DE2148185C3 - POLYMERIZATION INHIBITOR FOR POLYMERIZABLE VINYL-BASED ALIPHATIC, AROMATIC AND HETEROCYCLIC COMPOUNDS - Google Patents

Description

wherein R is alkyl radicals having 1 to 4 carbon atoms

η 1, 2 or 3 and m 1 or 2 and A) 10 to 90 parts by weight of thiobisphenol of the all-

B) 90 to 10 parts by weight of p-alkoxyphenol of the general formula

general formula (HO) m _v , / v- ^{(OH) ni}

■. ^ao Λ V- S - / "

RO - ^ y - OH I

wherein R 'is an alkyl radical with 1 to 4 carbon atoms R »^^ R _n
represents.

2. Polymerization inhibitor according to claim 1, »5 wherein R is alkyl radicals having 1 to 4 carbon atoms, characterized by a mixture which denotes the grain η = 1, 2 or 3 and m = 1 or 2, and components A and B im Ratio 30:70 to 70:30 B) 90 to 10 parts by weight of p-alkoxyphenol containing. general formula

3. Use of a polymerization inhibitor ₍ / - ^

according to claims 1 and 2 in an amount of 0.001 30 RO - <^ J> OH
to 0.1 percent by weight, preferably 0.03 to 0.06 percent by weight, based on the monomer. where R 'is an alkyl radical with 1 to 4 carbon atoms

4. Polymerization inhibitor according to claim 1 represents.

to 3, characterized in that the mixture The mixture according to the invention, with which the Sta-

from components A and B in a saturation of monomers containing vinyl groups

th or unsaturated chlorinated hydrocarbons, which are considerably less effective against undesired polymerisation

1 or 2 carbon atoms is dissolved. is improved, shows a strong synergistic effect,

which is retained even in the presence of iron or iron compounds.

40 It has proven to be useful if that

synergistic mixture according to the invention, the components A and B mentioned preferably in the ratio

It is known that premature polymerization is from 30:70 to 70:30. The polymerization-polymerizable compounds, for example w ".S- inhibitor, will be used in an amount of 0.001 to late storage or transport, optionally 0.1 percent by weight, preferably 0.03 to 0.06 by weight, even during production - percent, based on the monomer used,
the monomers, an undesirable phenomenon. As thiobisphenols, for example, di- (t-bu-It can be rubber or resin-like products ent- tyl-p-cresol) monosulfide, di- (m-cresol) monosulfide, which by the action of air, light, tempe - Di-thymol monosulfide, di- (pt-butyl-pyrocatechol) -rature and various impurities are caused on the monosulfide monosulfide and di-carvacrol monosulfide used. The monomer will be.

therefore usually by adding certain poly- Suitable p-alkoxyphenoIe are p-ethoxy and

merization inhibitor against such a prepolymer p-methoxyphenol, p-methoxyphenol being preferred

stabilized. The aim is to use the stabilizer.

be as soluble as possible in the monomer, around an equal 55 The mixture becomes the monomer in substance

ensure moderate distribution. added, but can also be used to mediate a solution in

A well-known stabilizing agent is the phenol, dissolved in chlorinated hydrocarbons. For

(German interpretation document 1 215 134). This polymer is used for this purpose.

Sationhemmer has the disadvantage that it is in the Mono ten A and B, preferably in a saturated or

meren is poorly soluble and, moreover, in the presence of 60 unsaturated chlorinated hydrocarbons, the 1 or

of iron or iron compounds in its stabili- contains 2 carbon atoms, dissolved.

sizing effect is severely impaired. Also the mixture according to the invention for prevention

when using p-methoxyphenol (German undesirable polymerization is used

Auslegeschrift 1 197 445) is the effectiveness of polymerizable vinyl group-containing aliphatics,

Stabilizer in the presence of iron compounds 65 aromatics and heterocycles.

strong back. This also applies to the well-known micro-aliphatics containing vinyl groups:

mixtures of p-methoxyphenol and ammonia, the vinylidene halides, such as vinylidene chloride, bromide

used to stabilize vinylidene chloride and fluoride; Vinyl esters of inorganic acids,

• · wise of the hydrohalic acids and cyanomerized. The yield of polyvinyl Chemical acid such as vinyl chloride, vinyl bromide, acrylic chloride without the addition of a polymerization inhibitor wassers »." - ^^! "^" 1; vinyl ester of the monocarbon as 100 percent by weight assumed. For the nachnitnl U ". ^ /; "" Io ".iat. Vinvlbutvrat. Vinvlrjronionat. the stabilizing agents mentioned above arise

the following yields.

