DD150618A5 - PROCESS FOR PREPARING VINYL CHLORIDE POLYMERIZES - Google Patents

Abstract

The present invention relates inter alia to a process for the preparation of vinyl chloride polymers by polymerization of the monomer or monomer mixture in aqueous dispersion with free-radical catalysts, optionally suspension stabilizers, emulsifiers and other polymerization auxiliaries, which is characterized in that the polymerization is carried out in a reactor whose Innenwaende and the remaining parts, on which polymer deposits can form, are wholly or partly provided with a coating containing certain compounds of the general formula X. According to the invention, in particular with vinyl chloride copolymers it is possible to achieve a substantial suppression of the formation of polymer deposits.

Description

Berlin, 17. 9. 80

220977 -Ί ~ AP C 07 D / 220 977

GZ 57 243 11

Process for the preparation of vinyl chloride polymers. Field of application of the invention

The invention relates to a process for the preparation of vinyl chloride polymers.

Furthermore, the invention relates to a means for charging Polytnerisationsgefäßen and coated with this agent polymerization vessel *

Characteristic of the known technical solutions

In the preparation of vinyl chloride polymers by polymerization in an aqueous medium formed in the course of polymerization on the inner wall of the polymerization autoclave and the internals Polymerisatbeläge. By these deposits, the polymer yield is reduced and the quality of the product deteriorates because the encrustations fall off partially and get into the final product and there to specks or "fisheyes" lead «The deposits also hinder the removal of heat of polymerization through the reactor walls, which uneconomical, long Reaction times must be accepted.

The removal of such deposits is therefore essential, which usually happens by mechanical means. For this purpose, mostly pressurized water ejection devices are used, but only remove the slightly adhering wall deposits. Therefore, the reactor must be climbed after a few approaches under complex safety precautions and additionally cleaned by hand with a spatula. These cleaning jobs are labor intensive and costly,

ι. L OL! i JU U '' OO <J Ι> Ί JL

α ?. 9. so

AP C 07 D / 220 977 GZ 57 248 11

220377 - L

Long downtimes and thus considerably reduce the economic efficiency of the process «

There has therefore been no lack of attempts to reduce such polymer deposits in the production of vinyl chloride in aqueous dispersion or to avoid the same. However, a satisfactory solution to the problem has not yet been achieved.

Some of the numerous known processes are intended to reduce the formation of deposits by means of process engineering. Examples include: stripping off the walls of the reactor with a correspondingly extended

2 2 0 9 7 7

formed stirrer, the regulation of the wall temperature to at least the temperature of the reaction medium, the cooling of the reactor wall to -15 ° C to 0 ⁰ C, the feeding of aqueous solutions, for example, salts of permanganic acid, chromic acid or dichromic acid during the polymerization at the interface between liquid and gas phase, the polymerization while passing an electric current through the liquid reaction medium, etc

 10

In other known processes, the components of the polymerization recipe are changed and / or further substances are added to the polymerization liquor.

Other known methods use for covering suppression reactors with specially formed or coated inner walls, e.g. those with a roughness depth of the wall of less than 10, together with water-soluble, reducing inorganic salts and certain stirring speeds; or an insoluble wall coating of a crosslinked polymeric material containing polar groups and prepared with an aldehyde crosslinking component; or a wall coating which consists predominantly of polyethyleneimine which has been hardened with a urea, aldehyde or diisocyanate, wherein a divalent tin salt of an inorganic acid may also be added as an inhibitor to the polymerization medium. Furthermore, wall coatings have been described with polyaromatic amines or with specific benzothiazol-2-one-hydrazone derivatives.

To mention here is also the DE-OS 2,044,259, in which the teaching is given u.a. to use organic dyes as antiwear agents. In addition to a large number of other representatives are also mentioned in general oxazine dyes. Concrete representatives of this extensive

17. 9, 80

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However, the rich class of dyes are not disclosed either in the description or in the examples.

Finally, it has already been known from EU-P 0,000,166 to apply dyestuffs with solubilizing groups such as -COOH or SO, H groups as such or as salts from aqueous solution for the purpose of pad suppression onto the reactor walls * in the same patent application For this purpose, water-soluble, ionic dyes are proposed with a heterocyclic ring system.

The previously known for the pad suppression in the vinyl chloride polymerization materials are by no means fully satisfactory. For example, they are not universally applicable, with the result that they can not be used in all common types of PVC, especially those with low molecular weight, or that in some cases only the recipes must be specially tailored to these substances. A number of the active substances must continue to be used in an organic solvent, or it must be because of too low efficiency solutions with a relatively high content of z. B. more than 0.1 % are applied to achieve a satisfactory effect. In addition, many of these substances also · an undesirable retarding effect on the polymerization. (Jm to avoid this drawback, it is necessary to carefully rinsed after the wall treatment with these agents to prevent interference of the polymerization by the excess Antibelagsreagens. A resulting receivable is a high wall affinity of each substance so da2> despite careful Rinsing

17. 9. 80

AP C 07 D / 220 977 GZ 57 248 11

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There is insufficient effectiveness on the wall. Aim of the invention

The aim of the present invention is to provide a process for the production of vinyl chloride polymers, which does not have the disadvantages of the prior aer art and which has advantages over the known methods in the combined analysis of the above points and are used in which in particular belagsverhindernde substances, which have a high and temporally long-lasting scale-preventing effect and are also sufficiently effective in the copolymerization of vinyl chloride.

