Michael addition curing chemistries for sulfur-containing polymer compositions

Patent metadata

Field	Value
Publication number	US-9388280-B2
Application number	US-201414463047-A
Country	US
Kind code	B2
Filing date	Aug 19, 2014
Priority date	Jun 21, 2012
Publication date	Jul 12, 2016
Grant date	Jul 12, 2016

Abstract

The use of Michael addition curing chemistries in compositions comprising sulfur-containing polymers such as polythioethers and polysulfides useful in aerospace sealant applications are disclosed. Sulfur-containing adducts comprising terminal Michael acceptor groups are also disclosed.

First claim

What is claimed is:

1. A polysulfide adduct comprising at least two terminal Michael acceptor groups, wherein the Michael acceptor groups comprise the structure of Formula (2):
—CH 2 —C(R 4 ) 2 —S(O) 2 —CR 4 ═CH 2   (2)

wherein each R 4 is independently selected from hydrogen and C 1-3 alkyl.

2. The polysulfide adduct of claim 1 , wherein the polysulfide adduct comprises the reaction products of reactants comprising:
(a) a thiol-terminated polysulfide polymer; and
(b) a compound comprising a Michael acceptor group and a group that is reactive with a thiol group, wherein the Michael acceptor group has the structure of Formula (2).

3. The polysulfide adduct of claim 2 , wherein the thiol-terminated polysulfide polymer comprises:
(a) from 90 mole percent to 25 mole percent of a thiol-terminated polysulfide polymer of the Formula HS(RSS) m R—SH, wherein each R is selected from C 2-12 alkanediyl, a C 4-20 thioether, a C 4-20 alkyl ether comprising one oxygen atom, a C 4-20 alkyl ether comprising 2 to 4 oxygen atoms in which each of the oxygen atoms is separated from another oxygen atom by at least 2 carbon atoms, C 6-12 alicyclic, an aromatic lower alkyl; and
(b) from 10 mole percent to 75 mole percent of a diethyl formal thiol-terminated polysulfide polymer of the Formula HS(RSS) n —R—SH, wherein each R is —C 2 H 4 —O—CH 2 —O—C 2 H 4 —,
wherein m and n are selected to provide an average molecular weight from 1,000 Daltons to 4,000 Daltons.

4. The polysulfide adduct of claim 3 , wherein R is selected from —CH 2 —CH 2 —, —C 2 H 4 —O—C 2 H 4 —, —C 2 H 4 —S—C 2 H 4 —, —C 2 H 4 —O—C 2 H 4 —O—C 2 H 4 —, and —CH 2 —C 6 H 4 —CH 2 —.

5. The polysulfide adduct of claim 2 , wherein the compound comprises divinyl sulfone.

6. A composition comprising:
(a) the polysulfide adduct of claim 1 ; and
(b) a compound having at least two Michael acceptor groups, wherein the compound having at least two Michael acceptor groups is characterized by a molecular weight less than 400 Daltons.

7. The composition of claim 6 , comprising a polyepoxy.

8. The composition of claim 6 , comprising a polyisocyanate comprising isocyanate groups, wherein the isocyanate groups are less reactive with Michael acceptor groups than with thiol groups.

9. The composition of claim 6 , comprising a polythioether polymer comprising at least two terminal groups reactive with Michael acceptor groups.

10. A composition comprising:
(a) the polysulfide adduct of claim 1 ; and
(b) a curing agent comprising at least two terminal groups that are reactive with Michael acceptor groups.

11. The composition of claim 10 , wherein the curing agent is selected from a sulfur-containing polymer comprising at least two terminal groups reactive with Michael acceptor groups, a monomeric thiol, a polythiol, a polyamine, a blocked amine, and a combination of any of the foregoing.

12. The composition of claim 10 , wherein the curing agent comprises a sulfur-containing polymer comprising at least two terminal groups reactive with Michael acceptor groups.

13. The composition of claim 12 , wherein the sulfur-containing polymer comprises a thiol-terminated polysulfide.

14. The composition of claim 12 , wherein the sulfur-containing polymer comprises a polythioether polymer.

15. The composition of claim 10 , comprising a polyepoxy.

16. The composition of claim 11 , comprising a polyisocyanate comprising isocyanate groups, wherein the isocyanate groups are less reactive with Michael acceptor groups than with thiol groups.

