MXPA97002945A - Process for the preparation of elastomeric compounds, from polymers and granular elastomers, as well as articles manufactured with the - Google Patents

Abstract

The present invention provides a continuous process for forming compounds from one or more polymers and the finished articles made therefrom. The process comprises the continuous feeding of at least one granular elastomer, optionally, with one or more thermoplastic polymers, having average particle sizes of about 5mm or less and, optionally, with one or more additives, to a continuous mixer, where the components are chewed and fused into a compound and by pumping said compound through a hole or matr

Description

PROCESS FOR THE PREPARATION OF ELASTOMERIC COMPOUNDS. FROM POLYMERS AND ELASTOMERS GRANULARS AS WELL AS ARTICLES MANUFACTURED WITH THEM Field of the Invention This invention relates to a continuous process for preparing compounds comprising a granular elastomer and, optionally, other thermoplastic elastomers and polymers. The invention also relates to articles produced from the compounds prepared by this process. Background of the Invention Elastomers, particularly those in the form of bales, require a step-by-step manufacturing process in the finished articles. The discontinuity in the process is due to the need to break the bale or pellets into smaller domains to effect a good internal dispersion of the elastomer with various ingredients used in the formulation of the compound. Current methods of incorporating elastomers into fully formulated products typically use batch mixers, such as the tangential mixer (Banbury) or the internal gear mixer, with a one or two stage mixing step. In the single stage, all the mixing ingredients, such as rubber, carbon black, white filings, plasticizers and other additives, solid or liquid, are added into the mixer, including curing agents, provided that the temperatures of discharge are below 115OC. With the passage of the two-stage mixer, in the first stage, several ingredients are added, such as the filling of carbon black, plasticizers and other additives, solid or liquid, inside the mixer, to supply the mixture of the dough homogeneous melting and dispersion of the ingredients. This mixture is achieved at high temperatures of the metals of about 140 to 1602C or higher, for the compositions, which include the thermoplastic polymers. The mixed batch is then discharged onto a two roll mill, or in an extruder, and sheets, sheets or pellets are formed therefrom. In the second stage, the compound is fed to a second mixer. For vulcanizable compositions, curing agents are added at that stage, while maintaining the temperature of the material below 1153C, in order to prevent its activation, which would lead to premature entanglement of the elastomeric composition. Higher process temperatures are necessary for compositions that include a thermoplastic polymer or where dynamic vulcanization is desirable. The compound can be discharged into the process equipment to configure it in an intermediate form for later use or in the final form of the finished article.

Also, the continuous composition equipment typical of the thermoplastic processes known in the art, such as the twin screw extruders (erner &Pfleiderer, Berstorff, etc.) and continuous mixers (Farrel, Kobe Steel, Japan Steel, et.) they can be used sometimes, instead of mixers in batches. However, these devices require the use of continuous feeding of free-flowing ingredients, and conventional forms of rubber bales are not suitable for this application. Similarly, the use of conventional continuous mixers and extruders is prohibitive with the milled forms of conventional rubbers, due to their limited availability in the selection of the desired properties and the expense in grinding and maintaining the elastomer in a free-flowing state. All these traditional methods of composition suffer from the complexity of the mixing process and the related operations, such as the handling, mixing and storage of the raw material and the semi-finished and intermediate formulated products. These methods are labor intensive and energy intensive and require substantial investments in the process equipment, thus adding a substantial cost to the finished product. In view of the current state of the art for the manufacture of articles, where at least one elastomer is composed in a final composition, a method which reduces labor and energy costs, compared to conventional methods, and that can be applied to a full range of commercial products, would be clearly selling - 5 josé. SUMMARY OF THE INVENTION The present invention provides a continuous process for composing one or more polymers, which comprises: (i) feeding at least one granular elastomer, optionally, with one or more thermoplastic polymers and, optionally, with one or more additives, to a continuous mixer; (ii) chewing the granular elastomer with the optional thermoplastic polymers and the optional additives, when present, in the continuous mixer, to form a