Siloxane-polyether copolymers with unsaturated functionalities, and process for making them

• US 6,103,847 A
• Filed: 05/21/1998
• Issued: 08/15/2000
• Est. Priority Date: 05/27/1997
• Status: Expired due to Term

• Current Assignee: General Electric Company
• Original Assignee: Witco Corporation (Lanxess AG)
• Inventors: Yu, Hua, Lewis, Kenrick M.
• Primary Examiner(s): Marquis, Melvyn I.
• Application Number:
  US09/082,563
• Time in Patent Office: 817 Days
• Field of Search: 528/21, 528/18
• US Class Current: 528/21
• CPC Class Codes: C08G 77/10 Equilibration processes
• CPC Class Codes: C08G 77/46 containing polyether sequences

Abstract

This invention discloses hydrophilic additives in polysiloxane gels, elastomers and coatings, and novel processes for producing them. The process comprises:

(a) redistributing into polysiloxane-polyether copolymers an unsaturated silane or siloxane,

(b) adding to the mixture of reagents a catalytically effective amount of a basic catalyst; and

(c) heating the reaction mixture to effect reaction.

Novel siloxane structures of unsaturated aliphatic modified polyerther siloxane copolymers are also taught.

Claims

1. A process for making a copolymer comprising

(a) adding to a polysiloxane-polyether copolymer an alkenyl or alkynyl silane or siloxane capable of undergoing an addition or redistribution reaction with the polysiloxane-polyether

(b) adding to the mixture formed in step (a) a catalytically effective amount of a basic catalyst;

and

(c) heating the mixture formed in step (b) to a temperature up to about 200°

C., to effect reaction to form unsaturated polysiloxane-polyether copolymer product.

2. A process in accordance with claim 1 wherein said basic catalyst is selected from the group consisting of KOH, CsOH, Ca(OH)₂, (CH₃)₄ N^+- OSi(CH₃)₃, (CH₃)₄ N^+- [OSi(CH₃)₂ ]_s^-+ N(CH₃)₄ (wherein s=4-100) and K^+- OSi(CH₃)₃.

3. A process according to claim 1 wherein the polysiloxane-polyether copolymer of step (a) is a cyclic structure which is ring opened with a disiloxane of the structure R¹ R₂ SiOSiR₂ R¹ or R₃ SiOSiR₂ R¹ with R¹ is a C₁ -C₂₀, unsaturated monovalent organic group that can be hydrosilylated to yield silicon-carbon bonds and R is a C₁ -C₂₀ saturated, monovalent organic group.

4. A process according to claim 3 wherein R¹ is a vinyl group.

5. A process according to claim 1 wherein the polysiloxane-polyether copolymer of step (a) is of the formula[R₃ SiO_1/2 ]_m [ZR₂ SiO_1/2 ]_n [O_1/2 Si(R₂)O_1/2 ]_o [O_1/2 SiRZO_1/2 ]_p [SiO_3/2 R]_q [SiO_4/2 ]_r wherein R is a C₁ -C₂₀, preferably C₁ -C₁₂, saturated, monovalent organic group, Z is a polyether-containing group that is linked to the polysiloxane block by a silicon-carbon bond, m=0 to 5, n=0 to 3;

o=0 to 100, p=0 to 30;

q=0 to 4;

r=0 to 2 and if p=0, then n>

0 and if n=0, then p=0 and m+n+o+p+q+r=3 to 100.

6. A siloxane of the structure:

R² R₂ SiO(SiR₂ O)_n (SiR¹ ZO)_m (SiR¹ RO)_p SiR₂ R² wherein n+m+p=0 to 3, each n. m, and p are 0 to 3, with the proviso that there is at least one Z and at least one R¹ per molecule and wherein R¹ is a C₁ -C₂₀, unsaturated monovalent organic group that can be hydrosilylated to yield silicon-carbon bonds, R is a C₁ -C₂₀ saturated, monovalent organic group;

Z is a polyether-containing group that is linked to the polysiloxane block by a silicon-carbon bond and R² is selected from the group consisting of R, R¹ and Z.

7. A siloxane according to claim 6 wherein Z is C_x H_2x O(C_a H_2a O)_b R" or --C_x H_2x OG[(C_a H_2a O)_b R"]_r wherein x is an integer in the range 1-20, G is a polyhydroxy group capable of being alkoxylated, a is 2 to 4, b=3 to 12, R" is hydrogen or a polyether capping group, and r, represents the number of alkoxylated hydroxyl groups on the G group.

8. A siloxane according to claim 7 wherein R² is vinyl and p=0.

9. A siloxane according to claim 8 wherein each R is methyl.