DED0012276MA - - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY

Registration date: May 15, 1952. Advertised on November 8, 1956

GERMAN PATENT OFFICE

The invention relates to stabilizers for vinylidene chloride-containing copolymers to counteract them to protect the corrosive effects of light.

Copolymers containing vinylidene chloride can be softened with the application of heat and pressure and in forms are processed into articles of daily use, while others are made into fibers or through nozzles Threads can be compressed. In most cases, these articles or fibers and the like are subject to damage. some decomposition when exposed to light for long periods of time, and in particular when the light contains large amounts of ultraviolet rays. With this decomposition goes a progressive darkening of the color of the mass is accompanied, whereby its appearance changes with prolonged exposure to radiation can change from practically colorless to dark brown. However, this change is for that Use of the articles made from the above polymerized materials is very disadvantageous.

It is therefore important to find stabilizers through which this darkening, the vinylidene chloride-containing copolymers are subject to prevention when exposed to light or at least is reduced. Such stabilizers should also be used with the copolymer be perfectly tolerable if they are in a

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Amount to be added as required to achieve the protective effect against the influence of light is.

Proposals have also been made to use various compounds, including nitrogen-containing compounds, to be used for these purposes, but these compounds stabilize the vinyl chloride resp. Vinylidene chloride-containing resins against discoloration not to the desired extent or for the desired Duration.

It has now been found that sufficient protection against the harmful effects of light can be achieved if the vinylidene chloride-containing copolymer is a fluorenonazine as a stabilizer is incorporated that of the general formula

CH

CH

HC
HC

C. C.

C. C.

CH
CH

CH

CH

N-

R ¹ - C - R ²

corresponds to, in which R ¹ represents a substituted or unsubstituted hydrocarbon radical and R ² represents a hydrogen atom or a substituted or unsubstituted hydrocarbon radical or R ¹ and R ² together to form part of a cyclic radical. In the latter case, the stabilizers used according to the invention correspond to the following formula:

CH CH

CH C

CH

CH C-

CH

CH

CH

Ri _ C - R ²

in which Z represents the atoms which together with R ¹ and R ^{2 form} a cyclic radical.

Examples of compounds which fall under the structural ^{formulas above are compounds in which R 1 is} an alkyl group, such as methyl, ethyl, propyl, butyl, amyl or hexyl, or an aryl radical, such as phenyl or naphthyl, which is also replaced by one or more of the the following substituents, such as chlorine atoms, methyl, nitro or hydroxyl groups, can be substituted, while R ^{2 is} a hydrogen atom or a

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Is methyl group, as well as compounds in which R ¹ and R ² together with the carbon atom to which they are connected form a cyclic radical. In cases in which R ^{2 is} a methyl radical, R ^{1 should} preferably be an aromatic radical, examples of such compounds are butyralfluorenonazine (R ¹ = propyl radical, R ² = hydrogen), benzalfluorenonazine (R ¹ = phenyl radical, R ² = hydrogen) ,, o-chlorobenzalfluorenonazine (R ¹ = o-chlorophenyl radical, R ² = hydrogen), salicylalfluorenonazine (R ³ ^ = SaIiCyLTeSt, R ² == hydrogen), i-naphthalfluorenonazine (R ¹ = naphthyl radical, R ² = hydrogen), 2 -0xy-i-naphthalfluorenonazine (R ¹ = 2-oxynaphthyl, R ² = hydrogen), a-methylbenzalfluorenonazine (R ¹ = phenyl radical, R ² = methyl), cyclohexanonfluorenonazine (R ¹ , R ² and the carbon atom connecting them together form one Cyclohexylidene radical), fluorenonazine (R ¹ , R ² and the carbon atom connecting them together form a fluorenylidene radical).