compound; (iii) pump the compound through a die or die, downstream to the end of the continuous mixer. In addition, a process for the continuous composition of one or more polymers is provided, which comprises: (i) mixing at least one granular elastomer, optionally, with one or more thermoplastic polymers and, optionally, with one or more additives, when present, in a mixing vessel to form a mixture; (ii) continuously feeding the mixture with the thermoplastic polymers and optional additives, when present, to a continuous mixer; (iii) chewing the mixture to form a compound; (iv) pumping the compound through a die, downstream to the end of the continuous mixer. The articles, prepared according to the processes, use free-flowing granular polymers and resins produced in a gas-phase polymerization, which have improved and different end-use advantages and capacities. Brief Description of the Drawing Figure 1 is a schematic view of the continuous stage of rubber composition. In this figure, the components and steps of the invention are shown. The solid ingredients are fed through (a) feeders of gravimetric or volumetric design, the liquid ingredients are added with dosing pumps (b). The mixture is fed to a pre-mixer, which may be of a continuous type, such as the Littleford® (c), plow-style, or batch-type mixer, such as the Henschel® mixer, in which case, it can be used an additional feeder after the Henschel® mixer to dose the mixture in a continuous mixer. Oil is sprayed and atomized through the nozzle (d). After mixing with a residence time of 1 to 5 minutes, the mixture is fed to a continuous mixer (e). Additional oil, such as, for example, in (f), is injected into the continuous mixer, if desired. The temperature control element (g) is used, if required, for the cylinders (i) and the rotors (j). The mixture is chewed and melted and the volatile products are discharged through a ventilation door. The mixed polymer is extruded through a profile die (1) in a configuration or in pellets. The profile is heated or irradiated by means of a heating element () to achieve vulcanization. Alternatively, the curing additives can be injected directly into the continuous mixer (e). Detailed Description of the Invention Recent patents, such as patents of E. U. A., NOS. 4,994,534, 5,304,588, 5,317,036 and 5,453,471 teach the production of elastomeric polymers in the gas phase in a fluidized bed reactor. The gas phase polymerizations can be conducted in a conventional condensed process form, including the induced condensate mode (US Patent Nos. 4,543,399, 4,588,790, 5,352,749 and 5,462,999) and the liquid monomer mode (US Pat. U.S.A. Patent No. 5,453,471); PCT 95/09826 and PCT 95/09827). The elastomers produced by these processes are free-flowing and granular, with an average diameter size of up to about 5 mm, preferably up to about 2 mm or less and more preferably of about 1 mm or less. In general, these elastomeric polymers are polymerized at or above the stickiness or softening temperature of the polymer that is produced using one or more inert particulate materials. These inert particulate materials, sometimes referred to as fluidization aids, are described in U.S. Patent No. 4,994,534 and include carbon black, silica, clay, talcum, and its mixtures. Of these, carbon black, silica or a mixture thereof are preferred. Carbon black is the most preferred inert particulate material. The free flowing, granular polymers produced in the gas phase, at a temperature above the softening point of the polymer product, in the presence of an inert particulate material, are unique and different from the powdered, particulate, shredded rubbers or in pellets, produced by commercial polymerizations in solution / volume, the polymer product in gas phase has a core / shell morphology with the inert particulate material incorporated in the polymer, with most of this particulate material concentrated in the shell , to provide a granular form of free flow over a wide range of comonomer and molecular weight compositions. In contrast, even if a filler is added to conventional shredded materials, described above, it will only supply physical and powdery mixtures. Also, in distinctive contrast to the non-gas phase rubbers, such as, for example, the use of crushed tires, the granular rubbers produced in the gas phase of the present invention (eg granular products of EPDM, EPM and BR). they are completely capable of being the primary component of rubber in typical rubber compounds and are also capable of vulcanization of sulfur or peroxide. Illustrative of the free-flowing granular elastomers, obtained in a gas phase process, which can be processed, according to the invention, are the following: IR (polyisoprene) BR (polybutadiene) SBR (butadiene polymer copolymerized with styrene ); Nitrile (butadiene polymer copolymerized with acrylonitrile) Butyl (isobutylene polymer copolymerized with isoprene) EPM (ethylene polymer copolymerized with propylene) EPDM (ethylene polymer copolymerized with propylene and a diene, such as