Polymerization inhibitor

2,2'-thiobis (4-methyl- 6-t-butylphenol)

p-methoxyphenol

2,2'-thiobis (3-methyl-4-propyl-6-t-butylphenol)

p-n-butoxyphenol

6,6'-thiobium: s- (4-methyl- catechol)

p-ethoxyphenol

_like vinyl acetate, vinyl butyrate, vinyl propionate, vnvl2-ethylhexoate, vinyl isotridecanoic acid ester,

chloroacetate, vinyl valerate, and vinyl caproate; Vinyl-

tpr of polybasic carboxylic acids such as divinyl; nat divinyl adipate, vinyl methallyl pimelate and methyl glutarate; Vinyl esters of the unsaturated "" ren such as vinyl acrylate, vinyl crotonate and vinyl SEi; Vinyl ethers, such as vinyl ethyl ether, vinyl fSf and vinyl allyl ether; Vinyl ketones such as butyl ketone and vinyl ethyl ketone; Allyl derivatives,

• Allyl acetate, ayl butyrate, diallyladipate, meth-sylpropionate, allyl chloride, methallyl chloride AlIyJ-

^ IaL methacrylate; conjugated polyenes, ! ^ Butadiene and chloroprene; Ethylenically unsaturated rarhonic and dicarboxylic acids and their anhydrides

"A ester z. B. acrylic acid, methacrylic acid, fumaric acid, maleic acid, itaconic acid, crotonic acid, unsaturated aldehydes such as acrolein, methacrolein and

^At least aromatic compounds containing vinyl groups are styrene, H its derivatives, such as ethylene - * - methylstyrene, nichlorostyrene, divinylbenzene, vinylphenol, trivinylbenzene; Vinyl naphthalene, divinyl naphthalene and vinyl

^dlP Al ^C s ⁿ vinyl group-containing heterocycles can be used, for example, vinyl imidazole and vinyl pyridines

^ The polymerization inhibitor according to the invention is preferably used, however, in the case of vinyl chloride, Vinylidene chloride and vinyl acetate as well as mixtures from these monomers. .

The synergistic 35 _{Q without additives is particularly beneficial} Mixture in the stabilization of moist raw _methoxypneno i

vinyl chloride. This according to the classical synthesis £ _{methoxyphenol}

from hydrogen chloride and acetylene or from _Ammomak

Dehydrochlorination of 1,2-dichloroethane, produced, _{2 2} '.thiobis- (4-methyl-

must mostly for the purpose of neutralization with dilute 40 ' ₆ _ _t _ _butylphenol ) ....

Lye washed and in a dewatering column _{2 2} '. _Thiobis. (4. _Me thyl-

dewatered azeotropically, while at the same time even- ' ₆ . _t . _butylphe nol)

Any low boilers present are separated off. _Tetralm

Now it is known that moist raw vinyl chloride is particularly _{2 2} <_ _Th i _o bis- (4-methyl-. ..-.: _- ^ .. ^; "; ct whereby in the" ₆ _ _t _ _buty i _{phenol )} ....

Diphenylamine

indulin

Tetralin

2,2'-thiobis (4-methyl-6-t-butylphenol)

Table la (effect of the polymerization inhibitors according to the invention)

Concentration (in percent by weight based on vinyl chloride)

Yield of polyvinyl chloride in percent by weight

0.025 \ 0.025 /

0.025 \ 0.025 J.