Loan of the invention

The invention has for its object to find a substance which has a coating-preventing effect and which is suitable for the coating of the reactor walls.

According to the invention, the polymerization is carried out in a reactor whose internal parts and its internals are partially or completely provided with a coating consisting of certain, water-soluble oxazine dyes.

The present invention therefore relates to a process for the preparation of vinyl chloride homopolymers, copolymers or graft polymers which contain at least 50% by weight of polymerized vinyl chloride units by polymerization of the monomer or monomer mixture in aqueous dispersion

17. 9. 80

AP C 07 D / 220 977

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radical-forming catalysts, optionally suspension stabilizers, emulsifiers and other polymerization auxiliaries, characterized in that the polymerization is carried out in a reactor whose inner walls and the remaining parts, on which polymer deposits can form, are wholly or partially provided with a coating, the compounds of the general formula

2 0 9 7 7

contains, in which the individual substituents mean the following:

R ₁ , R p = H; saturated hydrocarbon radical having 1 to 8 C atoms, preferably aliphatic

a hydrocarbon radical with 1 to 6 C atoms;

R-, Rj ,, R [-, Rg = H; saturated hydrocarbon radical with

1 to 8 carbon atoms, preferably aliphatic hydrocarbon radical with 1 to

6 C atoms; OH; O-saturated hydrocarbon radical having 1 to 8 C atoms, preferably O-aliphatic hydrocarbon radical having 1 to 6 C atoms;

15 -N- ^ ^{RI H}

\ _R "; -N-SOp-Aromat, preferably

isocyclic having 6 to 10 C atoms, optionally substituted by radicals such as R ₁ ZRpJ or

Rj and Rg = isocycl. or heterocycl. Aromatic with 6 to 10 C atoms, optionally substi

tuiert with residues such as R ₁ ZRp ';

however, at least one of R ~ to Rg is OH or

\ _R "represents;

R '= H or as R ₁ ZRpJ

R "= H or as R.ZRpj Aromat, preferably

isocyclic with 6 to 10 carbon atoms, optionally substituted by one or more of the following groups corresponding to R..Z

Rpj O-saturated hydrocarbon

rest with 1 to 8 carbon atoms; OH; COOH;

"^H; SO, H; SO,

(R ¹¹¹ , R ^IV = H or C 1 -C 8 R ₇ , R o, R q = H, saturated hydrocarbon radical having 1 to 8 C atoms, preferably aliphatic

220977 -j-

hydrocarbon radical having 1 to C atoms; O-saturated hydrocarbon radical having 1 to 8 C atoms, preferably O-aliphatic hydrocarbon radical having 1 to 6 C atoms.

X = any monovalent anion or a

corresponding Anlon equivalent.

Furthermore, the invention relates to a polymerization vessel, the inner walls and other parts, on which polyacrylate deposits can form, are completely or partially coated with the above coating system.

Another object of the present invention are finally the compounds of the above general formula itself as well as anti-scale substances containing the above compounds.

The anion X ~ is not critical to the efficacy of the substances of the invention and therefore may be of any nature. By way of example, halogens, preferably Cl.sup.- and Br.sup.-, 0H.sup.-, (S0j-) .sup.12 _> N0.sup.-, (POJ.sup.- ₎ .sup.1 _{/ 3} , R.sup.'-COO.sup.-, (R ') = C _1-5 alkyl, aryl), R ^IV -SO ,, (R ^IV = aryl C, _in ), (? ⁰⁰ ) _1/9 * etc.

^ό ° " ^ιυ coo" ^Wd

In the above general formula, preferably: R ₁ , R ₂ = C ₁ -C ₆ AlkYl;

R ₃ = H; OH;

:, or. Rc = -N ^.

R ¹ = H; C _1-6 alkyl such as methyl, ethyl, propyl, butyl, i-butyl;

R "= H; C, / alkyl, aromatic isocyclic

Hydrocarbon radical having 6 to 10 carbon atoms, in particular phenyl or toluoyl given

if substituted by OH, COOH,

or

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\ _H groups; R, - = OH; -N-SOp aromatics (isocycl.) With 6 to

C atoms, in particular phenyl or toluoyl, optionally substituted as in R ".

Ry, Rg, Rg = H.

Preferred representatives are also compounds in which Rp. And Rg are parts of an aromatic (isocyclic or heterocycl.) Ring, preferably a pyridine ring, and R ^ is H, OH or -N < _R1I , with R "in particular phenyl or

Toluoyl and Rj, which means OH group. The N atom in the pyridine ring is preferably such that R ^. begins with its N-atom. 15

Are Rp and R, - not part of a ring, so particularly favorable results are obtained with compounds of the above general formula with

R ₁ , R ₂ = Cj ^ alkyl; R ₃ = H; OH; Rj, = OH; NH ₂ ; -N <^ _R ", with R" in particular phenyl or

toluoyl; R ₅ = H; OH; R, = OH; -N-S0 ₂ ~ aromatic (isocycl.) With 6-10 C atoms,

H optionally substituted as in R ".

A larger number of the compounds according to the invention, which are distinguished by a particularly high wall affinity, have the following common structural principle:

N-S0 ₂ Arorrat

^X ~ ^H X = O or

or

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Some typical representatives of compounds of the above general formula are listed in Table I below.

Table I

formula

substituents

R ₂ = CH ₅ R ₅ = I

2 2 097 7 - »-

Table I (cont.)

formula

substituents

N-CH ₀ -CH ₀ H 2 3

'25

= H

R ₅

*, = N-CH ₀ -CH-

tr Z

x =

K ₃

= CH.

