IE913141A1 - Polyolefin molding composition for producing calendered¹films - Google Patents

Abstract

The polyolefin moulding material described consists of: 95-99.98 % by wt. of an olefin polymer, 0.01-2.5 % by wt. of at least one compound of formula (I), formula (II), formula (III), formula (IV): R<4> - (S)x - R<4> or formula (V), plus at least one phenolic anti-oxidant. This material, which is suitable for the production of calendered sheet, has only a very slight tendency to stick to the hot calendering rolls and the polymer molecules have only a slight tendency to decompose during processing.

Description

Description Polyolefin molding composition for producing calendered films The invention relates to a polyolefin molding composition 5 for producing calendered films that sticks to the hot metal surfaces of the processing machines only to a minimal extent and does not drip off the hot rolls during processing.

It has been known for a long time that calendering can be used to process in particular PVC mixtures, plasticized or unplasticized, into technically high-grade film webs. A particular difficulty with this technology is the tendency of the hot polymer melt to stick to the metal surfaces of the calender rolls. Numerous recipes have been developed to control this stickiness with suitable lubricating and release agents.

The tendency of the polymer melt to stick to the hot metal surfaces of processing machines can also be reduced by utilizing the lubricating effect of surface-active substances, as are used for example as antistatic agents in PVC mixtures .

For a plasticated polymer material to be processible into film webs by calendering it must generally possess a wide softening range and a sufficiently high viscosity at the appropriate processing temperature and shear gradient.

PVC mixtures do possess these necessary high melt viscosities. However, high polymers such as polypropylene and polyethylene have only low melt viscosities. Whereas the melt viscosity of a PVC molding composition remains relatively unchanged to the point of the material sticking to the rolls and beyond that until the end stability is reached, the viscosity of a polypropylene molding composition decreases very markedly until the tack-free time is reached and especially thereafter, and - 2 thus greatly hinders the processing on calendering ranges.

For technological and economic reasons (e.g. a wish to use a material of lower density or made of an apolar plastic) there has been a long-felt need to produce such calendered films not only on the basis of PVC but also on the basis of polyolefins, e.g. homopolymers and copolymers of ethylene or of propylene. Hitherto this was difficult because, on calendering, commercial polyolefin compositions quickly stick to the metal rolls and become very liquid, resulting in films which have completely inadequate physical properties or even in dripping from the calender rolls.

Nor did the technique known from the calendering of PVC of adding lubricants which are adapted in polarity to the plastic lead to the desired result for polyolefins.

It has now been found that the disadvantages described can be circumvented by using for the production of films by the calendering of polyolefins molding compositions to which specific chemicals already known as stabilizers are added.

The present invention thus provides a polyolefin molding composition for producing calendered films, consisting of from 95 to 99.98% by weight of an olefin polymer, from 0.01 to 2.5% by weight of at least one compound of the formula I (I), of the formula II 0—CH / \ Ο—CH /C\ ch2-ox *Ρ - OR CH^O^IUJr of the formula IV r4 - <s>x - r4 (IV) or of the formula V (R3 - S - 2)2 - Cf- 0 - CH2)4 f C 0 (V), where R1 and R2 are identical or different and each is hydrogen, methyl, t-butyl, 1,1-dimethylpropyl, cyclohexyl or substituted or unsubstituted phenyl, R3 is Ce- to C22-alkyl or a radical of the formula where R1 and R2 are each as defined above, R* is Ce- to C20-alkyl or a group of the formula R5-O-C-(CH2) 2-, where R5 is C8- to C20-alkyl, II o A is biphenylene, and x is an integer from 1 to 5, and from 0.01 to 2.5% by weight of at least one phenolic antioxidant.

