MXPA97006262A - Process for preparing articles resin depoliolefina thermoplastic permeability dehydrocarbon reduc - Google Patents

Abstract

The present invention relates to a process for preparing articles containing a reduced hydrocarbon permeability polyethylene resin, it is characterized in that it comprises: providing a thermoplastic resin composition, which comprises: a higher proportion of a polyethylene resin; lower of polyvinylidene fluoride, and a binding ratio of aluminum stearate, feed the resin composition to a heating zone, the zone being maintained at a temperature above the first order phase transition temperature of the polyethylene, what the feed composition is thermally plasticized, continuously pass the plasticized composition into a forming zone, where the plasticized composition is shaped to an article having first and second surfaces, cooling the article of the first surface to a temperature between the transition temperatures of f First and second order of the polyethylene, while maintaining the second surface at a temperature above the first order phase transition temperature, and then cooling the entire article to room temperature.

Description

PROCESS FOR PREPARING POLYOLEPHINE RESIN ARTICLES THERMOPLASTIC OF REDUCED HYDROCARBON PERMEABILITY DESCRIPTION OF THE INVENTION The invention relates to methods and processes for manufacturing articles based on thermoplastic polyolefin. The use of resinous organic polymers to manufacture containers such as bottles, tanks and other molded articles is well known. Plastic containers, which are made of most organic polymers, particularly polymers in the dominant hydrocarbon form, are easily penetrated and / or cracked by tension or swollen through oleophilic materials such as liquid and gaseous hydrocarbons, by example, solvents such as benzene, cyclohexane, xylene, chlorinated solvents and hexane; fuels such as gasoline, kerosene, fuel oils; oils such as natural fatty oils, lubricating oils, perfumes and agricultural chemicals. Depending on the particular plastic container, these cleophilic materials may adversely affect the container. For example, naturally occurring acids tend to cause stress cracking of containers formed from olefinic polymers such as PCB. As a result of these inherent deficiencies many containers must be treated with various agents, which impart varying degrees of impermeability. Sulfonation techniques have been developed as means to treat containers to reduce permeability and protect polymeric materials. Some of these sulfonation techniques are described, for example, in U.S. Patent 4,775,587. The surface modification of many plastics, whether they are rigid or flexible, with fluorine or other halogens has been found to be commercially advantageous since it is able to provide, for example, plastic containers having a reduced permeability although the liquids that have solvent characteristics and that have increased chemical resistance for various liquids and gases, which could otherwise react with the untreated container material. One such process and apparatus for the same is described in U.S. Patent 4,467,075, the disadvantages of these and other treatment processes that have surface modification as targets, are multiple. Some of the processes require complex apparatus due to the stages and conditions required by the process, which can produce fluorine in motion from a support chamber to a reaction chamber and return it to the reaction chamber. use of high pressures. Other processes provide a safety challenge. Reactive gases such as fluorine can be highly toxic, highly corrosive and irritating. Any process that uses relatively high temperatures, pressures and / or fluoride concentrations falls into the category of hazardous, increasing the possibility of fire or leakage. Finally, some processes create pollution factors due to the amount of fluorine and / or fluorine byproducts, such as hydrogen fluoride, which can be discarded after the fluoridation process is complete. The problems of the apparatus, safety and contamination of course, are interrelated due, in order to solve the last problems of security and contamination, the complexity of the apparatus is usually increased and, concomitantly, the investment and operating costs including the requirements of Energy. Other aspects of the industry, either sulfonation or fluoridation, have been generated by the phenomenon of "frequency stimulation" and the effect of lateral stress cracking and, therefore, the loss of penetration resistance with respect to base containers. of polyolefin. Another aspect for the improvement or reduction of permeability of hydrocarbon solvent in polyolefin containers has been to modify the properties of polyolefin resin through mixing with other resinous compositions. For example, U.S. Patent 4,410,482 discloses a thermoplastic composition useful for making reduced solvent permeability vessel articles, which comprises polyethylene mixed with an incompatible polymer such as a polyamide (nylon). The heterogeneous mixture, after molding, produces a laminar structure of reduced hydrocarbon permeability. In particular, such laminated articles derived from a polyolefin and nylon have been found to be useful as containers for liquid hydrocarbons, including fuel tanks for motor vehicles. Recent changes in gasoline technology have led to the addition of oxygenates, such as methanol, to an ever-increasing proportion of hydrocarbon fuels now on the market. The loss of a mixture of fuels of oxygenated compounds and hydrocarbons by diffusion through the walls of a container with a laminar structure of polyolefin and nylon in general, has been found to be sufficiently large to be unacceptable from an environmental point of view . In addition, as reported by the manufacturers, the polyethylene / nylon blends have presented some areas of interest, mainly: 1. The necessary amount of the lamellar polymer (for example nyl A for 1 = platelet ri. The limited ability to reuse and recirculate prlie iler.c / nyicr .. 