DE1178209B - Process for stabilizing polyolefins or mixtures thereof - Google Patents

Description

Process for stabilizing polyolefins or their mixtures The invention relates to a method for stabilizing filaments and films and other manufactures were malleable crystalline olefin polymers.

It is known that polyolefins during their hot working in In the presence of atmospheric oxygen will suffer some degradation. By addition of suitable protective substances for the polymer, especially during manufacture of objects, this degradation can be limited.

In general, small amounts of phenols are used for this purpose, Amines, sulfur compounds, aminophenols, mercaptans, organic tin compounds, Phosphites or other compounds, such as. B. 2, 6-tert. Butyl-p-cresol, -naphthylamine, p-phenylenediamine, styrenated phenols, 2, 5-di-tert. butylhydroquinone, 2-octyl-4-methoxybenzophenone, 4,4'-thio-bis- (3-methyl-6-tert-butylphenol), 2,2'-methylene-bis- (4-ethyl-6-tert. butylphenol), 4,4'-isopropylidenephenol, phenyl-a-naphthylamine, phenyl-naphthylamine, Polytrimethyldihydroquinoline, methylethylketoxime, cyclohexanone oxime, p-quinonedioxime, N, N'-diphenylethylenediamine, diphenyl-p-phenylenediamine, basic zinc dialkyldithiophosphate, Tris-nonylphenyl-phosphite and nickel-butyl-dithiocarbamate are suitable.

If polyolefins and polyolefin residues are treated with stabilizers, which are known from the prior art, for example also from the French U.S. Patent 1,151,798, then the polyolefin products turn brown while no such discoloration with the stabilizers used according to the invention entry.

It has now been shown that certain organic compounds in polyolefins a clear stabilizing effect against the effects of heat and light as well as against signs of aging, if they are used in quantities of 2% or less, based on the polymer, the crystalline olefin polymer or their mixtures, which are later processed into threads or films and which optionally contain dyes may contain, can be added.

The invention relates to a method for stabilizing Polyolefins or mixtures thereof by an organic containing a cyano group Compound, which is characterized in that, as a stabilizer, 0.02 to 2 percent by weight, based on the polymer, an organic compound is used, which is at least contains a cyanoethyl group CH2CH2CN in the molecule.

The stabilizers used according to the invention become known in Way made by reacting organic compounds that contain active hydrogen atoms contain (e.g. phenols, alcohols, amines, imines, mercaptans, compounds with active Methylene groups or with a —CH2 or also a CH3 group in the adjacent position to a nitrogen atom, an -S02-, aldehyde or. Keto group or halogen derivatives) with acrylonitriles or with other cyanoethylating agents (e.g. CH20H-CH2CN ; (C2H5) 2 = N-CH2-CH2-CN or the salt of CHgJ with jS-cyanoethyl-diethylamine).

It has now been found that the following cyanoethyl compounds are particularly suitable for the desired purpose: #, #, # - tris (β-cyanoethyl) acetophenone Monocyanethyl-dodecylamine CH3 (CH2) 11-NH-CH2CH2CN bis (cyanoethyl) hydroquinone ether Monocyanethyl-octadecylamine CH3 (CH2) 17 - NH - CH2CH2CN Bis-9. 9- (ß-cyanoethyl) fluorene Bis (ß-cyanoethyl) sulfide 9- (β-cyanoethyl) carbazole Cyanoethyl phenol ether Bis (, p-cyanoethyl) amine Tris- (cyanoethyl) -triethanolamine N (CH2CH2OCH2CH2CN) 3 2- (ß-cyanoethyl-oxy) -naphthalene 2, 2. 5. 5-Tetra (β-cyanoethyl) cyclopentanone γ-acetyl-γ-isopropenyl-pimelonitrile Cyanoethyl acetophenone oxime ether Tris4ß-cyanoethyl) nitromethane l-cyanoethyl mercapto-dodecane Preferably the cyanoethyl compounds are mixed with the polyolefin by mechanical working through. But it is also possible to add the cyanoethyl compounds in other ways, such as. B. by mixing the polyolefin with a solution of the cyanoethyl compound in a suitable solvent and then evaporating the solvent or by adding the cyanoethyl compound to the polyolefin at the end of the polymerization.

