CS232321B1 - A method of stabilizing polyolefins with simultaneous antistatic treatment - Google Patents

Abstract

A reduction in the electrolysis of polyolefins and an increase in their stability against oxidation with a single additive is achieved by using an antistatic-nonionic surfactant of the type bis-oxyethylated higher aliphatic amine with tertiary nitrogen of the general formula (0Η2-0Η2-Ο)·χΗ R-N<f (CH2-CH2-O4yH R=C10 to C n=x+y=2 to 20 10 Substance of this type significant improves the dispersion of polar additives in the polymer.The condition is that it is protected from photolysis by ultraviolet radiation with a suitable photostabilizer.

Description

B (54) Method of stabilizing polyolefins with antistatic treatment

The reduction of the electrolysis of polyolefins and their stability to oxidation by a single additive is achieved by using an antistatic-nonionic surfactant of the bis-oxyethylated higher aliphatic amine type with a tertiary nitrogen of the general formula (0Η ₂ -0Η ₂ -Ο) · _{χ χ}

RNf (CH ₂ -CH ₂ -O 4 _y H)

R = C ₁₀ to C n = x + y = 2 to

A substance of this type significantly improves the dispersion of polar additives in the polymer. The condition is that it is protected from photolysis by ultraviolet radiation with a suitable photostabizer.

The invention relates to a method of stabilizing polyolefins with an antistatic additive. A suitable surfactant introduced into the polymer exhibits, in addition to the known antistatic effect (depressions, electrisations), a considerable antioxidant effect (heating the polymer to oxidation).

The hitherto used method of stabilizing polyolefins against exidation was accomplished by the addition of a suitable stabilizer. In order to inhibit photooxidation, light stabilizers are used which, according to the mechanism of action, are divided into several groups (carbon black, ultraviolet absorbers, arousal quenchers, spatially shielded piperidine derivatives and others). / RANBY, B.-RABEK, J. F .: Photodegradation, Photooxidation and Photostabilization of Polymer, Wiley-Interscience Publication, London 1975; DOLEŽEL, B .: Resistance of Plastic and Rubber, SNTL,

Praha 1981; GUGUMUS, F .: Rev. gen. Caoutchoucs Plast., 53, 1976, no. 558, p. 67-71 /.

Antioxidants of the type of spatially shielded phenols, spatially shielded aromatic amines, thiodiproplonic acid esters, organic phosphites, thiobisphenols and the like are applied to the polymers to protect against tennooxidels. Polymer Stabilization, Ed. by Hawkins W.L., Wiley-Interscience, New York 1972; Degradation and Stabilization of Polymere. Ed. by Gueskens, G., Applied Science Publishers Ltd, London 1975 /. Some combinations of stabilizers appear synergism, which is used for their purposeful selection. Technical practice also uses multifunctional stabilizers, acting as photo-1 thermostabilizers (prospectus of C1BA-GEIGY: Irgastab 2002). The literature also continuously informs about new types of substances with a stabilizing effect which have been tested in laboratory models and have not yet been tested in practice / SCHULZ, M.-SCHLIMPER, R.-WEGWART, H.: Plaste u. Kautschuk, 24, 1977, no. 6, p. 401-404;

RABEK, J.F.-RANBY, B.-ARCT, J. et al., Eur. Polym. J., Jfi, 1982, no. 1, p. 8, -87 /.

The reduction in the electrolysis of polyolefins can be achieved by chemical or physical modification. The chemical route involves inoculating polar substituents on the backbone, requiring more expensive technology. Physical modification is realized by application of so-called. antistatic agent (antistatic) on the surface of the product (surface antistatic treatment) or in the polymer mass (internal antistatic treatment). / VASILENOK, J .: Zashchita Polimerov ot staticheskogo elektrichestva, 1 ed., Khimija-Leningrad 1975 /.

For polyolefins, nonionic surfactants with the nitrogen heteroatom of the oxyethylated aliphatic amine type and the oxyethylated aliphatic amide type have proved to be the most effective antistatic agents:

(CH ₂ -CH ₂ -O 4 - _x H

R-N (CH ₂ CH ₂ O) - _y H, where n = x + y = 2; R = the higher alkyl (e.g. C to Cjq _Q1) m _{(CH2 CH2} O). _x h

R-C-N4.

(CH ₂ CH ₂ O) - _y H, wherein n * i + y = 2; R = higher alkyl, (eg G ₁₀ to 0 ₂ θ)

If the application of the polyolefin requires both stabilization and antistatic treatment, both stabilizers and antistatic agents are introduced into the polymer. The diverse nature of the ingredients determines the formation of polymer-stabilizer-antistatic interactions, which often in addition to the faster degradation of the polymer matrix. (ŠEVERDYAJEV, ON-SOIL, VS-ALLENOVA, TA and 1 .: Plast. Maaay, 20, 1978, No. 6, pp. 74-75). This situation then requires increased dosing of the stabilizers, which means a rise in production costs the resulting effect is not always adequate.