The molding composition of the invention is constituted to an extent of from 95 to 99.98, preferably from 98 to 99.95, % by weight by an olefin polymer. Suitable olefin polymers are polymers of mono- or diolefins, for example polyethylene, which may be crosslinked, polypropylene, polyisobutylene, polybutene-l, polymethylpentene-1, - 4 polyisoprene or polybutadiene, and also polymers of cycloolefins, for example of cyclopentene or norbornene, mixtures of the aforementioned polymers, for example mixtures of polypropylene with polyisobutylene, copolymers of mono- and diolefins with one another or with other vinyl monomers, for example ethylene-propylene copolymers, propylene-butene-1 copolymers, propyleneisobutylene copolymers, ethylene-butene-1 copolymers, propylene-butadiene copolymers, isobutylene-isoprene copolymers, ethylene-alkyl acrylate copolymers, ethylenealkyl methacrylate copolymers, ethylene-vinyl acetate copolymers or ethylene-acrylic acid copolymers and salts thereof (ionomers), and also terpolymers of ethylene with propylene and a diene such as hexadiene, dicyclopentadiene or ethylidenenorbornene.

Of the polymers mentioned, the preferred ones are homoand copolymers of propylene and also mixtures thereof with terpolymers of propylene, ethylene and a diene.

The molding composition of the invention is further 20 constituted to an extent of from 0.01 to 2.5, preferably from 0.025 to 1, % by weight by at least one compound of the group consisting of phosphorus compounds of the formula I, phosphorus compounds of the formula II, phosphorus compounds of the formula III, sulfur compounds of the formula IV and sulfur compounds of the formula V.

In the formula I R1 and R2 are identical or different and each is hydrogen, methyl, t-butyl, 1,1-dimethylpropyl, cyclohexyl or substituted or unsubstituted phenyl. In the formula II R1 and R2 are each as defined above and A is biphenylene. In the formula III o-ch2 -0 - < ...A ch2-°x.

(III) o-ch2 'ch2-o R3 is C8- to C22-alkyl/ preferably C12- to C18-alkyl, or a D 1 radical of the formula where R1 and R2 are each as defined above. In the formula IV R4 - (S)x - R* (IV) R* is Cg— to C20-alkyl, preferably C12- to C18-alkyl, or a group of the formula R5-O-C-(CH2)2-, where R5 is C8- to C20-alkyl, preferably C12- to C18-alkyl, 15 and x is an integer from 1 to 5. In the formula V (R3 - S - (CH2)2 - C - 0 - CH2)4 e C (V) R3 is as defined above.

Examples of compounds of the formula I are r r1 \_ - R1 - R1 Z : P- i3 ; P- 3 ' Z J - R2 • Of these compounds, the preferred one is Examples of compounds of the formula II are R2 R2 R1-0 -R1 Of these compounds, the preferred ones have R1 = R2 = t-butyl and A =4,4'-biphenylene.

Examples of compounds of the formula III are /0-ch2X /CH2-0\ c12-o-p c p-o-c12 \o-ch2/ \ch2-o/ /O-ch2X /CH2-O\ c18-o-p c p-o-c18 \o-ch2/ \ch2-o/ /0-ch2X /CH2-O\ Ο-P C P-0 \o-ch2/ \ch2-o/ Of these compounds the preferred ones are - 7 /O-CH2X /CH^Oy C18-o-p c P-o-c18 \o-ch2/ \ch2-o/ /O-ch2\ /CH2-O\ 0-P c \o-ch2/ \ch2-o/ Examples of compounds of the formula IV are S-t-CH2-CH2-C-O-C12H2s)2 tl ch3-(ch2)17-c-o-ch2-ch2-s-ch2-ch2-0-C-(CH2)17-ch3 i, ii 0 CH3-(CH2)17-S-S-(CH2)17-CH3 CH3-(CH2)11-S-S-(CH2)x1-ch3 Of these compounds, the preferred ones are S-t-CH2-CH2-C-0-C12H25)2 II ch3- (CH2) 17- c- o- ch2-ch2- s-ch2-ch2- 0-C- (ch2 ) 17-ch3 II »1 0 CH3-(CH2)17-S-S-(CH2)17-CH3 Examples of compounds of formula V are (C8-S-(CH2)2-C-0-CH2)4«C n 0 - 8 (C12-s-(CH2)2wC-0-CH2)48C I» (C18-s-(CH2)2-C-O-CH2)4SC n 0 Of these compounds, the preferred one is (Ci2-S-(CH2)2-C-O-CH2)4gC n 0 As well as the compounds of the formula I, II, III, IV or V, which can be used alone or mixed, the molding composition of the invention contains from 0.01 to 2.5, preferably from 0.025 to 1, % by weight of at least one phenolic antioxidant. Suitable antioxidants of this type are Alkylated monophenols, for example 1,6-di-t-butyl4-methylphenol, 2-t-butyl-4,6-dimethylphenol, 2,6-di-t10 butyl-4-ethylphenol, 2,6-di-t-butyl-4-n-butylphenol, 2.6- di-t-butyl-4-i-butylphenol, 2,6-dicyclopentyl4-methylphenol, 2-(a-methylcyclohexyl) 4.6- dimethylphenol, 2,6-dioctadecyl-4-methylphenol, 2.4.6- tricyclohexylphenol, 2,6-di-t-butyl15 4-methoxymethylphenol.

