DD254739A1 - STABILIZERS FOR LOW-MOLECULAR AND HIGH-POLYMERIC ORGANIC MATERIALS - Google Patents

Abstract

The aim is to increase the stability of organic materials in their use. The aim is to use stabilizers with high efficacy, very good compatibility and high migration stability. According to the invention, photostabilizers prepared by reacting cyclic multinuclear methylphenol compounds called calix (n) arenes with hydroperoxides are used. The stabilizers are added during processing or during the production of molding materials in a concentration of 0.01 to 1.0 wt .-%, based on the amount of substrate, and are particularly suitable for the stabilization of polyolefins and olefin copolymers, ABS, polyamides, polyesters and liquid hydrocarbons.

Description

Field of application of the invention

The invention relates to stabilizers which protect low molecular weight and high polymer organic materials by addition in small amounts against the photo-oxidative degradation.

Characteristic of the known state of the art

It is known that low molecular weight and high polymer organic materials are protected by stabilizers against photooxidative degradation.

It is known that multinuclear cresol formaldehyde condensates (US Patent 3,149,181, D.A. Akhmedzade, V.D. Jasnopolskii, A.S.Zakhavyan, Z.K. Suleinamova, Azerb.Khim., Zh. 1966 [4] 10-15) have a photoprotective effect in polymers.

Cyclic multinuclear methylphenol compounds, called calix (n) arenes (CD, Gutsche, Topics Curr. Chem. 123, [1984] 1), provide in a complex multistage process UV absorbers with the known structural element of 2-hydroxybenzophenone (see formula). These compounds act as UV stabilizers in PVC (A. Ninagawe, K. Cho,

H. Matsuda, Macromol. Chem., Macromol. Chem. And Physics 186 [1985] 7,1379-1385, Amer. Chem. Soc., Div. of Polym. Chem., Polym. Preprints 24 [1983] 207-208).

R = ύη-r, ü η, i: i - 4,6,8

An essential disadvantage of these compounds is that an expensive multistage process is necessary for their preparation and that the highly toxic chromium (VI) oxide is used.

The use of partially oxidized phenolic resins which have free O-positions in the molecule as Lichtstabilisatdren for transparent coatings based on acrylates and methacrylates has been described (DE-PS 2361 040).

The stabilizers described are used alone and in combination with other known additives, for. As light stabilizer other structure, thermo-oxidative stabilizers, lubricants used.

Object of the invention

Under the influence of light, especially those with high UV content, in the presence of atmospheric oxygen, low molecular weight and high polymer organic materials lose their desired property profile due to photooxidative aging.

The aim of the invention is to improve the photooxidative stability of low molecular weight and high polymer materials by additives which are accessible by simple syntheses of cheap raw materials.

Explanation of the essence of the invention

The object of the invention is to develop new substances based on cyclic Mehrkemmethylenphenolverbindungen - called calix (s) arene - which cause an increase in the photooxidative stability of low molecular weight and high polymer materials.

This object is achieved by stabilizers for low molecular weight and high polymer organic materials - especially polyolefins and olefin copolymers, ABS, polyamides and polyesters - against the degradation by photooxidation, according to the invention compounds by reacting substituted calix (n) arenes of the general formula

in which η = 3 to 8 and R = hydrogen, alkyl, cycloalkyl, aralkyl or aryl radical, with hydroperoxides R'OOH, where R '= hydrogen, alkyl or arylalkyl radical, or with organic or with inorganic Peracids are produced, are used as light stabilizers, optionally in combination with additives known light stabilizers other classes with additions of known light stabilizers other classes and antioxidants.

Advantageously, compounds are used as light stabilizers which have been prepared by reacting calix (n) arenes with hydrogen peroxide, tert-butyl hydroperoxide, cumyl hydroperoxide or tetralin hydroperoxide. The compounds obtained can also be used in combination with other known stabilizers or plasticizers such as quenchers, complexing agents, lubricants, UV absorbers and antistatic agents.

The reaction compounds are advantageously in a concentration of 0.01 to 1.0Ma .-%, in particular from 0.1 to 0.5 Ma .-%, based on the amount of substrate, and the known additives in a concentration of 0.01 to 0.6 wt .-%, in particular 0.05 to 0.3 wt .-%, based on the amount of substrate used.

Surprisingly, the reaction products of calix (n) arenes with hydroperoxides and peracids have a very good light protection effect on polyolefins, olefin copolymers, polystyrene, ABS, PVC, polyamides and polyesters.

Compared to the starting point (s) arenes, the reaction products are characterized by a low melting point, better solubility and compatibility in high polymer materials and thus by improved effectiveness. These compounds have good migration stability due to their molecular size. The use of the compounds increases the utility of stabilized products by significantly extending the life. The incorporation of the light stabilizers takes place in the post-processing extruder, possibly together with other plastic additives, wherein the best distribution of the excipient is achieved by a twin-screw extruder. Also, incorporation in the form of batch or in the processing phase to the molding material is possible.

embodiments

The following stabilizers are used in the examples: Stabilizer 1

1 g of tetra-p-tert-butylcalix (4) arene is suspended in 30 ml of chlorobenzene in a nitrogen atmosphere. 5 g of tert-butyl hydroperoxide are added and the reaction mixture is heated gently for 24 hours under reflux. Subsequently, the solvent and excess tert-butyl hydroperoxide is distilled off in vacuo. The yellow residue is mixed with 20 ml of methanol and heated briefly to boiling. Subsequently, unreacted calix (n) arene is separated by filtration. The resulting yellow solution is concentrated ₍ leaving a solid, glassy yellow residue.

