Method for the preparation of an alkoxy-functional organohydrogensiloxane oligomer and use of said oligomer

Patent metadata

Field	Value
Publication number	US-11168181-B2
Application number	US-202017269125-A
Country	US
Kind code	B2
Filing date	Sep 2, 2020
Priority date	Sep 11, 2019
Publication date	Nov 9, 2021
Grant date	Nov 9, 2021

Abstract

A method for the preparation of an alkoxy-functional hydrogensiloxane oligomer includes reacting a polyorganohydrogensiloxane oligomer and an aliphatically unsaturated alkoxysilane in the presence of a hydrosilylation reaction and a promoter. The resulting crude reaction product is treated with a treating agent, and thereafter distilled to produce the alkoxy-functional organohydrogensiloxane oligomer. The alkoxy-functional hydrogensiloxane oligomer can be reacted with polyorganosiloxane having an aliphatically unsaturated monovalent hydrocarbon group to form a polyalkoxy-functional polyorganosiloxane. The polyalkoxy-functional polyorganosiloxane can be formulated in condensation reaction curable compositions.

First claim

The invention claimed is:

1. A method for preparing a product comprising an alkoxy-functional organohydrogensiloxane oligomer, where the method comprises:
1) reacting starting materials comprising:
(A) a polyorganohydrogensiloxane oligomer of unit formula: (HR 1 2 SiO 1/2 ) e (R 1 3 SiO 1/2 ) f (HR 1 SiO 2/2 ) g (R 1 2 SiO 2/2 ) h (R 1 SiO 3/2 ) i (HSiO 3/2 ) j (SiO 4/2 ) k where subscripts e, f, g, h, i, j, and k have values such that 5≥e≥0, 5≥f≥0, 10≥g≥0, 5≥h≥0, subscript i is 0 or 1, 5≥j≥0, subscript k is 0 or 1, with the proviso that a quantity (e+g+j)≥2, and a quantity (e+f+g+h+i+j+k)≤50; and each R 1 is independently selected from group consisting of a monovalent hydrocarbon group of 1 to 18 carbon and a monovalent halogenated hydrocarbon group of 1 to 18 carbon atoms; and
(B) an aliphatically unsaturated alkoxysilane of formula:

 where R 1 is as described above, R 2 is an aliphatically unsaturated monovalent hydrocarbon group of 2 to 18 carbon atoms, each R 3 is independently a monovalent hydrocarbon group of 1 to 18 carbon atoms, and subscript c is 0 or 1;
in the presence of
(C) a platinum group metal catalyst; and
(D) a hydro(acyloxy)-functional silicon compound of formula:

 where each R 5 is independently a monovalent hydrocarbon group of 1 to 18 carbon atoms or a monovalent halogenated hydrocarbon group of 1 to 18 carbon atoms, and R 6 is a monovalent hydrocarbon group of 1 to 18 carbon atoms, thereby preparing a reaction product comprising the alkoxy-functional organohydrogensiloxane oligomer; and thereafter

2) treating the reaction product prepared in step 1) with a treating agent comprising
(E) a sorbent selected from the group consisting of
(E-1) an activated carbon,
(E-2) an ion exchange resin,
(E-3) a compound of formula NR 8 x R 9 y R 10 (3-x-y) , where R 8 , R 9 , and R 10 are each independently selected from the group consisting of a hydrogen atom and a monovalent hydrocarbon group of 1 to 18 carbon atoms, subscript x is 0 to 3, subscript y is 0 to 3, and a quantity (x+y)≤3;
(E-4) a compound of formula

 where R 11 is selected from the group consisting of a hydrogen atom and a monovalent hydrocarbon group of 1 to 18 carbon atoms, and R 12 is a divalent hydrocarbon group of 1 to 18 carbon atoms; and
(E-5) a combination of two or more of (E-1) to (E-4); and

(F) a compound of formula HOR 7 , where R 7 is a hydrogen atom or a monovalent hydrocarbon group of 1 to 18 carbon atoms, thereby preparing the product comprising the alkoxy-functional organohydrogensiloxane oligomer; and

3) distilling the product of step 2), thereby recovering the alkoxy-functional organohydrogensiloxane oligomer.