Alkylated hydroquinones, for example 2,6-di-t-butyl4-methoxyphenol, 2,5-di-t-butylhydroquinone, 2,5-di-tamyl-hydroquinone, 2,6-diphenyl-4-octadecyloxyphenol.

Hydroxylated thiodiphenyl ethers, for example 20 2,2 '-thiobis(6-t-butyl-4-methylphenol) , 2,2'-thiobis(4-octylphenol), 4,4'-thiobis(6-t-butyl3-methylphenol), 4,4'-thiobis(6-t-butyl-2-methylphenol). - 9 Alkylidene bisphenols, for example 2,2' -methylenebis (6-tbutyl-4-methylphenol), 2,2'-methylenebis(6-t-butyl4-ethylphenol), 2,2'-methylenebis[4-methyl-6-(amethylcyclohexyl)-phenol], 2,2'-methylenebis(4-methyl5 6-eyelohexylphenol), 2,2'-methylenebis(6-nonyl4- methylphenol), 2,2'-methylenebis(4,6-di-t-butylphenol), 2,2'-ethylidenebis(4,6-di-t-butylphenol), 2,2' -ethylidenebis(6-t-butyl-4-isobutylphenol), 2,2’-methylenebis[6-(α-methylbenzyl)-4-nonylphenol], 2,2'-methylenebis[6-(a,α-dimethylbenzyl)-4-nonylphenol], , 4 ' - methylenebis (2 , 6-di-t-butylphenol) , 4,4'-methylenebis(6-t-butyl-2-methylphenol), 1,1-bis(5-tbutyl-4-hydroxy-2-methylphenyl)-butane, 2,6-di-(3-tbutyl-5-methyl-2-hydroxybenzyl) -4-methy1pheno1, 1,1,3-tris-(5-t-butyl-4-hydroxy-2-methylphenyl) butane, 1,1-bis-(5-t-butyl-4-hydroxy-2-methylphenyl)-3-ndodecylmercaptobutane, di-(3-t-butyl-4-hydroxy5- methylphenyl)-dicyclopentadiene, di-[2-(3'-t-butyl2 ' -hydroxy-5 ' -methylbenzyl) -6-t-butyl-4-methylphenyl ] terephthalate, glycol bis-3,3-bis(4'-hydroxy-3'-tbutylphenyl) butanoate.

Benzyl compounds, for example l,3,5-tri-(3,5-di-t-butyl4-hydroxybenzyl)-2,4,6-triraethylbenzene, di(3,5-di-tbutyl-4-hydroxybenzyl) sulfide, isooctyl 3,5-di-t-butyl25 4-hydroxybenzylmercaptoacetate, bis (4-t-butyl-3-hydroxy2,6-dimethylbenzyl) dithiol terephthalate, 1.3.5- tris(3,5-di-t-butyl-4-hydroxybenzyl) isocyanurate, 1.3.5- tris(4-t-butyl-3-hydroxy-2,6-dimethylbenzyl) isocyanurate, dioctadecyl 3,5-di-t-butyl-4-hydroxybenzyl phosphonate, calcium salt of monoethyl ester of 3,5-dit-butyl-4-hydroxybenzyl phosphonic acid.

