Room temperature-cured siloxane sealant compositions of reduced gas permeability

• US 20070117926A1
• Filed: 11/18/2005
• Published: 05/24/2007
• Est. Priority Date: 11/18/2005
• Status: Active Grant

• Current Assignee: Momentive Performance Materials Incorporated (Momentive Performance Materials Holdings LLC)
• Original Assignee: Momentive Performance Materials Incorporated (Momentive Performance Materials Holdings LLC)
• Inventors: Kumar, Vikram, Ramakrishnan, Indumathi, Nesakumar, Edward, Landon, Shayne, Williams, David, Shelukar, Sachin
• Granted Patent: US 7,674,857 B2
• Time in Patent Office: Days
• US Class Current: 525/106
• CPC Class Codes: C08G 77/16 to hydroxyl groups
• CPC Class Codes: C08G 77/46 containing polyether sequences
• CPC Class Codes: C08G 77/80 Siloxanes having aromatic substituents, e.g. phenyl side groups
• CPC Class Codes: C08L 2666/04 Macromolecular compounds according to groups C08L7/00 - C08L49/00, or C08L55/00 - C08L57/00; Derivatives thereof
• CPC Class Codes: C08L 2666/14 Macromolecular compounds according to C08L59/00 - C08L87/00; Derivatives thereof
• CPC Class Codes: C08L 83/04 Polysiloxanes
• CPC Class Codes: C09K 3/1018 Macromolecular compounds having one or more carbon-to-silicon linkages

Abstract

The present invention provides for a room temperature cured silicone thermoplastic resin sealant composition with reduced gas permeability useful in the manufacture of glazing such as windows and doors.

Claims

1. A curable sealant composition comprising:

(a) diorganopolysiloxane exhibiting permeability to gas;

(b) at least one polymer having a permeability to gas that is less than the permeability of diorganopolysiloxane polymer (a);

(c) cross-linker; and

,

(d) catalyst for the cross-linker reaction.

2. The sealant composition of claim 1 wherein the diorganopolysiloxane polymer, component (a), is a silanol terminated diorganopolysiloxane having the formula:

M_aD_bD′

_c

wherein a=2, b is equal to or greater than 1, c is zero or a positive integer;

M=(HO)_3-x-yR¹_xR²_ySiO_1/2;

wherein x=0, 1 or 2 and y is either 0 or 1, with the proviso that x+y is less than or equal to 2, R¹ and R² are monovalent C₁ to C60 hydrocarbon radicals;

D=R³R⁴SiO_1/2;

wherein R³ and R⁴ are monovalent C1 to C60 hydrocarbon radicals; and

D′

=R⁵R⁶SiO_2/2;

wherein R⁵ and R⁶ are independently chosen monovalent C1 to C60 hydrocarbon radicals.

3. The sealant composition of claim 1 wherein polymer (b) is selected from the group consisting of low density polyethylene (LDPE), very low density polyethylene (VLDPE), linear low density polyethylene (LLDPE), high density polyethylene (HDPE), polypropylene (PP), polyisobutylene (PIB), polyvinyl acetate(PVAc), polyvinyl alcohol (PVoH), polystyrene, polycarbonate, polyester, such as, polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polyethylene napthalate (PEN), glycol-modified polyethylene terephthalate (PETG);

polyvinylchloride (PVC), polyvinylidene chloride, polyvinylidene fluoride, thermoplastic polyurethane (TPU), acrylonitrile butadiene styrene (ABS), polymethylmethacrylate (PMMA), polyvinyl fluoride (PVF), Polyamides (nylons), polymethylpentene, polyimide (PI), polyetherimide (PEI), polether ether ketone (PEEK), polysulfone , polyether sulfone, ethylene chlorotrifluoroethylene, polytetrafluoroethylene (PTFE), cellulose acetate, cellulose acetate butyrate, plasticized polyvinyl chloride, ionomers (Surtyn), polyphenylene sulfide (PPS), styrene-maleic anhydride, modified polyphenylene oxide (PPO), ethylene-propylene rubber (EPDM), polybutadiene, polychloroprene, polyisoprene, polyurethane (TPU), styrene-butadiene-styrene (SBS), styrene-ethylene-butadiene-styrene (SEEBS), polymethylphenyl siloxane (PMPS), and mixture thereof.

