DE2113246C3 - Polymerization inhibited vinyl monomer composition - Google Patents

Description

R,

> 5

{ils contains inhibitor components in which R _{1 and R 2 can be} identical or different and each represent an alkyl group having 1 to 11 carbon atoms, the phenyl group or the hydrogen atom, with the proviso that if one of the substituents R ₁ and R 2 is a hydrogen atom , the other is the alkyl group or the phenyl group, or they together with the carbon atom to which they are attached constitute the group

The invention relates to a polymerization inhibited vinyl monomer composition, which is characterized in that it contains about 0.01 to 1 percent by weight of a compound of formula

(Il

35

contains, wherein R ₁ and R _{2 can be the} same or different and each represent an alkyl group having 1 to 11 carbon atoms, the phenyl group or the hydrogen atom, with the proviso that. when one of the substituents R ₁ and R _{2 is} hydrogenate then the other is alkyl group or phenyl group, or they can together with the carbon atom to which they are attached form the group

CH ₃ CH ₃

40

can form; R ₃ and R _{4 have the} same meanings as R ₁ and R ₂ ; X the group

45

- (CH 2> 3- I. 'L ti. -CH ₂ O -CH ₂ -CH, OH
I. -NH- I.
-CH O -CH, ρ _ (

55 CH ₃ CH ₃

form; R, and R ₄ have the same meanings as R ₁ and R ₂ : X represents the group

- (CH ₂ ), -

6o

CH ₃
- CH ₂ -CH-O-

represents and Y represents the hydrogen atom or the Hydroxyl group.

! I

-CH ₂ -C-CH ₂ --OH

-CH ₁ -CH-CH,

! I

NH

- CH -, - Ο—

CII,

-CH ₂ -CH-O -

dar; and Y represents hydrogen atom or hydroxyl group. ', ο

In the definition of the above formula 1, the alkyl group can be, for example, methyl, ethyl, n-propyl, isopropyl, η-butyl, isobutyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, n-nonyl, n-decyl and n-undecyl being.

The term "vinyl monomer" used herein is intended to include esters of acrylic acid and Methacrylic acid, acrylamide, acrylonitrile, methacrylonitrile, acrolein, methacrolein, butadiene, isoprene, Chloroprene, styrene, chlorostyrenes, divinylbenzene. Vinyl pyridine, vinyl chloride, vinylidene chloride, vinyl acetate, Methyl vinyl ketone and the like;

It is well known in the art that various vinyl monomers are reactive and, if left to stand under normal environmental conditions, a pronounced one Have a tendency to polymerize the same. It has therefore already been proposed this To stabilize vinyl polymers by giving them a polymerization inhibitor, such as hydroquinone, Pyrogallol, methylene blue or the like incorporated.

However, these inhibitors are not entirely satisfactory, and the need for new polymerization inhibitors has therefore always been pointed out to develop.

As a result of extensive studies on polymerization inhibitors it has now been unexpectedly found that the compounds of the above formula I to a large extent an inhibiting effect against the undesired polymerization of vinyl monomers practice, and this invention has been completed based on the above knowledge.

It is an object of the invention to provide a novel, polymerization-inhibited vinyl monomer composition to show which contains a compound of the above-mentioned formula 1 as a polymerization inhibitor.

These and other features of the invention will become apparent from the more specific description that follows.

The compounds of the above formula 1 used as a polymerization inhibitor in the present invention are known compounds other than those compounds of the above-mentioned Formula I in which X is the group

-CH ₁ O

CH ₃

-CH ₂ -CH-O-

represents.

The known compounds can be used in a manner known per se, for example according to Nippon Kagaku Zasshi (Journal of the Chemical Society of Japan). 90: 296 (1969) or Bulletin of the Chemical Society of Japan, 42 (1969), 1640, or by using a reaction of α-amino nitrile with the corresponding Aldehyde or ketone according to the following reaction scheme:

\ / ^CN

/ \
R ₂ NH ₂

O = C

wherein R ₁ , R ₂ , R ₃ and R _{4 have} the meanings described above, can be conveniently prepared. New compounds of the formula I mentioned above, in which X represents the group —CH ₂ O—, can conveniently be prepared according to the following reaction scheme:

R.

R,

CH ₇ OH

NH,

■ —ο

N
H

wherein R ₁ . R ₇ , R, and R _{a have} the meanings described above, are prepared.