Acylaminophenols, for example 4-hydroxylauranilide, 4-hydroxystearanilide, 2,4-bisoctylmercapto-6-(3,5-di-tbutyl-4-hydroxyanilino)-s-triazine, N-(3,5-di-t-butyl35 4-hydroxyanilino)-s-triazine, octyl N-(3,5-di-t-butyl4-hydroxyphenyl) carbamate. - 10 Esters of β-(3,5-di-t-butyl-4-hydroxyphenyl)propionic acid with monohydric or polyhydric alcohols, for example with methanol octadecanol 1,6-hexanediol neopentyl glycol thiodiethylene glycol diethylene glycol triethylene glycol pentaerythr ito1 trishydroxyethyl isocyanurate dihydroxyoxalamide Esters of β-(5-t-butyl-4-hydroxy-3-methylphenyl)propionic 10 acid with monohydric or polyhydric alcohols, for example with methanol octadecanol 1,6-hexanediol neopentyl glycol thiodiethylene glycol diethylene glycol triethylene glycol pentaerythritol trishydroxyethyl isocyanurate dihydroxyoxalamide Amides of β-(3,5-di-t-butyl-4-hydroxyphenyl)propionic acid, for example N,N'-di-(3,5-di-t-butyl4-hydroxyphenylpropionyl)-hexamethylenediamine, N,N'-di20 ( 3 , 5-di-t-butyl-4-hydroxyphenylpropionyl) trimethylenediamine , N,N'-di-(3,5-di-t-butyl4-hydroxyphenylpropionyl)-hydrazine.

These compounds are used alone or mixed. Preference is given to esters of β-(3,5-di-t-butyl25 4-hydroxyphenyl)propionic acid with octadecanol, pentaerythritol or trishydroxyethyl isocyanurate, 1,1,3-tris (5-t-butyl-4-hydroxy-2-methylphenyl) butane, 1 , 3,5-tris(3,5-di-t-butyl-4-hydroxybenzyl) 2,4,6-trimethylbenzene, 1,3,5-tris(3,5-di-t-butyl30 4-hydroxybenzyl) isocyanurate, 1,3,5-tris(4-t-butyl3-hydroxy-2,6-dimethylbenzyl) isocyanurate and glycol bis-3,3-bis (4'-hydroxy-3'-t-butylphenyl)butanoate.

Furthermore, the molding composition of the invention may - 11 contain further additives, for example: UV absorbers and stabilizers, for example 2-(2-Hydroxymethyl)benzotriazole, for example the 5'-methyl , 3' ,5 '-di-t-butyl, 5'-t-butyl5 5'-(1,1,3,3-tetramethylbutyl), 5-chloro-3',5-di-t-butyl, -chloro-3'-t-butyl-5'-methyl, 3'-sec-butyl-5'-t-butyl, 4'-octoxy, 3,5'-di-t-amyl or 3',5'-bis (a ,adimethylbenzyl) derivative. 2-Hydroxybenzophenones, for example 4-methoxy, 4-octoxy, 4-decyloxy, 4-benzyloxy, 4,2',4'-trihydroxy 4,4'-dimethoxy derivatives. the 4-hydroxy, 4-dodecyloxy, or 2'-hydroxyEsters of substituted or unsubstituted benzoic acids, for example 4-t-butylphenyl salicylate, phenyl salicylate, octylphenyl salicylate, dibenzoylresorcinol, bis(4-tbutylbenzoyl)resorcinol, benzoylresorcinol, 2,4-di-tbutylphenyl 3,5-di-t-butyl-4-hydroxybenzoate, hexadecyl 3,5-di-t-butyl-4-hydroxybenzoate.

