DE10132835A1 - Use of cyanoacetylureas to stabilize antistatic halogen-containing organic plastics - Google Patents

Abstract

The invention relates to cyanogen acetylurea of formula (I), NC-CH2-CO-N(R1)-CO-NH-R2 (I), wherein the radicals R1 and R2 independently represent hydrogen or an unbranched or branched, linear or cyclic alkyl radical having 1 -18 C-atoms or an aryl radical having 6 -18 C-atoms, which can be optionally substituted by one or more alkyl radicals having respectively 1 - 6 C-atoms. According to the invention, said cyanogen acetylureas are suitable for stabilising antistatic organic plastics containing halogen, especially PVC, against thermal and/or photochemical decomposition.

Description

Field of the Invention

The invention relates to the use of cyanoacetylureas for stabilization of antistatically treated halogen-containing organic plastics.

State of the art

Halogen-containing plastics or molding compounds made from them tend known to degradation or decomposition reactions when they are exposed to thermal stress or with high energy radiation, for example Ultraviolet light, come into contact.

To stabilize PVC during processing, metal-containing ones are mostly used Stabilizers based on Pb, Ba, Cd, Sn, Ca and Zn are used. As early as 1940 Urea derivatives such as B. Diphenylthiourea to stabilize PVC proposed (compare: Gächter / Müller, "Plastic Additives", Carl Hanser Verlag 1989, p. 312) These connections are mostly in combination with metal-containing stabilizers used, since they alone are usually not sufficient Long-term stabilization result.

It is also known that plastics, and thus PVC, are pronounced non-conductors are high quality electrical insulators. This property causes a electrical charging of the surface takes place and by the associated Dust attraction quickly contaminates molded parts and makes them unsightly. This disadvantageous properties can largely be prevented by antistatic agents.

A distinction is made between external and internal antistatic agents. External antistatic agents are products that are applied to PVC molded parts as a thin layer on the surface become. The disadvantage of this surface application is the low resistance of the antistatic effect, so that the protective effect wears off over time and above all after rinsing and washing, post-treatment is required. Inner Antistatic agents are part of the PVC compound and are used together with others Additives mixed with PVC. The key benefit of internal antistatic agents is the permanent effect they can achieve.

Solutions as quaternary ammonium salts, amine derivatives and special phosphoric acid ester used. Also hygroscopic substances like Glycerin, glycol and other polyols are suitable. While using the external antistatic is unproblematic, there are several for the internal antistatic Criteria to consider. It is known to the person skilled in the art that the internal antistatic agents The thermostability of PVC compounds deteriorate sharply, with just that antistatic particularly effective quaternary ammonium compounds the strongest Show negative effect, which makes these products as internal antistatic agents for PVC especially hard PVC - are out of the question (see: plastic Manual, Volume 2/1: Polyvinylchloride, Hans K. Felger (Editor), Munich 1985, page 730). The same applies to amine derivatives, such as ethoxylated fatty amines.

Description of the invention

The object of the present invention was to provide substances which can be used for Stabilization of antistatic halogen-containing organic Plastics, especially antistatic PVC, against thermal and / or distinguish photochemical degradation. In particular, these substances be able to improve the thermal stability of using internal antistatic agents, in particular quaternary ammonium compounds and amine derivatives, equipped PVC sure.

The present invention relates to the use of Cyanoacetylureas to stabilize antistatic agents halogenated organic plastics against thermal and / or photochemical degradation.

In one embodiment, the compounds (I) are used to stabilize anti-static PVC against thermal and / or photochemical degradation. The stabilization of internal antistatic agents, especially quaternaries Ammonium compounds and amine derivatives, PVC equipped, especially prefers.

Cyanoacetylureas are substances known to the person skilled in the art and are characterized by the formula (I)

NC-CH ₂ -CO-N (R ¹ ) -CO-NH-R ² (I)

in which the radicals R ¹ and R ² independently of one another each have an unbranched or branched, linear or cyclic alkyl radical having 1 to 18 carbon atoms or an aryl radical having 6 to 18 carbon atoms, which may be one or more alkyl radicals each having 1 to 6 C atoms can be substituted. In the context of the present invention, N, N'-dimethyl-N-cyanoacetylurea is particularly preferred; in this compound, the radicals R ¹ and R ² in the formula (I) each represent a methyl group.