0.025 0.025

21

26th

22nd

Table Ib (comparative tests)

30th

Polymerization inhibitor

Concentration (in percent by weight based on vinyl chloride)

0.05 0.025 0.025

0.05

0.025 0.025

Γ same parts J «

indulin

Tetralin J overall

2,2'-thiobis (3-methyl-

> ropyl-6-t-butylphenol) 6,6'-thiobis (4-methyl- catechol)

Table 1 a, in which as

Yield of polyvinyl chloride in percent by weight

100 46

44

50

67

0.0125 0.0125 0.0125 0.0125

0.05

42

40

55

52

which is prone to polymerisation, azeotropic dewatering of the crude vinyl chloride columns made of stainless steel, but in particular those made of Iron can be laid with polymer. The use of the stabilizer mixture according to the invention makes it possible to polymerize column 50 bottom and lines of the distillation plant even at higher temperatures and in the presence of Avoided iron. This means that relatively cheap iron distillation systems can be used, which, if conventional stabilizers are used, usually take a short time Time had to be cleaned in a costly manner, operated over long periods of time without cleaning, laoeue la, uci uw «..» ~ v ^

The mode of action of the inventive poly- polymerization inhibitor used merization inhibitor results from the following 60, show compared to the tests indicated for comparison. conducted trials (Table 1 b) the superiority

". . , “Of the mixtures according to the invention.

Example I.

500 g vinyl chloride are after the block poly B e i s ρ i e 1 2

merization process together with 0.5 g of azodiiso- 65 Analogously to Example 1, the experiments are carried out in counterbutyronitrile and in the presence of 0.05 g of 1 g iron powder-rust mixture (1: 1) again of the polymerization inhibitors listed below, over 10 hours at 70 ° C in a stirred autoclave poiy-

0.05

0.05

Stabilizers compared to the ishemmer used because of their superiority

olt. Table 2 a shows the results with the inventive

according to polymerization inhibitors, while Table 2b shows the results with the comparison inhibitors shows.

Table 2a Conc yield tration Polyvinyl (in weight chloride percent in weight Polymerization inhibitor related to percent vinyl chloride) 2,2'-thiobir- (4-methyl- 0.025 \
0.025] 23 6-t-butylphenol) p-methoxyphenol 0, f> 25 1
0.025 / (»Σ 2,2'-thiobis (3-methyl- 25th 4-propyl-6-t-butylphenol) 0.025 \ p-n-butoxyphenol 0.025} 6,6'-thiobis (4-methyl- 23 catechol) p-Athoxyphenol

weight percent assumed. For the below mentioned stabilizers result in the following yields:

Table 3 a (Effect of the polymerization inhibitor according to the invention)

Table 2b

Conc yield tration Polyvinyl (in weight chloride Polymerization inhibitor percent in weight related to percent vinyl chloride 75 p-methoxyphenol 0.05 p-methoxyphenol 0.025 \ 73 ammonia 0 025 [ 2,2'-thiobis (4-methyl- 60 6-t-butylphenol) 0.05 2,2'-thiobis (4-methyl- 6-t-butylphenol) 0.025 \ OO Tetralin C 025 I. 2,2'-thiobis (4-methyl- 6-t-butylphenol) 0.0125 ) Diphenylamine 0.0125 I. 55 Indulin 0.0125 f Tetralin 0.0125 J. 2,2'-thiobia- (4-methyl- 6-t-butylphenol) 50 Indulin \ equal parts 0.05 Tetralin / total 2,2'-thiobis- (3-methyl- '\ 60 4-propyl-6-t-butylphenol) 0.05 6,6'-thiobis (4-methyl- 58 catechol) 0.05

Polymerization inhibitor

2,2'-thiobis (4-methyl-

6-t-butylphenol)

p-methoxyphenol

ao 2,2'-thiobis (3-methyl-4-propyl-6-t-butylphenol)

p-n-butoxyphenol

6,6'-thiobis (4-methyl-

catechol)

as p-ethoxyphenol

concentration (in percent by weight related to Vinyl chloride)

0.025 \
0.025 y

0.025 \
0.025 y

0.025 \
0.025 y

Yield of polyvinyl chloride in percent by weight

Table 3 b (comparative tests)

The results of Table 2 a show that the mixtures according to the invention even in the presence of Iron and iron compounds are fully effective.