= H

= H

R, =

-R "

R ¹ = R "= X =

! CH. Cl

R. =

= C ₂ H ₅

R ₅ + R. =

R. =

N-CH.

H "

6 = Cl "

OH

1 ^{= R} 2 = c ₂ i Rt - = H> K ₃ = OH , = OH j α ^R 4 = H X> = a

= CH

= H = OH

= a

Cl

= H = OH

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Table I '(cont.)

formula

substituents

R .. - R «- CH. = H

= N-SO; H

^R 5 ^{= 0H} R ₆ -H

X = Cl "

CH.

Cl = R ₂ = C ₂ H ₅ = H

= N-CH ₀ CH-H 2

= H

X = Cl

CH.

(SO ₄ )

NH,

CH:

-Θ = H ^ ₄ = NH ₂

X = (SO) ⁴

" ² 1/2

⁰ S CH ^ ⁺

= 0

R ₃

= H

X = Cl

)H

COOH = H

COOH

-Θ

= Cl

COOH

= R ₂ = H

R = _r :

₀ R- + R, - 3 Th

-Θ

X = Cl

)H

220 97

Table I (cont.)

Formula substituents

OH -J

= H

= CH ₃ R ₅₊ R ₆ = X = Cl "

R. = N - <__ Q __ ^ KXX) HH OH

= CH ₀ ;

= H

X = Cl *

R = N ^<4 H

ti H ¹ S

fa = R, = CH.

= H

N-CH ₃ H

= CH.

MO. = H

R ₅₊ R ₆

 Θ

OH = CH.

= H

R ⁴ = H N

R ₅₊ R ₆

= Θ

X = Cl

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Table I (cont.)

- 1t3> -

·>. _T / + j 0 TJ -ι 1 ι '000 ~ \ K ₃ ^R 4 R ₁ = substituents K ₅ = H H formula ^ C ₂ H ₅ kt N) H -I K ₃ = R ₂ = CH ₃ K ₆ = H cl " • - ί <2 ^ Ν A.0 ' OH ^{v R} ₄ ⁼ OH = / ^ COO \ R ₁ ^{= R} 2 ^: OH χ K ₅ = ^C A \ J. ^ ² ^^ ⁵ ^ ⁵ ^ CCO 'Λ ir \ 1/2 ^R 4 OJ Il Il = C ₂ H ₅ K ₆ = γ - H Oil ·: C ₂ H ₅ ^ T 2 OH Cl " / + 3 ^ o-- cl " 0 = K2 K ₅ = '' ^ NH Ki = H = NH ₉ ^{= C} 2 ^H 5 K ₆ = X = R ₃ OH cl " ^R 4 OH - r cl " , / + OH • "1 = K ₂ K5 = ^3H 5 PH ^ ⁺ K ₃ = H = C ₂ H ₅ K ₆ = OH QI ₃ OH K ₄ = OH X = H > cl " 3 OH Cl  "2 K ₅ = T OH r R ₁ = H = ^ ₃ R ₆ = P = H X = = H CH ₃ j Cl "* ^R ₄   OH Oil/- ci ~ = K2 K ₅ = OH I = H = CH ₃ R, = = OH X = cl " UH Π OH I 6

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Table I (cont.)

Ί5

formula

substituents

C H,

Cl Ki =

= H

^R 4 ⁼

R ₅ = HR ₆ = HX = Cl "

^C 2 ^

OH

Nd

.C ₂ H ₅ * ^C 2 ^H 5

^R 1 ⁼

= CH.

= ^C 9 ^H c = H

R ₄ = nc: ^ri ,

R ₅ =

= H

R ₆ = OH R '= R "= CX = Cl"

2

R ₁ = R ₂ = CH ₃ R ₃ = HR, = OH

4th = Cl " «· 6 = OH X = CH ₃ X = Cl R ₁ = C _A R ₂

CH _x CH ⁺

OH

.N

^ CH ₃ ^ CH ^

= OH

= N

= H

-R "

-R «- CH-, R, - - H

3 ^R 6

R ₃ =

R ₄ = R ₅

= H

R ^f = R "=

4 M / 3

75

= H

From

2 2 0 9 7 7 - * · -

Of course, it is within the scope of the invention to use the substances according to the invention also in mixture with each other.

In addition, it is possible to combine the substances according to the invention with known, coating-suppressing materials, for example compounds having azine or thiazine rings, such as methylene blue, organic dyes, such as nigrosine black or aniline black, inorganic

Pigments as described in DE-OS 2,044,259 or with polymeric imines according to DE-OS 2,357,867 or with polyaromatic amines according to DE-OS 2,541,010 or with benzenethiazol-2-one-hydrazone derivatives according to DE OS 2,703,280 or DE-OS 2,757,924.

Furthermore, the substances according to the invention can be used in combination with halides, hydroxides, oxides and carboxylates of any metallic element according to DE-OS 2,557,788, in particular tin II salts, wherein between the substance according to the invention and

optionally form complexes in situ with the additive. Under certain circumstances, such metal complexes with the substance according to the invention can also be used from the outset, e.g. with copper, silver, zinc,

Tin, molybdenum, iron, cobalt, nickel ions as described in DE-OS 2,548,424.

Finally come as additives including anti-foaming agents, antioxidants, wetting agents udgl

 in question.

The additives described above are used above all when a crosslinking substance or substance mixture is used as the carrier material, since then a particularly effective fixation takes place on the coating surfaces.