Another subject of the invention are stabilizer compositions for Stabilization of antistatic halogen-containing organic Plastics, especially PVC, against thermal and / or photochemical Degradation, characterized in that these compositions are one or more Contain cyanoacetylureas (I). In one embodiment, the Stabilizer compositions in addition to the compounds (I) one or more Perchlorates.

Perchlorates in the sense of the invention are understood to mean metal salts and ammonium salts of perchloric acid. Examples of perchlorates suitable according to the invention are those of the formula M (C ₁ O ₄ ) _n , where M in particular represents ammonium, Li, Na, K, Mg, Ca, Sr, Zn, Al, La or Ce. The index n corresponds to the valence of the cation M 1, 2 or 3.

The perchlorate salts can with alcohols, such as polyols, cyclodextrins, or Ether alcohols or ester alcohols can be complexed or dissolved therein. To the Ester alcohols also include the polyol partial esters. With multi-value Alcohols or polyols also include their dimers, trimers, oligomers and Polymers in question, such as di-, tri-, tetra- and polyglycols, as well as di-, tri- and Tetrapentaerythritol or polyvinyl alcohol in various degrees of polymerization. in the With regard to perchlorate-alcohol complexes, those skilled in the art are expressly excluded EP-B-394 547, page 3, lines 37 to 56 of known types.

The perchlorate salts can be used in various common dosage forms be, for example, as a salt or solution in water or an organic solvent as such, or mounted on a carrier material such as PVC, calcium silicate, zeolites or hydrotalcite, or incorporated into a hydrotalcite by chemical reaction or another layered grid connection. Are as polyol partial ethers Glycerol monoether and glycerol monothioether preferred.

The perchlorates can be used both individually and in a mixture with one another become.

Another object of the invention is a method for stabilizing antistatic halogen-containing organic plastics, in particular PVC, against thermal and / or photochemical degradation, whereby the Plastics containing in particular internal (internal) antistatic agents, one or more Cyanoacetylureas (I) is added. Preferably, the components, that is antistatic PVC and the compounds (I) in suitable Equipment intimately mixed.

• - als Emulsion oder Dispersion (Eine Möglichkeit ist z. B. die Form einer pastösen Mischung. Ein Vorteil der erfindungsgemäßen Kombination besteht bei dieser Darreichungsform in der Stabilität der Paste.);
• - Als Trockenmischung während des Vermischens von Zusatzkomponenten oder Polymermischungen;
• - durch direktes Zugeben in die Verarbeitungsapparatur (z. B. Kalander, Mischer, Kneter, Extruder und dergleichen) oder
• - als Lösung oder Schmelze.

The stabilizer compositions according to the invention can expediently be incorporated by the following methods:

• - As an emulsion or dispersion (one possibility is, for example, the form of a pasty mixture. An advantage of the combination according to the invention in this dosage form is the stability of the paste.);
• - As a dry mix during the mixing of additional components or polymer mixtures;
• - by adding directly to the processing apparatus (e.g. calender, mixer, kneader, extruder and the like) or
• - as a solution or melt.

Another object of the invention is a stabilized PVC, the one hand Content of one or more antistatic agents, in particular internal (internal) antistatic agents, and on the other hand contains one or more of the compounds (I). On such stabilized and antistatic PVC can be known Be manufactured in a way that is known per se Devices such as the above processing equipment the compounds (I) or a stabilizer combination according to the invention and antistatic agents and if desired, other conventional plastic additives mixed with PVC. In a preferred embodiment, the PVC additionally contains or several perchlorates.

The stabilized PVC containing antistatic agents preferably contains the compounds (I) in an amount of 0.01 to 2.0 phr and in particular 0.01 to 0.5 phr. The one The term phr ("parts per hundred resin") familiar to a person in the art indicates how many Parts by weight of the component in PVC - based on 100 parts by weight of PVC - available.

The stabilized PVC containing antistatic agents preferably contains the perchlorates in one Amount of 0.01 to 2.0 phr and in particular 0.01 to 0.5 phr.

The PVC stabilized according to the present invention can in known ways in the desired shape can be brought. Such methods are, for example, Calendering, extruding, injection molding, sintering or spinning, and also extrusion Blowing or processing using the plastisol process.

Plastisol processing, extrusion and calendering are processes for this Processing of the PVC stabilized according to the invention is particularly preferred.

The PVC stabilized according to the invention is suitable for hard, semi-hard and soft Recipes.