3. Loss of mechanical properties due to the non-miscibility of the polymer; specifically in the "puncture areas" of the molded container. Polyethylene is a favored material used to make the containers described above. It is produced inexpensively and is easily molded or extruded. However, as noted in the above, polyethylene has serious disadvantages. When certain fluids such as hydrocarbon solvents are packaged in polyethylene containers, they tend to migrate through the wall of the container. This is due to the permeable nature of the polyethylene solvent. One aspect for reducing solvent permeability of polyethylene resin-based containers is described in Australian Patent No. 645,121 issued August 25, 1991. This patent describes the incorporation of a minor proportion of a thermoplastic additive into the polyethylene. . The additive is composed of a polyethylene resin, polyvinylidene fluoride and aluminum stearate as a binding agent, joining the polyvinylidene fluoride and the polyethylene thermoplastic. The mixture can be thermoformed to a suitable liner for drum and other material containers, thus serving as an extra measure of protection against penetration or can be formed directly in container containers. Based on the above work, it has been found that the additive described in Australian Patent No. 645,121 has a particularly good effect on polyethylene, especially high density, high molecular weight, thermoformed polyethylene (HMW-HDPE). It appears that after cooling during the transition from the molten to solid state, the HMW-HDPE chain molecules are able to arrange themselves through bending of the chains (layering) in crystalline regions. The extension of these regions (degree of crystallinity) increases when the closest chains can reach another (less degree of branching). The side chains interfere with the parallel alignment. The crystalline regions, interspersed as "esperulitas" through the amorphous material, increase the density beyond that of the exclusively amorphous material. The density value is directly related to the degree of crystallinity. C In addition, it has been observed that different KMW-HDPE with a widely similar molecular weight distribution (MWD) and low melt flow indexes (MFI), after rris-alize lower cooling velocity constants, have highly variable melting points. The points of? Different fusion was found to be correlated with different sizes of esperulitas; which, in turn, is controlled through the density of nucleation heterogeneities. This indicates that specimens with a high nucleation density will crystallize, on average, at a higher temperature than those with a low nucleation density. This, in effect, controls the laminar thickness of the polyethylene crystals. It is believed that with the control of temperature the laminar thickness of the polyethylene crystals and the surface density and, therefore, the degree of resistance to the penetration of hydrocarbon solvent can be controlled. Depending on the polymerization process, the polyethylene can have an inherent degree of crystallinity of 40 to 80%. Low density polyethylene, sometimes referred to as flexible polyethylene, has a crystallinity of 40-55% at a density of 0.915 to 0.930. The high density polyethylene has a figure? E crietalinidad of 60-80% to a deneidad of 0.942-0.965. The properties of polyethylene depend on the degree of crietalinity of the material. With the increase of the deneity (crystallinity) an increase also occurs in the following properties: 1. Crystalline fusion range. • 2. Tension at break '. Resistance to tension), rigidity. 3. Hardness and modulus of elasticity and / or torsional adhesion. 4. Solvent resistance. 5. Waterproofing to gas and vapor. The effect of crystallinity on physical properties can be observed as follows: AS THE PROPERTY INCREASES 'CRYSTALLINITY Density Increases Strength Increases Rigidity Increases Hardness Increases Wear / abrasion Increases Final elongation Reduces Impact Reduces Clarity Reduced The effect of crystallinity processing variables has also been observed. In general, higher melting temperatures result in slower cooling speeds, which increase the crystallinity. Rapid extinction results in minimal crystalline development while slow extinction results in maximum crystallinity. It has also been determined that in the additive of the Australian Patent described er. Above, the polyvinylidene fluoride resin (PVDF) is crystallized in at least three (3) crystalline forms designated alpha, beta and gamma. Normally, PVDF is crystallized from the