PROCESS FOR PREPARING HOMOGENEOUS COMPOSITIONS OF OLEFINIC POLYMERS IN THE FORM OF GRANULES AND OF VARIOUS ADDITIVES

Abstract: Process for preparing homogeneous compositions of olefinic polymers in flakes and of additives, suitable for the direct transformation into manufactured articles, consisting in mixing the polymer with the additive and with a third component, acting as coupling agent, selected from the class consisting of liquid or solid paraffinic compounds having a linear or branched chain, comprising from 2 to 500 carbon atoms, optionally containing one or more polar functional groups, which is employed in the pure state or in solution in hydrocarbon solvents, as the rate of 0.01-5% by weight refer­ red to the total of the mix.

Description: "PROCESS FOR PREPARING HOMOGENEOUS COMPOSITIONS OF OLE FINIC POLYMERS IN THE FORM OF GRANULES AND OF VARIOUS ADDITIVES" This invention relates to compositions containing additiv es, obtained from polyolefins in the form of freeflowing particles (flakes) and to the process for preparing same. For preparing manufactured articles of polyolefins, pigmented, stabilized and generally containing compounds modifying the characteristics of the articles, the Applicant and others have suggested processes based on the admixture of the polyolefins in powder with the additives, and on the successive transformation into granules by extrusion in the molten state. The granulated products are then utilized for being transformed into textile fibres, films, fibrillated films, fibrils, spun-bonded, by extrusion, and into plastic articles by extrusion, blow molding, coating, thermoforming-molding, calendering, roto-molding and the like. The processes based on the mixing of powdered polyolefins with additives and on the successive granulation involve complex technological operations, which are necessary when it is operated-with very fine powders. The polyolefins, however, can be prepared also in the farm of granules, the so-called flakes, according to what described by C.W. Hock in Polymer Sci., 4, 3055 (1966), and in several patents in the name of the Applicant and of others. Such polymeric products are obtained directly in polymerization processes in suspension and consist of particles having an average size larger than 150 microns. These polyolefinic flakes can be directly transformed into additive-containing articles, after a simple mixing of the polyolefins with the additives, and excluding the granulation step, as this would cause non-homogeneous distrib tions of the additives in the polyolefins and difficulties in the transformation operations. The Applicant has now found a process -. which is the object of the present invention - for preparing additional polyolefinic flakes, which consists in mixing the polyolefins in flakes with the additives, in the presence of a small amounts of a third component (a coupling agent) having the function of promoting a homogeneous distribution of the additives on the flakes' surfaces, binding then to the latter and making possible a direct transformation into manufactured articles, without any granulation step. The coupling agents suited to the use according to this invention are selected from the class consisting of paraffinic compounds, having a linear or branched chain, either liquid or solid, containing 2 to 500 carbon atoms, in particular vaseline oil, paraffin waxes, oligomers of propylene and ethylene, low molecular weight polypropylenesand the like, which are employed either in the pure state or in solution in hydrocarbon solvents. It has been also found - and this is another feature of the present invention - that the paraffin compounds may contain one or more polar functional groups. In such case the affinity between the coupling agent and the functional groups of the additives improves. Paraffinic compounds containing polar groups particularly useful according to this invention are the ones comprised in the following general formula: R-X wherein X is a linear or branched alkyl radical, containing 12 to 30, preferably 12 to 18, carbon atoms, X may be: a) - OH b) - COOH or corresponding salts of alkaline metals c) - NR'-R" where R' and R", either like or unlike each other, are hydrogen or alkyls having 1 to 12 carbon atoms d) - O(CH CH O) -H, -0/ CH(CH )CH 0 / -H where n = 1-50 2 2 - 3 2-n preferably 4-20 EMI4.1 where n and n', either like or unlike each other, are comprised between 0 and 50, at least one being diffe rent from 0 f) - OCOR"' where R"' is an alkyl containing hydroxyl groups, in particular it may be a radical deriving from polyols such as ethylene glycol, glycerine, pentaerythritol. The compounds utilized as coupling agents according to this invention are employed in amounts ranging from 0.01% to 5% by weight referred to the total compounded polymer. The additives employable according to the present invention include stabilizers, opacifiers, organic and inorganic pigments, blowing agents, lubricants, antistatic agents, dyeing modifiers, hydrophilising agents and the like, either alone or in admixture with one another. As polyolefins in flakes use is made of the olefinic crystalline polymers, prepared by means of stereospecific cata lysts, more particularly the propylene polymers having prevailing isotactic macromolecules and the ethylene-propylene crystalline copolymers prevailing containing propylene, either of the random type or in blocks. A particularly advantageous method of embodying this invention consists in preparing a concentrated mix of granular polymer, with a relatively high content of additive and of coupling agent, which is then mixed with the polymer as such in a suitable amount, in order to obtain the desired polymeric composition. Wide variations and modifications may be brought to the present invention, without departing however from the spirit and the objects thereof. The following examples