Room temperature cubable organopolysiloxane composition

• US 20070173596A1
• Filed: 01/09/2006
• Published: 07/26/2007
• Est. Priority Date: 01/09/2006
• 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, Williams, David, Ramakrishnan, Indumathi, Nesakumar, Edward, Landon, Shayne
• Granted Patent: US 7,625,976 B2
• Time in Patent Office: Days
• US Class Current: 524/588
• CPC Class Codes: C08G 77/16 to hydroxyl groups
• CPC Class Codes: C08G 77/80 Siloxanes having aromatic substituents, e.g. phenyl side groups
• CPC Class Codes: C08K 3/34 Silicon-containing compounds
• CPC Class Codes: C08K 5/5419 containing at least one Si—C bond
• CPC Class Codes: C08L 2666/54 Inorganic substances
• CPC Class Codes: C08L 83/00 Compositions of macromolecular compounds obtained by reactions forming in the main chain of the macromolecule a linkage containing silicon with or without sulfur, nitrogen, oxygen or carbon only; Compositions of derivatives of such polymers
• CPC Class Codes: C08L 83/04 Polysiloxanes
• CPC Class Codes: C09D 183/04 Polysiloxanes

Abstract

This invention relates to a room temperature curable composition containing, inter alia, diorganopolysiloxane(s) and organic nanoclay(s), the cured composition exhibiting low permeability to gas(es).

Claims

1. A curable composition comprising:

a) at least one silanol-terminated diorganopolysiloxane;

b) at least one crosslinker for the silanol-terminated diorganopolysiloxane(s);

c) at least one catalyst for the crosslinking reaction;

d) at least one organic nanoclay; and

, optionally,

e) at least one solid polymer having a permeability to gas that is less than the permeability of the crosslinked diorganopolysiloxane(s).

2. The composition of claim 1 wherein silanol-terminated diorganopolysiloxane (a) has the general formula:

M_aD_bD′

_c

wherein “

a”

is 2, and “

b”

is equal to or greater than 1 and “

c”

is zero or positive;

M is

(HO)<sub>3−

x−

y</sub>R¹_xR²_ySiO_1/2

wherein “

x”

is 0, 1 or 2 and “

y”

is either 0 or 1, subject to the limitation that x+y is less than or is equal to 2, R¹ and R² each independently is a monovalent hydrocarbon group up to 60 carbon atoms;

D is

R³R⁴SiO_1/2;

wherein R³ and R⁴ each independently is a monovalent hydrocarbon group up to 60 carbon atoms; and

D is

R⁵R⁶SiO_2/2

wherein R⁵ and R⁶ each independently is a monovalent hydrocarbon group up to 60 carbon atoms.

3. The composition of claim 1 wherein crosslinker (b) 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.

4. The composition of claim 1 wherein catalyst (c) is a tin catalyst.

5. The composition of claim 4 wherein the tin catalyst is selected from the group consisting of dibutyltindilaurate, dibutyltindiacetate, dibutyltindimethoxide, tinoctoate, isobutyltintriceroate, dibutyltinoxide, dibutyltin bis-diisooctylphthalate, bis-tripropoxysilyl dioctyltin, dibutyltin bis-acetylacetone, silylated dibutyltin dioxide, carbomethoxyphenyl tin tris-uberate, isobutyltin triceroate, dimethyltin dibutyrate, dimethyltin di-neodecanoate, triethyltin triethyltin tartarate, dibutyltin dibenzoate, tin oleate, tin naphthenate, butyltintri-2-ethylhexylhexoate, tinbutyrate, diorganotin bis β

-diketonates and mixtures thereof.

6. The composition of claim 1 wherein the nanoclay portion of organic nanoclay (d) 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, kaolinite and, mixtures thereof.

7. The composition of claim 1 wherein the organic portion of organic nanoclay (d) is at least one tertiary amine compound R³R⁴R⁵N and/or quarternary ammonium compound R⁶R⁷R⁸N⁺X⁻

wherein R³, R⁴, R⁵, R⁶, R⁷ and R⁸ each independently is an alkyl, alkenyl or alkoxy silane group of up to 60 carbon atoms and X is an anion.

8. The composition of claim 6 wherein the nanoclay portion of organic nanoclay (d) 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.

