CS258701B1 - Stabilization composition for polypropylene - Google Patents

Abstract

The solution relates to a stabilizing composition for piperidinol-based polypropylene with antioxidants, which contains 0.01 to 0.3% wt. isocyanurate antioxidant general of formula I wherein R is 3,5- -di-tert-butyl-4-hydroxybenzyl 2,6-dimethyl- -3-hydroxy-4-tert-butylbenzyl or 6-13 ‘, 5‘- di-tert-butyl-4'-hydroxyphenyl / 4-oxa-3- -oxo-hexyl and 0.05 to 1.0 wt. one or multiple 4-substituted- -2,2,6,6-tetramethylpiperidine general of formula II wherein X is hydrogen or methyl and A is acyl, v wherein X is hydrogen or methyl and A is a saturated acyl residue or unsaturated aliphatic carboxylic acid acid with 2 to 18 g carbon atoms in 100 wt. stabilized mixture ·

Description

The invention relates to stabilizing co-compositions for polypropylene based on piperidinol esters with antioxidants.

Polypropylene is very sensitive to heat and light. It must therefore be protected during processing and during use so as to maintain good mechanical, physical and chemical properties for as long as possible. Procedures and methods for its protection are well known. Compositions of primary and secondary antioxidants with UV absorbers of the benzophenone type (US Pat. 4,288,631, Brit. Pat. 1,380,449) and benzotriazoles (US Pat. 4,278,589; 4,278,500) have been used for decades.

More recently, several spherically shielded amine compounds have been patented as light stabilizers for polymers. (Eur. Pat. Appl. 13,682; Europ. Pat. Appl. 17,617; Eur. Pat. Appl. 19,578; Eur. Pat. Z2,997, US Pat. 4,233,412).

2,2,6,6-tetramethylpiperidinol derivatives are among the most potent (US Pat. 3,640,928; 4,265,805: DE-OS 2,560,314; USSR Pat. 817,034; Eur. Pat. Appl. 27 620).

The aforementioned patents disclose that these compounds may be used alone or in combination with other stabilizers, fillers and pigments.

Subject of Japanese patent Japan. Kokai Tokkyo Koho 81 62 834 is light stabilization of polyolefins, wherein a light-stabilized piperidine-based polymeric spherically-shielded amine combined with an isocyanurate antioxidant is used as the light stabilizer. The isocyanurate antioxidant itself is also the subject of Japanese patent 8,066,568.

The secondary and tertiary amines of piperidine in combination with isocyanurate antioxidants are also the subject of Belgian patent 886,428.

Interesting piperidine derivatives as stabilizers for synthetic polymers are discussed in Eur. pat. Appl. 31 304.

Synthetic polymer compositions containing triazine derivatives used as light stabilizers are subject to Eur. Pat. Appl. 22 080.

Well-proven light stabilizers are UV absorbers, the efficiency of which can be further enhanced by combining with antioxidants, the more the higher the concentration we use.

Esters of 2,2,6,6-tetramethyl-4-piperidinol are excellent light stabilizers but do not adequately protect polypropylene during processing or long term thermal stress. For this purpose, it is necessary to combine them with antioxidants in order to have good polymer protection during processing, improved resistance to long-term exposure to elevated temperatures, excellent mechanical properties (strength and ductility) and also to have a higher resistance to UV-exposure.

It has now been found that the above drawbacks are largely overcome by the stabilizer composition for the piperidinol ester-based polypropylene antioxidant compositions of the invention.

The stabilizing composition comprises 0.01 to 0.3 pens. % by weight of an isocyanurate antioxidant of the formula I

R - / yli-R ⁰ (I) wherein

R is 3,5-di-tert-butyl-4-hydroxybenzyl

2,6-dimethyl-3-hydroxy-4-tert-butylbenzyl

or 6- (3 ', 5'-di-tert-butyl-4'-hydroxyphenyl) -4-oxa-3-oxo-hexyl H ^c. f; ... i .... c - n V i>r> · - · '»/ \ rw'

H ^ CH ^ ^j Voh \ JCH-, cr cm.

and 0.05 to 1.0 wt. one or more 4-substituted-2,2,6,6-ietramethyl-4-piperidine derivatives of formula II

in which

X is hydrogen or methyl and A is an acyl radical derived from a saturated or unsaturated carboxylic aliphatic] acid having a double bond of 2 to 18 carbon atoms at 100% by weight. stabilized mixture.

It has also been found to be advantageous if the mixture is a compound of formula (I) wherein R is 3,5-di-tert-butyl-4-hydroxybenzyl and a mixture of derivatives of formula (II) containing 37 to 70% by weight. % of a derivative in which A is stearoyl, 29 to 52 wt. % of a derivative in which A is palmitoyl, 0.2 to 6 wt. % of a derivative in which A is heptadecanoyl, 0.1 to 5 wt. a derivative in which A is myristoyl and 0.2 to 6% by weight in which A is oleoyl.