4. The sealant composition of claim 3 wherein polymer (b) is selected from the group consisting of low density polyethylene (LDPE), very low density polyethylene (VLDPE), linear low density polyethylene (LLDPE), high density polyethylene (HDPE), and mixtures thereof.

5. The sealant composition of claim 4 wherein polymer (b) is selected from the group consisting of low density polyethylene (LDPE), very low density polyethylene (VLDPE), linear low density polyethylene (LLDPE), and mixture thereof.

6. The sealant composition of claim 5 wherein polymer (b) is linear low density polyethylene (LLDPE).

8. The sealant composition of claim 1 wherein the catalyst is a tin catalyst.

9. The sealant composition of claim 8 wherein the tin catalyst is selected from the group consisting of dibutyltindilaurate, dibutyltindiacetate, dibutyltindimethoxide, tinoctoate, isobutyltintriceroate, dibutyltinoxide, solubilized dibutyl tin oxide, dibutyltin bis-diisooctylphthalate, bis-tripropoxysilyl dioctyltin, dibutyltin bis-acetylacetone, silylated dibutyltin dioxide, carbomethoxyphenyl tin tris-uberate, isobutyltin triceroate, dimethyltin dibutyrate, dimethyltin di-neodecanoate, triethyltin tartarate, dibutyltin dibenzoate, tin oleate, tin naphthenate, butyltintri-2-ethylhexylhexoate, tinbutyrate, diorganotin bis β

-diketonates and mixtures thereof.

11. The sealant composition of claim 1 wherein the a diorganopolysiloxane polymer, component (a), ranges from in amount from about 50 weight percent to about 99 weight percent of the total composition.

12. The sealant composition of claim 1 wherein the a diorganopolysiloxane polymer, component (a), ranges from in amount from about 60 weight percent to about 95 weight percent of the total composition.

13. The sealant composition of claim 1, wherein the polymer, component (b), ranges from in amount from about 1 weight percent to about 50 weight percent of the total composition.

14. The sealant composition of claim 1, wherein the polymer, component (b), ranges from in amount from about 5 weight percent to about 40 weight percent of the total composition.

18. The sealant composition of claim 1 wherein the amount of the cross-linker, component (c), ranges in amount from about 0.1 weight percent to about 10 weight percent of the total composition.

19. The sealant composition of claim 1 wherein the amount of catalyst, component (d), ranges in amount from about 0.005 weight percent to about 1 weight percent of the total composition.

31. The sealant composition of claim 1 wherein the cross-linkers (c) is an alkylsilicate having the formula:

(R¹⁴O)(R¹⁵O)(R¹⁶O)(R¹⁷O)Si

where R¹⁴, R¹⁵, R¹⁶ and R¹⁷ are chosen independently from monovalent C₁ to C₆₀ hydrocarbon radicals.

7. The sealant composition of claim I containing at least one optional component selected from the group consisting of filler, adhesion promoter, non-ionic surfactant.

10. The sealant composition of claim 7 wherein the adhesion promoter is selected from the group consisting of n-2-aminoethyl-3-aminopropyltrimethoxysilane, 1,3,5-tris(trimethoxysilylpropyl)isocyanurate, γ

-aminopropyltriethoxysilane, γ

-aminopropyltrimethoxysilane, aminopropyltrimethoxysilane, bis-γ

-trimethoxysilypropyl)amine, N-Phenyl-γ

-aminopropyltrimethoxysilane, triaminofunctionaltrimethoxysilane, γ

-aminopropylmethyldiethoxysilane, γ

-aminopropylmethyldiethoxysilane, methacryloxypropyltrimethoxysilane, methylaminopropyltrimethoxysilane, γ

-glycidoxypropylethyldimethoxysilane, γ

-glycidoxypropyltrimethoxysilane, γ

-glycidoxyethyltrimethoxysilane, β

-(3,4-epoxycyclohexyl)propyltrimethoxysilane, β

-(3,4-epoxycyclohexyl) ethylmethyldimethoxysilane, isocyanatopropyltriethoxysilane, isocyanatopropylmethyldimethoxysilane, β

-cyanoethyltrimethoxysilane, γ

-acryloxypropyltrimethoxysilane, γ

-methacryloxypropylmethyldimethoxysilane, 4-amino-3,3,-dimethylbutyltrimethoxysilane, n-ethyl-3-trimethoxysilyl-2-methylpropanamine, and mixtures thereof.