hexadiene, dicyclopentadiene or ethylidene norbornene ) Copolymer of ethylene and an alpha-olefin having 3 to 12 carbon atoms Ethylene terpolymer, an alpha-olefin having from 3 to 12 carbon atoms, and a diene (preferably unconjugated) Neoprene® (polychloroprene) Silicone ( polydimethylsiloxane) Ethylene-vinyltrimethoxysilane copolymer Copolymers of ethylene and one or more of acrylonitrile, maleic acid esters, vinyl acetate, esters of acrylic and methacrylic acids, and the like Copolymers of butadiene and isoprene Polystyrene Styrene terpolymers, butadiene and isoprene Chlorobutyl (chlorinated copolymer of isobutylene and isoprene) Bromobutyl (copolymer brominated isobutylene and isoprene) Brominated copolymer of isobutylene and para-methylstyrene. Chlorinated and chlorosulfonated polyethylenes Of these, polyisoprene, polybutadiene, poly (styrene-butadiene) rubber, ethylene-propylene rubber (EPM) and ethylene-propylene and diene rubber (EPDM) are preferred. The tetrapolymers, according to WO 96/11960 and WO 96/12744 can also be continuously compounded in the manner described herein. One method of practicing the invention comprises continuously feeding to a continuous mixer at least one granular elastomer together with various thermoplastics and additive materials, which comprises the formulation of the final composition. The mixer is °? process equipment in which the elastomer and additives are chewed and dispersed to form a compound. Although any process equipment is capable of chewing such a composition, continuous mixers are preferred, such as Farrell's FCM® and the like, or dual-screw composing apparatus or extruders, such as the ZSK® series from Werner and Pfleiderer and similar, planetary or Berstorff® mixers or single screw extruders or without bolts in the cylinder, as supplied by Davis Standard® or rotating screws that move axially reciprocally, such as the Buss-Condux® type. The extruders, generally and preferably, have a cylinder containing a single rotor, a double rotor or a combination of single and double rotors. Typically, the cylinder has one or more feed doors and, optionally, one or more ventilation doors positioned along its length. The various elastomers, thermoplastic polymers and additives can be introduced alone or together through the ventilation doors. While one or more rotors may be employed, preferably no more than two are used. The chewed compound is then pumped through a hole or matrix. Generally, the hole is a matrix used to form the composite in an intermediate configuration for later use or in the form of a finished article. Continuous mixers are usually designed to pump the compound directly through the matrix. Alternatively, it can be achieved externally to the continuous mixer by continuously feeding the chewed compound to a single screw extruder, a twin or twin screw extruder or a melt pump. It will be understood that the feed of the granular elastomer and the optional additives and / or other thermoplastic materials of the composition can be performed simultaneously in more than one location along the mixer, the pumping extruder and the melt pump, introducing such materials at one or more sites in the mixer or along the extruder by means of openings, holes or ventilation doors. In another embodiment of the invention, at least one granular elastomer is continuously fed to the mixer with one or more granular thermoplastic polymers and with part of the additives of the composition. The particle size of these polymers is about 5 mm or less, preferably 2 mm or less and more preferably 1 mm or less.

In general, thermoplastic polymers are characterized by their ability to retain useful end-use properties, without the use of interlacing the molecular network by some external agents, such as in the case of elastomers. Examples of thermoplastic polymers are polyethylenes and their related copolymers, such as the copolymers of butene, propylene, hexene, osteno, 4-methyl-1-pentene; functional grades of polyethylenes, such as esters of maleic acid, esters of acrylic and methacrylic acids, acrylonitrile, vinyl acetate and its derivatives, such as polyethylenes and chlorinated and sulphonated copolymers; polypropylene and its related copolymers; functional grades of polypropylenes, such as esters of maleic acid and esters of methacrylic acid; modified grades of polypropylene and copolymers; ionomers, polyvinyl chlorides and their related copolymers, and functional and modified grades; acetal polymers and their related copolymers and modified grades; fluorinated olefin polymers; polyvinylidene fluoride; polyvinyl fluoride; polyamides and their modified grades; polyimides; polyacrylates; polycarbonates and their related copolymers and modified grades; polyethers; polyether sulfones; polyarylsulphones; polyketones; polyetherimides; poly (4-methyl-1-pentene); polyphenylenes and modified grades; polysulfones; polyurethanes and their related modifi ed grades; polyesters and their related modified grades; polystyrene and its related sopolymers and modified