are given to illustrate this invention, without being however a limitation thereof. EXAMPLE 1 - Polypropylene in flakes 1.780 kg - vaseline oil 0.020 kg - "Graftolo" Yellow RCL (C.I. Pig ment Yellow 83) 0.200 kg were introduced into a 10-liter Henschell mixer. Mixing was carried out at 250C for 5 minutes. The polypropylene in flakes utilized exhibited a melt index = 12, a residue to the extraction with heptane = = 97.5%, an ash content = 75 ppm, and apparent density = = 0.51 and the following granulometric distribution: 5840 P = 4.4 % 420-840 yu = 23.0 % 250-420 P = 55.4 % 177-250 P = 8.5 % 149-177 JU = 3.2 % 74-149 P = 5.5 % < 74 = O % The concentrated mix was fully homogeneous, as resulted from the absence of any crumbs and deposits on the mixer walls. Photographic enlargements of the mix revealed a uniform distribution of the pigment on the surface of the polymer granules, unlike what occurs with a polymer mix not containing vaselin oil. 0.030 kg of concentrated mix were diluted by mixing in a lO-liter quick mixer of the Henschell-type, with 2.970 kg of polypropylene flakes, to obtain a pigment concentration of 0.1%. To check the influence exerted by the coupling agent on the homogeneous distribution of the pigment and on its intensity, as well as to check the influence thereof on the colour stability to heat degradation, small plates were prepared with the dilute mix. The 1-mm thick plates were prepared in a Carver press by heating for 15 minutes to temperatures of 2000C, 2400C, 2600C, 2800C. In all the samples the pigment turned out to be perfectly stable to heat degradation. EXAMPLE 2 - Polypropylene in flakes - 1.780 kg - vaseline oil 0.020 kg - thermostable Red BRA (C.I. Pigment Red 144) 0.200 kg were introduced into a 10-liter mixer, Henschell-type. Mixing was conducted at 250C for 5 minutes. The polypropylene in flakes utilized exhibited a melt index = 12, a residue to the extraction with heptane = 97.5%, ashes = 75 ppm, an apparent density = 0.51 and the following granulometric distribution: > 840 y = 4.4 % 420-840 ji = 23.0 0 250-4?0 X = 55.4 S 177-250 P = 8.5 0 149-177 P = 3.2 % 74-149 P = 5.5 % 4 74 r = O S The concentrated mix was fully homogeneous, as was proved by the absence of crumbs and deposits on the mixer walls. Photographic enlargements of the mix showed a uniform distribution of the pigment on the surface of the polymer granules, unlike what happens with a polymer mix not contain ing vaseline oil, in which the dyeing yield is by far lower. 0.030 kg of concentrated mix were diluted by mixing in a 10-liter quick mixer of the Henschell-type, with 2.970 kg of polypropylene flakes, to obtain a pigment concentration of 0.1%. To check the influence exerted by the coupling agent on the homogeneous distribution of the pigment and on its intensity, as well as to check the influence thereof on the colour stability to thermal degradation, small plates were prepar-ed with the dilute mix. The l-mm thick plates were prepared in a Carver press, by heating for 15 minutes to temperatures of 2000C, 2400C, 26O0C, 2800C. In all the samples the pigment proved to be thoroughly stable to heat decomposition. The dilute mix was directly fed to a melt spinning device. Spinning and successive stretching were carried out under the following working conditions: - temperature of the head 2300C - temperature of the spinneret 2300C - temperature of the screw 24O0C - spinneret type (number of holes/dia meter/height) 40/0.8/4 - max. pressure 26 kg/cm - winding speed 400 m/min. - stretching temperature 1300C - stretching medium vapour - stretching ratio 1 : 3.3 The resulting fibres exhibited a uniform pigmentation and the following characteristics: - count 17 dtex - tenacity 3.3 g/dtex - elongation 62 % EXAMPLE 3 Into a 10-liter mixer of the Henschell-type, the following products were introduced: - polypropylene in flakes 1.340 kg - vaseline oil 0.060 kg - "Graftolo" oxide red EOR 0.600 kg Mixing was carried out at 250C for 5 minutes. The utilized polypropylene in flakes exhibited a melt in dex = 12, a residue to the extraction with heptane = 97.5, ashes = 75 ppm, an apparent density = 0.51, and the following granulometric distribution: .840 = 4.4 % 420-840 = 23.0 d 250-420 P = 55.4 % 177-250 /u = 8.5 % 149-177 P r. = 3.2 % 74-149 P = 5.5 % 4 74 = 0 % The concentrated mix was quite homogeneous, as proved by the absence of crumbs and deposits on the mixer walls. Photographic enlargements of the mix revealed a uniform distribution of the pigment on the surface of the polymer granules unlike what happens with the polymer mix not containing vaseline oil, in which the dyeing yield is by far lower. 0.010 kg of concentrated mix were diluted, by mixing in a 10-liter quick mixer Henschell-type, with 2.990 kg of polypropylene flakes, to obtain a pigment concentration of 0.1S. To check the influence of the coupling agent on the homogeneous distribution of the pigment and on its intensity, as well as to check the influence thereof on the colour stability to thermal degradation, small plates were prepared with the dilute mix. The 1-mm thick plates were prepared in a Carver press, by heating for 15 minutes to temperatures of 2000C, 2400C, 2600C, 2800C. In all the samples the pigments resulted to be fully stable to heat degradation. EXAMPLE 4 - Propylene in flakes 1.780 kg - paraffin, melting point = 51-530C . 