Fluorenonazine can be prepared directly by the action of fluorenone on hydrazine in the presence of an acidic catalyst. The mixed azines used according to the invention can be prepared by reaction between the corresponding aldehyde or ketone and fluorenone hydrazone, the latter compound being obtained by the action of hydrazine hydrate on fluorenone. For example, salicylaldehyde can be reacted with fluorenone hydrazone, whereby salicylalfluorenone azine is obtained, while the conversion of acetophenone with fluorenone hydrazone gives α-methylbenzalfluorenone azine. These condensations are expediently carried out in a common solvent for both reaction units, such as ethyl alcohol or butyl alcohol. The reaction product usually separates out of the reaction mixture in crystal form on cooling and can, if necessary, be purified by recrystallization. The fluorenonazines used according to the invention form crystals, the color of which varies from yellow to dark red. Threads and films made from copolymers containing vinylidene chloride. and such azine-containing compositions are obtained, therefore vary in their color from yellow to deep orange, depending on the azine chosen and its concentration. The use of the azines mentioned is therefore not recommended for the production of particularly light-colored objects. However, it has been found that to achieve sufficient resistance to the damaging effects of sunlight or ultraviolet rays, the amount of azine stabilizer to be used is not decisive and that amounts from 0.05 to TO ⁰ J ₀ and preferably from 0.05 to 3 ° / ₀ calculated on the weight of the polymer or interpolymer, give satisfactory results. Some of the azines of the invention also give in much lower concentrations than those commonly used with other types of stabilizers. adequate protection against decomposition caused by light. For example, must Phenylsalicylsäureester to be effective, are / _{0 is} used in a concentration of 2 ° to 5 °, while

D 12276 IVb / 39b

is used when using Fluorenonazin a high level of protection even at concentrations of o, i to 0.5 ° / ₀ calculated on the weight of the vinylidene chloride interpolymer obtained.

The fluorenonazines can be mixed with the vinylidene chloride-containing copolymer in any way will. So z. B. the stabilizer in a volatile organic solvent such as acetone or Benzene, dissolved, the solution with the powdery copolymer in a suitable mixer mixed well and the solvent removed from the resulting mass by drying. When the vinylidene chloride-containing copolymer can be dissolved in an organic solvent, can the stabilizer is added to the solution mentioned and a homogeneous mixture is produced, whereupon the stabilized mass is obtained by evaporation. It can also be a solution of the fluorenonazine in one water-miscible organic solvents, such as ethyl alcohol, acetone or dioxane, slowly under Stirring an aqueous dispersion of the finely comminuted copolymer containing vinylidene chloride added, the resulting uniform polymeric mass by filtration or in another suitable manner deposited and then dried. According to a further embodiment, the stabilizer in Powder form with the finely ground copolymer by mechanical means, such as grinding in a ball mill.

It does not matter in what way the inventive Stabilizers are added to the vinylidene chloride-containing copolymer; in any case are the masses obtained against sunlight or light with a high proportion of ultraviolet Very constant rays. While such an untreated thread or film made of a vinylidene chloride Copolymer, if exposed to light or ultraviolet radiation, a dark

CH

CH C. C.
H CH CH C. - Il
, C
' \ CH CH CH ^x c ^/ N 1

Assume brown color, a mass that withstands a relatively small amount of any of the new Contains stabilizers, under the same conditions of discoloration for a very long time.

The stabilizers can be any copolymer containing vinylidene chloride, e.g. B. copolymers of vinylidene chloride with monomers such as vinyl chloride, methyl acrylate, ethyl acrylate, Methyl acrylic acid, ethyl methyl acrylic ester, dimethyl maleic acid, diethyl maleic acid, Dimethyl fumarate, diethyl fumarate, vinyl acetate, acrylonitrile, incorporated will. The masses to which the stabilizers are added can also contain plasticizers, Lubricants, pigments, dyes and similar substances that facilitate processing of the masses or used for coloring the objects made from them. Also can other known heat or light stabilizers can also be used.

The vinylidene chloride-containing copolymer should not contain more than 95% vinylidene chloride, expediently 70 to 90% vinylidene chloride.

The invention is illustrated by the following examples. The percentages given are if nothing else is indicated, percentages by weight.