Acrylates, for example ethyl or isooctyl a-cyano-0,β20 diphenyl acrylate, methyl α-carbomethoxy cinnamate, methyl or butyl a-cyano-0-methyl-p-methoxy cinnamate, methyl α-carbomethoxy-p-methoxy cinnamate, N-(£carbomethoxy-0-cyanovinyl)-2-methylindoline.

Nickel compounds, for example nickel complexes of 2,2'-thiobis[4-(1,1,3,3-tetramethylbutyl)phenol], such as the 1:1 or 1:2 complex, with or without additional ligands such as n-butylamine, triethanolamine or Ncyclohexyldiethanolamine, nickelalkyl dithiocarbamates, nickel salts of monoalkyl, such as methyl or ethyl, esters of 4-hydroxy-3,5-di-t-butylbenzylphosphonic acid, nickel complexes of ketoximes such as 2-hydroxy4-methylphenylundecylketonoxime, nickel complexes of l-phenyl-4-lauroyl-5-hydroxypyrazole, with or without additional ligands. succ inate, sebacate, Sterically hindered amines, for example bis (2,2,6,6-tetramethylpiperidyl) sebacate, bis (2,2,6,6 -tetramethylpiperidyl) bis (1,2,2,6,6-pentamethylpiperidyl) bis (1,2,2,6,6-pentamethylpiperidyl) n-butyl-3,5-di-tbutyl-4-hydroxybenzylmalonate, condensation product of l-hydroxyethyl-2,2,6,6-tetramethyl-4-hydroxypiperidine and succinic acid, condensation product of N,N'(2,2,6,6-tetramethyl-4-piperidyl)hexamethylendiamine and 4-t-octylamino-2,6-dichloro-l,3,5-s-triazine, tris (2,2,6,6-tetramethyl-4-piperidyl) nitrilotriacetate, tetrakis (2,2,6,6-tetramethyl-4-piperidyl )-1,2,3,4-butanetetracarboxylic acid, 1,1'-(1,2-ethanediyl)bis(3,3,5,5-tetramethylpiperazinone).

Oxalamides, for example 4,4'-dioctyloxyoxanilide, 2,2'-dioctyloxy-5,5’-di-t-butyloxanilide, 2,2'-didodecyloxy-5,5'-di-t-butyloxanilide, 2-ethoxy2'-ethyloxanilide, Ν,N'-bis (3-dimethylaminopropyl)20 oxalamide, 2-ethoxy-5-t-butyl-2-ethyloxanilide and its mixture with 2-ethoxy-2'-ethyl-5,4'-di-t-butyloxanilide, mixtures of o- and p-methoxy- and also of o- and pethoxy-disubstituted oxanilides.

Metal deactivators, for example Ν,Ν'-diphenyloxalamide, 25 N-salicylal-N'-salicyloylhydrazine, N,N'-bissalicyloylhydrazine, Ν,N'-bis-(3,5-di-t-butyl-4hydroxyphenylpropionyl)hydrazine, 3-salicyloylamino1,2,3-triazole and bisbenzylideneoxalodihydrazide.

Peroxide-destroying compounds, for example the zinc salt 30 of 2-mercaptobenzimidazole, zincalkyl dithiocarbamates.

Basic costabilizers, for example melamine, polyvinylpyrrolidone, dicyandiamide, triallyl cyanurate, urea derivatives, hydrazine derivatives, amines, polyamines, polyurethanes, alkali metal and alkaline earth metal salts of higher fatty acids, for example calcium stearate, zinc stearate, magnesium stearate, sodium ricinoleate, potassium palmitate, antimony pyrocatecholate or tin pyrocatecholate.

Nucleating agents, for example 4-t-butylbenzoic acid, adipic acid, diphenylacetic acid, benzylidene sorbitol.