It is also possible. to achieve the stabilizing effect when the cyanoethyl compounds on the object made from the polymer applies, e.g. B. by immersing the object in a solution or dispersion a cyanoethyl compound and subsequent evaporation of the solvent.

The aforementioned cyanoethyl compounds are associated with the polyolefins Compatible in the molten state and do not cause staining.

In the drawing are the degradation curves at 270 ° C of I. Polypropylene 2. Polypropylene @ 0.2% 4,4'-thio-bis- (6-tert-butyl-p-cresol) 3. Polypropylene 0.2% @ 9- (ß-cyanoethyl) carbazole 4. Polypropylene @ 0.2% bis (ß-cyanoethyl) hydroquinone shown.

The polypropylene used had an intrinsic viscosity of 1.51. a residue after the heptane extraction of 94.5% and an ash content of 0, 23%. @ The determination of the degradation was carried out in such a way that in successive Periods of time the ratio Q / G was determined, where Q is the fluidity index of the Polymers at the applied degradation temperature, determined by flow rate measurements, and G is the melt index determined at 190 ° C.

The curves in the figure show that the polymer 2 is stabilizing with a well-known product such as that used for the thermal stabilization of polyolefins is commonly used, decomposes to a much lesser extent, while the Polymers 1 decomposed quickly. Polymers 3 and 4, which are those specified according to the invention Stabilizers added will degrade to an even lesser extent.

The solution is explained in the following examples.

Example 1 A homogeneous mixture of 49.9 kg of polypropylene ([] = 1.40, determined in tetrahydronaphthalene at 135 ° C., residue after the heptane extraction = 95.9 o / o. Ash content = 0.13%, produced with the help of stereospecific Catalysts) and 0.1 kg of bis-9, 9- (S-cyanoethyl) fluorene, melting point = 118 bis 119 ° C (obtained by reacting 2.1 mol of acrylonitrile with 1 mol of fluorene in dioxane in the presence of Benzyltrimethylammoniumhydroxyd), is in a water mixer Room temperature produced.

The mixture obtained is placed in a test tube in a thermostatic bath melted at 250 ° C. for 10 minutes, an almost colorless melt being obtained.

The mixture is made in a melt-spinning machine under the following conditions spun: screw temperature ........ 260 ° C head temperature ............. 250 ° C Spinneret temperature 240 ° C Spinneret type ................ 60/0, 8-16 Maximum pressure .............. 30 kg / cm2 winding speed ..... 240 m / min.

The continuous thread was made at 160 ° C. in a manner known per se stretched in a ratio of 1: 5. The continuous thread thus obtained possessed the following properties: tensile strength .............. 5, 17 g / den elongation ............. 24% The intrinsic viscosity of this thread is 1.2, while the intrinsic viscosity of a thread made of the same polymer without the addition of the stabilizer is 1.02.

When the stabilized thread is in a heating cabinet at 130 ° C for 5 hours is maintained with air circulation, its properties remain practically unchanged.

Example 2 A homogeneous mixture of 49.9 kg of polypropylene ([R1] = 1.40, determined in tetrahydronaphthalene at 135 ° C., residue after the heptane extraction = 95.9%, ash content = 0.13%, produced with the help of stereospecific Catalysts) and 0.1 kg of tris (cyanethy!) Acetophenone, melting point = 128 to 129 ° C (obtained by reacting 3.1 mol of acrylonitrile with 1 mol of acetophenone in Presence of Benzyltrimethylammoniumhydroxyd), is in a water mixer Room temperature produced.

The mixture obtained is placed in a test tube in a thermostatic bath melted at 250 ° C. for 10 minutes, an almost colorless melt being obtained.

The mixture is made in a melt-spinning machine under the following conditions spun: screw temperature ........ 260 ° C head temperature ........... 250 ° C spinneret temperature 240 ° C type of spinneret ............... 60/0, 8-16 maximum pressure .............. 30 kg / cm2 Winding speed ..... 240 m / min.

The continuous thread was at 160 ° C in a ratio of 1: 5 stretched. The continuous thread thus obtained had the following properties : Tensile strength ................ 5, 55 g / den elongation ................... 21, 8% die The intrinsic viscosity of this thread is 1.2, while the intrinsic viscosity of a thread from the same polymer without the addition of the stabilizer 1.02.