The present compositions have good processing stability, are characterized by improved resistance to thermo-oxidative degradation, provide excellent mechanical properties of polypropylene, and have excellent light stability. Farehne are still. They can be used to prepare any product, in particular polypropylene fibers. We recommend combining them with other additives such as antioxidants, Ca stearate, UV absorbers, fillers, pigments and the like.

The compositions may be prepared by conventional methods used in the production of stabilized polypropylene.

The concentration of isocyanurate derivatives is used in the range of 0.01 to 0.3% by weight, most often 0.030 to 0.15% by weight. Sheets.

The concentration of piperidine derivatives is in the range of 0.05-1.0% by weight, preferably 0.1-0.5% by weight. Sheets.

The use of the present composition provides technical advantages such as improved mechanical properties, improved processing resistance, increased thermal and light stability of the polypropylene. By using optimal concentrations of the individual components of the mixture, an economic effect can also be achieved.

The following examples illustrate the invention.

The preparation of the blend as well as the type of polypropylene are given before the individual examples. Foils of 0.5 mm thickness were prepared by pressing at 260 ° C, at a pressure of 19.6 MPa for 10 minutes.

Rated:

- processing stability on a Brabender plastograph (NSR) by exposing polypropylene at 190 ° C in air until the relative viscosity drops to half (min.), Thermal stability in a STE-39 (Chirana) dryer at 140 degrees Celsius by monitoring the time to · onset of degradation of five parallel samples (hr.J, - light stability in Xenoteste 450 (Original Ilanau, NSR)) by monitoring the irradiation time in hrs until the carbonyl increments of 0.3 under conditions: black panel temperature 45 ° C, rh252501 bone 60 %, shower 9 min, dry run 51 min, frame rotation When evaluating the fiber temperature of 35 ° C in Xenotte 150 (Original Hanau) until the fiber strength decreases to half (50 pere) in natural weathering in I-Iurban (Southern Slovakia - - an average of 1,900 hours of sunshine per year) and in Poprad (Northern Slovakia - percentage decrease in fiber strength after some time).

Example 1

The ingredients were mixed into unstabilized powdered polypropylene (PP) type HPP with IT ₂₃ o = 8.5 g / 10 min, isotactic, and 96.5% on a Brabender plastograph at temperature.

1,800 h sunny light) 190 ° C 10 min., N ₂ . Stabilization system processing Thermal stab. light Stab. 450 slab. (min.) 2 dry. 140 [deg.] C Xenotest pQv. stressed (H) (H) (H) unstabilized PP 7 8 300 150 0.15% HALS — 1 16 50 2 800 3 400 0.15% AO-1 + 0.15 61 800 3 800 4 200

HALS 1

HALS = Hindered Amine Light Stabilisers is used to designate sterically shielded ainines.

HALS-1: mixed stabilizer containing

03.4 wt. 4-stearoyloxy-2,2,6,6-tetramethylpiperidine,

29.1 wt. 4-palmitoyloxy-2,2,6,6-tetramethylpiperidine,

4.3 wt. 4-heptadecanoyloxy-2,2,6,6-tetramethylpiperidine,

1.9 wt. 4-myristoyloxy-2,2,6,6-tetramethylpiperidine

1.3 wt. 4-oleoyloxy-2,2,6,6-tetramethylpiperidine AO-1:

1,3,5-tris- (3,5-di-tert-butyl-4-hydroxybenzyl) -isocyanurate Example 2

Unstabilized powder PP HPF type with IT ₂₃₀ = 9 g / 10 min. 96.9% of the isotacticity are on a Brabender plastograph at 190 ° C, N ₂ , 10 min. mixed as follows:

B.

Stabilization system Thermal stability Light stability ° / o weight (h) Xenotest 450 (h)

0.1 % AO-1 800 1500 0.1 % AO-2 + 0.2 % HALS 1 1100 5 800 0.1 % AO-3 + 0.2 % HALS 1 1 500 7 000 0.1 % AO-1 + 0.2 % HALS 2 860 5 000 0.1 % AO-1 + 0.3 % HALS 1 980 5 700 0.1 % AO-1 + 0.3 % HALS-4 1700 5 700 0.1 % AO-1 + 0.3 % HALS 3 940 5 700 0.1 % AO-1 + 0.3 % UVA-1 1 000 2 600

HALS-2: 4-etanoyloxy-2,2,6,6-tetramethylpiperidine

HALS-3: 4-octanoyloxy-1,2,2,6,6-pentamethylpiperidine

HALS-4: Poly / 2-N, N'-di- (2,2,6,6-tetramethyl-4-piperidinyl) hexanediamine-4- (1-amino-1,1,3,3-tetaramethylbutane) ) -l, 3,5-triazine

UVA-1: 2-hydroxy-4-octyloxybenzophenone

AO-2: 1,3,5-tris- (2,6-dimethyl-3-hydroxy-4-tert-butylbenzyl) -isocyanurate

AO — 3: 1,3,5-tris- (3‘, 5‘-di-tert-butyl-4‘-hydroxyphenyl) -4-oxa-3-oxo-hexyl-isocyanurate

Example 3

From isotactic polypropylene TATREN HPF powder (IT = 9.5 g / 10 min.), The compositions were prepared by granulating at 230 ° C and used to prepare polypropylene fibers on a spinning extruder with a screw diameter of 32 mm using a spinneret 33 ^of 03 at speed nnvivanla 450 m / min. The spinning temperatures were in the range of 312-315 ° C. The wound fibers were deformed at 135 ° C to a degree of one. 5,0 dtex.