Halogenated organic plastics

In the case of the antistatic halogen-containing organic plastics that it with the compounds (I) or the compositions according to the invention stabilize applies, it is in particular chlorine-containing polymers or their Recyclates. Examples of such chlorine-containing polymers to be stabilized or their Recyclates are: polymers of vinyl chloride, containing vinyl resins Vinyl chloride units in their structure, such as copolymers of vinyl chloride and Vinyl esters of aliphatic acids, especially vinyl acetate, copolymers of Vinyl chloride with esters of acrylic and methacrylic acid and with acrylonitrile, Copolymers of vinyl chloride with diene compounds and unsaturated Dicarboxylic acids or their anhydrides, such as copolymers of vinyl chloride Diethyl maleate, diethyl fumarate or maleic anhydride, post-chlorinated polymers and Copolymers of vinyl chloride, copolymers of vinyl chloride and vinylidene chloride with unsaturated aldehydes, ketones and others such as acrolein, crotonaldehyde, Vinyl methyl ketone, vinyl methyl ether, vinyl isobutyl ether and the like; Polymers of Vinylidene chloride and copolymers thereof with vinyl chloride and others polymerizable compounds; Polymers of vinyl chloroacetate and dichlorodivinyl; chlorinated polymers of vinyl acetate, chlorinated polymeric Esters of acrylic acid and alpha-substituted acrylic acid; Polymers of chlorinated Styrenes, for example dichlorostyrene; chlorinated polymers of ethylene; Polymers and post-chlorinated polymers of chlorobutadiene and their copolymers with vinyl chloride; and mixtures of the polymers mentioned among themselves or with others polymerizable compounds.

Also included are the graft polymers of PVC with EVA, ABS and MBS. Preferred substrates are also mixtures of the homo- and Copolymers, especially vinyl chloride homopolymers, with others thermoplastic and / or elastomeric polymers, especially blends with ABS, MBS, NBR, SAN, EVA, CPE, MBAS, PMA, PMMA, EPDM and polylactones.

Further preferred are suspension and bulk polymers, as well Emulsion polymers.

Polyvinyl chloride is particularly preferred as the chlorine-containing polymer, in particular Suspension polymer and bulk polymer.

In the context of this invention, copolymers or Graft polymers of PVC with polymerizable compounds such as acrylonitrile, To understand vinyl acetate or ABS, where it is suspension, bulk or Emulsion polymers can act. PVC homopolymer is also preferred in Combination with polyacrylates.

Recyclates of chlorine-containing polymers can also be used, although they are this is the polymers described in more detail above, which by Processing, use or storage have been damaged. Especially PVC recyclate is preferred. Small amounts of can also be found in the recyclates Foreign substances may be contained, such as. B. paper, pigments, adhesives, which are often difficult are to be removed. These foreign substances can also come from contact with various Substances originate during use or processing, such as. B. Fuel residues, paint components, metal traces and initiator residues.

Examples About the substances used

Norvinyl S 6260 = S-PVC (K-value = 62 from Hydro Polymers AB)

Vestolith E 6007 = E-PVC (K value = 60 from Degussa)

Vestinol AH = dioctyl phthalate (from BASF)

Kronoss 2220 = titanium dioxide (Kronos Titan)

PEG 200 monolaurate (Cognis / DE)

N, N'-dimethyl-N-cyanoacetylurea (commercial product)

Examples 1 and 2

On the one hand, the individual formulation components were shown in Table 1 below of the examined test recipes, on the other hand the determined test results shown. In the first line of the table are the respective numbers of the examples specified. The proportions of the individual components are given in phr; phr means "part per hundred resin" and indicates how many parts by weight of the respective component after adding the composition in PVC - based on 100 parts by weight of PVC are present. Accordingly, the recipes contain 100 parts of PVC each (sum of Norvinyl S 6260 and Vestolith E 6007).

Example 2 is according to the invention. Example 1 is for comparison.

• - Stabilitätstest bei thermischer Belastung: Entsprechend den Rezepturen wurden Walzfelle hergestellt und die statische Thermostabilität bei 170°C bestimmt. Die Herstellung der Walzfelle erfolgte, indem man die PVC-Pulvermischung und die genannten Rezepturkomponenten auf einem Laborwalzwerk 5 Minuten lang bei 170°C homogenisierte und plastifizierte. Aus den so hergestellten etwa 0,5 mm dicken Walzfellen wurden Teststücke (Prüfkörper) der Größe von 17 × 17 mm herausgeschnitten. Die Prüfkörper wurden bei 170°C im Wärmeschrank auf Glasplatten auf rotierenden Horden plaziert und in 15minütigen Abständen wieder entnommen, bis alle Proben "verbrannt" waren (d. h. Schwarzfärbung erreicht hatten)
• - Farbmessung am Walzfell: Darüber hinaus wurde bei den Walzfellen zur weiteren Charakterisierung die dem Fachmann bekannte L*,a*,b*-Methode (vergleiche DIN 6174) herangezogen. Der L-Wert gibt dabei die Helligkeit an. Bei den Messungen kam ein handelsübliches Gerät mit der Bezeichnung "Micro Color" (Firma Dr. Lange) zum Einsatz.