0.020 kg - Thermostable Red BRA (C.I. Pigment Red 144) 0.200 kg were introduced into a 10-liter mixer, Henschell-type. Mixing was conducted at 250C for 5 minutes. The polypropylene in flakes employed exhibited a melt index = 12, a residue to the extraction with heptane = = 97.5%, an ash content = 75 ppm, an apparent density = = 0.51, and the following granulometric distribution: > 840 = 4.4 % 420-840 = 23.0 % 250-420 = 55.4 % 177-250 P = 8.5 % 149-177 P = 3.2 % 74-149 P = 5.5 % ( 74 r = 0 % The concentrated mix was completely homogeneous, as resulted from the absence of crumbs and deposits on the mixer walls, and from the uniform pigment coating on the polypropylene flakes. EXAMPLE 5 - Polypropylene in flakes 1.780 kg - vaseline oil 0.020 kg - pentaerythritoltetra-3-(3 , 5-di-tert butyl- -4-hydroxyphenyl ) -propionate 0.200 kg were introduced into a 10-liter mixer of-the Henschell-type. Mixing was carried out at 250C for 5 minutes. The polypropylene in flakes utilized exhibited a melt index = 12, a residue to the extraction with heptane = 97.5%, an ash content = 75 ppm, an apparent density = 0.51, and the following granulometric distribution: > 840 = 4.4 % 420-840 = 23.0 % 250-420 = 55.4 % 177-250 = 8.5 % 149-177 r = 3.2 % 74-149 = 5.5 % ( 74 r = 0 % The concentrated mix is fully homogeneous, as was proved by the absence of crumbs and deposits on the mixer walls. Photographic enlargements of the mix revealed a uniform distribution of the additive on the surfaces of the polymer granules unlike what happened with the polymer mix not containing vaseline oil. EXAMPLE 6 - Polypropylene in flakes 1.780 kg - vaseline oil 0.020 kg - 2-tert.butil-2/ 4-hydroxy-2,3,5,5- -tetramethylbenzil /malonate of 2,2,6,6-tetramethyl-4-piperidyl 0.200 kg were introduced into a 10-liter mixer, Heschell-type. Mixing was conducted at 250C for 5 minutes. The polypropylene in flakes employed exhibited a melt index = 12, a residue to the extraction with heptane = 97.5%, an ash content = 75 ppm, an apparent density = 0.51, and the following granulometric distribution: 840 840 = 4.4 % 420-840 V = 23.0 % 250-420 = 55.4 % 177-250 P = 8.5 % 149-177 P = 3.2 % 74-149 = 3.5 % 7 < 74 = 0 % The concentrated mix was completely homogeneous, as resulted from the absence of crumbs and deposits on the mixer walls. From photographic enlargements of the mix it was possible to notice a uniform distribution of the additive on the surfaces of the polymer granules unlike what happens with a polymer mix not containing vaseline oil. EXAMPLE 7 - Polypropylene in flakes 1.780 kg - N,N-bis-(polyoxyethylene)-n.dodecyl amine (with about 20 units (CH2CH20) 0.020 kg - "Graftolo" Yellow RCL (C.I. Pigment Yellow 83) 0.200 kg were introduced into a 10-liter mixer, Henschell-type. Mixing was conducted for 5 minutes at 250C. The employed polypropylene in flakes exhibited a melt index = 12; a residue to the extraction with heptane = 97.5%, an ash content = 75 ppm, an apparent density = 0.51, and the following granulometric distribution: > 840 P = 4.4 % 420-840 = 23.0 % 250-420 r = 55.4 % 177-250 P = 8.5 % 149-177 P = 3.2 % 74-149 X = 5.5 % ( 74 fi = O The concentrated mix was thoroughly homogeneous, as resulted from the absence of crumbs and deposits. on the mixer - walls. Photographic enlargements of the mix revealed a uniform distribution of the pigment on the surfaces of the polymer granules unlike was happens with a polymer mix not containing polyoxy-ethylene-dodecylamine, in which the dyeing yeld is by far lower. 0.030 kg of concentrated mix were diluted by mixing in a 10-liter slow mixer of the Battagion-type with 2.970 kg of polypropylene flakes to obtain a pigment concentration of 0.1%. To check the influence of the coupling agent on the homogeneous distribution of the pigment and on its intensity, as well as to check the influence thereof on the colour stability to termal degradation, small plates were prepared with the dilute mix. The 1-mm thick plates were prepared in a Carver press, by heating for 15 minutes to temperatures of 2O00C, 24O0C, 26O0C, 28O0C. In all the samples the pigment resulted fully stable to thermal degradation. The dilute mix was directly fed to a melt spinning device. Spinning and successive stretching were carried out under the following operative conditions: - temperature of the head 2300C - temperature of the spinnert 2300C - temperature of the screw 2400C - spinneret type (number of holes/ diameter/height) 40/0.8/4 - maxi pressure 27 kg/cmê - winding speed 400 m/mi-n - stretching temperature 1300C - stretching medium - vapour - stretching ratio 1:3.4 The fibres so obtained exhibited a uniform pigmentation and the following characteristics: - count 17 dtex - tenacity 3.2 g/dtex - elongation 67 % EXAMPLE 8 Into a Henschell-type mixer having a capacity of 10 liters, the following was introduced: - polypropylene in flakes 1.780 kg - N,N-bis-(polyoxyethylene)-n.dodecyl amine 0.020 kg - thermostable Red BRA (C.I.-Pigment Red 144) 0.200 kg. Mixing was conducted at 250C for 5 minutes. The polypropylene in flakes employed exhibited a melt index = 12, a residue to the extraction with heptane = 97.5, an ash content = 75 ppm, an apparent density = 0.51 and the following granulometric distribution: > 840 r = 4.4 % 420-840 P = 23.0 % 250-420 T = 55.4 % 177-250 Z = 8-5 % 149-177 f = 3.2 % 74-149 / = 5.5 % < 74 U = O The concentrated mix was completely uniform, as resulted from the absence of crumbs and deposits on the mixer walls. Photographic enlargements of the mix revealed a uniform distribution of the pigment on the surfaces of the polymer granules unlike what happens with a polymer mix not containing polyoxyethylene-dodecylamine, in which the dyeing yield is much lower. 