2 2 0 9 7 7 - δ -

The term "coating" is generally to be understood as meaning those coatings or films or surface coatings which comprise contacting a solution or dispersion of the substances according to the invention - optionally in combination with other known coating-suppressing substances or corresponding auxiliary substances according to page 14 - with the respective internal parts of the invention Reactor arise, for example by spraying, rinsing udgl. or even those coatings which are obtainable with the concomitant use of a film-forming, preferably crosslinking carrier substance.

The amount of applied substance according to the above general formula is dependent on the type of polymerization, the recipe, the wall condition of the reactor, etc.

suitably more than 0.001 g / m and preferably

ρ more than 0.01 g / m. The upper limit is limited primarily by economic considerations and lies in

2 usually at about 0.1 g / m.

Since the compounds according to the invention are electron-exchangeable and are oxidized by atmospheric oxygen or, for example, peroxidic initiators, the oxidation products are present in the resulting coatings in addition to the actual compound according to the above formula. It can be assumed that the charge transfer complexes (charge transfer complexes) or semiquinone structures that form on the coated surfaces are essential functional units.

The fixation of the compounds according to the above general formula on the reactor parts to be coated can, as already mentioned, be carried out in such a way that an additional film-forming, preferably crosslinking carrier substance is used, as in German Patent Applications P 27 03 280.0 (DE-OS 2,703. 280) and P 27 57 924.4.

Preferably, the compounds of the invention

However, since they have a sufficiently strong wicking power to the corresponding reactor parts, without additional carriers employed, i. the surfaces to be coated are simply treated with a solution or dispersion of these compounds. If necessary, this treatment can be repeated several times after appropriate intermediate drying and possible heating. As a rule, however, a single treatment is sufficient. This treatment is carried out by the usual methods generally at normal temperature, e.g. by rinsing, rinsing, brushing, spraying with rinsing nozzles, udgl. and usually before each polymerization approach. It has proven to be expedient to rinse the treated areas prior to the polymerization with about the same amount of water or polymerization and remove the expired solutions.

Suitable solvents for the compounds according to the invention for preparing the corresponding treatment solutions, besides water, are preferably those solvents which are at least partially soluble (or miscible with) in water, for example lower alcohols such as methanol, ethanol, n (i) -propanol, n (i) butanol; Ether alcohols such as monomethyl glycol ether, ketones such as acetone, esters such as ethyl acetate, butyl acetate; Dimethylformamide, dimethylacetamide, dimethyl sulfoxide, acetonitrile and corresponding mixtures with each other and with water.

Preference is given to using water or mixtures thereof with lower alcohols having 1 to 3 carbon atoms and especially water / methanol mixtures, it being possible for the water content of these mixtures to be greater than 50% by weight, based on the total mixture Solubility - (which of course depends on the nature of the substituents) and the desired concentration. Substances that carry acidic or basic groups may also be added by salt formation

2 2 O 9 7 7 - A3 -

corresponding pH value in aqueous or aqueous / alcoholic solution. Particularly suitable are those compounds which becomes soluble at a pH greater than 7i, preferably between 8 and 10.5. In the strongly acidic range, the effectiveness of the substances is sometimes considerably reduced.

The content of the working solutions of the substance according to the invention can vary within wide limits between about 0.1 mol and 100 mmol / l per liter. Even the highly diluted solutions are less sensitive to oxidation by atmospheric oxygen and do not require a largely anaerobic work. Preference is given to solutions with 1-50 mmol substance / l; These can be handled and used under normal conditions, ie in air.

The treatment solutions used for this process have a pronounced reducing power, especially in the alkaline range. Partially oxidized solutions show no impairment of their effect. The charge-transfer complexes that are likely to contain them can even increase their activity. Therefore, it is not necessary to either prepare the solutions fresh, or to carry out the production and storage under nitrogen protection. The claimed substances may also be in reduced form, e.g. verküpt be used with dithionite or formamidinesulfinic acid, some such solutions are particularly ergibig and increased in their effect

In order to improve the wetting properties of the working solutions, it is advantageous to add to them the same dispersants or wetting agents which are also added to the liquor for the suspension polymerization; Examples of this are in DE-OS 2,703,280 or

35. DE-OS 2,735,770.

2 2037 7 - * -

Each polymerization vessel for the polymerization of. Ethylenically unsaturated compounds can be provided with the coating according to the invention, optionally in non-metal reactors with concomitant use of vehicles (Lakken) for fixation. Thus, the surfaces to be coated may be made of a variety of materials, e.g. of glass, enamel or enamel or metal, preferably steel. The greatest problems with respect to polymer deposition generally occur in steel reactors, so that they are preferably suitable for the coating according to the invention.

In addition to the inner walls of the polymerization reactor also polymer deposits on the so-called internals, such as stirring devices, baffles (baffles), filler neck, valves, pumps, piping, measuring instruments and indoor coolers (heat exchangers) can form, which therefore also completely or partially to coat ^; or to be treated. The same applies to outdoor coolers, provided they are placed more or less directly on the polymerization vessel. If appropriate, it may also be advantageous to add small amounts of the substance of the invention, which suppresses coating, for example 50 to 100 ppm, to the polymerization liquor.