Example 3

Instead of the block polymerizations carried out in Examples 1 and 2, those according to the invention are used Polymerization inhibitors as part of a suspension polymerization, tested.

500 g of vinyl chloride together with 0.5 g Azodusobuttersäurenitrii and in the presence of 0.05 g of one of the below polymerization for 10 hours at 70 ⁰ C polymerized in stirred autoclave. The yield of polyvinyl chloride without the addition of a polymerization inhibitor is 100 Ge

35 Without addition Conc yield p-methoxyphenol tration Polyvinyl 40 p-methoxyphenol (in weight chloride Polymerization inhibitor ammonia percent in weight 2,2'-thiobis (4-methyl- related to percent 6-t-butylphenol) vinyl 2,2'-thiobis (4-methyl- chloride) 100 45 6-t-butylphenol) 0 44 Tetralin 0.05 Λ1 2,2'-thiobis (4-methyl- 0.025 \
0.025 ί 6-t-butylphenol) Diphenylamine 0.05 50 5 ° indulin Tetralin 0.025 \ £ Q 2,2'-thiobis (4-methyl- 0.025 ί OO 6-t-butylphenol) vjvwar J Indulin 1 equal parts 0.0125 ) 55 Tetralin J in total 0.0125 I. / 11 2,2'-thiobis (3-methyl- 0.0125 41 4-propyl-6-t-butylphenol) 0.0125 J. 6,6'-thiobis (4-methyl- catechol) 0.05 40 0.05 54 0.05 53

The suspension polymerization is carried out as in Example 2 in the presence of 1 g of iron powder and rust mixture (1: 1) carried out. Table 4a shows the results with the inhibitors according to the invention while Table 4b shows tests with comparative materials.

2 148 185 8th 7th Table 5 Table 4 a

Polymerization inhibitor Conc
tration
(in weight
percent
related to
vinyl
chloride) yield
Polyvinyl
chloride
in weight
percent 2,2'-thiobis (4-methyl-
6-t-butylphenol)
p-methoxyphenol
2,2'-thiobis (3-methyl-
4-propyl-6-t-butylphenol)
pn-butoxyphenol
6,6'-thiobis (4-methyl-
catechol)
p-ethoxyphenol 0.025 \
0.025 y
0.025 \
0.025 y
0.025 \
0.025 y 20th
25th
19th

Polymerization inhibitor Conc
tration
Ppm by weight Period of time
lake. 2,2'-thiobis (4-methyl-
6-t-butylphenol)
p-methoxyphenol
2,2'-thiobis (4-methyl-
¹⁰ 6-t-butylphenol)
p-methoxyphenol
Without addition 100
100
50 1
50 y
0 100
110
150
58

Table 5 shows that when polymerizing vinyl acetate with the addition of the Mixtures according to the invention a strong polymerization inhibition occurs.

Table 4 b Conc yield tration Polyvinyl (in weight chloride percent in weight Polymerization inhibitor related to percent vinyl chloride) 75 0.05 η p-methoxyphenol 0.025 \ / Z p-methoxyphenol 0.025 y ammonia 61 2,2'-thiobis (4-methyl- 0.05 6-t-butylphenol) 2,2'-thiobis (4-methyl- 0.025 \ / U 6-t-butylphenol) 0.025 y Tetralin 2,2'-thiobis (4-methyl- 0.125 -ι « 6-t-butylphenol) 0.125 \ Diphenylamine 0.125 f Indulin 0.125 y Tetralin 2,2'-thiobis (4-methyl- 48 6-t-butylphenol) 0.05 Indulin 1 equal parts Tetralin J overall 62 2,2'-thiobis (3-methyl- 0.05 4-propyl-6-t-butylphenol) 60 6,6'-thiobis (4-methyl- 0.05 catechol)

Example 5

100 cm ^{3 of} styrene are dissolved together with 60 mg of Dia ₅ benzoyl peroxide in 200 cm ^{3 of} methanol and polymerized for 1 hour at 100 ° C. and then the polystyrene formed is filtered off through a glass filter crucible. If the yield of polystyrene without the addition of a stabilizer is assumed to be 100 percent by weight, the following yields result when the following polymerization inhibitors are added:

Table 6

Polymerization inhibitor Conc
tration
(in weight
percent
related to
Styrene) yield
Polystyrene
in weight
percent Without addition
6,6'-thiobis- (2-ethyl-
resorcinol)
p-propoxyphenol
6,6'-thiobis- (2-ethyl-
resorcinol)
p-propoxyphenol 0
0.05
0.05
0.025 \
0.025 j 100
48
54
20th

Tables 3a, 3b, 4a, 4b show the synergistic effect of the polymerization inhibitor according to the invention. It remains in the presence of iron and iron compounds fully preserved.

Example 4

20 ml of vinyl acetate each, provided with the stabilizing agents listed below, are mixed with 180 mg dilauroyl peroxide brought to boiling temperature in a special flask, whereupon the external heat supply is set. Due to the heat of polymerization that occurs, the mixture begins after one given time to boil again. The time until the samples boil again is a measure of the quality of the polymerization inhibitor.

Table 6 can be seen that when polymerizing styrene with the addition of the invention Mixtures a strong polymerization inhibition occurs.

Example 6

15 g of methyl methacrylate are gelösi together with 100 mg of dibenzoyl peroxide in 90 g of η-hexane and polymerized at 65 ° C for 24 hours. The resulting polymer is filtered off from the η-hexane unc recorded gravimetrically. If the polymer yield is less than 100 weight without the addition of a stabilizer percent assumed, the addition of the following polymerization inhibitors results in fol low yields:

mn zoo / 1 Oi

Table 7

10

Conc yield tration Polymer Polymerization inhibitor (in weight in weight percent percent related to Monomer) 1ΩΟ Without addition O -LVlV / 3,3'-thiobis- (5-t-butyI- 58 6-methyl-hydroquinone) 0.05 49 p-methoxyphenol 0.05 3,3'-thiobis (5-t-butyl- 6-methyl-hydroquinone) 0.025 1 21 p-methoxyphenol 0.025 /

polymerized at 70 ^{° C.} The polymer produced is filtered off from the solvent and weighed after drying. If the polymer yield without stabilizer is assumed to be 100 percent by weight. men, the addition of the following | Polymerization inhibitors the following yields:

Table 8

10 polymerization inhibitor

»5

Table 7 can be seen that when polymerizing methyl methacrylate under Addition of the mixtures according to the invention a strong ao polymerization inhibition occurs.

Without addition

Di-m-cresol monosulfide

p-ethoxyphenol

Di-m-cresol monosulfide
p-ethoxyphenol

concentration

(in percent by weight based on

Monomer)

0.05

0.05

0.025

0.025

Yield of polymer in percent by weight

100 49

53

19th

Example 7 From Table 8, it can be seen that the poly

15 g of 4-vinylpyridine are mixed with 100 mg of dibenzoyl- Ss'S Maßei Ο ^ Γ ^ Tl ' Τ * *? peroxide dissolved in 100 cm = η-hexane und'20 hours * ₅ LmmfnTauirS ^{a strong}

Claims (1)

1 2 can be (German Auslegeschrift 1243172). These mixtures also have the disadvantage that vinyl esters, such as acrylic acid esters or 1. Polymerization inhibitor for polymerizable vinyl acetate, can be cleaved by ammonia,
vinyl group-containing aliphatic, aromatic and 5 Furthermore, mixtures of thiobispnenols and / heterocyclic compounds, labeled or diphenylamines and / or phenazmen with Tetran et by a mixture consisting of Un (French patent 1 557 427) afc Stabilisie- A) 10 to 50 parts by weight of thiobisphenol have been used as the agent, but de = ^ General formula requirements often do not meet the requirements. So both For example, colored poly (HOV _n ^ / v ^ ¹¹ 'mers are obtained as a result of the dye content. It has now a polymerization inhibitor for polymerizable vinyl group-containing aliphatic, aromatic and heterocyclic compounds found to R _{"15 d, it} is characterized by a mixture consisting