Fillers and reinforcing agents, for example calcium carbonate, silicates, glass fibers, asbestos, talc, kaolin, mica, barium sulfate, metal oxides and hydroxides, carbon black, graphite.

Other additives, for example plasticizers, lubricants, emulsifiers, pigments, optical brighteners, flame retardants, antistats, blowing agents.

The polyolefin molding composition of the invention is prepared in a conventional manner. It can be prepared for example by mixing the stabilizers and any further additives by customary methods in the course of the polymerization of the monomers or before or during the molding, or else by applying the dissolved or dispersed compounds to the polymer, with or without subsequent evaporation of the solvent. The stabilizers can also be added to the molding composition to be prepared in the form of a masterbatch which can contain these products in a concentration of about 2.5 to 25% by weight. They may also be added before a possible crosslinking.

To produce calendered films, the molding composition of the invention is processed in a conventional manner for calendered PVC films. To this end, it is first plasticated and homogenized, for example on a roll mill or in a kneader. It is then introduced into the gap between the first and the second roll of a film calender of three to seven, usually four, rolls and drawn out in the plastic state to form a film, which is cooled and wound up. The processing temperature is in general within the range from 170 to 250°C, or higher in exceptional cases, and depends on the melting characteristics of the basic polymer.

Operative Examples 1 to 13 and Comparative Examples A to 5 I The investigations into the processing characteristics of the polypropylene molding compositions compared with a PVC molding composition for calendered films were carried out in a two-roll mill (steel rolls 150 mm in diameter/ temperature 190eC/friction 15/20 rpm) in the form of a dynamic stability test. This test method is employed in particular for assessing the calenderability of PVC mixtures in particular.

Before the dynamic stability test was carried out, the polypropylene molding compositions of Table 1 were each premixed cold and the resulting mixtures were extruded from a single-screw extruder at a barrel temperature of 190°C/210°C/230eC/240eC and then strand granulated.

PVC batch A was prepared by weighing, hot mixing in a hot-cold mixer combination at 120 °C and subsequent cooling to room temperature.

Each test was carried out with 200 g at a time of a molding composition, introduced into a two-roll mill for dynamic stability testing. The test criterion employed for determining the timespan from the time the hide had formed to when the polymer melt began to stick to the hot metal surfaces of the two-roll mill (tack-free time) was the instant at which the 1 nun thick hide can no longer be rolled up with the aid of a wooden spatula from the side to the center of the roll. In addition, after 30 minutes of rolling a sample of 30 g was taken to determine the MFI value. Additionally, in some cases, the MFI value was determined after 5, 10 and 20 minutes.

The test results are summarized in Table 2. It can be seen from the results that, under identical test conditions, a conventionally stabilized polypropylene molding composition (B) begins to stick to the hot roll surfaces after a very short time, compared with a PVC molding composition for calendered films (A), and that the polypropylene hide can no longer be peeled off the rolls. Owing to the thermal stress, the polypropylene molding composition undergoes marked degradation and its viscosity likewise decreases markedly.

It can further be seen that, although the addition of various lubricants delays the onset of sticking of the polypropylene film to the hot metal surfaces of the tworoll mill, the required tack-free processing behavior and a distinct reduction in the degradation of the polymer chains cannot be achieved with these additions.

Only the use of compounds of the formulae I, II, III, IV and V together with one or more phenolic antioxidants brings about the desired release effect in relation to the hot roll surfaces and preserves the high viscosity of the polymer melt required for processing on calendering ranges, i.e. leads to a reduced degradation of the polymer molecules .