When the stabilized thread is in a heating cabinet at 130 ° C for 5 hours is maintained with air circulation, its properties remain practically unchanged.

Example 3 A homogeneous mixture of 49.9 kg of polypropylene ([] = 1.58, residue after the heptane extraction = 97.9%, ash content = 0.12 ° / 0, produced with the help of stereospecific catalysts) and 0.1 kg of 9- (cyanoethyl) -carbazole, Melting point = 155 ° C. (obtained by reacting 1 mol of carbazole with 3.8 mol of acrylonitrile in the presence of Benzyltrimethylammoniumhydroxyd), is in a water mixer Room temperature produced.

The mixture obtained is placed in a test tube in a thermostatic bath melted at 250 ° C. for 10 minutes, an almost colorless melt being obtained.

The mixture is made in a melt-spinning machine under the following conditions spun: screw temperature .. 260 ° C head temperature ...... 250 ° C spinneret temperature. 240 ° C spinneret type ...... 60/0, 8 # 16 maximum pressure .......... 55 kg / cm2 winding speed ..... 300 m / min.

The continuous thread was at 160 ° C with a ratio of 1: 4, 5 stretched. The continuous thread thus obtained had the following properties : Tensile strength ................ 4, 5 g / den Elongation ............. 27, 8% The intrinsic viscosity this stabilized thread is 1.32, while the intrinsic viscosity of a thread from the same polymer without the addition of the stabilizer 1.09.

When the stabilized thread is in a heating cabinet at 130 ° C for 5 hours is maintained with air circulation, its properties remain practically unchanged.

EXAMPLE 4 A homogeneous mixture is made in a Wern mixer of 49.9 kg of polypropylene (l] = 1.40, residue after the heptane extraction -95.9%, Ash content = 0.13%, produced with the help of stereospecific catalysts) and 0.1 kg of bis (p-cyanoethyl) hydroquinone (obtained by reacting 1 mol of hydroquinone with 2 moles of acrylonitrile in the presence of metallic sodium at 120 to 130-C).

The mixture obtained is placed in a test tube in a thermostatic bath melted at 250 ° C. for 10 minutes, an almost colorless melt being obtained.

The mixture is made in a melt-spinning machine under the following conditions spun: screw temperature ........ 260 C head temperature ............. 250 ° C Spinneret temperature 240 C Spinneret type 60/0, 8 # 16 Maximum pressure 30 kglcm l Winding speed ..... 240 m / min.

The continuous filament was at 160DC in a ratio of 1: 5, 3 stretched. The continuous thread thus obtained had the following properties : Tensile strength ................ 5, 46 g / den elongation ................... 20, 2 "/ o The intrinsic viscosity of this stabilized thread is 1.22, while the intrinsic viscosity of a thread made of the same polymer without the addition of the stabilizer is 1.02.

When the stabilized thread is in a heating cabinet at 130 ° C for 5 hours is maintained with air circulation, its properties remain practically unchanged.

Example 5 A homogeneous mixture of 49.9 kg of polypropylene ([#] = 1.40, residue after heptane extraction = 95.9%, ash content = 0.13% with the help of stereospecific catalysts) and 0.1 kg of tris (cyanoethyl) triethanolamine (Obtained by reacting 1 mole of triethanolamine with 3 moles of acrylonitrile in the presence of sodium methylate) is prepared in a Wern mixer at room temperature.

The mixture obtained is placed in a test tube in a thermostatic bath melted at 250 ° C. for 10 minutes, an almost colorless melt being obtained.

The mixture is made in a melt-spinning machine under the following conditions spun: screw temperature ........ 260 C head temperature ............. 250 C Spinneret temperature 240-C Spinneret type ................ 60 / 0.8 # 16 Maximum pressure .............. 30 kgi'cm 'winding speed ..... 240 m / min.

The continuous thread was at 160 ° C in a ratio of 1: 4, 8 stretched. The so obtained continuous filament had the following properties : Tensile strength ................ 5, 4 g / den elongation .................. 22. 7% die The intrinsic viscosity of this stabilized thread is 1.22, while the intrinsic viscosity of a thread made of the same polymer without the addition of the stabilizer is 1.02.

When the stabilized thread is in a heating cabinet at 130 ° C for 5 hours is maintained with air circulation, its properties remain practically unchanged.