25B701

composition

0.1% AO — 1 + 0.2% HALS — 1

0.1% AO — 1 + 0.3% HALS — 1

0.1% AO — 1 + 0.3% HALS — 4

0.1% AO — 4 + 0.5-5% AO — 5 + + 0.3% UVA — 1

AO-4: 2,6-di-tert-butyl-4-methylphenol AO-5: distearyl thiodipropionate

attaches

Of coiled fibers prepared as in

Decrease of strength after 1 890 h fire. in Xenotest (%) the half-life of 990 h of Example 3, fiber-shaped fibers were prepared by deformation to a degree of deformation of - 4.0 with a KK-2 shaping to a 3-7 cm bend. The stranded fibers were fixed in a dry air stream at 130 ° C.

Stabilization system% by weight

Natural weather. Start.

Poprad (loose) Poprad (sheet) drop ° / o ρδν. strength after 1,780 h smooth arc.

drop% p3v. after 1 780 h smooth obl.

Xenotest 150 Drop% pov. strength after 990 h half-life smooth obl.

0.1% AO — 1 + 0.2% HALS — 1 30 29 24 37 24 700 0.1% O-1 + 0.2% HALS-4 25 28 25 29 30 640 0.1% AO-4 + 0.55% AO-5 + + 0.3% UCA-1 Half 1400 750 980 670 930 840 strength Example 1 and d 5 for conditions listed in example no

and 4.

The staple dyed in the mass was prepared

Stabilization system Light stability half-life Xenotest 450% by weight strength 1% Gron. Gelb. GR (τ / 2 —h)% Sandorin Rot BR

0.1 AO — 1 + 0.3 HALS — 1 450 460 0.1 AO — 1 + 0.3 HALS — 4 670 630 0.1 AO — 4 + 0.55 AO — 5 + +0.3 UVA — 1 310 280

Example 6

From powdered isotactic polypropylene having an IT value of 10.3 g / 10 min, powder compositions were prepared which were granulated at 230 ° C. Pigments for coloring in the form of a concentrate were added to the granules so that the pigment concentration was 1%. The color compositions were spun on a spinner with a diameter of 32 mm at 305 ° C through a spinneret 33/03 at a winding speed of 450 m / min. Smooth fibers with a single fineness of 5.0 dtex were prepared from the wound fiber by deforming at 130 ° C.

composition

Strength decrease (%) after 1000 h 1 ° / o Sandorin rot Bl in Xenoteste 450% Gromophtal gelb GR

0.1% AO — 1 + 0.3% HALS — 1 0.1% AO — 1 + 0.3% HALS — 4 0.1% AO — 4 + 0.55 ° / o AO — 5 + +0.3% UVA — 1 Half Fortress

32

8 half-life

530 h 410 h

All of the mixtures in Examples 1 to 6 contained 0.15% Ca stearate.

Claims (2)

SUBJECT We claim: A stabilizer composition for polypropylene based on piperidinol esters with antioxidants, characterized in that it contains 0.01 to 0.3 wt. isocyanurate antioxidant of formula I R O. bl r.O R In which R is 3,5-di-tert-butyl-4-hydroxybenzyl, 2,6-dimethyl-3-hydroxy-4-tert-butylbenzyl or 6- (3 ', 5'-di-tert-butyl-4'- hydroxyphenyl] -4-oxa-3-oxo-hexyl and 0.05 to 1.0% by weight of one or more 4-substituted-2,2,6,6-tetramethylpiperidine derivatives of formula (II): X is hydrogen or methyl; and A is an acyl radical derived from a saturated or unsaturated aliphatic carboxylic acid having from 2 to 18 carbon atoms in 100 wt. stabilized mixtures. 2. A stabilizing composition according to claim 1, wherein the isocyanurate antioxidant of formula I comprises: 1,3,5-tris- (3 ', 5'-di-tert-butyl-4'-hydroxybenzyl) isocyanurate and as a 4-substituted-2,2,6,6-tetramethylpiperidine of the formula II contains a mixture of derivatives consisting of from 37 to 70% by weight of a derivative in which A is stearoyl, from 29 to 52% by weight of a derivative in which A is palmitoyl, from 0.2 to 6% by weight of a derivative in which A is heptadecanoyl, from 0, 1 to 5% by weight of a derivative in which A is myristoyl and from 0.2 to 5% by weight of a derivative in which A is oleoyl and X is as defined in point 1.