Tabelle 1

The following measurements were carried out - partially or completely - for the test recipes:

• - Stability test under thermal stress: Rolled skins were produced in accordance with the recipes and the static thermal stability at 170 ° C was determined. The rolled skins were produced by homogenizing and plasticizing the PVC powder mixture and the recipe components mentioned on a laboratory rolling mill at 170 ° C. for 5 minutes. Test pieces (test specimens) measuring 17 × 17 mm were cut out from the approximately 0.5 mm thick rolled skins thus produced. The test specimens were placed on glass plates on rotating trays at 170 ° C. in a warming cabinet and removed again at 15-minute intervals until all samples had “burned” (ie had turned black)
• - Color measurement on the rolled skin: In addition, the L *, a *, b * method known to the person skilled in the art (see DIN 6174) was used for further characterization. The L value indicates the brightness. A commercially available device called "Micro Color" (from Dr. Lange) was used for the measurements.

Table 1

Claims (10)

1. Use of cyanoacetylureas (I),

NC-CH ₂ -CO-N (R ¹ ) -CO-NH-R ² (I)

wherein the radicals R ¹ and R ² independently of one another are each hydrogen or an unbranched or branched, linear or cyclic alkyl radical having 1 to 18 carbon atoms or an aryl radical having 6 to 18 carbon atoms, which is optionally substituted by one or more alkyl radicals each having 1 can be substituted up to 6 carbon atoms,
for stabilizing antistatic halogen-containing organic plastics against thermal and / or photochemical degradation. 2. Use according to claim 1, wherein the compound (I) is N, N'-dimethyl-N- selects cyanoacetylurea. 3. Use according to claim 1 or 2, wherein it is the halogen-containing organic plastic is PVC. 4. Use according to one of claims 1 to 3, the halogen-containing organic plastic is equipped with an internal antistatic. 5. Stabilizer compositions for stabilizing antistatic halogen-containing organic plastics against thermal and / or photochemical degradation, characterized in that these compositions contain one or more cyanoacetylureas (I)

NC-CH ₂ -CO-N (R ¹ ) -CO-NH-R ² (I)

in which the radicals R ¹ and R ² independently of one another each have an unbranched or branched, linear or cyclic alkyl radical having 1 to 18 carbon atoms or an aryl radical having 6 to 18 carbon atoms, which may be one or more alkyl radicals each having 1 to 6 C atoms can be substituted mean
contain. 6. Compositions according to claim 5, wherein the compositions in addition to the Compounds (I) contain one or more perchlorates. 7. A method for stabilizing antistatic halogen-containing organic plastics against thermal and / or photochemical degradation, characterized in that these plastics have a stabilizer composition containing one or more cyanoacetylureas (I)

NC-CH ₂ -CO-N (R ¹ ) -CO-NH-R ² (I)

in which the radicals R ¹ and R ² independently of one another each have an unbranched or branched, linear or cyclic alkyl radical having 1 to 18 carbon atoms or an aryl radical having 6 to 18 carbon atoms, which may be one or more alkyl radicals each having 1 to 6 C atoms can be substituted mean
adds and the components are intimately mixed. 8. Stabilized PVC which on the one hand contains one or more antistatic agents and on the other hand contains one or more cyanoacetylureas (I)

NC-CH ₂ -CO-N (R ¹ ) -CO-NH-R ² (I)

in which the radicals R ¹ and R ² independently of one another each have an unbranched or branched, linear or cyclic alkyl radical having 1 to 18 carbon atoms or an aryl radical having 6 to 18 carbon atoms, which may be one or more alkyl radicals each having 1 to 6 C atoms can be substituted. 9. Stabilized PVC according to claim 8, wherein the antistatic is a internal antistatic. 10. Stabilized PVC according to claim 9, wherein the PVC additionally contains a or more perchlorates.