EXAMPLE 6 A homogeneous mixture of 49.9 kg of polypropylene ([#] = 1. 58. Residue after the heptane extraction 97.9%. Ash content = 0.12%, produced with the help of stereospecific catalysts) and 0.1 kg of cyanoethyl-phenol, melting point 62 up to 65-C (obtained by reacting 1 mole of phenol with 1 mole of acrylonitrile in the presence of metallic sodium at 130 to 140 ° C), is in a Wern mixer at room temperature manufactured.

The mixture obtained is placed in a test tube in a thermostatic bath melted at 250 ° C. for 10 minutes, an almost colorless melt being obtained.

The mixture is made in a melt-spinning machine under the following conditions spun: screw temperature ........... 260 ° C head temperature ............. 250 C spinneret temperature. 240-C spinneret type ................. 60 / 0.8 # 16 maximum pressure .............. 40 kg; 'cm'-' winding speed ..... 300 mx'Min.

The continuous thread was at 60C in a ratio of 1 : 4, 3 stretched. The continuous thread thus obtained had the following properties : Tensile strength ................ 3, 94 g / den elongation .................. 31,!. 4% The intrinsic viscosity of this stabilized thread is 1.25, while the intrinsic viscosity of a thread made of the same polymer without the addition of the stabilizer is 1.09.

When the stabilized thread is in a heating cabinet at 130 ° C for 5 hours is maintained with air circulation, its properties remain practically unchanged.

Example 7 89 I n-heptane, 66 g TiCl3, 97 g triethylaluminum and 1051 propylene are put into a 200 liter reactor equipped with a stirrer. brought in.

The mass is stirred for 22 hours at 75 ° C.

After adding a solution of 25 g of 9- (il-cyanoethyl) carbazole in 250 ml of n-butyl alcohol, the mass is centrifuged and dried.

The polypropylene obtained in this way has an intrinsic viscosity of 1.44, cine residue after the heptane extraction of 97.4%, an ash content of 0.19t) / «, and contains the cyanoethyl compound.

The mixture is made in a melt-spinning machine under the following conditions spun: screw temperature. 250 ° C head temperature ........ 230 ° C spinneret temperature 220 ° C type of spinneret ............ 60/0, 8 # 16 maximum pressure ............. 30 kg / cm2 Winding speed ... 250 m / min.

The continuous thread was at 150 ° C in a ratio of 1: 5, 3 stretched. The continuous thread thus obtained had the following properties : Tensile strength ....... 5, 08 g / den elongation .............. 28 ° / o the intrinsic viscosity this thread is 1.28, while the intrinsic viscosity of a thread made from the same Polymers without the addition of the stabilizer 1.02 is.

When the stabilized thread is in a heating cabinet at 130 ° C for 5 hours is maintained with air circulation, its properties remain practically unchanged.

Example 8 Drawn polypropylene filaments from a polymer with an intrinsic viscosity of 1.58, a residue after heptane extraction of 97, 9% and an ash content of 0, 12% are 10 minutes in a 1% solution of 9- (ß-cyanoethyl) carbazole immersed in tetrahydrofuran and then dried.

After this treatment, the threads have the following properties: Tensile strength .......... 3, 21 g / den elongation .. 44, 7% If the stabilized thread is 5 hours at 130 ° C in is kept in a heating cabinet with air circulation, its properties remain practical unchanged.

Example 9 A homogeneous mixture of 49.9 kg of polypropylene ([u] = 17, residue after the heptane extraction = 97%, ash content = 0.22 ° / Oy produced with the help of stereospecific catalysts) and 0.1 kg 2, 2, 5, 5-tetra- (ß-cyanoethyl) -cyclopentanone, Melting point = 175 ° C (obtained by reacting 1 mol of cyclopentanone with 4 mol Acrylonitrile in the presence of Benzyltrimethylammoniumhydroxyd), is in a Wern mixer produced at room temperature.

The mixture is made in a melt-spinning machine under the following conditions spun: screw temperature .. 270 ° C head temperature ............ 250 ° C spinneret temperature ........ 240 ° C spinneret type ................. 60/0, 8 # 16 maximum pressure ............. . 50 kg / cm2 winding speed ..... 340 m / min.