0.030 kg of concentrated mix were diluted by mixing in a slow mixer, Battagion-type, having a 10-liter capacity, with 2.970 kg of polypropylene flakes, to obtain a pigment concentration of 0.1%. To check the influence of the coupling agent on the homogeneous distribution of the pigment and on its intensity, and also to check the influence thereof on the colour stability the thermal degradation, plates were prepared with the dilute mix. The 1-mm thick plates were prepared in a Carver press, by heating for 15 minutes to temperatures of 2000C, 2400C, 2600C, 2800C. In all the samples the pigment. appeared fully stable to ther mal decompositions. ELAblPLE 9 Into a Henschell mixer having a 10-liter capacity, -polypropylene in flakes 1.340 kg -N ,N-bis(polyoxyethylene)-n.dodecyl- aminc 0.060 kg - "Graftolo" oxide Red EOR 0.600 kg were introduced. Mixing was effected at 250C for 5 minutes. The employed polypropylene in flakes exhibited a melt index = 12, a residue to the extraction with heptane = 97.5%, an ash content = 75 ppm, an apparent density = 0.51 and the following granulometric distribution: > 840 f = 4.4 420-840 f = 23.0 % 250-840 ji = 55.4 % 177-250 JU = 8.5 149-177 / = 3.2 74-149 JU = 5.5 ( 74 f = O The concentrated mix was completely homogeneous, as resulted from the absence of crumbs and deposits on the mixer walls. Enlarged photographs of the mix revealed a uniform distribu tion of the pigment on the surface of the polymer granules unlike what happens with a polymer mix not containing polyo xyethylene-dodecylamine, in which the dyeing yield is much lower. 0.010 kg of concentrated mix were diluted by mixing in a slow mixer, Battagion-type, having a 10-liter capacity, with 2.990 kg of polypropylene flakes, to obtain a pigment concen tration of 0.1. To check the influence of the coupling agent on the homogeneous distribution of the pigment and of its intensity, as well as to check the influence thereof on the colour stability to thermal degradation, plates were prepared with the dilute mix. The 1-mm thick plates were prepared in a Carver press, by heating for 15 minutes to tcmperatures of 200 C, 2400C, 2600C, 2800C. In all the samples the pigment resulted perfectly stable to thermal degration. EXAMPLE low A Henschell-type mixer having a 10-liter capacity was charged with - polypropylene in flakes 1.780 kg -'N,N-bis-(polyoxyethylene)-n.octa- decylamine (containing about 20 units (CH2CH20) 0.020 kg - thermostable Red BRA (C.I. Pigment - -Red 144) 0.200 kg Mixing was carried out at 250C for 5 minutes. The polypropylene in flakes utilized exhibited a melt index = 12, a residue to the extraction with heptane = 97.5f, an ash content = 75 ppm, an apparent density = 0.51, and the following granulometric distribution > 840 = 4.4 % 420-840 = 23.0 % 250-420 = 55.4 % 177-250 P = 8.5 % 9 149-177 = 3.2 % 74-149 = 5.5 % < 74 r = O The concentrated mix was fully homogeneous, as resulted from the absence of crumbs and deposits on the mixer walls, and from the uniform pigment coating on the polypropylene flakes. EXAMPLE 11 Into a Henschell-type mixer, having a 10-liter capacity, - polypropylene in flakes 1.780 kg - N,N-bis-(polyoxyethylene)-n.dodecylamine 0.020 kg - azodicarbonamide 0.200 kg were introduced. Mixing was conducted at 250C for 5 minutes. The employed polypropylene in flakes exhibited a melt index = 12, a residue to the extraction with heptane = = 97.5%, an ash content = 75 ppm, an apparent density = = 0.51, and the following granulometric distribution > 840 P = 4.4 % 420-840 P = 23.0 % 250-420 = 55.4 % 177-250 = 8.5 % 149-177 = 3.2 % 74-149 P = 5.5 % 74 )1:.= 0 The concentrated mix was completely hompgeneous, as resuled from the absence of crumbs and deposits on the mixer walls. Enlarged photographs of the mix revealed a uniform distribution of the blowing agent on the surfaces of the polymer granules, unlike what happens with a polymer mix not containing polyoxyethylene-dodecylamine. 0.300 kg of a concentrated mix were diluted by mixing in a Battagion slow mixer having a 10-liter capacity, with 2.700 kg of polypropylene flakes, to obtain a concentration of the blowing agent of 1%. To check the influence of the coupling agent on the homogeneous distributio of the blowing agent and on the trend of its thermal degradation, plates were prepared with the dilute mix. 2-mm thick plates were prepared in a Carver press by heating for 5 minutes to a temperature of 2400C. The dimension and the distribution of the pores formed during the thermaldegradaton of the blowing agent, detected by photographic enlargements, proved a homogeneous distribution on the blowing agent in the polymer containing polyoxyethylene-dodecylamine, unlike what happnes in the sam ple without coupling agent. EXAMPLE 12 Into a 10-liter mixer, Henschell-type, the following was introduced - polypropylene in flakes 1.780 kg - N,N-bis-(polyoxyethylene)-n.-dodecylamine 0.020 kg - pentaerythritoltetra-3 (3,5-di-tert. butyl-4-hydroxyphenyl)propionate 0.200 kg Mixing was carried out at 250C for 5 minutes. The polypropylene in flakes utilized exhibited a melt index = 12, a residue to the extraction with heptane = = 97.5%, an ash content = 75 ppm, an apparent density = = 0.51, and the following granulometric distribution > 840 p = 4.4 % 420-840 P = 23.0 % I 250-420 P = 55.4 177-250 = 8.5 % 149-177 = 3.2 % 74-149 = 5.5 % 4 74 JI O % The concentrated mix was thorougly homogeneous, as resuled from the absence of crumbs and deposits on the mixer walls. Enlarged photographs of the mix revealed a uniform distribution of the stabilizer on the surfaces of the polymer granules, unlike what occurs with a polymer mix not containing polyoxyethylene-dodecylamine. EXAMPLE 13 A 10-liter mixer, Henschell-type, was charged with - polypropylene in flakes - 1.780 kg - N,N-bis-(polyoxyethylene)-n.dodecyl amine 0.020 kg - Ni-2,2'-thiobis(4-tert.octyl)-phenol ate-n,butylamine 0.200 kg Mixing was carried out at 250C for 5 minutes. The polypropylene in flakes employed exhibited a melt index = 12, a residue to the extraction with heptane = = 97.5, an ash content = 75 ppm, an apparent density = = 0.51 and the following granulometric distribution > 840 = 4.4 % 420-840 = 23.0 % 250-420 = 55.4 % 177-250 r = 8.5 % 149-177 = 3.2 % 74-149 = 5.5 %0 < 74 P = O % The concentrated mix was completely homogeneous, as resulted from the absence of crumbs and deposits on the mixer walls. Enlarged photographs of the mix revealed a uniform distribution of the stabilizer on the surfaces of the polymer granules, unlike what happens with a polymer mix not containing polyoxyethylene-dodecylamine. EXAMPLE 14 Into a Henschell-type mixer having a 10-liter capacity, the following was introduced - polypropylene in flakes 1.780 kg - N,N-bis(polyoxyethylene)n.dodecyl amine 0.