fusion predominantly in the alpha form. The degree of crystallinity and the types of crystalline forms present depend on the processing conditions. A rapid cooling (extinction) of the melting bath prevents crystallization and promotes a smaller crystalline size. A slow cooling or heating below the melting point (annealing) perfects the crystallization process and relaxes the tension. In addition, the orientation below the melting point will improve crystallization. The additive of the Australian Patent is a non-lamellar product made from a mixture of (2) miscible materials (HMW-HDPE and PVDF) and a (1) compatibilizing polymer. (aluminum stearate), which serves to increase the miscible character of the HMW-HDPE and PVDF materials. Successful use? The active? E? E? The? Establishment? Of a homogeneous fungal mixture and? Compatible miscible polymers. It has now been discovered that if it is melted and the polyethylene extruded under certain conditions to perfect it. In the presence of the additive and the Australian Patent described above, are there any augmentative improvements in the permeability resistance? ? the solvent? and hydrocarbon. The invention comprises a process for preparing articles of resin, polyethylene and permeability. re? uci? a? hi? carcarburo, which buy?; provide a thermoplastic resin composition which they buy; a greater proportion is a polyethylene resin; a smaller proportion? e fluoride? e polyvinyl? ene; and a proportion? e binding? stearate? and aluminum; To feed the composition? Resin to the area? Heating, the area remained at a temperature above? The temperature? The transition phase? The first or? in? the polyethylene, so the composition The food is thermally plasticized; to continually pass the plasticizing composition to an area? e formation, er. On the plasticizing composition the shape of an article having first and second surfaces is configured, the article is cooled to the first surface at a temperature between the temperatures, and the fae transition of the first and second surfaces. or in polyethylene, my nr. r.-ier.e to the second surface at a temperature above the temperature? e transition? e phase? e first cr? er. You will have enough time to form crystals on the first surface; and then cool the article to room temperature. The term "major proportion" as used in the preamble means more than 50 percent by weight of the total composition as opposed to a "minor proportion" which means less than 50 percent by weight. A "proportion? E union" means approximately 50 to 100 grams per 100 weight? Polyethylene and PVDF mixes. BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a side view in transereal section, fragmenting a mole? eneambla? a? the apparatus? e mol? eo useful in the process? e invention. Figure 2 is a view of the? Emanual component? The apparatus shown in Figure 1. Figures 3 and 4 are transverse lateral elevations? The component? E? A? Or assemble? Or? The apparatus? Figure 1. Figure 5 is a cross-sectional side elevational view of a component of the assembly shown in Figure 1, along lines 5-5 and Figure 9. Figure 6 is a top view of the module of Figure 5.

Figure 7 is a cross-sectional side elevation of a portion of the apparatus of Figure 1, or a flow of the resin layer. Figure 8 is a top view of the plate, lower, and Figure 6. Figure 9 is a side view, enlarged in cross section, and a portion of a plate e? Below is Figure 8. Figure 10 is a cross-sectional side view along the line 10-10 in Figure 8. Figure 11 is a graphical representation of the results? e test obtained in Example 5. The apparatus and method are well known for extruding thermoplastic tubes in a single layer or multiple layers; see for example the Patents? and the Uni? oe Estates Noe 4,798,526; 3,949,042; 4,578,025; 4,657,497; 4,773,954; 4,798,526; and 5,019,433. The apparatus can be, in its simplest form, used for molé ear articles in a single layer. The apparatus can also be used as part of a molded-for-life apparatus, providing the shape for blow molding, or similar containers. Such an apparatus may comprise a head or a movable construction, wherein each block of AA receives a stream of thermoplastic polymer and forms a uniform tubular layer of a pariso. they can be combined in any number to form single-layer or multi-layer parisons, with each multi-layer parison layer being uniformly added to the outer surface of the previous layers.The geometry of the flow path? e the internal resin of each module is such that the extruded resin material is introduced to the module and the material flows along a path to an annular hole and then along a mandrel To ensure that the material flows efficiently from the point If it enters the annular orifice, a path is structured between the resin inlet and the annular orifice to conform to the ten? enciae? e flow of the stream? resin, avoid turbulent zones and Are you staying? or, so that the resin material emerges the annular orifice in a uniform shape and virtually without a line or point or sun? aura. The dimension,? The channel (height or width) can be varied over a wide variety? and it will be selected to fall as a module in relation to the other module? epen? ien? o? the viecoei? a? relative to resins and the speed? The production will be selected. The resin? E viscosity? The