Table 1 Comp. A B C D E F Op. 1 Comp. G Batch B + + + + + + + + + (all quantities in phr) 100.0 of suspension PVC, K value 1.5 of octyl tin mercaptide 0.5 of glycerol monooleate 0.5 ester of montanic acid with glycerol 100.0 of polypropylene (MFI 230/2, 0.5 g/10 min) (unstabilized) 0.2 of calcium stearate 0.1 of pentaerythritol tetrakis-[3-(3,5-di-tbutyl-4-hydroxyphenyl) propionate] 0.5 of metal soap-containing multicomponent ester 0.5 of technical grade alkanesulfonate 0.5 of ester of montanic acid with glycerol 0.5 of oxidized polyethylene wax 0.05 of tri (2,4-di-t-butylphenyl) phosphite 0.10 of tri (2,4-di-t-butylphenyl) phosphite 0.10 of tetrakis(2,4-di-tbutylphenyl)-4,4'biphenylene diphosphonite 0.20 of tetrakis(2,4-di-tbutylphenyl)-4,4'biphenylene diphosphonite 0.1 of pentaerythritoltetrakis-[3-(3,5-di-tbutyl-4-hydroxyphenyl) propionate] Table 1 continued Comp. H 100.0 of polypropylene (MFI 230/2, 0.5 g/10 min) (unstabilized) 5 0.2 of calcium stearate 0.1 of glycol bis-3,3-bis-(4'hydroxy-3'-t-butylphenyl)- butanoate I Batch H + 0.1 of glycol bis-3,3-bis-(4'- 10 Op. 5 II + 0.1 hydroxy-3 ' - t-butylphenyl )butanoate of dilauryl thiodipro- pionate 6 II + 0.2 of dilauryl thiodipro- 15 7 II + 0.1 pionate of distearyl thiodipropionate 8 II + 0.2 of distearyl thiodipropionate 20 9 (1 + 0.1 of dioctadecyl disulfide 10 II + 0.2 of dioctadecyl disulfide 11 II + 0.05 of tri (2,4-di-t-butyl- phenyl) phosphite 12 II + 0.10 of tri(2,4-di-t-butyl- 25 phenyl) phosphite 13 100.0 of polypropylene (MFI 230/5, (3 g/10 min) (unstabilized) 0.20 of calcium stearate 30 0.05 of glycol bis-3,3-bis-(4'hydroxy-3' - t-butylphenyl) - butanoate 0.05 of tri{2,4-di-t-butyl- phenyl) phosphite Table 2 - 18 Dynamic stability test on two-roll mill at 190°C and 15/20 rpm Example Tack-free time (min) MFI 230/2 (g/10 min) after a running time of Op.

Op.

Comp.

Comp. 10 20 30 A 45 - - - - B 12 1.9 2.8 5.1 8.5 C 38 1.5 2.6 4.0 10.4 D 30 - - - 18.2 E 23 - - - 13.7 F 18 - - - 10.2 1 38 1.0 1.4 1.7 1.9 2 137 0.8 1.1 1.1 1.7 3 87 - - - 1.4 4 >150 - - - 1.2 G 23 1.8 2.0 4.0 5.3 H 46 1.6 2.0 2.7 3.6 I 144 1.5 1.8 2.0 2.3 5 80 — — — 3.3 6 125 - - - 2.9 7 67 - - - 3.4 8 120 - - - 3.1 9 118 - - - 2.0 10 >150 - - - 1.8 11 >150 0.8 0.9 1.0 1.2 12 >150 0.7 0.7 0.8 0.8 13 140 1.0 1.1 1.1 1.4

Claims (13)

WHAT IS CLAIMED IS:

1. A polyolefin molding composition for producing calendered films, consisting of from 95 to 99.98% by weight of an olefin polymer, from 0.01 to 2.5% by weight of at least one compound of the formula I (I), of the formula II R 1 0 - R 1 P-A-P (II), of the formula III P/ O-CHo CH 2 -0 /P - O-R 3 CH 2 -0 (III), of the formula IV R 4 - (S) x - R 4 (IV) or of the formula V (V), where (R 3 - S - (CH 2 ) 2 - C- 0 - CH 2 ) 4 * C R 1 and R 2 are identical or different and each is hydrogen, methyl, t-butyl, 1,1-dimethylpropyl, cyclohexyl or substituted or unsubstituted phenyl, R 3 is C 8 - to C 22 -alkyl or a radical of the formula R 1 where R and R 2 are each as defined above,