9. The composition of claim 1 wherein solid polymer (e) is selected from the group consisting of low density polyethylene, very low density polyethylene, linear low density polyethylene, high density polyethylene, polypropylene, polyisobutylene, polyvinyl acetate, polyvinyl alcohol, polystyrene, polycarbonate, polyester, such as, polyethylene terephthalate, polybutylene terephthalate, polyethylene napthalate, glycol-modified polyethylene terephthalate, polyvinylchloride, polyvinylidene chloride, polyvinylidene fluoride, thermoplastic polyurethane, acrylonitrile butadiene styrene, polymethylmethacrylate, polyvinyl fluoride, polyamides, polymethylpentene, polyimide, polyetherimide, polether ether ketone, polysulfone , polyether sulfone, ethylene chlorotrifluoroethylene, polytetrafluoroethylene, cellulose acetate, cellulose acetate butyrate, plasticized polyvinyl chloride, ionomers, polyphenylene sulfide, styrene-maleic anhydride, modified polyphenylene oxide, ethylene- propylene rubber, polybutadiene, polychloroprene, polyisoprene, polyurethane, styrene-butadiene-styrene, styrene-ethylene-butadiene-styrene, polymethylphenyl siloxane and mixtures thereof.

10. The composition of claim 1 which further comprises at least one optional component selected from the group consisting of adhesion promoter, surfactant, colorant, pigment, plasticizer, filler other than organic nanoclay, antioxidant, UV stabilizer, and biocide.

11. The composition of claim 10 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.

12. The composition of claim 10 wherein the surfactant is a nonionic surfactant 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.

13. The composition of claim 12 wherein the non-ionic surfactant is 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.

14. The composition of claim 10 wherein the filler other than the organic nanoclay is selected from the group consisting of calcium carbonate, precipitated calcium carbonate, colloidal calcium carbonate, calcium carbonate treated with compounds stearate or stearic acid, fumed silica, precipitated silica, silica gels, 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, mica, talc, and mixtures thereof.

15. The curable composition of claim 1 wherein:

silanol-terminated diorganopolysiloxane (a) has the general formula;

M_aD_bD′

_c

wherein “

a”

is 2, and “

b”

is equal to or greater than 1 and “

c”

is zero or positive;

M is

(HO)<sub>3−

x−

y</sub>R¹_xR²_ySiO_1/2

wherein “

x”

is 0, 1 or 2 and “

y”

is either 0 or 1, subject to the limitation that x+y is less than or is equal to 2, R¹ and R² each independently is a monovalent hydrocarbon group up to 60 carbon atoms;

D is

R³R⁴SiO_1/2;

wherein R³ and R⁴ each independently is a monovalent hydrocarbon group up to 60 carbon atoms; and

D′

is

R⁵R⁶SiO_2/2

wherein R⁵ and R⁶ each independently is a monovalent hydrocarbon group up to 60 carbon atoms;

crosslinker (b) is an alkylsilicate having the formula;

(R¹⁴O)(R¹⁵O)(R¹⁶O)(R¹⁷O)Si

where R¹⁴, R¹⁵, R¹⁶ and R¹⁷ are chosen independently from monovalent hydrocarbon radicals of up to 60 carbon atoms;

catalyst (c) is a tin catalyst; and

,

nanoclay portion of organic nanoclay (d) 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, kaolinite and, mixtures thereof, the organic portion of organic nanoclay (d) being at least one tertiary amine compound R³R⁴R⁵N and/or quarternary ammonium compound R⁶R⁷R⁸N⁺X⁻

wherein R³, R⁴R⁵, R⁶, R⁷ and R⁸ each independently is an alkyl, alkenyl or alkoxy silane group of up to 60 carbon atoms and X is an anion.

16. The cured composition of claim 1.

17. The cured composition of claim 9.

18. The cured composition of claim 10.

19. The cured composition of claim 15.

20. The composition of claim 16 exhibiting an argon permeability coefficient of not greater than about 900 barrers.

21. The composition of claim 17 exhibiting an argon permeability coefficient of not greater than about 900 barrers.

22. The composition of claim 18 exhibiting an argon permeability coefficient of not greater than about 900 barrers.

23. The composition of claim 19 exhibiting an argon permeability coefficient of not greater than about 900 barrers.