New compounds of the above-mentioned formula I. in which X is the group

- CH, —CM —O— represents can conveniently according to the following reaction scheme:

R,

CH,

C-CH ₁ -CH

+ O = C

R, NH,

OH

wherein R ₁ , R ₂ , R ₃ and R _{4 have} the meanings described above, are prepared.

Representative examples of the compounds of the above-mentioned formula I, which Tfindungsgemaß as a polymerization inhibiting ingredient for vinyl monomer compositions can be used are the following:

1. 2,2,6,6-tetramethylpiperidine.

2. 4-Hydroxy-2,2,6,6-tetramethylpiperidine.

3. 2,2,6,6-tetramethyl-4-oxopiperidine.

4. 1-Hydroxy-2,2,6,6-tetramethyl-4-oxopiperidine.

5. 1 -Aza-2,2-dimethyl-4-oxo-spiro- [5,5] -undecane. . 6.l ^ -Diaza ^^ SJOJO-hexamethyM-oxo-

spiro- [5.5] undecane.

7. 2,2,5,5-tetramethyl-4-oxoimidazolidine.

8. 1,4-Diaza-2-ethyl-2-methyl-3-oxo-spiro-f 4,5] -decane.

9. 1,3-Diaza-4-oxo-2-phenyl-spiro- [4.5] -decane.

10. 1,3-Diaza-4-oxo-2-n-undecyl-spiro- [4,5] -decane.

11. Cyclohexane-1-spiro-2 '- (4'-oxoimidaiOlidine) -5'-spiro-1 "-cyclohexane.

12. 2,2,6,6-Tetramethylpiperidine-1-oxyl-4-spiro-2 '- (4'-oxoimidazoIidine) -5'-spiro-1 "-cyclohexane.

13. 2,4,4-trimethyl-2-phenyloxazolidine.

14. l-Aza-2,2-dimethyl-4-oxa-spiro- [4,4] -nonane.

15. 1 -Aza-2,2-dimethyl-4-oxa-spiro [4.5] decane.

16. 2,2,4,4,6-Pentamethyltetrahydro-1,3-oxazine.

17. l-Aza-2,2,4-trimethyl-5-oxa-spiro- [5.5] -undecane.

18. l ^ -dihydroxy ^^. O.o-tetramethylpiperidine.

19. Cyclohexane-1-spiro-2 '- (1' -hydroxy ^ '- oxoimidazolidine) -5'-spiro-1 "-cyclohexane.

The technical progress of the compounds used according to the invention is that they do not cause discoloration after incorporation into the monomers.

The preparation of the new compounds in the above information is carried out, for example, on the following Illustrations explained.

Illustration 1

1-aza-2,2-dimethyl-4-oxa-spiro [4.5] decane

(Compound no.15)

To a solution of 8.9 g of 2-amino-2-methylpropanol and 9.8 g of cyclohexanone in 150 ml of benzene 0.5 g of ammonium acetate was added and the resulting mixture was refluxed for 5 hours heated, the water formed during the reaction being separated off continuously. then the reaction mixture was distilled under reduced pressure to give 13.9 g of the desired

CH,

R ₁ ( ? R,

R ₄ R, NR ₄

Product received as a colorless liquid which boils at 64 C / 2.5 mm Hg.
Yield: 82.8%.
Analysis values for C ₁₀ H ₁₉ NO:

Calculated ... C 70.96, H 11.32. N 8.23%:
found C 71.00. H 11.35. N 8.20%.

Illustration 2

l-Aza-2.2.4-trimethyl-5-oxa-spiro- [5.5] -undecane
(Compound no.17)

To a solution of 11.7 g of 4-amino-4-methyl-2-pentanol and 9.8 g of cyclohexanone in 150 ml of benzene was added 0.5 g of ammonium acetate, and the resulting mixture was refluxed for 7 hours, the water formed during the reaction was continuously separated off. The reaction mixture was then distilled under reduced pressure, 15.5 g of the desired product being obtained as a colorless liquid which boils at 74 to 75C / 2 mm Hg.
Yield: 78.7%.
Analysis values for C ₁₂ H ₂₃ NO:

Calculated ... C 73.04, H 11.75. N 7.10%:
found .... C 73.16, H 11.76. N 7.10%.