In the process according to the invention for the preparation of vinyl chloride polymerization, the polymerization itself is carried out by customary methods, in which case vinyl chloride homopolymers, graft copolymers or copolymers can be prepared, by the continuous or batchwise process, with or without the use of a seed prepolymer, etc. It may be in aqueous dispersion, ie in emulsion or suspension in the presence of the usual initiators, emulsifiers or suspension stabilizers and optionally further poly- '. merisationshilfsstoffen be polymerized. The poly

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Merisationsverfahren can be carried out under reflux and also in the mode of operation with a filled reactor, in which therefore the reaction vessel is completely filled with the polymerization medium and maintained during the entire polymerization by appropriate post-dosing in this state.

As initiators which are expediently used in amounts of from 0.01 to 3% by weight, preferably 0.1-0.3% by weight, based on monomers, mention may be made, for example:

, Diaryl, diacyl peroxides such as diacetyl, acetylbenzoyl, dilauroyl, dibenzoyl, bis-2,4-dichlorobenzoyl, bis-2-methylbenzoyl peroxide; Diacyl peroxides such as di-tert-butyl peroxide, peresters such as tert-butyl percarbonate; tert-butyl peracetate, tert-butyl peroctoate, tert-butyl perpivalate; Dialkyl peroxide dicarbonates such as diisopropyl, diethylhexyl, dicyclohexyl, diethylcyclohexyl peroxide dicarbonates; mixed anhydrides of organic sulfo acids or organic acids, such as acetylcyclohexylsulfonyl peroxide; as a polymerization known azo compounds, such as Azoisobuttersäurenitril, also persulfates, such as' potassium, sodium or ammonium persulfates, hydrogen peroxide, tert-butyl hydroperoxide, or other water-soluble peroxides, and also corresponding mixtures. In the case of peroxidic catalysts, these may also be used in the presence of from 0.01 to 1% by weight, based on monomers, of one or more reducing substances suitable for the construction of a redox catalyst system, e.g. Sulfites, bisulfites, dithionites, thiosulfates, aldehyde sulfoxylates, e.g. Formaldehydsulfoxylat be used. Optionally, the polymerization may be carried out in the presence of soluble metal salts, for example, copper, silver, iron or chromium, the amount suitably being from 0.05 to 10 ppm (on a metal basis based on monomer).

aa

 2 2 0 9 7 7 - «« -

Further, the polymerization, if conducted by the suspension method, may be in the presence of 0.01 to 1 part by weight, preferably 0.05 to 0.3 part by weight, based on monomers, of one (or more) protective colloid (s), such as polyvinyl alcohol, which optionally contains up to MO mol% acetyl groups, cellulose derivatives, such as water-soluble methylcellulose, carboxymethylcellulose, hydroxyethylcellulose, methylhydroxypropylcellulose, and gelatin, glue, dextran, further copolymers of maleic acid or its half esters and styrenes take place ,

In addition, the polymerization can be carried out in the presence of from 0.01 to 5% by weight , based on monomers, of one or more emulsifiers, wherein the emulsifiers can also be used in admixture with the abovementioned protective colloids. As emulsifiers anionic, amphoteric, cationic and nonionic can be used. Examples of suitable anionic emulsifiers are: alkali metal, alkaline earth metal, ammonium salts of fatty acids, such as lauric, palmitic or stearic acid; of acid fatty alcohol sulfuric acid esters; of paraffin sulphonic acids; Alkylarylsulfonsäuren, such as Dodeqylbenzol- or dibutylnaphthalenesulfonic acid, from Sulfobernsteinsäuredialkylestern, and the alkali metal and ammonium salts of epoxygruppenhaltigen fatty acids, such as epoxy stearic acid; of reaction products of peracids, for example peracetic acid with saturated fatty acids such as oleic acid. As amphoteric or cationic emulsifiers, for example,

.30 suitably: alkylbetaines, such as dodecylbetaine, and alkylpyridinium salts, such as laurylpyridinium hydrochloride; further Alkylamraoniumsalze, such as Oxäthyldodecylammoniumchlorid. Suitable nonionic emulsifiers are, for example: partial fatty acid esters of polyhydric alcohols, such as glycerol monostearate, sorbitol monolaurate, oleate or. palmitate; Polyoxyethylene ether of fatty alcohols or

2 20977 - «t -

aromatic hydroxy compounds; Polyoxyäthylenester of fatty acids and polypropylene oxide-polyethylene oxide condensation products.

In addition to catalysts, optionally protective colloids and / or emulsifiers, the polymerization in the presence of buffer substances, such as alkali metal acetates, borax, alkali metal phosphates, alkali metal carbonates, ammonia or ammonium salts of carboxylic acids and molecular size regulators, such as aliphatic aldehydes having up to 4 carbon atoms, chlorine or Bromocarbons, such as Di- and tri-chloroethylene, chloroform, bromoform, methylene chloride, and mercaptans are performed.

The .Polymerisationstemperatur is usually 30 to 100 ⁰ C, the polymerization 4 to HO atü and the pH 3.5-8.

For example, one or more of the following monomers are suitable for the copolymerization with vinyl chloride: olefins, such as ethylene or propylene; Vinyl esters of straight-chain or branched carboxylic acids having 2 to 20, preferably up to H, carbon atoms, such as vinyl acetate, propionate, butyrate, 1-ethylhexoate, vinylisotridecanoic acid ester; Vinyl halides, such as vinyl fluoride, vinylidene chloride; Vinyl ethers; vinylpyridine; unsaturated acids, such as maleic, fumaric, acrylic, methacrylic acid and their mono- or diesters with mono- or dialcohols having 1 to 10 carbon atoms; Maleic anhydride, maleimide, and their N-substitution products with aromatic, cycloaliphatic and optionally branched, aliphatic substituents; acrylonitrile; Styrene.

