Method of stabilizing imino-functional silane

Patent metadata

Field	Value
Publication number	US-10457697-B2
Application number	US-201715649919-A
Country	US
Kind code	B2
Filing date	Jul 14, 2017
Priority date	Jul 15, 2016
Publication date	Oct 29, 2019
Grant date	Oct 29, 2019

Abstract

A method of stabilizing imino-functional silane involving adding thereto at least one Brønsted-Lowry base to inhibit, suppress or prevent the addition reactions of the imino-functional silane with itself to form a imino- and amino-functional silane and the subsequent deamination reactions to form conjugated carbon-carbon double bond-containing imino-functional silanes and stabilized imino-functional silanes containing the at least one Brønsted-Lowry base.

First claim

The invention claimed is:

1. A method of stabilizing imino-functional silane comprising:
a) adding a Brønsted-Lowry base to an imino-functional silane; and,
b) mixing the imino-functional silane with the Brønsted-Lowry base to provide stabilized imino-functional silane.

2. The method of claim 1 , wherein the imino-functional silane is an imino-functional alkoxysilane of general formula (I):

wherein:
R 0 is hydrogen, a monovalent hydrocarbon group of from 1 to about 20 carbon atoms or a monovalent heterocarbon group of from 1 to about 20 carbon atoms containing one or more heteroatoms;
R 1 is a divalent hydrocarbon group of from 1 to about 20 carbon atoms or a divalent heterocarbon group of from 1 to about 20 carbon atoms;
R 2 is an alkyl group of from 1 to about 5 carbon atoms;
R 3 is phenyl or an alkyl group of from 1 to about 8 carbon atoms;
G is a monovalent or polyvalent hydrocarbon group of from 1 to about 30 carbon atoms or a heterocarbon group of from 1 to about 30 carbon atoms containing one or more heteroatoms;
subscript a is 0, 1 or 2; and,
subscript x is 1, 2, 3 or 4.

3. The method of claim 1 , wherein the imino-functional silane is at least one member selected from the group consisting of:
aldimino-functional silane of general formula (IV):

wherein:
R 1 is a divalent hydrocarbon group of up to about 20 carbon atoms or a divalent heterocarbon group of up to about 20 carbon atoms containing one or more heteroatoms;
R 2 is an alkyl group of from 1 to about 5 carbon atoms;
R 3 is phenyl or an alkyl group of from 1 to about 8 carbon atoms;
Y 1 and Y 2 each independently is hydrogen, an organic radical or together with the carbon atom to which they are bonded form a carbocyclic or heterocyclic ring of from about 5 to about 8 ring atoms;
Y 3 is hydrogen, an unsubstituted or substituted alkyl group of up to about 10 carbon atoms containing one or more heteroatoms, an unbranched or branched alkyl or alkylenyl group of up to about 10 carbon atoms, a substituted or unsubstituted aryl or arylalkyl group of up to about 20 carbon atoms, or an —OR 4 , —OC(═O)—R 4 , —C(═O)OR 4 or —C(═O)R 4 group in which R 4 is an unsubstituted or substituted alkyl group of from 3 to about 20 carbon atoms; and,
subscript a is 0, 1 or 2,

aldimino-functional silane of general formula (VI):

wherein:
R 1 , R 2 , R 3 and subscript a have the aforestated meanings for aldimino-functional silane (IV);
R 5 and R 6 each independently is hydrogen, a monovalent hydrocarbon group of from 1 to about 12 carbon atoms or together with the carbon atom to which they are bonded form an unsubstituted or substituted ring of from about 5 to about 12 carbon atoms, or a heterocarbon group containing from 1 to about 12 carbon atoms;
R 7 is hydrogen, a monovalent hydrocarbon group of up to about 20 carbon atoms, a heterocarbon group containing up to about 20 carbon atoms and one or more heteroatoms, or an alkoxycarboxyl group of from 2 to about 20 carbon atoms; and,
R 8 and R 9 each independently is a monovalent hydrocarbon group of up to about 20 carbon atoms, a heterocarbon group containing up to about 20 carbon atoms and one or more heteroatoms, or an alkoxycarboxyl group of from 2 to about 20 carbon atoms, or R 8 and R 9 and the carbon atom to which they are bonded form an unsubstituted or substituted ring of from about 5 to about 12 carbon atoms containing zero, one or more heteroatoms,

and ketimino-functional silane of general formula (VIII):

wherein:
R 1 , R 2 , R 3 and subscript a each have one of the same meanings stated above for aldimino-functional silane (IV);
R 10 and R 11 each independently is a monovalent hydrocarbon group of up to about 20 carbon atoms or a monovalent heterocarbon group of up to about 20 carbon atoms containing one or more heteroatoms; and,
subscript a is 0, 1 or 2.