2. A molding composition as claimed in claim 1, wherein the polyolefin is polyethylene, polypropylene, 15 polyisobutylene, polybutene-1, polymethylpentene-1, polyisoprene, polybutadiene, an ethylene-propylene copolymer, a propylene-butene-1 copolymer, a propylene-isobutylene copolymer, an ethylene-butene1 copolymer, a propylene-butadiene copolymer, an 20 isobutylene-isoprene copolymer, an ethylene-alkyl acrylate copolymer, an ethylene-alkyl methacrylate copolymer, an ethylene vinyl acetate copolymer or an ethylene acrylic acid copolymer.

3. A molding composition as claimed in claim 1, wherein 25 the polyolefin is a homopolymer or copolymer of propylene.

4. A molding composition as claimed in claim 1, wherein the phenolic antioxidant is an alkylated monophenol, an alkylated hydroquinone, a hydroxylated 30 thiodiphenyl ether, an alkylidene bisphenol, a benzyl compound, an acrylaminophenol or an ester or amide of β-(3,5-di-t-butyl-4-hydroxyphenyl)propionic acid. - 21 5. A molding composition as claimed in claim 1, wherein the phenolic antioxidant is an ester of bis-3,3bis(4'-hydroxy-3'-t-butylphenyl)butanoic acid.

5. Cyclohexyl or substituted or unsubstituted phenyl, R 3 is C 8 - to C 22 -alkyl or a radical of the formula where R 1 and R 2 are each as defined above, 5 the phenolic antioxidant is an ester of £-(3,5-dit-butyl-4-hydroxyphenyl)propionic acid. 5 R* is C 8 - to C 20 -alkyl or a group of the formula R 4 5 -O-C-(CH2)2-, where R 5 is C8- to C 20 -alkyl, II A is biphenylene, and x is an integer from 1 to 5, 10 and from 0.01 to 2.5% by weight of at least one phenolic antioxidant.

6. A molding composition as claimed in claim 1, wherein

7. A molding composition as claimed in claim 1, wherein the phenolic antioxidant is a benzyl compound.

8. A process for producing calendered films from olefin

9. The process of claim 8, wherein in the molding composition used the polyolefin is a homopolymer or 20 copolymer of propylene.

10. The process of claim 8, wherein in the molding composition used the phenolic antioxidant is an alkylated monophenol, an alkylated hydroquinone, a hydroxylated thiodiphenyl ether, an alkylidene 25 bisphenol, a benzyl compound, an acrylaminophenol or an ester or amide of 0-(3,5-di-t-butyl-4-hydroxyphenyl)propionic acid. - 23 10 R* is C 8 — to C 20 -alkyl or a group of the formula R 5 —0—C— (CH2)2-, where R 5 is C8- to C 20 -alkyl, A is biphenylene, and x is an integer from 1 to 5, 15 and from 0.01 to 2.5% by weight of at least one phenolic antioxidant. 10 polymers by plasticating a polyolefin molding composition and drawing it out in the plastic state on a film calender, which comprises using a molding composition consisting of from 95 to 99.98% by weight of an olefin polymer, 15 from 0.01 to 2.5% by weight of at least one compound of the formula I o ch^ x ch 2 -o^ 0 P \ / c \ z p 0 R x o_CH2 X CH2-0 (ΠΙ), of the formula IV - 22 _ (IV) or of the formula V R 4 - (S) x - R« (V), where (R 3 - s - (CH 2 ) 2 - C- o - ch 2 ) 4 Ϊ c 0 R 1 and R 2 are identical or different and each is hydrogen, methyl, t-butyl, 1,1-dimethylpropyl,

11. A polyolefin molding composition according to claim 1, substantially as hereinbefore described and exemplified.

12. A process according to claim 8 for producing a calendered film, substantially as hereinbefore described and exemplified.

13. A calendered film whenever produced by a process claimed in a preceding claim. Dated this the 6th day of September, 1991