Polymerisation inhibitor

• US 20060167244A1
• Filed: 05/30/2003
• Published: 07/27/2006
• Est. Priority Date: 06/13/2002
• Status: Abandoned Application

• Current Assignee: A H Marks & Company Limited
• Original Assignee: A H Marks & Company Limited
• Inventors: Loyns, Colin, Philips, Emyr
• Application Number:
  US10/516,979
• Publication Number:
  US 20060167244A1
• Time in Patent Office: Days
• US Class Current: 540/450
• CPC Class Codes: C07D 205/04 having no double bonds between ring members or between ring members and non-ring members
• CPC Class Codes: C07D 207/04 having no double bonds between ring members or between ring members and non-ring members
• CPC Class Codes: C07D 207/20 with only hydrogen atoms, hydrocarbon or substituted hydrocarbon radicals, directly attached to ring carbon atoms
• CPC Class Codes: C07D 209/04 Indoles; Hydrogenated indoles
• CPC Class Codes: C07D 209/86 with only hydrogen atoms, hydrocarbon or substituted hydrocarbon radicals, directly attached to carbon atoms of the ring system
• CPC Class Codes: C07D 211/94 Oxygen atom, e.g. piperidine N-oxide
• CPC Class Codes: C07D 215/58 with hetero atoms directly attached to the ring nitrogen atom
• CPC Class Codes: C07D 225/02 not condensed with other rings
• CPC Class Codes: C07D 295/027 containing only one hetero ring
• CPC Class Codes: C07D 295/24 Oxygen atoms
• CPC Class Codes: C08K 5/3412 having one nitrogen atom in the ring

Abstract

A polymerisation inhibitor comprising a non-hindered cyclic hydroxylamine either alone or in combination with an additional inhibitor.

Claims

1. A method for inhibiting the polymerisation of one or more ethylenically unsaturated monomers selected from the group consisting of:

styrene, α

-methylstyrene, styrene sulphonic acid, vinyltoluene, divinylbenzenes, polyvinylbenzenes, alkylated styrene, 2-vinylpyridine, acrylonitrile, methacrylonitrile, methyl acrylate, ethyl acrylate, methyl methacrylate, ethyl methacrylate, acrylic acid, and methacrylic acid;

by adding to the monomers an effective amount sufficient to inhibit polymerisation of a non-hindered cyclic hydroxylamine, alone or in combination with an additional inhibitor.

2. A method as claimed in claim 1, wherein the non-hindered cyclic hydroxylamine has no alkyl or other substituents alpha to the hydroxylamine group.

3. A method as claimed in claim 2, wherein the cyclic hydroxylamine has the formula (1).

wherein X is a group selected from (CH₂)_mY(CH₂)_n where m and n are each independently an integer from 0 to 5 and Y is a CH₂, or hetero atom such as O, S or NH and wherein one or more CH₂ is optionally substituted with one or more C₁ to C₅ alkyl groups, (CH₂)_r—

CH═

CH—

(CH₂)_s where r and s are independently integers from 0 to 3, optionally substituted with one or more C₁ to C₅ alkyl groups.

4. A method as claimed in claim 3 wherein the cyclic hydroxylamine is selected from the group consisting of 1-hydroxypiperidine, 4-hydroxymorpholine, 1-hydroxypyrrolidine, 1-hydroxyazetidine, 1-hydroxy-2,5-dihydropyrrole, 1-hydroxyhexamethylene imine and 1-hydroxyazocan.

5. A method as in claim 2 wherein the cyclic hydroxylamine is selected from the group consisting of 1-hydroxy-2,3,4-trihydroquinoline, 9-hydroxycarbazole and 1-hydroxy-2,3-dihydroindole, optionally substituted with one or more C₁ to C₅ alkyl groups and mixtures thereof.

6. A method as claimed in claim 4, wherein the hydroxylamine is selected from the group consisting of:

1-hydroxypiperidine, 4-hydroxmorpholine and mixtures thereof.

7. A method as claimed in claim 1, wherein the additional inhibitor is selected from the group consisting of phenols, nitrosophenols, nitrophenols, substituted nitrophenols, quinones, stable free radicals and phenylene diamines.