For graft copolymerization it is possible, for example, to use elastomeric polymers which are polymerized by

2Λ

2 2097 7 -

tion of one or more of the following monomers: dienes, such as butadiene, cyclopentadiene; Olefins, such as ethylene, propylene; styrene; unsaturated acids, such as acrylic or methacrylic acid, as well as diester esters with mono- or dialcohols of 1 to 10 carbon atoms; acrylonitrile; Vinyl compounds, such as vinyl esters of straight-chain or branched carboxylic acids having 2 to 20, preferably 2 to 4, carbon atoms; Vinyl halides, such as vinyl chloride, vinylidene chloride.

After the polymerization, it is possible to add to the polymers obtained as aqueous dispersion further substances for stabilizing or improving their further processing properties. Subsequently, the dry polymer is recovered by conventional treatment techniques.

The co- or graft copolymers which can be prepared according to the invention contain at least 50% by weight, preferably at least 80% by weight. polymerized vinyl chloride units.

The inventive method is preferably applicable for the polymerization in aqueous suspension with oil-soluble initiators with the addition of at least one protective colloid (suspension stabilizer) and in particular for the production of vinyl chloride homopolymers, as well as for vinyl chloride copolymers having at least 50% by weight, preferably 80 by weight to 99 -.% polymerized vinyl chloride units.

The preparation of the substances according to the invention is carried out by known synthesis routes, wherein in each case the correspondingly substituted starting materials are to be used

 For example, a general synthetic route, such as that described in B. _25_, 1055 IO67, consists of the following reaction sequence:

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and R, - part

Synthetic methods for compounds where there is an aromatic ring are described in J. Am. Soc. 74, 573-586.

If these compounds are used as a covering suppressant, isolation is not absolutely necessary; rather, for example, the resulting solutions may be further processed as such, i. diluted and provided with other additives.

The good coating-suppressing and the low polymerization-inhibiting effect of oxazine derivatives according to the invention is to be regarded as surprising, since a large number of representatives of this class of substances as shown below by comparative experiments - are either ineffective or partially even, have coating-promoting properties and in some cases additionally act as polymerization inhibitors.

Unexpected and surprising is further that there is no reduction in the use of the claimed substances to reduce the formulation grain distribution spectrum of the polymer, so that an often tedious and expensive special adaptation of the polymerization to the coating prevention process is not hotwendig. On the contrary, it has even been found that certain product properties are significantly influenced in a favorable sense when using the compounds according to the invention

2 20 97 7. ^ib

ZFR value characterizing the plasticizer absorption (DIN 53 * Π7, Β1.1).

A further advantage of the present method is in the wide range of applications, even for the problematic product types with low molecular weight.

Because of the high wall affinity of the oxa invention. zind derivatives, these can be used in very low concentrations, which brings advantages over the hitherto known representatives of this class of substances, inter alia because of the consequent lower pollution of the environment and the simpler treatment of the wastewater. It has been found that even concentrations of 0.005 % of active substance in the treatment solution show a useful effect, but in general concentrations of 0.01 % to 0.25 % will be preferred.

Moreover, Bas's process according to the invention makes it possible to carry out many polymerization batches over long periods of time without disturbing deposit formation on the walls and the installations of the reactor. As a result, a constant good heat transfer to the container wall, which is practically not affected by the upper layer, and thus ensures uniform product quality. Time-consuming, capacity-reducing wall cleaning work accounts, as well as the otherwise inevitable frequent opening of the reactor with the associated harmful YInylchlorid emissions. In continuous polymerization, the periods of time until the continuum shuts off can be extended many times over.

A further advantage of the process according to the invention is that it can also be used in older reactors with elevated wall roughness, which promote the formation of deposits particularly strongly, since

17, 9. 80

AP C 07 D / 220 977

GZ 57 248 11

2 2 0 9 7 7 - »-

proper coating the germination of these iVandporen is effectively suppressed. This applies in particular to the use of particularly active complexing agents of the preferred structure with which it is also possible to achieve coatings of particularly high adhesive strength and durability, which show good coating-suppressing action, in particular also in the copolymerization of vinyl chloride.

The compounds of the invention can be used in addition to their use as anti-fouling agents due to their complex-forming properties with advantage in the field of corrosion protection, in electroplating, as depolarizers and serological tests »

From our example

The invention will be described in more detail below with reference to examples.

Examples 1 ~ 2 6 and yerqlei chsver search A to P

I, Herstellun g of erfind unqsgemäßen oxazine perivate

This preparation is explained by the following compound:

cl "

C ₂ H ₅₊

17. 9 · 80

AP C 07 D / 220 977

GZ 57 248 11

Ae8

220977 -

73.64 parts by weight of glacial acetic acid and 5.355 parts by weight of hydrochloric acid, 37.2 wt .-% were given and 7.44 parts by weight of 3-Diathylaminphenol dissolved therein at 20 C. Then, at 15 to 20 ⁰ C with 7.75 parts by weight of NaNO ₂ solution (40%) was nitrosated. Subsequently, 4.9 parts by weight of 3-aminophenol were added and boiled for 30 minutes under reflux. The reaction mixture is allowed to cool to room temperature over about 2 hours.