-020 kg - 2-tert . butyl-2-/ 4-hydroxy-3,3,5,5- tetramethylbenzyl ]malonate of 2,2,6,6-tetramethyl-4-piperidyl 0. 200 kg Mixing was effected at 250C for 5 minutes. The polypropylene in flakes employed exhibited a melt index = 12, a residue to the extraction with heptane = = 97.5%, an ash content = 75 ppm, an apparent density = = 0.51 and the following granulometric distribution > 840 P = 4.4 % 420-840 P = 23.0 % 250-420 P = 55.4 % 177-250 = 8-5 % 149-177 1 = 3.2 % 74-149 P = 5.5 % ( 74 O The concentrated mix was thorougly homogeneous, as result ed from the absence of crumbs and deposits on the mixer walls. Enlarged photographs of the mix showed a uniform distribution of the stabilizer on the surface of the polymer granules, unlike what occurs with a polymer mix not containing polyoxyethylene-dodecylamine. EXAMPLE 15 Into a Henschell-type mixer having a 10-liter capacity, the following was introduced - polypropylene in flakes 1.780 kg - ethyelene glycol monolaurato 0.020 kg - pentaerythritoltetra-3-(3,5-di-tert. .butyl-4-hydroxyphenyl)-propionate 0.200 kg Mixing was effected at 250Cfor 5 minutes. The polypropylene in flakes employed exhibited a melt index = 12, a residue to the extraction with heptane = = 97.5f, an ash content = 75 ppm, an apparent density = = 0.51, and the following granulometric distribution > 840 = 4.4 % 420-840 = 23.0 % 250-420 P = 55.4 % 177-250 = 8.5 % 149-177 = 3.2 % 74-149 A = 5.5 < 74 X = O The concentrated mix was completely homogeneous, as resul ted from the absence of crumbs and deposits on the mixer walls. Enlarged photographs of the mix revealed a uniform distri bution of the stabilizers on the surfaces of the polymer granules, unlike what happens with a polymer mix not containing ethylene glycol monolaurate. EXAMPLE 16 A Henschell-type 10-liter mixer charged with - polypropylene in flakes 1.780 kg - glycerine monostearate - 0.020 kg - pentaerythritoltetra-3(3,5-di-tert.bu tyl-4-hydroxyphenyl-propionate) 0.200 kg Mixing was carried out at 250C for 5 minutes. The polypropylene in flakes employed exhibited a melt index = 12, a residue to the extraction with heptane = = 97.5%, an ash content = 75 ppm, an apparertdensity = = 0.51 and the following granulometric distribution > 840 ji = 4.4 % 420-840 tz. = 23.0 % 250-420 P = 55.4 % 177-250 = 8.5 % 149-177 = 3.2 % 74-149 f = 5.5 % < 74 = 0 The concentrated mix was completely homogeneous, as resulted from the absence of crumbs and deposits on the mixer walls. Enlarged photographs of the mix revealed a uniform distribution of the stabilizers on the surfaces of the polymer granules, unlike what happens a polymer mix not containing glycerine monostearate. EXAMPLE 17 A 10-liter mixer, Henschell type, was charged with - polypropylene in flakes 1.780 kg - ethylene glycol monolaurate 0.020 kg - Ni-2,2'-thiobis(4-tert.octyl)phenolate- n.butylamine 0.200 kg Mixing was carried out at 250C for 5 minutes. The polypropylene in flakes employed exhibited a melt index = 12, a residue to the extraction with heptane = = 97.5%, an ash content = 75 ppm, an apparent density = = 0.51 and the following granulometric distribution > 840 = 4.4 % 420-840 g=23.0 % 250-420 =55.4 % 177-250 = 8.5 % 149-177 = 3.2 % 74-149 = 5.5 % 474 74 = O The concentrated mix was completely homogeneous, as result ed from the absence of crumbs and deposits on the mixer walls. Enlarged photographs of the mix revealed a uniform distribution of the stabilizers on the surfaces of the polymer granules, unlike what happens with a polymer mix not containing ethylene glycol-monolaurate. EXAMPLE 18 Into a Henschell-type mixer having a 10-liter capacityr the following was introduced - polypropylene in flakes - 1.780 kg - glycerine monostearate 0.020 kg - Ni-2,2'-thiobis(4-tert.octyl)-phenol ate-n.butylamine 0.200 kg Mixing was carried out at 250C for 5 minutes. The polypropylene in flakes employed exhibited a melt index= 12, a residue to the extraction with heptane = = 97.5f, an ash content = 75 ppm, an apparent density = = 0.51 and the following granulometric distribution. > 840 P = 4.4 420-840 P = 23.0 % 250-420 = 55.4 % 177-250 Y = 8.5 % 149-177 = 3.2 % 74-149 =. 5.5 % c 74 P = 0 The concentrated mix was completely homogeneous, as result ed from the absence of crumbs and deposits on the mixer walls. Enlarged photographs of the mix revealed a uniform distribution of the stabilizers on the surfaces of the polymer granules, unlike what happens with a polymer mix not containing glycerine monostearate. EXAMPLE 19 Into a 10-liter mixer, Henschell-type, the following was introduced - polypropylene in flakes 1.780 kg - glycerine monostearate 0.020 kg - azodicarbonamide 0.200 kg Mixing was carried out at 250C for 5 minutes. The polypropylene in flakes employed exhibited a melt index = 12, a residue to the extraction with heptane = = 97.5%, an ash content = 75 ppm, an apparent density = = 0.51 and the following granulometric distribution > 840 u = 4.4 % 420-840 = 23.0 % 250-420 P = 55.4 % 177-250 P = 8.5 % 149-177 P = 3.2 % 74-149 = 5.5 % 4 74 )1 O Q The concentrated mix was completely homogeneous, as result ed from the absence of crumbs and deposits on the mixer walls. Enlarged photographs of the mix revealed a uniform distribution of the blowing agent on the surfaces of the polymer granules, unlike what happens with a polymer mix ¯ not containing glycerine monostearate. 