8. A method as claimed in claim 7, wherein the additional inhibitor is selected from the group consisting of:

2,4-dinitrophenol, 4,6-dinitro-o-cresol, 2,6-dinitro-p-cresol, 2-secbutyl-4,6-dintrophenol, tempo, 4-hydroxytempo, 4-oxotempo, 4-aminotempo and 4-methoxytempo.

9. A method as claimed in claim 1, wherein the amount of additional inhibitor in the range from a trace of 96% by weight of the total amount of inhibitor.

10. A method as claimed in claim 9, wherein the amount of additional inhibitor is 40 to 96% by weight of the total amount of inhibitor.

11. A method as claimed in claim 1 wherein the ethylenically unsaturated monomer is styrene.

12. A method as claimed in claim 1, wherein the non-hindered cyclic hydroxylamine is 1-hydroxypiperidine or 4-hydroxymorpholine.

13. A polymerisation inhibitor composition comprising an ethylenically unsaturated monomer selected from the group consisting of:

styrene, α

-methylstyrene, styrene sulphonic acid, vinyltoluene, divinylbenzenes, polyvinylbenzenes, alkylated styrene, 2-vinylpyridine, acrylonitrile, methacrylonitrile, methyl acrylate, ethyl acrylate, methyl methacrylate, ethyl methacrylate, acrylic acid, and methacrylic acid; and

an effective amount sufficient to inhibit polymerisation of a non-hindered cyclic hydroxylamine, alone or in combination with an additional inhibitor.

14. An inhibitor as claimed in claim 13, wherein the non-hindered cyclic hydroxylamine has no alkyl or other substituents alpha to the hydroxylamine group.

15. An inhibitor as claimed in claim 14, wherein the cyclic hydroxylamine has the formula (1).

wherein X is a group selected from (CH₂)_mY(CH₂)_n where m and n are each independently an integer from 0 to 5 and Y is a CH₂, or hetero atom such as O, S or NH and wherein one or more CH₂ is optionally substituted with one or more C₁ to C₅ alkyl groups, (CH₂)_r—

CH═

CH—

(CH₂)_s where r and s are independently integers from 0 to 3, optionally substituted with one or more C₁ to C₅ alkyl groups.

16. An inhibitor as claimed in claim 15 wherein the cyclic hydroxylamine is selected from the group consisting of:

1-hydroxypiperidine, 4-hydroxymorpholine, 1-hydroxypyrrolidine, 1-hydroxyazetidine, 1-hydroxy-2,5-dihydropyrrole, 1-hydroxyhexamethylene imine and 1-hydroxyazocan.

17. An inhibitor as in claim 16 wherein the cyclic hydroxylamine is selected from the group consisting of 1-hydroxy-2,3,4-trihydroquinoline, 9-hydroxycarbazole and 1-hydroxy-2,3-dihydroindole, optionally substituted with one or more C₁ to C₅ alkyl groups and mixtures thereof.

18. An inhibitor as claimed in claim 16, wherein the hydroxylamine is selected from the group consisting of:

1-hydroxypiperidine, 4-hydroxmorpholine and mixtures thereof.

19. An inhibitor as claimed in claim 13, wherein the additional inhibitor is selected from the group consisting of:

phenols, nitrosophenols, nitrophenols, substituted nitrophenols, quinones, stable free radicals and phenylene diamines.

20. An inhibitor as claimed in claim 19, wherein the additional inhibitor is selected from the group consisting of:

2,4-dinitrophenol, 4,6-dinitro-o-cresol, 2,6-dinitro-p-cresol, 2-secbutyl-4,6-dintrophenol, tempo, 4-hydroxytempo, 4-oxotempo, 4-aminotempo and 4-methoxytempo.

21. An inhibitor as claimed in claim 13, wherein the amount of additional inhibitor in the range from a trace of 96% by weight of the total amount of inhibitor.

22. An inhibitor as claimed in claim 21, wherein the amount of additional inhibitor is 40 to 96% by weight of the total amount of inhibitor.

23. An inhibitor as claimed in claim 15, wherein the ethylenically unsaturated monomer is styrene.

24. An inhibitor as claimed in claim 15 wherein the non-hindered cyclic hydroxylamine is 1-hydroxypiperidine or 4-hydroxymorpholine.