These drawbacks are eliminated by the subject-matter of the invention, which is characterized in that, as the antioxidant, and at the same time as an internal antistatic agent used surfactant-type bis-oxyethylated tertiary nitrogen amine with the formula _{(CH2 -CH2} -O) - _x HR-C _{1 q} and C ₂₀

RN ^ ^Xx (CH ₂ -CH ₂ -O> _y H n = x + y = 2 to 10, in the case of UV radiation in combination with effective light stabilizers such as shielded amines, Ni-complex carriers, combination of UV absorbers benzophenol or benzotriazole type 30 quenchers based on Ni-complexes.

The advantages of the process according to the invention are to achieve two effects - reducing electrification and increasing the oxidation stability of the polyolefin - with only one additive. These properties of the subject antistatic, as well as the ability to disperse additives perfectly, mean a reduction in manufacturing costs.

EXAMPLE

Foils of low density polyethylene (LDPE) with a thickness of 0.16 mm containing 0.2% antistatic _{type-CH2-CH2-OH}

CH ₃ - (CH ₂ ) ₇ n /

The CH ₂ -CH ₂ -OH was subjected to thermooxidation in a hot air stream at 85 ° C. At the same time, the film without additive was exposed and degraded after 2,000 hours. Since the mechanical properties of the antistatic additive film were still at the initial level after 3,600 hours, the temperature rose to 100 ° C. Under these conditions, the film lasted for 400 hours.

Example 2

0,18 mm thick rPE foil containing 0,2% amine surfactant (ch ₂ -ch ₂ ) _x h R = C, ₀ to c, _and

R N ^ \ (CH _{2 -CH} -01 H n + x .y = 7 was subjected to thermal oxidation at 100 ° C. The thermal loading lasted 5000 hours, whereas the comparative foil not containing degraded after 800 hours.

Example 3

For comparison, they were exposed to a weathering aging of 0.10 mm thick rPE foil with additive eystems:

(a) 0,2% Tinuvin 326, t. 2- (2'-hydroxy-3'-tert-butyl-5'-methylphenyl) -5-chlorobenzotriezole, 0.1% Irgastab 2002, m.p. nickel-bis-o ~ ethyl (3,5-di-tert-butyl-4-hydroxybenzyl) phosphonate,

0.2% Irganox 1076, m.p. octadecyl-1- (3,5-di-tere.butyl-4-hydroxyphenyl) propionate,

(b) 0,2% Tinuvin 326 '

0.1% Irgastab 2002

0.2% of the amine surfactant of Example 1

The aging behavior of both types of film is evident from the development of carbonyl absorbance, monitored by infrared spectroscopy (Table 1) and the decrease in strength (Table 2) as a function of exposure time in months.

Table 1

Development of carbonyl absorbance of PE-foil during weathering

Aditív- ny sy ~ hundredth Absorbance of carbonyl 0 1.5 5 6 8 10 12 13.5 15 17 mes. month * month * mes · mes. mas. mes · mes. mes. mes · and 0.01 0.03 0.12 0.16 0.16 0.21 0.23 0.36 0.44 0.80 b 0.01 0.02 0.08 0.09 0.09 0.11 0.13 0.18 0.32 0.58

TabuTka 2

Change of PE foil strength during weathering

Aditív- ny sy- hundredth Breaking strength (MPa) 0 1.5 5 6 8 10 12 13.5 15 17 mes · mes. month * mes. mes · mes · mes · mes · mes · mes · and 16.0 14.7 14.5 14.0 13.8 12.0 10.1 9.3 8.5 7.9 b 16.0 14.7 13.5 13.3 12.7 12.5 13.5 12.6 11.0 8.6

System a, considered proven in engineering practice, has inferior properties to 1A 11b, which, in the current antistatic treatment (surface resistance dropped from 10 ft ^{to 10} Λ>, does not require the presence of antioxidants. Ensuring two effects - stabilizing 1 electrolysis reduction) at lower production costs.

Example 4

The enhancement of stabilizer dispersion due to surfactant can be compared to the solubility of Irgastab 2002 stabilizer in paraffin oil. The effect of the presence of surfactants on the solubility of the stabilizer is shown in Table 3.

Table 3

Dependence of solubility of Irgastab 2002 in paraffin oil on the content of bis-oxyacylated aliphatic amine (R ^ C,,, x + y «2)

Tenzld content (wt%) 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 Solubility of Irgastab (wt.) 0 0.50 0.85 1.30 1.68 2.0 2.17 2.30 2.35 2.40

23232!

The object of the present invention can be used in the plastics, fiber and electrical industries to modify the properties of polyolefins intended for applications requiring stabilization while reducing electrification of the material.

Claims (1)

The subject matter of the present invention can be used in the plastics, fiber and electro-technical industries to modify the properties of polyolefins intended for application requiring stabilization and at the same time reduced electrification of the material. SUMMARY OF THE INVENTION The present invention relates to a method for stabilizing polyclothins with the present anti-static treatment by using a bis-oxyethylated amine surfactant of the general formula (CH 2 -CH 2 -O> -xHR 10 C 10 to 10 -H 2 O) as an antioxidant and at the same time as an internal antistatic agent. C20N6 (CH2-CH2-O3yHn = x + y = 2-10, in the case of UV irradiation in combination with effective light stabilizers such as shadowed amines, Ni-complex-based quenchers, combination of benzophenone butobenzotriazole UV absorbers) type with Ni-complex-based quenchers