220977 -

For workup, the batch was added to 80 parts by weight of water, the precipitated product was filtered off with suction, washed with 150 parts by weight of H "0 in portions and dried at 60 ° in vacuo to constant weight. 5

This synthesis is generally applicable to the claimed compounds, only the work-up and deposition of readily soluble compounds e.g. those bearing a carbonyl or sulfo group (comparative experiments) must be made after refluxing for 3 hours in place of water with saline. If the corresponding molar amount of 3-tosylaminoaniline is used instead of 3-aminophenol, the analogous compound is obtained with R / - = N-tosyl.

^H The compounds in which R ₁ - and Rg are part of an aromatic ring, were prepared according to the conditions shown in the above general literature methods.

II · Use in the polymerization process

1. Experimental arrangement

In the exact testing of the products in terms of deposit prevention is to be noted that on the one hand the recipe and driving the VC polymerisation have a strong influence on the degree of deposit formation, so that even small modifications can cause very large changes in the amount of coating. Even if the respective conditions for the individual approaches are kept the same, as far as possible, the absolute amount of the coating can still be subject to considerable fluctuations. Really representative are therefore only averages of a larger number of

2 2.0 9 7 7 - w -

To attempt. The safest method for an exact and comparative testing is therefore to treat absolutely identical and the same pretreated sheets then with the respective substances and then together with the just pretreated, but without the test substance prepared sheets as blanks in a reactor ., and carry out the evaluation after several polymerization runs. The results found are then to be related to the respectively associated blank values. The following procedure was followed in this way.

In a 400 1 V ^ A reactor equipped with an impeller. Stirrer is equipped, a V ^ A-Ma ^ ischette so clamped against the boiler wall, that about 25 pieces of polished test pieces with a size of 200 mm χ 36 mm and a roughing of about 3 / U of boiler-like material on the inside the cuff can be attached. On these test slides to be tested coating prevention systems are applied from their solutions with the specified content of coating inhibitor by brushing. For each series of tests, two test pieces treated without active substance are taken along to determine the blank value.

The test is carried out as follows: After the preparation of 215 liters of Ε-water, which contains 50 g of partially saponified polyvinyl acetate and 40 g of methylhydroxypropylcellulose dissolved as a dispersing agent, the reactor is closed, charged after displacing the air with 115 kg of vinyl chloride and 115 g of di-2 Ä'thylhexylperoxydicarbonat (as a $ 65 solution in. Aliphaten) pressed as an activator.

2 2 O 9 7 7 - * »-,

The reactor is then heated with stirring (150 rpm) to 53 ° C and kept at 53 ° C until the reactor pressure has fallen by 4.0 bar. The polymerization time is about 6 hours. After the end of the reaction, the reaction mixture is cooled, the polymerization reactor demmohomerisiert, emptied, rinsed with water and opened.

The test pieces are examined and re-coated with scale inhibitors. In this way, three approaches are carried out in the reactor. After the three batches, the test slides are separated from the cuff, dried and the weight of the pad of the treated sample platelet area quantized. determined.

The treatment solutions for Examples 1 to 3 and Comparative Experiments A to P are 0.5 $, based on the active substance, and consist of 1 g of test substance, 10 ml of 2N NaOH and 190 ml of deionized water.

The blank value eliminates the test substance.

"The results are listed in the following Table II and given as a test value / blank value It can be seen that many oxazine dyes have virtually no antisoiling effect, according to the comparative experiments B, D, E, F, G, H, I ₁ J. , K, L, M, and 0. Some of them are even significantly worse than the blank value, and Table II also shows that compounds with COOH or S0-H groups are in many cases considerably worse than the analogous compounds without these groups, compare the example pairs: B and C, N and 1, 0 and 2, and P and 3.

2 2097 7 - so -

Table II

Comparison / ers. / Ex.

Formula topping

(Mg)

comment

= Blank value

(without anti-plaque substance) 110 (+ 5%)

Comparative test

11Ϊ / 110

COO comparative experiment

43/110

124/110

Comparative test

Comparative test

Vergleichsversueh

^C 2 ^H 5

NH,

SO, 108/110

Comparative test

220977

Table 2 (cont.)

- 33-

Comparative experiment / example

formula

Coating (mg)

comment

121/110

Comparative test

137/110

OH comparative experiment

123/110

Comparative test

^C 2 ^H 5

^C 2 ^H 5

: N

106/110

Comparative test

^C 2 ^H 5

^C 2 ^H 5

110/110

Comparative test

2 2 097 7 -

Table II (cont.)

Comparative Experiment / Ex.

formula

Covering (ng)

3ermerkung

SO.

109/110

Comparative test

C ₂ H ₅

SO.

^C 2 ^H 5

N-

N ^ \ ^^ 0

'OH 107/110

Comparative test

CH.

64/110

Comparative test

OH

OH

CH

23/110

inventively

COO

95/110

Comparative test

220977 ~

Table 13 (cont.)

Comparison experiment / example - fbrmel - cl " -NH ₂ cl " Coating (mg) comment 2 21/110 he according to the invention ^C 2 ^H 5 OH W VT JL , 3 ^C2 > X NH-CH-CH ₂ -COO " 14/110 erfindungsgeiräß ^C 2 ^H 5 X P 112/110 comparison ² Jn attempt C ₂ H ₅

2 2 0 9 77 - W - 36 -

The treatment solutions for Examples 4 - 26 are 0.1 $, based on active substance, and consist of

0.1 g of test substance in

a) 20 ml of NaOH + 80 ml of Ε-water (for the alkaline setting) with a blank value of 156 or 158,

b) 20 ml 2nHCl + 80 ml Ε-water (for the acidic setting) with a blank value of 148.

c) 20 ml of dimethyl sulfoxide + 80 ml of Ε-water (for the neutral setting) with a blank value of 266.