90 Example 1

Of a mixture which consisted of 85% monomer is a vinylidene chloride and 15 ° / ₀ vinyl chloride, an approximately I2 ° / _O vinyl chloride units-containing copolymer was prepared and, a'-Diphenyldiäthyläther as a plasticizer to a uniform mass processes the finely powdered copolymer with 8 weight percent of a. With the addition of fluorenonazine, the following composition was obtained from this copolymer with a plasticizer:

CH

CH

CH

CH

CH

CH C C CH

CH CH

Masses made that are 0.05, 0.1, 0.3 and 0.5 percent by weight of the stabilizer. The first two masses were made by dissolving the stabilizer in Acetone, mixing the acetone solution with the copolymer and evaporating the acetone. The latter two masses were produced by mixing the finely powdered fluorenonazine with the powdered, plastinated copolymer in a spherical

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mill were wed; this procedure was used because the fluorenone azine has only limited solubility in acetone and other volatile solvents. The resulting compositions were transferred into press-.stücke and pressed out of a small ram extruder through an orifice of 0.75 mm diameter, with the barrel of the extruder was heated to 170 to 175 ^0th The threads thus obtained were then drawn out by hand to such an extent that their diameter was reduced to 0.2 to 0.25 mm. The resulting filaments were then wound onto molds and exposed to the light of a charcoal arc in a fadeometer: the time it took each sample to reach about the same degree of decomposition as visually judged by the depth of the brown color developed , was considered to be the relative stabilizing effect of each azine concentration. A control experiment with a thread which had been produced in the same way from the plasticized copolymer, but without a stabilizer, was carried out in the

Exam included. Table 1 shows the test results :

Table 1

Time of exposure to educate ment of a particular, as ° / ₀ fluorenonazine Standard used decomposer degree of efficiency (in hours) O 50 0.05 164 0.10 530 0.30 930 0.50 930

Example 2

In the . Mixed azines listed in Table 2 were obtained by condensation of fluorenone hydrazine made with the corresponding aldehydes. Their melting points, analytical values and colors are also stated there.

Table 2

Fluorenonazine

Butyral

Salicylal

o-chlorobenzal- ..
p-nitrobenzal- ..

i-naphthalene

2-0xy-i-naphthal-

Melting point

43 to 44 ° 132 to 133 ⁰ 150 to 151 ⁰ 184 to 185 ⁰ 139 to 140 ° 200 to 201 °

Nitrogen content ° / ₀ calculated Fcirfoe found II.3 11.1 9.4 orange 9.1 8.8 yellow 9.0 12.8 Orange red 12.3 8.4 orange 8.4 8.0 orange 8.4 Brick red

Benzalfluorenonazine is in the Journ. Amer. Chem. Soc. (1932), p. 3636. It has the Melting point 91 to 92 ° and forms orange-colored plates.

From the plasticized copolymer described in Example 1 with 2% of each of the above Azines were prepared by taking samples of the copolymers with acetone solutions of the required masses Amount of azine mixed and the acetone evaporated. These masses became threads and exposed to light in the fadeometer described in Example 1. The time that at Each sample was required to achieve the specified degree of decomposition is shown in Table 3 evident.

Table 3

stabilizer

Butyralfmorenonazine

Salicylalfluorenonazine

Benzalfluorenonazine

o-chlorobenzalfluorenonazine. .
p-nitrobenzalfluorenonazine. .
i-naphthalfluorenonazine ....
2-Oxy-i-naphthalfluorenonazine
Control (empty)

Exposure time

until the set

Degree of decomposition

(Hours)

610 750 310 280 280 280 280 50

Example 3

Acetophenone and fluorenone hydrazone were reacted with one another in butyl alcohol solution i and the resulting Acetophenonfluorenonazine recrystallized from low-boiling petroleum for purification, orange-colored plates having a melting point of 122 to 123 ° were obtained.

Nitrogen content: found 9.1%, calculated 9.4% · i ° 5 The formula of acetophenone fluorenonazine is:

CH
· / \ c CH \ ■ /
CH // \
cn c C. Il
CH C f TT ^ /
CH . (
// Ά :H -c CH ₃ - ^x c N N
π Il
-C

Cyclohexanone and fluorenone hydrazone were dissolved in light petroleum (boiling point 80 to 100 °) and mixed with one another implemented, being cyclohexanonfluorenonazine

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D 12276 IVb / 39 b

as yellow prisms with a melting point of 80 to 80 ° were obtained. Nitrogen: found io, i% (calculated 10.2%).