grades; polybutylene; acrylonitrile polymers, polyacrylates, their mixtures, and the like. Of these, polyethylene and its related copolymers, such as copolymers of butene, propylene, hexene, octene, 4-methyl-1-pentene, functional grades of polyethylene, such as esters of maleic acid, esters of acrylic acid and methacrylic, vinyl acetate and derivatives, such as polyethylene and chlorinated and sulfonated copolymers; polypropylene and its related copolymers, functional grades of polypropylene, such as esters of maleic acid, esters of acrylic and methacrylic acids, modified grades of polypropylene and copolymers; poly (vinyl chloride) and its related copolymers, functional and modified grades; polyamides and their modified grades; polyesters and their related modified grades; polystyrene and its related copolymers and modified grades; polyurethanes and their related modified grades; polyesters and their related modified grades are preferred. It will be further understood that the elastomers, which are mixed according to the process of this invention, do not have to be chemically distinct, provided they are substantially different in some aspect of the molecular structure, for example, they can be the same elastomers in two substantially different degrees of molecular weights or contain substantially different amounts or ratios of the respective monomers comprising them. The same is true for thermoplastic polymers, when they are used. Another embodiment of the invention consists in mixing at least one granular elastomer with, optionally, one or more polymers. Optionally, the mixture contains, in addition to the polymers, any or all of the other ingredients or additives of the composition. Any of the conventional methods for physically mixing the particulate solids, such as, for example, stirring or stirring, can be used to prepare the mixture. The mixing vessel is operated in intermittent or continuous mode. The mixture is then continuously fed to the mixer, where it is continuously chewed in a compound. It will be understood that the mixture comprises at least two constituents of the composition. The additives and polymers not included in the mixture are fed continuously to the mixer in the same place where the mixture is fed or in other suitable places, by means of openings or orifices along the mixer, the pump screw or the molten pump. The ingredients or additives mentioned in the invention are optionally selected from the group consisting of fillers, plasticizers, anti-oxidants and anti-ozone agents, activators, accelerators, tackifiers, homogenizing agents, peptizers, pigments, flame retardants, auxiliary agents. process, such as sulfur, vulcanized vegetable oil (Factice) and fungici-das. Fillers, for use as an additive of the invention, include carbon black; silicates of aluminum, magnesium, calcium, sodium, potassium and their mixtures; carbonates of calcium, magnesium and their mixtures; silicon, calcium, zinc, iron, titanium and aluminum oxides, calcium, barium and lead sulfates; alumina trihydrate; magnesium hydroxide; phenol-formaldehyde resins, polystyrene and poly (alpha-ethyl) styrene, natural fibers, synthetic fibers and the like. Plasticizers for use in the invention include petroleum oils, such as aromatic, naphthenic and paraffinic oils according to ASTM D2226; polyalkylbenzene oils; monoesters of organic acids, such as the alkyl and alkoxyalkyl oleates and stearates; diesters of organic acids, such as phthalates, terephthalates, sebacates, adipates and dialkyl glutarate, dialkoxyalkyl and alkyl aryl; glycol diesters, such as the dialkanoates of tri-, tetra- and polyethylene glycols; triallyl trimellitrates; trialkyl, tri-alkoxyalkyl, alkyl-diaryl and triaryl phosphates; chlorinated paraffin oils; cumarona-indene resins; pine tars, vegetable oils, such as castor oils and esters, a by-product of wood pulp, turnip and soybean, and esters and their epoxidized derivatives; and similar. Antioxidants and additives against ozone, for use in the invention, include hindered phenols, bisphenols and thiobisphenols; substituted hydroquinones; tris (alkylphenyl) phosphites; dialkylthiodipropionates; phenyl-naphthylamines; substituted diphenylamines; p-phenylene diamines substituted with dialakyl, alkyl, aryl and diaryl; monomeric and polymeric dihydroquinolines; 2- (4-hydroxy-3,5-t-butylaniline) -4,6-bis (octithio) -l, 3,5-triazine, hexa-hydro-1,3,5-bis-β- (3, 5-di-t-butyl-4-hydroxyphenyl) propionyl-s-triazine, 2,4,6-tris (n-1,4-dimethylpentylphenylenediamino) -1,3,5-triazine, tris- (3,5- di-t-butyl-4-hydroxy-benzyl) isocyanurate, nickel dibutyldithiocarbamate, 2-mercaptotolylimidazole and its zinc salt, petroleum waxes, and the like. Other optional additives for use in the invention include activators (metal oxides, such as zinc, calcium, magnesium, cadmium and lead oxides; fatty acids, such as acids, stearic, lauric, oleic, behenic and platinum, and its salts of zinc, copper, cadmium and lead, di-, tri- and polyethylene glycols, and triethanolamine); accelerators (sulfenamides, such as benzothiazole sulfenamides, including bis-benzo-thiazole sulfenamides, and thiocarbamyl sulfenamides, thiazoles, dithiocarbamates, dithiophosphates, thiurams, guanidines, xanthanes, thioureas, and mixtures thereof); tackifiers (rosin and rosin acids, hydrocarbon resins, aromatic indene resins, phenolic methylene donating resins, thermosetting phenolic resins, resorcenol-formaldehyde resins, and alkyl phenol-formaldehyde resins, such as octyl resin -phenol-formaldehyde); homogenizing agents, peptizers, pigments, flame retardants, fungicides, and the like. The total amount of the optional ingredients may vary from about 40 to 800 parts by weight, based on 100 parts of the elastomers in the composition. Vulcanizing agents for use in the invention include sulfur-containing compounds, such as elemental sulfur, 4,4'-dithiodimorpholine, di- and polysulfides of thiuram, disulfides of alkylphenol and 2-morpholino-dithio-benzothiazole; peroxides, such as di- (tertiary butyl peroxide), tert.-butylcuoyl peroxide, dicumyl peroxide, 2,5-dimethyl-2,5-di (tere.-butylperoxy) hexane, di (tere. butylperoxyisoprpyl) benzene, tere peroxybenzoate. -butyl and 1,1-di- (tere-butylperoxy) -3,3,5-trimethyl-cyclohexane; metal oxides, such as zinc, magnesium and lead oxides; dinitroso compounds, such as p-quinone dioxime and p, p'-dibenzoylquinone dioxime; and phenol-formaldehyde resins containing hydroxy ethyl or halomethyl functional groups. It will be understood that mixtures of two or more vulcanizing agents can be used in the process of the invention. The proper form of any of these vulcanizing agents for use in the invention will be greatly governed by the selection of the elastomers, as is well known to those skilled in the art of compositions. For the preferred elastomers of the invention, the sulfur-containing compounds and the peroxides are the preferred vulcanizing agents and most preferred are the sulfur-containing compounds. The amount of the vulcanizing agent can vary from about 1 to 10 parts by weight, based on 100 parts of the elastomers in the co-position. The temperatures and vulcanization times employed are typical. Temperatures that vary approximately from 121 to 204 and times that vary from approximately 1 to 60 minutes are employed. The product of the final composite polymer, produced by the process of the invention or at least one of the ingredients (a granular elastomer, a thermoplastic polymer or an additive),. which comprise the composite product, are vulcanized dynamically in a continuous mixer.

The invention is particularly useful in the manufacture of vulcanizable EPDM articles, such as roof membranes, environmental seals and belts, hoses and tubes and molded articles. The invention offers great advantages in the preparation of thermoplastic elastomers, commonly referred to as TPE, where the dispersion of the rubber phase in the thermoplastic matrix is critical in the performance of the resulting composition. Examples of TPE are propylene and impact-modified copolymers, impact-modified polyesters, impact-modified polyamides and modified polyurethanes on impact. Similarly, the invention is applicable in the preparation of dynamically vulcanized thermoplastic elastomers characterized by a vulcanized rubber phase. Examples of dynamically vulcanized thermoplastics, named as TPV, are mixtures of EPDM and propylene, such as Santoprene®, EPDM and polyethylene, such as Sarlink®, or any other combination where the dispersed phase in a vulcanizable rubber and the phase continuous is a thermoplastic. The invention is also useful in the manufacture of tire sidewalls, comprising a mixture of EPDM and one or more highly unsaturated elastomers (eg, BR, SBR and IR) The advantage of granular elastomers, previously mixed, in the process of the invention, on conventional bale elastomers, is that these granular elastomers, previously mixed, enter the highly energy-intensive, highly interdispersed chewing process in a clear manner. Consequently, considerably less chewing is necessary to achieve high degrees of the desired internal dispersion for optimum performance than if the elastomers entered the chewing process in the conventional way in bales. Thus, the elastomers previously mixed, in gas phase, granular, can be mixed to a high degree of interdispersion of the elastomers in a short time and with less degradation of the polymer than the conventional elastomers in bales. Specially formulated elastomeric compounds prepared according to the process of this invention can be extruded through a die to produce articles such as strips materials for treads, sidewalls and flange filling components of a pneumatic rim, or used to produce sheets for the internal air retention liner. Other elastomeric, specially formulated compounds prepared in accordance with this invention can be calendered on steel cord fabrics or textiles to produce cords reinforced sheet material for frame components and the circumferential tire band. All patents mentioned herein are incorporated by reference.