17. The composition of claim 10 , comprising a polythioether adduct, wherein the polythioether adduct comprises at least two terminal Michael acceptor groups.

18. A composition comprising:
(a) a sulfur-containing adduct containing at least two Michael acceptor groups, wherein the sulfur-containing adduct comprises the polysulfide adduct of claim 1 ;
(b) a sulfur-containing polymer comprising at least two terminal groups reactive with Michael acceptor groups; and
(c) a monomeric compound having at least two Michael acceptor groups.

19. A hydroxyl-terminated sulfur-containing adduct comprising the reaction products of reactants comprising:
(a) a sulfur-containing Michael acceptor adduct comprising at least two terminal Michael acceptor groups, wherein the sulfur-containing Michael acceptor adduct comprises the polysulfide adduct of claim 1 ; and
(b) a compound having a hydroxyl group and a group that is reactive with the terminal groups of the sulfur-containing Michael acceptor adduct.

20. An amine-terminated sulfur-containing adduct comprising the reaction products of reactants comprising:
(a) a sulfur-containing Michael acceptor adduct comprising at least two terminal Michael acceptor groups, wherein the sulfur-containing Michael acceptor adduct comprises the polysulfide adduct of claim 1 ; and
(b) a compound having a amine group and a group that is reactive with the terminal groups of the sulfur-containing Michael acceptor adduct.

21. A composition comprising:
(a) the amine-terminated sulfur-containing adduct of claim 20 ; and
(b) a polyisocyanate curing agent.

22. A composition comprising:
(a) a polysulfide adduct comprising at least two terminal Michael acceptor groups; and
(b) a curing agent comprising at least two terminal groups that are reactive with Michael acceptor groups,
wherein the curing agent comprises a sulfur-containing polymer comprising at least two terminal groups reactive with Michael acceptor groups;
wherein the sulfur-containing polymer comprises a thiol-terminated polysulfide; and
wherein the thiol-terminated polysulfide comprises a thiol-terminated polysulfide polymer comprising:
(a) from 90 mole percent to 25 mole percent of a thiol-terminated polysulfide polymer of the Formula HS(RSS) m R—SH, wherein R is selected from C 2-12 alkanediyl, a C 4-20 thioether, a C 4-20 alkyl ether comprising one oxygen atom, a C 4-20 alkyl ether comprising 2 to 4 oxygen atoms in which each of the oxygen atoms is separated from another oxygen atom by at least 2 carbon atoms, C 6-12 alicyclic, an aromatic lower alkyl; and
(b) from 10 mole percent to 75 mole percent of a diethyl formal thiol-terminated polysulfide polymer of the Formula HS(RSS) n —R—SH, wherein R is —C 2 H 4 —O—CH 2 —O—C 2 H 4 —,
wherein m and n are selected to provide an average molecular weight from 1,000 Daltons to 4,000 Daltons.

23. A composition comprising:
(a) a hydroxyl-terminated sulfur-containing adduct comprising the reaction products of reactants comprising:
a sulfur-containing Michael acceptor adduct comprising at least two terminal Michael acceptor groups, wherein the sulfur-containing Michael acceptor adduct comprises a polysulfide adduct comprising at least two terminal Michael acceptor groups; and
a compound having a hydroxyl group and a group that is reactive with the terminal groups of the sulfur-containing Michael acceptor adduct and

(b) a polyisocyanate curing agent.

Assignees

• Prc Desoto Int Inc

Inventors

• Anderson Lawrence G
• Cai Juexiao
• Ito Marfi
• Keledjian Raquel
• Lin Renhe

Classifications

• C08G75/12

  Polythioether-ethers (C08G75/0245 takes precedence) · CPC title

• C08G75/0222

  containing nitrogen · CPC title

• C08G75/14

  Polysulfides · CPC title

• C08G75/02 Primary

  Polythioethers · CPC title

• C08L81/04

  Polysulfides · CPC title