15. The sealant composition of claim 7 wherein at least one filler is selected from the group consisting of clays, nano-clays, organo-clays, ground calcium carbonate, precipitated calcium carbonate, colloidal calcium carbonate, calcium carbonate treated with compounds stearate or stearic acid;

fumed silica, precipitated silica, silica gels, d hydrophobized silicas, hydrophilic silica gels, crushed quartz, ground quartz, alumina, aluminum hydroxide, titanium hydroxide, clay, kaolin, bentonite montmorillonite, diatomaceous earth, iron oxide, carbon black and graphite, talc, mica, and mixtures thereof.

16. The sealant composition of claim 7 wherein the non-ionic surfactant is selected from the group consisting of polyethylene glycol, polypropylene glycol, ethoxylated castor oil, oleic acid ethoxylate, alkylphenol ethoxylates, copolymers of ethylene oxide and propylene oxide and copolymers of silicones and polyethers, copolymers of silicones and copolymers of ethylene oxide and propylene oxide and mixtures thereof in an amount ranging from about 0.1 weight percent to about 10 weight percent.

17. The sealant composition of claim 16 wherein the non-ionic surfactant selected from the group consisting of copolymers of ethylene oxide and propylene oxide, copolymers of silicones and polyethers, copolymers of silicones and copolymers of ethylene oxide and propylene oxide and mixtures thereof.

20. The sealant composition of claim 7 wherein the amount of filler, ranges in amount from 0 to about 80 weight percent of the total composition.

21. The sealant composition of claim 7 wherein the amount of adhesion promoter ranges in amount from about 0.5 weight percent to about 20 weight percent of the total composition.

22. The sealant composition of claim 15 wherein the clay is selected from the group consisting of montmorillonite, sodium montmorillonite, calcium montmorillonite, magnesium montmorillonite, nontronite, beidellite, volkonskoite, laponite, hectorite, saponite, sauconite, magadite, kenyaite, sobockite, svindordite, stevensite, vermiculite, halloysite, aluminate oxides, hydrotalcite, illite, rectorite, tarosovite, ledikite, and kaolinite, and mixtures thereof.

23. The sealant composition of claim 22 wherein the clay is modified with an amine compounds or ammonium ion having the structure R³R⁴R⁵N, wherein R³, R⁴, and R⁵ are C₁ to C₃₀ alkyls or alkenes, and mixtures thereof.

24. The sealant composition of claim 23 wherein R³, R⁴, and R⁵ are C₁ to C₂₀ alkyls or alkenes, and mixtures thereof.

25. The sealant composition of claim 24 wherein clay is modified with a tertiary amine wherein R³is a C₁₄ to C₂₀ alkyl or alkene, and mixtures thereof.

26. The sealant composition of claim 25 wherein R⁴ and or R⁵ is a C₁₄ to C₂₀ alkyl or alkene, and mixtures thereof.

27. The sealant composition of claim 22 wherein the clay is modified with an amine or ammonium ion having the structure R⁶R⁷R⁸N, wherein at least one R⁶, R⁷, and R⁸ is C₁ to C₃₀ alkoxy silanes and the remaining are C₁ to C₃₀ alkyls or alkenes.

28. The sealant composition of claim 27 wherein at least one of R⁶, R⁷ and R⁸ is a C₁ to C₂₀ alkoxy silanes and the remaining are C₁ to C₂₀ alkyls or alkenes.

29. The sealant composition of claim 22 wherein the clay is modified with ammonium, primary alkylammonium, secondary alkylammonium, tertiary alkylammonium quaternary alkylammonium, phosphonium derivatives of aliphatic, aromatic or arylaliphatic amines, phosphines or sulfides or sulfonium derivatives of aliphatic, aromatic or arylaliphatic amines, phosphines or sulfides, and mixtures thereof.

30. The sealant composition of claim 22 wherein the clay is present in an amount from about 0.1 to about 50 weight percent of said composition.