The continuous thread was at 160 ° C in a ratio of 1: 5, 3 stretched. The so obtained continuous filament had the following properties : Tensile strength ............ 4, 55 g / den Elongation ................... 19, 5% The intrinsic viscosity this stabilized thread is 1.22, while the intrinsic viscosity of a thread from the same polymer without the addition of the stabilizer 1.02.

When the stabilized thread is in a heating cabinet at 130 ° C for 5 hours is maintained with air circulation, its properties remain practically unchanged.

Example 10 A homogeneous mixture of 49.9 kg of polypropylene ([X7] = 1.7, residue after the heptane extraction = 97%, ash content = 0.22% with the help of stereospecific catalysts) and 0.1 kg of y-acetyl-y-isopropenyl-pimelonitrile, Melting point = 116 ° C. (obtained by reacting 1 mole of mesityl oxide with 2 moles of acrylonitrile in the presence of Benzyltrimethylammoniumhydroxyd), is in a water mixer Room temperature produced.

The mixture is made in a melt-spinning machine under the following conditions spun: screw temperature ...... 270 ° C head temperature ........... 240 ° C spinneret temperature 230 ° C spinneret type 60/0, 8-16 maximum pressure ............ 45 kg / cm2 winding speed ... 340 m / min.

The continuous thread was at 160 ° C in a ratio of 1: 5, 3 stretched. The continuous thread thus obtained had the following properties : Tensile strength ............ 4, 72 g / den elongation .......... 21, 7 ° / o the intrinsic viscosity this stabilized continuous thread is 1.26, while the intrinsic viscosity of a thread made of the same polymer without the addition of the stabilizer is 1.02.

When the stabilized thread is in a heating cabinet at 130 ° C for 5 hours is maintained with air circulation, its properties remain practically unchanged.

Example 11 A homogeneous mixture of 49.9 kg of polypropylene ([n] = 1.42, residue after the heptane extraction = 96.3%, ash content = 0.1%, produced with the help of stereospecific catalysts) and 0.1 kg of cyanoethyl acetophenone oxime, Melting point = 44 ° C (obtained by reacting 1 mol of acetophenone oxime with 1 mol Acrylonitrile in the presence of Benzyltrimethylammoniumhydroxyd), is in a Wern mixer produced at room temperature.

The mixture is made in a melt-spinning machine under the following conditions spun: screw temperature .......... 230 ° C head temperature ............ 230 ° C Spinneret temperature 220 ° C Type of spinneret ......... 60/0, 8-16 Maximum pressure .............. 20 kg / cm2 winding speed ..... 250 m / min.

The continuous thread was at 145 ° C in a ratio of 1: 5, 3 stretched. The continuous thread thus obtained had the following properties : Tensile strength ................ 5 g / den Elongation ................... 15.3% The intrinsic viscosity this thread is 1.29, while the intrinsic viscosity of a thread made of the same Polymers without the addition of the stabilizer 1.03.

When the stabilized thread is in a heating cabinet at 130'C for 7 hours is maintained with air circulation, its properties remain practically unchanged.

Example 12 A homogeneous mixture of 49.9 kg of polypropylene ([#] = 1.42, residue after the heptane extraction = 96.3%, ash content = 0.1%, produced with the help of stereospecific catalysts) and 0.1 kg of tris (cyanoethyl) nitromethane, Melting point = 114 ° C (obtained after a modification of the method of B r u s o n and R i e n e r, "J. A. C. S.", 1943, p. 23; U.S. Patent 2361259 [Bruson] by reacting 1 mole of nitromethane with 3.1 mole of acrylonitrile in the presence of sodium methylate; after standing overnight, the mass was treated with dilute hydrochloric acid acidified, the tris (cyanoethyl) nitromethane was made by adding ethyl ether precipitated and then recrystallized from alcohol), is in a Wern mixer Room temperature produced.

The mixture is made in a melt-spinning machine under the following conditions spun: screw temperature ........ 230 "C head temperature ............. 230'C Spinneret temperature 220 ° C Spinneret type 60/0, 8-16 Maximum pressure .............. 20 kg / cm2 winding speed ..... 250 m / min.

The continuous thread was at 145 ° C in a ratio of 1: 5, 3 stretched. The continuous thread thus obtained had the following properties : Tensile strength ................ 5.1 g / den elongation .................. 15.6 "/ o the The intrinsic viscosity of this stabilized thread is 1.29, while the intrinsic viscosity of a thread made of the same polymer without the addition of the stabilizer is 1.03.