0.300 kg of concentrated mix was'diluted, by mixing in a 10-liter slow mixer, Battagion-type, with 2.700 kg of polypropylene flakes, to obtain a blowing agent concentration of 1%. To check the influence of the coupling agent on the homogeneous distribution of the blowing agent and on its thermal degradat6n,small plates were prepared with the dilute mix. The 2-mm thick plates were prepared in a Carver press by heating for 5 minutes to a temperature of 2400C. Dimensions and distribution of the pores formed during the thermal decomposition of the blowing agent, detected by photographic enlargements, showed a homogeneous distribution of the blowing agent in the polymer containing polyoxyethylene-dodecylamine, unlike what occurs in the sample not containing coupling agent. EXAMPLE 20 Into a 10-liter mixer, Henschell type, the following was introduced - polypropylene in flakes 1.780 kg - glycerine monostearate 0.020 kg - "Graftolo" Yellow RCL (C.I. Pigment Yellow 83) 0.200 kg Mixing was carried out at 250C for 5 minutes. The polypropylene in flakes employed exhibited a melt index = 12, a residue to the extraction with heptane = = 97.5g, an ash content = 75 ppm, an apparent density = = 0.51 and the following granulometric distribution > 840 P = 4.4 % 420-840 P = 23.0 % 250-420 P = 55.4 % 177-250 P = 8.5 % 149-177 = 3.2 % 74-149 = 5.5 % < 74 JI O 0 The concentrated mix was completely homogeneous, as result ed from the absence of crumbs and deposits on the mixer walls. Enlarged photographs of the mix revealed a uniform distribution of the pigment on the surfaces of the polymer gra nules, unlike what happens with a polymer mix not containing glycerine monostearate, in which the dyeing yield is much lower. 0.030 kg of concentrated mix were diluted by mixing in a 10-liter slow mixer, Battagion type, with 2.970kg of polypropylene flakes to obtain a pigment concentration of 0.1%. To check the influence of the coupling agent on the homogeneous distribution of the pigment and on the intensity thereof, besides to check its influence on the colour stability to thermal degration, small plates were prepared with the dilute mix. The l-mm thick plates were prepared in a Carver press by heating for 15 minutes to temperature of 2000C, 2400C, 26O0C, 2800C. In all the samples the pigment resulted thoroughly stable to thermal decomposition. The dilute mixture was directly fed to a melt spinning device Spinning and successive stretching were effected under the operating conditions reported hereinbelow - temperature of the head 2300 C - temperature of the spinneret 2300 C - temperature of the screw 2400 C -'spinneret type (number of holes/dia meter/height) 40/0.8/4 - max.pressure 32 kg/cmê - winding speed 400 m/min. - stretching temperature 1300 C - stretching medium vapour - stretching ratio 1:3.2 The fibres obtained exhibited a uniform pigmentation and the'fol1owing characteristics - count 17 dtex - tenacity 2.9 g/dtex - elongation 71 % EXAMPLE 21 Into a 10-liter mixer, Henschell-type, the following was introduced - polypropylene in flakes 1.340 kg - ethylene glycol monolaurate 0.060 kg - "Graftolo" oxide Red EOR 0.600 kg Mixing was carried out at 250C for 5 minutes. The polypropylene in- flakes employed exhibited a melt index = 12, a residue to the extraction with heptane = 97.5%, an ash content = 75 ppm, an apparent density = = 0.51 and the following granulometric distribution > 840 P = 4.4 % 420-840 r = 23.0 % 250-420 P = 55.4 % 177-250 = 8.5 % 149-177 )u = 3.2 % 74-143 P = 5.5 % < 74 = 0 % The concentrated mix was completely homogeneous, as resulted from the absence of crumbs and deposits in the mixer walls. Enlarged photographs of the mix revealed a uniform distribution of the pigment on the surface of the polymer granules, unlike what happens with a polymer mix not contain ing ethylene glycol monolaurate, in which the dyeing yield was much lower. EXAMPLE 22 A 10-liter mixer, Henschell type, was charged with - polypropylene in flakes 1.780 kg - n-dodecyl alcohol - 0.020 kg - "Graftolo" Yellow RCL (C.I. Pigment Yellow 83) 0.200 kg Mixing was carried out at 250C for 5 minutes. The polypropylene in flakes employed exhibited a melt index = 12, a residue to the extraction with heptane = = 97.5%, an ash content = 75 ppm, an apparent density = = 0.51 and the following granulometric distribution > 840 P = 4.4 % 420-840 P = 23.0 % 250-420 P = 55.4 % 177-250 P = 8.5 % 149-177 = 3.2 74-149 = 5.5 % < 74 = 0 % The concentrated mix was completely homogeneous, as resulted from the absence of crumbs and deposits on the mixer walls and from the uniform pigment coating on the polypropylene flakes. 0,030 kg of concentrated mix were diluted by mixing in a 10-liter quick mix, Henschell-type, with 2.970 kg of polypropylene flakes, to obtain a pigment concentration of O.iC; To check the influence of the coupling agent on the homogeneous distribution of the pigment and on its intensify besides to check the influence on the colour stability to thermal degradation, small plates with the dilute mix were prepared. The 1 mm plates were prepared in a Carver press by heating for 15 minutes to temperature of 2000C, 2400C, 260 C, 2800C, and did not show any alterations. EXAMPLE 23 A 10-liter mix, Henschell-type, was charged with - polypropylene in flakes 1.340 kg - n.dodecyl alcohol 0.060 kg - "Graftolo" oxide Red EOR 0.600 kg Mixing was carried out at 250C for 5 minutes. The polypropylene in flakes employed exhibited a melt index = 12, a residue to the extraction with heptane = = 97.5%, an ash content = 75 ppm, an apparent density = = 0.51 and the following granulometric distribution > 840 P = 4.4 % 420-840 P = 23.0 % 250-420 = 55.4 0 177-250 u = 8.5 % 149-177 - = 3.2 % 74-149 P = 5.5 % ( 74 = 0 The concentrated mix was completely homogeneous, as resulted from the absence of crumbs and deposits on the mixer walls and from uniform pigment coating on the polypropylene flakes. 