B 26/32 containing silicon
• CPC Class Codes: C04B 35/14 based on silica
• CPC Class Codes: C04B 35/486 Fine ceramics
• CPC Class Codes: C04B 35/624 Sol-gel processing
• CPC Class Codes: C04B 41/009 characterised by the material treated
• CPC Class Codes: C04B 41/49 Compounds having one or more carbon-to-metal or carbon-to-silicon linkages ; Organo-clay compounds; Organo-silicates, i.e. ortho- or polysilicic acid esters to obtain SiO2C04B41/5089, C04B41/5035; Organo-phosphorus compounds; Organo-inorganic complexes
• CPC Class Codes: C08F 283/12 on to polysiloxanes
• CPC Class Codes: C08F 292/00 : Macromolecular compounds obtained by polymerising monomers on to inorganic materials
• CPC Class Codes: C09D 4/06 : Organic non-macromolecular compounds having at least one polymerisable carbon-to-carbon unsaturated bond in combination with a macromolecular compound other than an unsaturated polymer of groups C09D159/00 - C09D187/00
• CPC Class Codes: Y10T 428/31507 : Of polycarbonate

Abstract

Described are nanostructured molded articles and layers which are produced by a wet chemical process comprising the following steps:

a) provision of a free-flowing composition containing solid nanoscaled inorganic particles having polymerizable and/or polycondensable organic surface groups;

b) introduction of said composition of step a) into a mold; or

b2) application of said composition of step a) onto a substrate; and

c) polymerization and/or polycondensation of the surface groups of said solid particles with formation of a cured molded article or a cured layer.

Claims

1. A process for producing a nanostructured moulded article or layer, comprising the following steps:

(a) providing a free-flowing composition containing solid nanoscale inorganic particles having polymerizable and/or polycondensable organic surface groups thereon;

(b1) introducing the composition of step (a) into a mould;

or

(b2) applying the composition of step (a) onto a substrate; and

(c) polymerizing and/or polycondensing the surface groups of the solid particles, thereby forming a nanostructured moulded article or layer.

2. A process of claim 1, comprising the additional step of thermally post-treating the nanostructured moulded article or layer of step (c).

3. A process of claim 2 where the step of thermally post-treating the nanostructured moulded article or layer is carried out at a temperature ranging from 60°

C. to 150°

C.

4. A process of claim 1, comprising the additional step of thermally densifying the nanostructured moulded article or layer.

5. A process of claim 4 where the step of thermally densifying the nanostructured moulded article or layer is carried out at a temperature of at least 20°

C.

6. A process of claim 5 where the step of thermally densifying the nanostructured moulded article or layer is carried out at a temperature of at least 400°

C.

7. A process of claim 1 where the solid nanoscale inorganic particles are particles of metal compounds.

8. A process of claim 7 where the solid nanoscale inorganic particles are particles of the oxides, sulfides, selenides, and tellurides of metals, and mixtures thereof.

9. A process of claim 8 where the solid nanoscale inorganic particles are particles of SiO₂, TiO₂, ZrO₂, ZnO, Ta₂O₅, SnO₂, Al₂O₃, and mixtures thereof.

10. A process of claim 1 where the polymerizable and/or polycondensable surface groups are acrylic, methacrylic, vinylic, allylic or epoxy groups.

11. A process of claim 1 where the solid nanoscale inorganic particles used in step (a) are prepared by surface modification of solid nanoscale inorganic particles using at least one compound containing a polymerizable and/or polycondensable group.

12. A process of claim 1 where the solid nanoscale inorganic particles are prepared by a sol-gel process.

13. A process of claim 1 where the solid nanoscale inorganic particles of step (a) additionally have fluorinated surface groups present thereon.

14. A process of claim 13 where the fluorinated surface groups have the formula R_f—

CH₂—

CH₂—

, wherein R_f is a perfluoroalkyl radical having 2 to 12 carbon atoms.

15. A process of claim 1 where step (c) is carried out in the presence of polymerizable and/or polycondensable monomeric or oligomeric species not bonded to said solid nanoscale inorganic particles.

16. A process of claim 1 where step (c) is carried out in the presence of a thermoinitiator and/or a photinitiator.

17. A process of claim 1 where step (c) includes a photochemical polymerization and/or polycondensation.

18. A process of claim 1 where the substrate of step (b2) is a plastic, metal, or glass substrate.

19. A nanostructured moulded article prepared by the process of claim 1.

20. A process for producing a nanostructured layer on a plastic substrate, comprising the following steps:

(a) providing a dispersion of nanoscale metal oxide particles in a system comprising at least one hydrolyzable silane containing at least one polymerizable and/or polycondensable group at a concentration of at least 15% by wt., and subsequently prehydrolyzing the at least one hydrolyzable silane;

(b) applying the composition of step (a) to a plastic substrate to form a layer; and

c) photochemically curing the layer of step (b).

21. A process of claim 20 where the nanoscale metal oxide particles are particles of Al₂O₃, TiO₂ and/or ZrO₂.

22. A process of claim 20 where the hydrolyzable silane contains an acrylic, methacrylic, vinylic, or allylic group.

23. A process of claim 20 where the concentration of the nanoscale metal oxide particles in the dispersion of step (a) is at least 20% by wt.

24. A process of claim 23 where the concentration of the nanoscale metal oxide particles in the dispersion of step (a) is at least 30% by wt.

25. A process of claim 20 where the prehydrolyzing step of step (a) is carried out in the absence of separately added organic solvent.

26. A process of claim 20 where a photoinitiator is added is added to the dispersion of step (a) before carrying out step (b).

27. A process of claim 20 where the plastic of the plastic substrate is a polyacrylate, polymethacrylate, polycarbonate, or polystyrene.

28. A plastic substrate provided with a nanostructured layer prepared by the process of claim 20.