The compounds of the formula 1 mentioned above can conveniently be converted into a vinyl monomer in a conventional manner may be incorporated at any stage during the manufacturing or purification process.

The amount of the inhibitor compound contained in the vinyl monomer composition of the present invention may vary and is usually about 0.01 to 1% by weight based on the total weight of the vinyl monomer, mainly depending on the kind of the vinyl monomer component.
To demonstrate the excellent polymerization inhibition effect of the compounds of the above formula I, after their incorporation into a vinyl monomer, the following example is given, in which the numbers assigned to the polymerization inhibitors, which can be seen from the results, are the same numbers for the inhibitors mentioned for example in the above list are.

example
Purification of vinyl monomers

The monomers to be used are commercially available, and they have been advertised twice

fication and used in the test immediately after distillation.

Test method

An appropriate one was placed in a 20 ml Jenaer glass tube Amount of the below monomer was introduced, and then that of the present invention was made Polymerization inhibitor added in an amount (weight percent) as indicated below. After tightly sealing the tube at the temperature given below during the also below given time shaken. Thereafter, the contents were in an organic solvent in which the polymer obtained is insoluble, such as methanol, poured out, after which the polymer obtained is separated and was weighed. The degree of polymerization of the monomer was determined from the weight of the obtained Polymers calculated.

1. Polymerization inhibition effect

for methyl methacrylate

Polymerization conditions: 90 ° C: 2.5 hours. The results are compiled in the table below.

Table 1

No. iles Polymcrisutions- / usal / mengc Polymeri inhibilors sation *}! riul ("'" I (%) 7th 0.2 0 10 0.2 0 11 0.1 0 13th 0.2 0 15th 0.2 0 16 Ο.] '. 0 17th 0.2 0 18th 0.1 0 19th 0.1 0

3. Effect of polymerization inhibition on styrene

Polymerization Conditions: KXFC; 2.5 hours The results are compiled in the table below.

table

No. of the polymerization inhibitor

Additional rricngc

C-OI

Degree of polarization

No. of the polymerization inhibitor

control
(no inhibitor)

Tariff quantity

0.1 0.1

0.2 0.2 0.1 0.1 0.2 0.2 0.2 0.2 0.1 0.1

Degree of polymerisation

7.35

2.44

1.23

1.53

0.30

0.43

0.55

35

40

45

2. Polymerization inhibition effect in the case of vinyl acetate

Polymerization conditions: 100'C: 3 hours. The results are compiled in the table below.

Table 2

control
(no inhibitor)
1

55

No. of the polymerization inhibitor

control
(no inhibitor)
1

Additional amount

0.1

0.1

0.05 0.1

45.5 0 0 0 0

■ 65 0.3
0.2
0.2
0.2

9.20 0.72 2.10 3.20

■ 1. Polymerization inhibition with vinylidene chloride

Polymerization conditions: 60 C; 6 hours. The results are compiled ι in Table 4 below.

Table 4

Degree of polymerization

(%)

No. of the polymerization Zusal / ncngc Polymeri inhibitors <% l degree of sation control (no inhibitor) _ .. 5.85 1 0.1 0 2 0.2 0.07 3 0.2 0 6th 0.2 0.03 8th 0.2 0 9 0.2 0.12 11th 0.1 0 15th 0.2 0 17th 0.2 0

From the above results (Tables 1 to 4) so that the compound used according to the invention a remarkable inhibitory effect on the polymerisation of various types of vinyl moi exercise mercn.

Claims (3)

Patent claims: 1. Vinyl monomer composition inhibited against polymerization, characterized, that they are about 0.01 to 1 percent by weight based on the total weight of the vinyl monomer component, a compound of the formula 2. vinyl monomer composition according to claim 1, characterized in that the Vinyl monomer component methyl methacrylate. Vinylidene chloride, styrene or vinyl acetate. 3 vinyl monomer composition according to claim 1, characterized in that the Inhibitor component 2,2,6,6-tetramethylpiperidine. 2.2.6,6-Tetramethyl-4-oxopipendin, 1-hydroxy-2,2,6, o - tetramethyl - 4 - oxopiperidine and cyclohexane-1 -spiro-2 '- (4'-oxoimidazolidine) -5'-spiro-Γ'-cvclohexane is.