When the stabilized thread is 7 hours at 130 ° C in a heating cabinet is held with air circulation. its properties remain practically unchanged.

Example 13 In a Wern mixer at room temperature a homogeneous mixture of 45 kg polypropylene (intrinsic viscosity = 126, ash content = 0.036%, Residue after the heptane extraction = 93.7%. made with the help of stereospecific Catalysts) and 4.9 kg of polybutene (obtained with Help of stereospecific catalysts) and 0.1 kg of 9- (ß-cyanoethyl) carbazole (obtained by reaction of 1 mol of carbazole with 3.8 moles of acrylonitrile in the presence of benzyltrimethylammonium hydroxide).

The mixture was made in a melt-spinner under the following conditions spun: screw temperature ........ 220 ° C head temperature ............. 210 ° C Spinneret temperature ........ 200 ° C Spinneret type 601/0, 8-16 Maximum pressure .............. 18 kg / cm2 winding speed ..... 320 m / min.

The threads were steamed at 160 ° C in a ratio stretched from 1: 5, 3. The properties of the fibers obtained are as follows: Tensile strength ................ 4, 9 g / den Elongation ................... 22 ° / 0 The stabilization against degradation during processing that of the mixture by adding the cyanoethyl compound was awarded, it follows that the intrinsic viscosity of the thread is 1.27, while that of a thread. obtained from the same polymer mixture, but without Addition of the stabilizer is 0.98.

The stabilized thread remains practical in its properties unchanged when placed in a heating cabinet with air circulation -5 hours at 130 ° C is heated.

Example 14 In a Wern mixer at room temperature a homogeneous mixture of 49.9 kg polyethylene with a molecular weight of approximately 50000 (produced with the help of stereospecific catalysts) and 0.1 kg of di -, - acetyl -, - isopropenylpimelonitrile (Obtained by reaction of 1 mol of mesityl oxide with 2 Mo) of acrylonitrile in the presence of benzyltrimethylammonium hydroxide).

The mixture was made in a melt-spinner under the following conditions spun: Spinneret temperature ..... 190 C Spinneret type ... 1 0. 8 16 Maximum pressure ......... 17 kg / cm2 unwinding speed 175 m Min.

The continuous filaments were steamed at 160 C in cincm ratio of 1: 5, 3 drawn. The properties of the fibers obtained are the following: tensile strength ........... 3. 2 g / the elongation ...................... 27% The stabilization against degradation during processing that the mixture through Addition of the cyanoethyl compound was compared. results from the fact that the moieku) argew) cht of the thread is 42,000, while that of a thread obtained from the same polymers, but without the addition of the stabilizer, is 27,000.

The stabilized thread remains practically unchanged in its properties when it is heated to 100 ° C. for 5 hours in a heating cabinet with air circulation. For comparison, an attempt was made to stabilize polypropylene with 0.5% 2.5-dichlorophenylazocyanacetate, ie it became the connection the formula used as a stabilizing agent, which is cited in French Patent 1,151,798.

The mixture of this stabilizer and polypropylene was made pressed and the threads obtained with a stretching ratio of 1: 5, 3 stretched. The properties of the thread obtained were as follows: Tensile strength ................ 5, 4 g / den elongation ................... 23, 6% intrinsic viscosity of the thread ............... 1, 15 of the starting polypropylene 1, 52 The tensile strength of the stabilized thread was in an air-circulating oven at 130 ° C for 5 hours after exposure to heat reduced to 43% of the initial value. In contrast, the properties of the invention stabilized poly propylene threads practically not at all in such a test decreased. Another disadvantage of the known stabilizer is that that the thread stabilized with it browns already after 10 minutes of heating at 250 ° C becomes, while with a stabilization according to the method according to the invention none The treated threads change color.

Claims (2)

Claims: 1. Process for stabilizing polyolefins or mixtures thereof with an organic compound containing a cyano group, characterized in that 0.02 to 2 percent by weight is used as the stabilizer on the polymer, an organic compound is used that has at least one Contains cyanoethyl group-CH2-CH2-CN in the molecule. 2. The method according to claim 1, characterized in that the stabilizing takes place before or after the deformation of the polyolefin. Documents considered: French patent specification No. 1 151 798.