The following examples are provided to illustrate the invention and are not intended to be limitations thereof. The amounts are in percent by weight, unless otherwise specified. EXAMPLES Example 1 This example illustrates the options of the appropriate process equipment to continuously compose an EPDM in granular form, with additives and fillers. The components of the compound formulation, shown in Table I, were placed in a 50 HP Henschel® FM 200 C mixer, with the exception of the oil. While mixing the ingredients, the oil was heated and sprayed into the mixer to obtain a premix. This resulting premix was fed continuously to the various composition equipment, described above. Although the premix was prepared in batches, the automatic further form of the feed process is possible and advantageous, as shown schematically in Figure 1, where solid ingredients, such as granular elastomers, optionally thermoplastic resins, fillers and additives they are continuously fed to a mixer, C by means of gravimetric feeders A. The liquid components that enter the formulation of the compound, as in this particular case the oil, were introduced into the mixer by means of the pumps B through the nozzle D. Optionally, a second nozzle F can be used to divide the charge of the liquid components directly into the composition apparatus . The continuous composition of the premix was demonstrated in a single screw extruder, an erner® and Pfleiderer® co-rotary inter-extruder extruder, and a non-intermixing counter-rotary mixer. The screw design of each machine is given in table 2. Among the variables of interest to exemplify the use of the invention are the final charge temperature and the quality of the dispersion. The final temperature of the compound needs to be such that it prevents the premature activation of the curing agents, while the dispersion of the ingredients is critical to achieve the physical properties in the cure. As indicated in Table 2, the conditions under which the composition equipment operates, which provide useful compounds for the manufacture of the finished articles, while the dispersion was better or equal to that found in similar compounds mixed in batches.

TABLE 1 Formulation of the composition TABLE 2 1 Extruder of a thyme: Loading section: External diameter 20.17 cm., Step 20.32 cm., UD 3.375, decrease of root diameter of 17.78 cm. at 8.89 cm., through the compression zone. Compression section: L D = 1 Dosing section: External diameter: 11.40 cm., step: 11.43, UD: 4.5, depth of the channel: 1.252 cm. 2 ZSK-5s 3-LOBE extruder, co-rotating, double thyme: Nominal screw diameter: 58 mm 3 Counter-rotating double-screw LCM-50 extruder: Nominal diameter of the thyme: 50 mm Example 2 Elastomers are often composed of rigid thermoplastics, in order to make them more durable. These blends are typically rich in thermoplastic, which have the elastomer as a discrete disperse phase. The compositions provided in Table 2 represent typical formulations of a class of materials denoted as thermoplastic olefins or TPO. This class of materials commonly employs polypropylene as the rigid thermoplastic and the ethylene-propylene rubber as the elastomer. The composition is carried out in a continuous mode of operation, preferably in a twin screw extruder or equivalent. Note that, due to the continuous nature of the equipment, the commercial elastomers used to produce the TPOs are either in the form of pellets or in master batches with the polypropylene. In this example, we chose the DFDB-1085 in the form of pellets as the control. This is a low density ethylene-butene copolymer, a thermoplastic resin that has characteristics similar to elastomers. This product is available from Union Carbide. Five granular elastomers, labeled A-D and I, were compared to a commercial impact modifier, DFDB-1085, in a typical TPO formulation. The composition of the granular elastomers is shown in Table 3. Each elastomer was compounded in a polypropylene homopolymer of 12 MFR in a 25 mm twin-screw extruder, Berstorff®. The process conditions are shown in Table 4. As shown in Table 4, the granular elastomers show an equivalent performance compared to the commercial control of the impact modifier.

