Interlayers comprising modified fumed silica

• US 7,867,618 B2
• Filed: 01/28/2008
• Issued: 01/11/2011
• Est. Priority Date: 06/10/2006
• Status: Active Grant

• Current Assignee: Solutia Incorporated (Eastman Chemical Company)
• Original Assignee: Solutia Incorporated (Eastman Chemical Company)
• Inventors: Yuan, Ping
• Primary Examiner(s): NAKARANI, DHIRAJLAL S
• Application Number:
  US12/021,293
• Publication Number:
  US 20080124540A1
• Time in Patent Office: 1,079 Days
• Field of Search: 428/425.6, 428/430, 428/436, 428/437, 428/441, 428/442, 428/331, 156/106, 524/492, 524/493
• US Class Current: 428/437
• CPC Class Codes: B32B 17/10018 comprising only one glass sheet
• CPC Class Codes: B32B 17/10036 comprising two outer glass sheets
• CPC Class Codes: B32B 17/10688 Adjustment of the adherence to the glass layers
• CPC Class Codes: B32B 17/10761 containing vinyl acetal
• CPC Class Codes: C01P 2004/61 Micrometer sized, i.e. from 1-100 micrometer
• CPC Class Codes: C01P 2004/62 Submicrometer sized, i.e. from 0.1-1 micrometer
• CPC Class Codes: C01P 2006/33 Phase transition temperatures
• CPC Class Codes: C01P 2006/80 Compositional purity
• CPC Class Codes: C09C 1/3081 Treatment with organo-silicon compounds
• CPC Class Codes: Y10T 428/259 Silicic material
• CPC Class Codes: Y10T 428/31601 Quartz or glass
• CPC Class Codes: Y10T 428/31616 Next to polyester [e.g., alkyd]
• CPC Class Codes: Y10T 428/31627 Next to aldehyde or ketone condensation product
• CPC Class Codes: Y10T 428/3163 Next to acetal of polymerized unsaturated alcohol [e.g., formal butyral, etc.]
• CPC Class Codes: Y10T 428/31645 Next to addition polymer from unsaturated monomers
• CPC Class Codes: Y10T 428/31649 Ester, halide or nitrile of addition polymer

Abstract

The present invention includes polymer interlayers that are used in multiple layer glazing panels. Interlayers of the present invention comprise a thermoplastic polymer, a plasticizer, and a fumed silica that has been modified to impart hydrophobic character. Interlayers incorporating such components have improved tensile modulus, moisture resistance, creep performance, anticorrosion effect, glass adhesion, and are well suited to a variety of applications, including, but not limited to, acoustic applications.

Claims

1. An interlayer, comprising:

a polymer sheet comprising poly(vinyl butyral)and 0.1 to 10 phr by weight fumed silica, wherein said fumed silica is alkylated, said polymer sheet has a glass transition temperature of less than 40°

C., and wherein said interlayer is adapted for use as layer in a multiple layer glazing and does not comprise additional polymer sheets.

2. The interlayer of claim 1, wherein said fumed silica has a carbon content of at least 0.5 weight percent.

3. The interlayer of claim 1, wherein said fumed silica is methylated.

4. The interlayer of claim 1, wherein said fumed silica has an average aggregate length of 0.15 to 0.35 microns.

5. The interlayer of claim 1, wherein said fumed silica has an average aggregate length of 0.2 to 0.3 microns.

6. The interlayer of claim 1, wherein said polymer sheet has 10 to 70 parts per hundred resin of plasticizer and 0.05 to 15 parts per hundred resin of said fumed silica.

7. The interlayer of claim 1, wherein said polymer sheet has 20 to 60 parts per hundred resin of plasticizer and 0.1 to 10 parts per hundred resin of said fumed silica.

8. The interlayer of claim 1, wherein said polymer sheet has 1.2 to 2.0 weight percent of said fumed silica.

9. The interlayer of claim 1, wherein said polymer sheet has a glass transition temperature of less than 35°

C.

10. The interlayer of claim 1, wherein said polymer sheet has a glass transition temperature of less than 30°

C.

11. A multiple layer glass panel comprising an interlayer, wherein said interlayer comprises:

a polymer sheet comprising poly(vinyl butyral) and 0.1 to 10 phr by weight fumed silica, wherein said fumed silica is alkylated, said polymer sheet has a glass transition temperature of less than 40°

C., and wherein said interlayer does not comprise additional polymer sheets.

12. The panel of claim 11, wherein said fumed silica has a carbon content of at least 0.5 weight percent.

13. The panel of claim 11, wherein said fumed silica is methylated.

14. The panel of claim 11, wherein said fumed silica has an average aggregate length of 0.15 to 0.35 microns.

15. The panel of claim 11, wherein said fumed silica has an average aggregate length of 0.2 to 0.3 microns.

16. The panel of claim 11, wherein said polymer sheet has 10 to 70 parts per hundred resin of plasticizer and 0.05 to 15 parts per hundred resin of said fumed silica.

17. The panel of claim 11, wherein said polymer sheet has 20 to 60 parts per hundred resin of plasticizer and 0.1 to 10 parts per hundred resin of said fumed silica.

18. A method of forming a multiple layer glazing, comprising:

providing a polymer sheet comprising poly(vinyl butyral) and 0.1 to 10 phr by weight fumed silica, wherein said fumed silica is alkylated, said polymer sheet has a glass transition temperature of less than 40°

C.; and

,

laminating said polymer sheet between two panes of glass to form said glazing.