2. The method of claim 1 , where (E) the treating agent comprises ammonia (NH 3 ).

3. The method of claim 1 , where (F) the compound of formula HOR 4 is water or methanol.

4. The method of claim 1 , where the alkoxy-functional organohydrogensiloxane oligomer has unit formula:

(HR 1 2 SiO 1/2 ) n (R 1 3 SiO 1/2 ) f (HR 1 SiO 2/2 ) o (R 1 2 SiO 2/2 ) h (R 1 SiO 3/2 ) i (HSiO 3/2 ) p (SiO 4/2 ) k , where
R 1 , R 3 , and subscripts c, f, h, i, and k are as described above, subscript b is 0 to 2, m>0, and a quantity (m+n+o+p)=(e+g+j), and each D is independently a divalent hydrocarbon group of 2 to 18 carbon atoms, with the proviso that >90 mol % of all D groups produced in step 1) are linear.

5. The method of claim 1 , where (A) the polyorganohydrogensiloxane oligomer has formula:

where subscript a is 0 to 10.

6. The method of claim 5 , where the alkoxy-functional organohydrogensiloxane oligomer has formula:

where D is a divalent hydrocarbon group of 2 to 18 carbon atoms.

7. The method of claim 1 , where (A) the polyorganohydrogensiloxane oligomer has unit formula:
(HR 1 2 SiO 1/2 ) 3 (R 1 2 SiO 2/2 ) q (R 1 SiO 3/2 ), where subscript q is 0 to 3.

8. The method of claim 7 , where (A) the polyorganohydrogensiloxane oligomer has formula:

9. The method of claim 8 , where alkoxy-functional organohydrogensiloxane oligomer has formulae comprising:

where each D is independently a divalent hydrocarbon group of 2 to 18 carbon atoms, with the proviso that >90 mol % of D are linear divalent hydrocarbon groups.

10. The method of claim 1 , where the organohydrogensiloxane oligomer is a cyclic organohydrogensiloxane oligomer of unit formula: (R 1 2 SiO 2/2 ) v (R 1 HSiO 2/2 ) s , where subscript s≥3, and subscript v≥0.

11. The method of claim 10 , where the alkoxy-functional organohydrogensiloxane oligomer has unit formula: (R 1 2 SiO 2/2 ) v (R 1 HSiO 2/2 )

where subscript t≥0, subscript u≥1, and a quantity (t+u)=s.

12. The method of claim 1 , where step 2) is performed directly after step 1) without a purification step after step 1) and before step 2).

13. A method for preparing a polyalkoxy-functional polyorganosiloxane, where the method comprises:
(1) preparing an alkoxy-functional organohydrogensiloxane oligomer by a method comprising
1) reacting starting materials comprising:
(A) a polyorganohydrogensiloxane oligomer of unit formula: (HR 1 2 SiO 1/2 ) e (R 1 3 SiO 1/2 ) f (HR 1 SiO 2/2 ) g (R 1 2 SiO 2/2 ) h (R 1 SiO 3/2 ) i (HSiO 3/2 ) j (SiO 4/2 ) k where subscripts e, f, g, h, i, j, and k have values such that 5≥e≥0, 5≥f≥0, 10≥g≥0, 5≥h≥0, subscript i is 0 or 1, 5≥j≥0, subscript k is 0 or 1, with the proviso that a quantity (e+g+j)≥2, and a quantity (e+f+g+h+i+j+k)≤50; and each R 1 is independently selected from group consisting of a monovalent hydrocarbon group of 1 to 18 carbon and a monovalent halogenated hydrocarbon group of 1 to 18 carbon atoms; and
(B) an aliphatically unsaturated alkoxysilane of formula:

 where R 1 is as described above, R 2 is an aliphatically unsaturated monovalent hydrocarbon group of 2 to 18 carbon atoms, each R 3 is independently a monovalent hydrocarbon group of 1 to 18 carbon atoms, and subscript c is 0 or 1;
in the presence of
(C) a platinum group metal catalyst; and
(D) a hydro(acyloxy)-functional silicon compound of formula:

 where each R 5 is independently a monovalent hydrocarbon group of 1 to 18 carbon atoms or a monovalent halogenated hydrocarbon group of 1 to 18 carbon atoms, and R 6 is a monovalent hydrocarbon group of 1 to

Assignees

• Dow Silicones Corp

Inventors

• Zhou Xiaoyuan
• Haghpanah Reza
• Greiner Aaron
• Joffre Eric
• Reisch Sean
• Marchand Christine

Classifications

• C08G77/18 Primary

  to alkoxy or aryloxy groups · CPC title

• C08G77/34

  Purification · CPC title

• C08G77/50

  by carbon linkages · CPC title

• C08K5/5415

  containing at least one Si—O bond · CPC title

• C07F7/1876

  by reactions involving the formation of Si-C linkages · CPC title