0.010 kg of concentrated mix were diluted by mixing in a 10-liter quick mixer, Henschell-type, with 2.990 kg of polypropylene flakes to obtain a pigment concentration of To check the influence of the coupling agent on the homogeneous distribution of the pigment and on the intensity thereof, besides to check its influence on the colour stability to thermal degradatin,small plates were prepared with the dilute mix. The 1-mm thick plates were prepared in a Carver press by heating for 15 minutes to temperature of 200"C, 2400C, 2600C, 2800C, and did not exhibit any alternations. EXAMPLE 24 A 10-liter mixer, Henschell-type, was charged with : - propylene in flakes 1.780 kg - lauric acid 0.020 kg - "Graftolo" Yellow RCL (C.I. Pigment Yellow 83) 0.200 kg Mixing was carried out at 250C for 5 minutes. The polypropylene in flakes employed exhibited a melt index = 12, a residue to the extraction with heptane = = 97.5%, an ash content = 75 ppm, an apparent density = = 0.51 and the following granulometric distribution - > 840 =-4.4 % 420-840 r =23.0 % 250-420 =55.4 % 177-250 = 8.5 % 149-177 P = -3.2 % 74-149 f = 5.5 % 4 74 p1 O 0 The concentrated mix was completely homogeneous, as result ed from the absence of crumbs and deposits on the mixer walls and from the uniform pigment coating on the polypropylene flakes. 0.030 kg of concentrated mix was diluted by mixing in a 10 -liter quick mixer, Henschell-type, with 2.970 kg of polypropylene flakes to obtain a pigment concentration of 0.1%. To check the influence of the coupling agent on the homogeneous distribution of the pigment and on the intensity thereof, besides to check its influence on the colour stability to thermal degradation, small plates were prepared with the dilute mix. The 1-mm thick plates were prepared in a Carver press by heating for 15 minutes to temperature of 2000C, 2400C, 2600C, 2800C and did not exhibit any alternations. EXAMPLE 25 Into a 10-liter mixer, Henschell-type, the following was introduced - polypropylene in flakes 1.340 kg - sodium oleate 0.060 kg - "Graftolo" oxide Red EOR 0.600 kg Mixing was carried out at 250C for 5 minutes. The polypropylene in flakes employed exhibited a melt index = 12, a residue to the extraction with heptane = = 97.5f, an ash content = 75 ppm, an apparent density = = 0.51 and. the following granulometric distribution > 840 P = 4.4 % 420-840 P = 23.0 % 250-420 lu = 55.4 % 177-250 p = 8.5 % 149-177 u = 3.2 % 74-149 r = 5.5 % ( 74 P = O The concentrated mix was completely homogeneous, as result ed from the absence of crumbs and deposits on the mixer walls and from the uniform pigment coating on the polypropylene flakes. 0.010 kg of concentrated mix were diluted by mixing in a 10-liter quick mixer, Henschell-type, with 2.990 kg of polypropylene flakes to obtain a pigment concentration of 0.1%. To check the influence of the coupling agent on the homogeneous distribution of the pigment and on the intensity thereof, besides to check its influence on the colour stability to thermal degradation,small plates were prepared with the dilute mix. The 1-mm thick plates were prepared infra Carver press by heating for 15 minutes to temperature of 2000C, 2400C, 2600C, 2800C, and did not exhibit any alterations. The dilute mixture was directly fed to a melt spinning device. Spinning and succesive stretching were effected under the operating conditions reported hereinbelow - temperature of the head 2400 C - temperature of the spinneret 2400 C - temperature of the screw 2400 C - spinneret type (number of holes/dia meter/Height) 40/0.8/4 2 - max. pressure 32.7 kg/cm - winding speed 400 m/min. - stretching temperature 1300C - tretching medium vapour - stretching ratio 1:3.4 The fibres obtained exhibited a uniform pigmentation and the following characteristics - count 17 dtex - tenacity 2.9 g/dtex - elongation 85 % EXAMPLE 26 Into a 10-liter mixer, Henschell-type, the following was introduced - polypropylene in flakes 1.780 kg - n.octadecylamine 0.020 kg - "Graftolo" Yellow RCL (C.I. Pigment Yellow 83) 0.200 kg. Mixing was carried out at 25 C for 5 minutes. The polypropylene in flakes employed exhibited a melt index = 12, a residue to the extraction with heptane = = 97.5%, an ash content = 75 ppm, an apparent density = = 0.51 and the following granulometric distribution > 840 P = 4.4 % 420-840 P = 23.0 % 250-420 P = 55.4 % 177-250 P = 8.5 % 149-177 P = 3.2 % 74-149 = 5.5 % < '74 = O The concentrated mix was completely homogeneous, as result ed from the absence of crumbs and deposits on the mixer walls and from the uniform pigment coating on the polypro pylene flakes. 0.030 kg of concentrated mix were diluted by mixing in a lO-liter quick mixer, Henschell-type, with 2.970 kg of polypropylene flakes to obtain a pigment concentration of O . 1% . To check the influence of the coupling agent on the homoge neous distribution of the pigment and on the intensity thereof, besides to check its influence on the colour stability to thermal degradation, small plates were prepared with the dilute mix. The l-mm thick plates were prepared in a Carver press by heating for 15 minutes to temperature of 2000C, 2400C, 2600C, 2800C, and did not exhibit any alterations. EXAMPLE 27 A lO-liter mixer, Henschell-type, was charged with : - polypropylene in flakes 1.340 kg - n.octadecylamine 0.060 kg - "Graftolo" oxide Red EOR 0.600 kg Mixing was carried out at 250C for 5 minutes, The polypropylene in flakes employed exhibited a melt index = 12, a residue to the extraction with heptane = = 97.5%, an ash content = 75 ppm, an apparent density = = 0.51 and the following granulometric distribution > 840 = 4.4 % 420-840 = 23.0 % 250-420 P = 55.4 % 177-250 = 8.59 149-177 P = 3.2 % 74-149 = 5.5 % ( 74 X = O % The concentrated mix was completely homogeneous, as resul ed from the absence of crumbs and deposits on the mixer walls and from the uniform pigment coating on the polypropylene flakes. 