From the plasticized copolymer of vinylidene chloride and vinyl chloride described in Example 1 and 2% acetophenonfluorenonazine or cyclohexanonfluorenonazine were mass produced, these are deformed into threads and exposed in a fadeometer to the light of a charcoal arc, as is the case in Examples 1 and 2 has been described. The sample containing acetophenone fluorenone azine resisted 340 hours of extensive discoloration, and the one that Cyclohexanonfluorenonazin contained, 530 hours. This represents a significant improvement over the control sample, the contained no stabilizer and which showed significant discoloration in 50 hours.

Example 4

A mixture comprising 85 parts by weight of vinylidine chloride, 15 parts by weight of vinyl chloride, 2 parts by weight of diethyl maleate and 7.6 parts by weight of dimethyl phthalate, was in aqueous dispersion polymerized, a finely divided, ternary copolymer uniformly mixed with the plasticizer was won. The yield of the copolymer was 83%, so that the content of dimethyl phthalate in the mixture corresponded to 8.9% of the copolymer. By thoroughly marrying the plasticized copolymer with different amounts of fluorenonazine in a ball mill Mass produced. The stabilized masses were shaped into threads in an extrusion press and their light resistance tested as in example 1. A control sample, which did not contain any stabilizing agent, was also exposed. The results are shown in Table 4.

Table 4

"J ₀ fluorenonazine

0.1

0.2

o, 3

Exposure time until. specified degree of decomposition (Hours)

50 960 1470 more than 1600

Example 5

One 85 parts by weight of vinylidene chloride, 15 parts by weight of vinyl chloride, 2 parts by weight of vinyl acetate and 7.5 parts by weight of dimethyl phthalate-containing mixture was polymerized in an aqueous dispersion, a finely divided, ternary copolymer uniformly mixed with the plasticizer is obtained would. The yield of the copolymer was 80 parts by weight, so that the content of dimethyl phthalate in mass corresponded to 9.4% of the copolymer. The plasticized copolymer was mixed with 0.1 weight percent fluorenonazine in a ball mill. The stabilized mass was deformed into threads and their light resistance, as described in Example 1, tested. The time that the The amount of thread needed to achieve the degree of decomposition was 480 hours while a similar thread without fluorenonazine had already decomposed after 45 hours of exposure.

Example 6

The process described in Example 2 was repeated, instead of the copolymer used there, a copolymer was used which had been prepared from a monomeric mixture consisting of 90% vinylidene chloride and 10% vinyl chloride. This copolymer was finely pulverized and then processed into a uniform mass with 8 percent by weight of α, α'-diphenyl diethyl ether as a plasticizer. The results obtained were essentially the same as in Example 2.

The method described in the above examples can be repeated, with the method used there instead Copolymers other copolymers of vinylidene chloride and vinyl chloride are used, which contain at least 70% vinylidene chloride, or copolymers of vinylidene chloride with others Monomers, such as methyl acrylate, ethyl acrylate, methyl methacrylate, ethyl methyl acrylate, Dimethyl maleate, dimethyl fumarate, diethyl fumarate, vinyl acetate, acrylonitrile and the like, which contain at least 70% vinylidene chloride. The results obtained are essentially the same as in the examples above.

Claims (2)

Patent claims: i. Method of stabilizing from 10 to 95% vinylidene chloride existing copolymers against the action of light, marked through the use of fluorenonazine compounds of the following general formula: XH / \
CH C CH C CH CH CH CH CH N. Ri-CR ² in which R ^{1 is} a substituted or unsubstituted, aliphatic or aromatic hydrocarbon radical and R ^{2 is} hydrogen or an aliphatic 609 706/417 D 12276 IVb 139b or R ¹ and R ² together form a part of a cyclic radical. 2. The method according to claim i, characterized in that the fluorenonazm is used in an amount of 0.05 to 10%, preferably from 0.05 to 3 ° / ₀ , calculated on the weight of the copolymer. Considered publications: German Patent Specifications No. 701 837, 734524; U.S. Patent Nos. 2,367,483, 2,396,557. © 609 706/417 10.56