TABLE 3 Composition of Granular Elastomers The screw configuration is as follows *: 9 X C / 3 X KB / B / 5 X P / LGM / 4 X P / 2 X SGM / C / 2 X S / C * Key of the screw design: C = transport section; KB = kneading block; B = blister ring; P = compression, LGM = large gear mixer; SGM = small gear mixer; S = spacer.

TABLE 4 EXPERIMENTAL DESIGN AND RESULTS TABLE 4 (Continued) Example 3 Mixtures of elastomer and thermoplastics, rich in elastomer, are often referred to as thermoplastic elastomers (TPE). A subset of the TPE family is a composition where the elastomer is interlaced in itself. These polymer blends are referred to as dynamic vulcanizates. They offer properties that are very similar to those of traditional entangled elastomers, but have the advantage of being reprocessable. The current manufacturing practice employs a master batch that approaches the delivery of the elastomer on a continuous basis. In this example, we compared the use of granular elastomers and masterbatch in the manufacture of a typical thermoplastic dynamic vulcanizate. Three granular elastomers, labeled A-C in Table 5, were compared with a master batch of polypropylene / ethylene-propylene rubber (33:67). The composition in each formulation is shown in Table 6. All ingredients in the composition, except the healing activator, were fed into the extruder inlet port. The healing activator was added through a second entry port, one third of the length of the cylinder, downstream of the initial entry door. Ventilation was placed near the outlet to remove volatile products. The mixtures were compounded in a 25 mm twin screw extruder, Berstorff®. Although less working hand and energy intensity was used in the preparation, the properties of the composite product with the granular elastomers showed an equivalent performance compared to the commercially available elastomers.

TABLE 5 Composition of Granular Elastomers TABLE 6 Experimental Design per = parts per 100 parts of resin.

Claims (9)

1. CLAIMS 1. A continuous process for the composition of one or more polymers, which comprises: (i) feeding at least one granular elastomer, optionally, with one or more thermoplastic polymers and, optionally, with one or more additives, to a mixer keep going; (ii) chewing the granular elastomer with the optional thermoplastic polymers and the additives, when present, in the continuous mixer, to form a compound; (iii) pumping the compound through a die, downstream of the continuous mixer.
2. 2. The process according to claim 1, wherein the granular elastomer is selected from the group consisting of: an ethylene-propylene copolymer; termorated ethylene-propylene and diene; ethylene copolymer and an alpha-olefin, having from 3 to 12 carbon atoms; ethylene terpolymer, an alpha-olefin, having from 3 to 12 carbon atoms, and a diene; polyisoprene; polybutadiene; a butadiene polymer copolymerized with styrene; an acrylonitrile, butadiene, and styrene polymer; a butadiene polymer copolymerized with acrylonitrile; an isobutylene polymer copolymerized with isoprene; polychloroprene; a polydi ethyl siloxane; copolymers of ethylene and vinyltrimethoxy-eilane; copolymers of ethylene and one or more of acrylonitrile, esters of maleic acid, vinyl acetate, esters of acrylic and methacrylic acids; copolymers of butadiene and isoprene; styrene, butadiene and isoprene terpolymers; chlorobutyl (chlorinated copolymer of isobutylene and isoprene) bromobutyl (brominated copolymer of isobutylene and isoprene) and brominated copolymer of isobutylene and para-methylstyrene and in which the thermoplastic polymers are selected from the group consisting of the polyethylenes and their related copolymers, such as the copolymers of butene, propylene, hexene, octene, 4-methyl-1-pentene; functional grades of polyethylenes, such as esters, of maleic acid, esters of acrylic and methacrylic acids, acrylonitrile, vinyl acetate and its derivatives, such as polyethylenes and chlorinated and sulphonated copolymers; polypropylenes and their related copolymers; functional grades of polypropylenes, such as esters of maleic acid and esters of methacrylic acid; modified grades of polypropylene and copolymers; ionomers; polyvinyl chlorides and their related copolymers, and functional and modified grades; acetal polymers and their related copolymers and modified grades; fluorinated olefin polymers; polyvinylidene fluoride; polyvinyl fluoride; polyamides and their modified grades; polyimides; polyacrylates; polycarbonates and their related copolymers and modified grades; polyethers; polyether sulfones; polyarylsulphones; polyketones; polyetherimides; poly (4-methyl-1-pentene); polyphenylenes and modified grades; polysulfones; polyurethanes and their related modified grades; polyesters and their related modified grades; polystyrene and its related copolymers and modified grades; polybutylene; Acrylonitrile polymers, polyacrylates, their mixtures.
