Phosphine-catalyzed, michael addition-curable sulfur-containing polymer compositions

Patent metadata

Field	Value
Publication number	US-10011751-B2
Application number	US-201615060636-A
Country	US
Kind code	B2
Filing date	Mar 4, 2016
Priority date	Mar 7, 2014
Publication date	Jul 3, 2018
Grant date	Jul 3, 2018

Abstract

Compositions comprising Michael acceptor-terminated sulfur-containing prepolymers, thiol-terminated sulfur-containing prepolymers, and e phosphine catalysts useful in aerospace sealant applications are disclosed. The compositions exhibit extended pot life, cure rapidly following activation, and provide cured sealants having improved properties useful in aerospace sealant applications.

First claim

What is claimed is:

1. A composition comprising:
a Michael acceptor-terminated sulfur-containing polyformal prepolymer;
a thiol-terminated sulfur-containing prepolymer; and
a phosphine catalyst wherein the Michael acceptor-terminated sulfur-containing polyformal prepolymer comprises the reaction products of reactants comprising:
(a) a sulfur-containing polyformal prepolymer; and
(b) a compound having a terminal Michael acceptor group and a group that is reactive with a terminal group of the sulfur-containing polyformal prepolymer;
wherein the compound comprising a terminal Michael acceptor group and a group that is reactive with a terminal group of the sulfur-containing polyformal prepolymer comprises a bis(sulfonyl)alkanol, a bismaleimide, or a combination thereof.

2. The composition of claim 1 , wherein the Michael-acceptor terminated sulfur-containing polyformal prepolymer comprises a bis(sulfonyl)alkanol-terminated sulfur-containing polyformal prepolymer.

3. The composition of claim 1 , wherein the terminal Michael acceptor group comprises the structure of Formula (13a):
—CH 2 —CH 2 —S(O) 2 —R 10 —CH(—OH)—R 10 —S(O) 2 —CH═CH 2   (13a)

wherein each R 10 is independently selected from C 1-3 alkanediyl.

4. The composition of claim 3 , wherein, the terminal Michael acceptor group comprises a 1-(ethylenesulfonyl)-n-(vinylsulfonyl)alkanol group.

5. The composition of claim 3 , wherein, 1-(ethylenesulfonyl)-3-(vinylsulfonyl)propan-2-ol.

6. The composition of claim 1 , wherein the sulfur-containing polyformal prepolymer comprises a thiol-terminated sulfur-containing polyformal and the terminal group is a thiol group.

7. The composition of claim 1 , wherein the compound comprising a terminal Michael acceptor group and a group that is reactive with a terminal group of the sulfur-containing polyformal prepolymer comprises 1,3-bis(vinylsulfonyl-2-propanol, 1,1′-(methylenedi-4,1-phenylene)bismaleimide, or a combination thereof.

8. The composition of claim 1 , wherein the thiol-terminated sulfur-containing prepolymer comprises a thiol-terminated polythioether prepolymer, a thiol-terminated sulfur-containing polyformal, or a combination thereof.

9. The composition of claim 1 , wherein the thiol-terminated sulfur-containing prepolymer comprises a thiol-terminated polythioether prepolymer of Formula (7a), a thiol-terminated polythioether prepolymer of Formula (7b), or a combination thereof:
HS—R 1 —[—S—(CH 2 ) p —O—(R 2 —O) m —(CH 2 ) 2 —S—R 1 —] n —SH  (7a)

{HS—R 1 —[—S—(CH 2 ) p —O—(R 2 —O) m —(CH 2 ) 2 —S—R 1 —] n —S—V′-} z B  (7b)

wherein:
each R 1 independently is selected from C 2-10 alkanediyl, C 6-8 cycloalkanediyl, C 6-14 alkanecycloalkanediyl, C 5-8 heterocycloalkanediyl, and -[(—CHR—) s -X-] q -(—CHR—) r -, wherein:
s is an integer from 2 to 6;
q is an integer from 1 to 5;
r is an integer from 2 to 10;
each R 3 is independently selected from hydrogen and methyl; and
each X is independently selected from —O—, —S—, —NH—, and —N(—CH 3 )—;

each R 2 is independently selected from C 1-10 alkanediyl, C 6-8 cycloalkanediyl, C 6-14 alkanecycloalkanediyl, and -[(—CHR—) s -X-] q -(—CHR—) r -, wherein s, q, r, R 3 , and X are as defined for R 1 ;
m is an integer from 0 to 50;
n is an integer from 1 to 60;
p is an integer from 2 to 6;
B represents a core of a z-valent, polyfunctionalizing agent B(—V) z wherein:
z is an integer from 3 to 6; and
each —V is a group comprising a terminal group reactive with thiol groups; and

each —V′— is derived from the reaction of —V with a thiol.

10. The composition of claim 1 , wherein the phosphine catalyst comprises a tertiary n-hydroxyl-substituted alkyl phosphine.

11. The composition of claim 1 , wherein the phosphine catalyst comprises trihydroxypropyl phosphine.

12. The composition of claim 1 , wherein the composition comprises from 0.01 wt % to 0.4 wt % of the phosphine catalyst, wherein wt % is based on the total solids weight of the composition.