Yield: 790mg Softening point: 23O ⁰ C

Elemental analysis: C 74.31 H 8.09

75.00 8.22

IR Vco = 1 630 cm " ¹ , 1655 cm" ¹ , 1 685 m "\ 1730 cm" ¹

Stabilizer 2

Procedure as for stabilizer 1 with 1 g of hexa-p-tert-butylcalix (6) arene. Yield: 770 mg softening point: 210 ^° C.

Elemental analysis: C 74.16 H 8.40

74.48, 8.19

IR% £ o = 1 629 cm " ¹ , 1652 cm" ¹ , 1685 cm " ¹ , 1730 cm" ¹

8 _OH = 3440cm " ¹ stabilizer3

Procedure as for stabilizer 1 with 1 g of octa-p-tert-butylcalix (8) arene. Yield: 830 mg softening point: 24O ⁰ C

Elemental analysis: C, 75.01, H, 8.22

74.78, 8.15

IR K ^ ₀ = 1621 cm " ¹ , 1645cm" ¹ , 1670cm " ¹ , 1740cm" ¹

δοΗ = 3450 cm " ¹

Example 1 to 8

The light stabilizers were mixed on a laboratory roll mill at 105 to 140 ⁰ C or a laboratory extruder at 180 to 200 ⁰ C cylinder temperature and pressed on a press from the granules films of 0.05 mm thickness. The pieces of film were weathered with filtered xenon arc light (Xenontest 150), optionally with sprinkling (every 30 min., 0.5 min. Sprinkling of Xenontest 450). The aging process was monitored by IR spectrometer by measuring the extinction of the co-valence vibration at 1 720 cm ^-1 The sample is considered damaged once the extinction of E = 0.1 is reached.

Example Additions Bereg- Concentr. Time

Weight (%) (H)

bisE = 0.1

example 1 none No 0.0 450 (Comparison) Yes 0.0 740 -polyethylene low density Example 2 oxidation product No 0.3 1150 of tetra-p-tert-butyl No 0.6 1300 calix (4) arene -polyethylene Yes 0.3 1600 low density Yes 0.6 1800 Example 3 oxidation No 0.3 950 hexa-p-tert-butyl No 0.6 1 150 arene calix (6) -polyethylene Yes 0.3 1500 low density Yes 0.6 1750 Example 4 oxidation product No 0.3 600 octa-p-tert-butyl No 0.6 750 arene calix (8) -polyethylene Yes 0.3 900 low density Yes 0.6  1 100

additions Bereg Conc. Time -A- 254 739 example voltage Dimensions (%) (H) to E = 0.1 none No 0.0 475 Example 5 Yes 0.0 700 (Comparison) -LLDPE oxidation No 0.3 850 Example 6 desHexa-p-tert No 0.6 1050 Butylcalix (6) arene Yes 0.3 1200 -LLDPE Yes 0.6 1450 none No 0.0 575 Example 7 Yes 0.0 800 (Comparison) -polyethylene high density oxidation product No 0.3 900 Examples desHexa-p-tert No 0.6 1250 Butylcalix (6) arene • i ^a 0.3 1300 -polyethylene Yes 0.6 1500 high density

Claims (4)

claims: 1. Stabilizers for low molecular weight and high polymer organic materials - especially polyolefins and olefin copolymers, ABS, polyamides and polyesters - against degradation by photooxidation, characterized in that compounds obtained by reacting substituted calix (n) arenes of the general formula in which η = 3 to 8 and R = hydrogen, alkyl, cycloalkyl, aralkyl or aryl radical, with hydroperoxides R'OOH, in which R '= hydrogen, alkyl or aralkyl radical, or with organic or with inorganic peracids be used as light stabilizers, optionally in combination with additives of known light stabilizers other classes and antioxidants. 2. Stabilizers according to claim 1, characterized in that light stabilizers are used which have been prepared by reacting calix (n) arenes with hydrogen peroxide, tert-butyl hydroperoxide, cumyl hydroperoxide or tetralin hydroperoxide. 3. Stabilizers according to claim 1, characterized in that the light stabilizers in combination with other known stabilizers, such as quenchers, UV absorbers, complexing agents, lubricants, antistatic agents are used. 4. Stabilizers according to claim 1, characterized in that the light stabilizers in a concentration of 0.01 to 1.0 Ma .-%, preferably from 0.1 to 0.5 Ma .-%, based on the amount of substrate, and the known Additives in a concentration of 0.01 to 0.6Ma .-%, in particular 0.05 to 0.3 Ma .-%, based on the amount of substrate used.