0.010 kg of concentrated mix were diluted by mixing in a 10-liter quick mixer, Henschell-type, with 2.990 kg of po lypropylene flakes to obtain a pigment concentration of 0.1%. To- check the influence of the coupling agent on the homogeneous distribution of the pigment and on the intensity thereof, besides to check its influence on the colour stability to thermal degradation, small plates were prepared with the dilute mix. The 1-mm thick plates were pre pared in a Carver press by heating for 15 minutes to temperature of 2000C, 2400C, 2600C, 2800C, and did not exhibited any alterations. EXAMPLE 28 Into a 10-liter mixer, Henschell-type, the following was introduced - polypropylene in flakes 1.780 kg - polyoxyethylene alcohol C H 0- 12 25 -(CH2-CH2O) 28H 0.020 kg - "Graftolo" Yellow RCL (C.I. Pigment Yellow 83) 0.200 kg Mixing was carried out at 150C for 5 minutes. The polypropylene in flakes employed a melt index = 12, a residue to the extraction with heptane = 97.5, an ash content = 75 ppm, an apparent density = 0.51 and the following granulometric distribution > 840 P = 4.4 % 420-840 = 23.0 % 250-420 = 55.4 % 177-250 P = 8.5 % 149-177 = 3.2 % 74-149 P = 5.5 % ( 74 JI O 0 The concentrated mix was completely homogeneous, as resulted from the absence of crumbs and deposits on the mixer walls and from the uniform pigment coating on the polypropylene flakes. 0.030 kg of concentrated mix were diluted by mixing in a 10-liter quick mixer, Henschell-type, with 2.970 kg of polypropylene flakes to obtain a pigment concentration of 0.1%. To check the influence of the coupling agent on the homogeneous distribution of the pigment and on the intensity thereof, besides to check its influence on the colour stability to thermal degradation, small plates were prepa- red with the dilute mix. The 1-mm thick were prepared in a Carver press by heating for 15 minutes to temperature of 2000C, 2400-C, 260 C, 2800C, and did not exhibit any alterations. EXAMPLE 29 A 10-liter mixer, Henschell-type, was charged with - polypropylene in flakes . 1.340 kg - polyoxyethylene alcohol C12H250- -(CH2-CH2O) 18H 0.600 kg - "Graftolo" oxide Red EOR 0.600 kg Mixing was carried out at 250C for 5 minutes. The polypropylene in flakes employed exhibited a melt index = 12, a residue to the extraction w'ith heptane = = 97.5%, an ash content = 75 ppm, an apparent density = = 0.51 and the following granulometric distribution > 840 P = 4.4 % 420-840 P = 23.0 % 250-420 y = 55.4 % 177-250 = 8.5 % 149-177 = 3.2 % 74-149 P = 5.5 % < '74 = O The concentrated mix was completely homogeneous, as reuslt ed from the absence of crumbs and deposits on the mixer walls and from the uniform pigment coating on the polypropylene flakes. 0.010 kg of concentrated mix were diluted by mixing in a 10-liter quick mixer, Henschell-type, with 2.990 kgo-fpo lypropylene flakes to obtain a pigment concentration of 0.1%. To check the influence of the coupling agent on the homogeneous distribution of the pigment and on the intensity thereof, besides to check its influence on the colour stability to thermal degradation, small plates were prepared with the dilute mix. The 1-mm thick plates were prepared in a Carver press by heating for 15 minutes to tem- perature of 2000C, 2400C, 2600C, 2800C, and did not exhibit any alterations.

Claims: WHAT WE CLAIM IS 1) A process for preparing homogeneous compositions of olefinic polymers in flakes and of additives, suit able for direct transformation into manufactured articles, consisting in mixing the polymer with the additive and with a third component, acting as a coupling agent, selected from the class consisting of liquid or solid paraffinic compounds having a linear or branched chain, containing from 2 to 500 carbon atoms, which is employed in the pure state or in solution in hydrocarbon solvents, at the rate of 0.01-5% by weight referred to the total of the ; mix. 2) A process according to claim 1, in which the coupl ing agent employed is a paraffinic compound contain ing one or more polar functional groups. 3) A process according to claim 2, in which use is ma de of a coupling agent comprised in the general for mula R-X wherein R is a linear or branched alkyl radical hav ing 12 to 30 carbon atoms, X may be a) -OH b) -COOH or corresponding salts of alkaline metal c) -NR'R" in which R' and R", either like or un like each other; are hydrogen or alkyls having 1 to 12 carbon atoms d) -O(CH2CH2O)n-H, -O[CH(CH3)CH2O]n-H in which n = 1-50, preferably 5-20. EMI41.1 in which n and n', either like or unlike each other, are comprised between 0 and 50, at least one being different from 0 f) OCOR"' in which R"' is an alkyl containing hydro xyl groups, in particular it can be a radical deriv ing from polyols, such as ethylene glycol, glyceri ne, pentaerythritol. 4) A process according to claim 1, in which a substance selected from amongst : vaseline oil, paraffin waxes, oligomers of ethylene or of propylene, low molecular weight polypropylene, is employed as coupling agent. 5) A process according to claim 3, in which use is made of a coupling agent comprised in general formula R-X, in which R is a linear or ramified alkyl having 12 to 18 carbon atoms. 6) A process according to claim 1, in which use is made of flakes of crystalline olefinic polymers prepared by means of stereospecific catalysts, in particular of flakes of polypropylene having prevailingly isotactic macromolecules or of ethylene-propylene crystalline copolymers containing prevailingly propylene, either of the random type and in blocks. 7) A process according to claim 1, in which stabilizers, opacifiers, organic and inorganic pigments, blowing agents, lubricants, antistatic agents, dyeing modi fiers, hydrophilizing agents and the like are employ ed as additives. 8) Additioned polyolefinic compositions, consisting of polyolefinic flakes, additives and a third coupling agent, selected from the class of the paraffinic compounds indicated in any of claims 1 to 5.

Inventors: CAMPRINCOLI, PIERPAOLO, DR., CAPPONI, PIETRO, SPAGNOLI, LEONARDO
Applicants: MONTEDISON S.P.A.
Application year: 1979
Main classification: C08J3
IPC codes: C08L23, C08J3, C08L7, C08J9, C08L101, C08L21