The results are listed in Table III and as before, with respective blank value as test value / blank value.

220977

Table III

Comparison test / example

Ibrroel topping (mg)

comment

Cl

8/266

inventively

(neutral attitude)

(alkaline setting)

CH,

/

CH.

> H -

OH

13/156

(alkaline • setting)

Oh,

21/156

(alkaline setting)

220977 -

Table III (Ibrts.)

-38-

comparison

try / example

fbrmel coating (mg)

Bemsrkung

Cl 16/156

erfindunqs-

according to (alkaline

Attitude)

22/148

(acidic attitude)

^C 2 ^H 5

28/148

(acidic attitude)

OH

14/156

(alkaline setting)

25/148

(acidic attitude)

30/266

(neutral attitude)

2 20

Label III (ibr.)

- Ββ »- 39 '

Comparative Experiment /

example

Ibrmel Surface (mg)

comment

16/158

according to the invention , (alkaline

Attitude)

20/158

N-CH - CH H ^Z (alkaline setting)

Cl 9/156

(alkaline setting)

CL

18/156

(alkaline setting)

(alkaline setting)

2 2097 7 -

Table III (cont.)

Comparative experiment / example

Ibrniel Belag

comment

19

-N H

COOH 24/158

inventively

(alkaline setting)

20

COOH 13/158

(alkaline setting)

21

R = ^-N-4 H

OH COOH 26/158

(alkaline setting)

22

R = -N

COOH OH 18/158

(alkaline setting)

23

R. =

-N H

17/158

(alkaline setting)

24

v

7/158

(alkaline setting)

25

26

OH

R ₄ = 19/158

31/158

(alkaline setting)

(alkaline setting)

Claims (7)

Invent υngs s prych 1 "Process for the preparation of vinyl chloride homopolymers, co-polymers or graft polymers which comprise at least 50% by weight of polymerized vinyl chloride units by polymerization of the monomer or monomer mixture in aqueous dispersion with free-radical catalysts, optionally suspension stabilizers, emulsifiers and further polymerization auxiliaries, characterized in that the polymerization is carried out in a reactor whose inner walls and whose other parts on which polymer deposits can form are provided completely or partially with a coating, the compounds of general formula aer Rr- "~ contains, in which the individual substituents mean the following: ' ^R R ₃ , R ₄ , R ₅ , = H; saturated hydrocarbon radical with 1 to 8 C atoms, = H; saturated hydrocarbon radical with 1 to 8 C atoms, OH; O of saturated hydrocarbon residue with 1 to Carbon atoms; 17. 9. 80 AP C 07 D / 220 977 GZ 57 248 11 2. The method according to item I _1, characterized in that R ₅ and R _{β form} a pyridine ring and R _{3 is} H, OH, or R ¹ N is R, OH and R ₇ to R _{Q is} H.
R ". 2 2 097 7 - * o - 2 20977- _o " -N-SOO aromatic with 6 to 10 C K ti. Atoms, optionally substituted with radicals such as R./Rp,· or R ₅ and R ₆ = aromatic having 6 to 10 C atoms, optionally substituted by radicals such as R- / R ₂ but where at least one of the radicals R, to & _A ^ OH or -N R 'a H or R, R "= H or as R./R"; aromatic having 6 to 10 carbon atoms, optionally substituted by one or more of the following groups corresponding to R ^ / Ro 'O-saturated hydrocarbon radical having 1 to 8 C atoms, OH, COOH, H H CON, SO ₃ H; SO ₂ N, R ^{111 N} C "(R ¹¹¹ , R ^IV = H or C.-C _r -alkyl) \ _R IV! R ₇ »Rg * Rg = H, saturated hydrocarbon radical having 1 to 8 C atoms, preferably aliphatic hydrocarbon radical having 1 to 6 C atoms; O-saturated hydrocarbon radical having 1 to 8 C atoms, preferably O-aliphatic hydrocarbon radical having 1 to 6 C atoms. X = any monovalent anion or anion equivalent. 17. 9. 80 AP e 07 D / 220 977 G2 57 248 11 3. Method according to item 1 and 2, characterized by
that R ₁ and R _{2 are} C ₄ -alkyl; R ₃ = H or OH; R ₄ = OH, NH ₀ or ^ R * R ₁ . H or OH; R-OH or NHSO ₀ -aromatic 2 ^ S ; 5 ο d with 6 to 10 C atoms, optionally substituted as in R ", and R ₇ to R _{g is} H. 4. The method according to item 1 to 3, characterized in that the coated surfaces are rinsed with water before the polymerization. 5. The method according to item 1, characterized in that in the compounds of general formula R, R ₅ and / or R _{6 is} OH or R ₅ or R _{6 is} NHSO ₂ -aromatic having 6 to 10 C atoms, optionally substituted by radicals such as R- / R ₂ or R ₅ and R _{6 is} arornate having 6 to
10 C atoms, optionally substituted by radicals such as R ", / R ₂ and the remaining radicals have the meaning according to items 1 to 3. 17th 9th ED AP C 07 D / 220 977 GZ 57 248 11 220977 6 «means for coating the internal parts of polymerization vessels to suppress wall covering formation, characterized in that it contains compounds according to point 5. 7, polymerization vessel, characterized in that its inner walls and the other parts, on which polymer deposits can form, are wholly or partially provided with a coating containing compounds of items 1 to 3.