13. The composition of claim 1 , formulated as a sealant.

14. A cured sealant formed from the composition of claim 13 .

15. A method of sealing a surface, comprising:
applying the composition of claim 13 to at least a portion of a surface; and
allowing the composition to cure to seal the portion of the surface.

16. The composition of claim 1 , wherein the terminal Michael acceptor group comprises a bismaleimide.

17. The composition of claim 1 , wherein the terminal Michael acceptor group comprises a bismaleimide having the structure of Formula (4b), wherein R10 is a divalent organic moiety:

18. The composition of claim 1 , wherein the compound comprising a terminal Michael acceptor group comprises 1,1′-(methylenedi-4,1-phenylene)bismaleimide, ethylenebismaleimide; 1,6-bismaleimidohexane; 2,4-dimaleimidotoluene, N,N′-1,3-phenylenedimaleimide; 1,4-bis(maleimido)butane trimethylenebismaleimide; p,p′-dimaleimidodiphenylmethane; pentamethylenebismaleimide 1H-pyrrole-2,5-dione; octanediyl)bis-, 1H-pyrrole-2,5-dione; 1,1′-(1,7-heptanediyl)bis-, 4,4′-dithiobis(phenylmaleimide); methylenebis(N-carbamylmaleimide); 1,9-bis(maleimide)nonane; 1,1′-decane-1,10-diylbis(1H-pyrrole-2,5-dione); O-phenylene dimaleimide, bis(N-maleimidomethyl)ether; 1,5-bis(maleimide)-2-methyl-pentane; N,N′-1,4-phenylenedimaleimide; 1,1′-(2-methyl-1,3-phenylene)bis(1H-pyrrole-2,5-dione); tetrakis(N-2-aminoethyimaleimide); 1-(2,5-dimethylphenyl)pyrrole-2,5-dione; or 1,1-biphenyl-4,4′-diylbis(1H-pyrrole-2,5-dione).

19. The composition of claim 1 , wherein the thiol-terminated sulfur-containing
prepolymer comprises a thiol-terminated polythioether comprising a backbone comprising the structure of Formula (6):
—R′-[—S—(CH 2 ) 2 —O—[-R 2 —O-] m -(CH 2 ) 2 —S—R′] n —  (6)

wherein,
each R 1 is independently selected from a C 2-10 n-aikanediyl group, a C 3-6 branched alkanediyl group, a C 6-8 cycloalkanediyl group, a C 6-10 alkanecycloalkanediyl group, a heterocyclic group, and a -[(—CHR 3 —) p -X-] q -(—CHR 3 —) r - group, wherein each R 3 is selected from hydrogen and methyl;
each R 2 is independently selected from a C 2-10 n-alkanediyl group, a C 3-6 branched alkanediyl group a C 6-8 cycloalkanediyl group, a C 6-14 alkanecycloalkanediyl group a heterocyclic group, and a -[(—CH 2 —) p -X-] q -(—CH 2 —) r - group;
each X is independently selected from O, S, —NH—, and —N(—CH 3 )—;
m ranges from 0 to 50;
n is an integer ranging from 1 to 60;
p is an integer ranging from 2 to 6;
q is an integer ranging from 1 to 5; and
r is an integer ranging from 2 to 10.

20. An aerospace vehicle comprising the cured sealant of claim 14 .

21. The composition of claim 1 , wherein the Michael acceptor-terminated sulfur-containing polyformal prepolymer comprises a Michael acceptor-terminated sulfur-containing polyformal prepolymer of Formula (Ia), a Michael acceptor-terminated sulfur-containing polyformal prepolymer of Formula (Ib), or a combination thereof:

wherein:
n is an integer selected from 1 to 50;
each p is independently selected from 1 and 2;
each R 1 is independently selected from C 2-6 alkanediyl;
each R 2 is independently selected from hydrogen, C 1-6 alkyl, C 7-12 phenylalkyl, substituted C 7-12 phenylalkyl, C 6-12 cycloalkylalkyl, substituted C 6-12 cycloalkyla

Assignees

• Prc Desoto Int Inc

Inventors

• Anderson Lawrence G
• Cai Juexiao
• Bowman Mark P
• Lin Renhe

Classifications

• C09J181/02 Primary

  Polythioethers; Polythioether-ethers · CPC title

• C08G75/02 Primary

  Polythioethers · CPC title

• C09D4/00

  Coating compositions, e.g. paints, varnishes or lacquers, based on organic non-macromolecular compounds having at least one polymerisable carbon-to-carbon unsaturated bond {; Coating compositions, based on monomers of macromolecular compounds of groups C09D183/00 - C09D183/16} · CPC title

• C09J5/00

  Adhesive processes in general; Adhesive processes not provided for elsewhere, e.g. relating to primers · CPC title

• C08L81/00

  Compositions of macromolecular compounds obtained by reactions forming in the main chain of the macromolecule a linkage containing sulfur with or without nitrogen, oxygen or carbon only; Compositions of polysulfones; Compositions of derivatives of such polymers · CPC title