3. 3. The process according to claim 2, wherein the granular elastomer is polymerized in the gas phase, optionally, in the presence of an inert particulate material, selected from the group consisting of carbon black, silica, clay, talc and its mixtures; in which the continuous mixer has one or more rotors enclosed in a cylinder, this cylinder has one or more feed ports and, optionally, one or more ventilation doors, located along its length, and at least one capillary or profile matrix connected to the cylinder; and this continuous mixer, optionally, is coupled to a melt pump or a single screw extruder.
4. 4. The process according to claim 1, wherein the dynamic vulcanization of the elastomeric phase is carried out in a continuous mixer.
5. 5. A continuous process for the composition of one or more polymers, which comprises: (i) mixing at least one granular elastomer, optionally, with one or more thermoplastic polymers and, optionally, with one or more additives, in a mixing vessel , to form a mixture; (ii) continuously feeding the mixture with the optional thermoplastic polymers and additives, when present, to a continuous mixer; (iii) chewing the mixture to form a compound; and (iv) pumping the compound through a die, downstream of the end of the continuous mixer.
6. 6. The process according to claim 5, wherein the granular elastomer is selected from the group consisting of: an ethylene-propylene copolymer; ethylene-propylene and diene thermonomer; ethylene copolymer and an alpha-olefin, having from 3 to 12 carbon atoms; ethylene terpolymer, an alpha-olefin, having from 3 to 12 carbon atoms, and a diene; polyisoprene; polybutadiene; a butadiene polymer copolymerized with styrene; an acrylonitrile, butadiene and styrene polymer; a butadiene polymer copolymerized with acrylonitrile; an isobutylene polymer copolymerized with isoprene; polychloroprene; a polydimethyl siloxane; copolymers of ethylene and vinyltrimethoxy-silane; copolymers of ethylene and one or more of acrylonitrile, esters of maleic acid, vinyl acetate, esters of acrylic and methacrylic acids; copolymers of butadiene and isoprene; styrene, butadiene and isoprene terpolymers; chlorobutyl (chlorinated copolymer of isobutylene and isoprene) bromobutyl (brominated copolymer of isobutylene and isoprene) and brominated copolymer of isobutylene and para-methylstyrene and in which the thermoplastic polymers are selected from the group consisting of polyethylenes and their related copolymers, such as the copolymers of butene, propylene, hexene, octene, 4-methyl-1-pentene; functional grades of polyethylenes, such as esters of maleic acid, esters of acrylic and methacrylic acids, acrylonitrile, vinyl acetate and its derivatives, such as polyethylenes and chlorinated and sulphonated copolymers; polypropylenes and their related copolymers; functional grades of polypropylenes, such as esters of maleic acid and esters of methacrylic acid; modified grades of polypropylene and copolymers; ionomers; polyvinyl chlorides and their related copolymers, and functional and modified grades; acetal polymers and their related copolymers and modified grades; fluorinated olefin polymers; polyvinylidene fluoride; polyvinyl fluoride; polyamides and their modified grades; polyimides; polyacrylates; polycarbonates and their related copolymers and modified grades; polyethers; polyether sulfones; polyarylsulphones; polyketones; polyetherimides; poly (4-methyl-1-pentene); polyphenylenes and modified grades; polysulfones; polyurethanes and their related modified grades; polyesters and their related modified grades; polystyrene and its related copolymers and modified grades; polybutylene; Acrylonitrile polymers, polyacrylates, their mixtures.
7. 7. The method according to claim 6, wherein the granular elastomer is polymerized in the gas phase, optionally, in the presence of an inert particulate material, selected from the group consisting of carbon black, silica, clay, talc, and its mixtures; and in that the continuous mixer has one or more rotors enclosed in a cylinder, this cylinder has one or more feed ports and optionally, one or more discharge doors, located along its length, and at least one capillary array or at least one profile matrix connected to the cylinder; and this continuous mixer is optionally coupled to a melt pump or to a single screw extruder.
8. 8. The process according to claim 5, wherein the dynamic vulcanization of the elastomeric phase is carried out in the continuous mixer.
9. 9. An article prepared according to the process of claims 1, 4, 5 or 8.