4. The method of claim 1 , wherein the Brønsted-Lowry base is a compound having the general formula (X):
M(OR) f   (X)

wherein M is an alkali metal or alkaline earth metal and R is hydrogen, a hydrocarbon group of from 1 to about 20 carbon atoms, a heterocarbon group of up to about 20 carbon atoms, specifically from 1 to about 12 carbon atoms and still more specifically from 1 to about 6 carbon atoms, a p-orbital of the oxygen atom containing a lone paired electrons, or M, and subscript f is 1 or 2, with the provisos that (i) when M is an alkali metal, then subscript f is 1; (ii) when M is an alkaline earth metal, then subscript f is 2, except when R is a p-orbital of oxygen atom containing a lone pair of electrons; (iii) when R is M, then M is an alkali metal; and (iv) when R is a p-orbital of the oxygen atom containing a lone pair of electrons, then M is an alkaline metal and subscript f is 1; It is understood that the Brønsted-Lowry base of formula (X) is a salt of an alkali or alkaline hydroxide, alkoxide or oxide.

5. The method of claim 4 , wherein in Brønsted-Lowry base (X), M is an alkali or alkaline earth metal, R is hydrogen or a hydrocarbon group of from 1 to about 20 carbon atoms and subscript f is 1 or 2, with the provisos that when M is an alkali metal, subscript f is 1 and when M is an alkaline earth metal, subscript f is 2.

6. The method of claim 1 , wherein the Brønsted-Lowry base is at least one member selected from the group consisting of alkali metal and alkaline metal hydroxides, alkoxides and oxides.

7. The method of claim 1 , wherein the Brønsted-Lowry base is at least one member selected from the group consisting of LiOH, NaOH, KOH, CsOH, Mg(OH) 2 , Ca(OH) 2 , Ba(OH) 2 , NaOMe, KOMe, NaOEt, KOEt, CaO, MgO and BaO.

8. The method of claim 1 , wherein the amount of Brønsted-Lowry base (X) added to the imino-functional silane ranges from about 0.0001 to about 10 weight percent based upon the total weight of the imino-functional silane and Brønsted-Lowry base.

9. The method of claim 1 , wherein the Brønsted-Lowry base is soluble in the imino-functional silane at the concentration employed and matches the alkoxy functionality of the silane moiety of the imino-functional silane.

10. The method of claim 1 , wherein the stabilized imino-functional silane is an imino-functional silane containing less than about 2 weight percent conjugated carbon-carbon double bond-containing imino-functional silane based on the total weight of conjugated carbon-carbon double bond-containing imino-functional silane and imino-functional silane when stored at 25° C. for 4 weeks.

11. The method of claim 1 , wherein the stabilized imino-functional silane contains from about 0.0001 to about 0.1 weight percent of Brønsted-Lowry base based on the weight of the imino-functional silane.

12. The method of claim 1 , wherein the method further comprises neutralizing a proton source in the mixture from step (b) with at least one Brønsted-Lowry base.

13. The method of claim 1 further comprising separating the at least one Brønsted-Lowry base from the mixture of imino-functional silane with the at least one Brønsted-Lowry base after the proton source in the mixture of step (b) has been neutralized with the at least one Brønsted-Lowry base.

14. The method of claim 13 , wherein the ste

Assignees

• Momentive Performance Mat Inc

Inventors

• Cruse Richard W
• Pinnow Matthew

Classifications

• C07F7/20

  Purification, separation · CPC title

• C07F7/1872 Primary

  Preparation; Treatments not provided for in C07F7/20 · CPC title

• C07C31/04

  Methanol · CPC title

• C01D1/04

  Hydroxides · CPC title

• C01D1/02

  Oxides · CPC title