higher is to be passed through the channels, the greater the stress than the resin, and the lower is at the same production rates. ? r. the preferred apparatus, each module is coupled to the adjacent module in such a way that a thermal break exists between them. This thermal break allows a greater control? E con? Iciones? E temperature used to fall melting channel? E ca? A moulo. In addition, the modules and the manillary sections have their own temperature control system, this way, allowing a zone, temperature and variation to be the same. or with the need? The resin layer on the inner and outer surfaces is e ect. Referring first to Figure 1, a cross-sectional side view is shown, fragments an assembly apparatus 10. The apparatus 10 comprises a plurality? E? blocks? e block? e? 12, 14, 16, 18, 20,? are placed in a vertical stack to form a body? e? a? o 24 for the apparatus 10. The module 16, placed between the modules 14 and 18, is not seen in the fragmented view? Figure 1 for clari? A? ? the? drawing, but it is essentially the same as the illustrative modules. The modules 12, 14, 16, 18, 20 comprise, blocks of unintended damage made of a plate? E? A? O? O superior and a plate? E given inferior. The upper and lower damage plates are nested together and are thus maintained in the damage block assembly 24, as are the assembled modules, through a pluralism? The bolts are attached to the bolt 26, around the periphery, the apparatus 12. Les od le; be. held in a vertical stack through the connecting bolts, which together hold the terminal head plates 30, 32 with the interposed modules under sufficient pressure to prevent leakage of the thermoplastic material between the plates? e? upper and lower and between the modules. Above the plate? E terminal head 30 is a support? E? A? O Annex 34 and an? A? O? Nular 36 for the extrusion? E a thermoplastic parison as will be written more? Elante. Securely and removably fixed? Or? Enter a central cylindrical hole or channel? And extrusion through the bolts? And attach to the plate? E terminal head 32 is a cylindrical? rich ahusa? 42. Figure 2 is a side view? the man? rile 42, removed? channel 40 to see. The manillile 42 comprises taper 10 (in stages)? A manile body 44 having a first end 48 and a second end 50. A peetane 52 around the periphery of the body 44 at the end 50 it provides means for fixing the mandrel 42 in its place? entered the extrusion channel 40 with the bolts? and anchor. The mandrel body 42 has a concentric central cylindrical hole and is a hollow tube, the outer taper of the end 50 towards the end 48 in a step number is designated by the letters A-F. The number and width of the stage correspond to the number and width of the segments, the channel and the extrusion of the shapes for each of the modules, 12, 14, 16, 18, 2C, as discussed later. The mandrel body 42 is open at the ends 48, 50 to receive in its hollow part a moveable programming die rod 54. The movement of the damage rod 54? Entered the hole? The body? E manile 44 can be controlled by an electronic control, for example, a commercially available program? Graham Engineering Co., Inc., York, Pa. The controller, does not show? or in Figures 1-2, it can be mounted on the flange 52 to connect to the rod? 54? The rod? 54? carries a flow (gas) to flow Through the core, the parison that will be extruded and expanded in a subsequent blow molding operation, the fluid under pressure acts to maintain the shape of the parison before the article of the container that will be thermoformed is blown. Figure 3 is a transverse lateral elevation of the extrusion damage component 36 of the apparatus 10 shown in Figure 1, and shows that the lower extension of the damage stem 54 is a raisin 55, which moves to expand or contract the channel? extruder 40 in the? or? a 36 of the orifice 56, thus adapting the control of the thickness of the wall of the parison. The pin 55 moves in and out of the hole 56 of the damage 36 at the same time that the connected die rod 54 moves similarly within the hollow core of the mandrel 42. As shown in Figure 4, the pin 55 has been retracted to increase the wall thickness of the parison. During operation, the wall of the parison can be continuously varied in thickness. For example, the thickness of the parison portion can be greater for blown vessel walls, which have the highest blowout ratios, so that the parison is molten or blown? So that the article? e resulting container can have a thickness? e stop? uniform. In this way, the portion? E? I? E? Maximum? The container will be molded or blown from a thicker part? The portion? E stop? ? e parison. The apparatus 10 can be employed as the extrusion component and is a conventional blow molded device, which receives a bath, melt, thermoplastic resin, and a source. and melting such as one or more thermoplastic extruders and? scaven? or a parison? e a single layer or? e multiple layers? the? a? o? 36 towards the mol. The thermoplastic melting bath or extruder is received in a separate form in an extrusion channel or through the assembly of the inorganic modules that are purchased in the body. ? e? a? o 24, through a thermoplastic melt feed pipe. Preferably, there is an individual feed pipe that communicates between each module and the source or melt or sources (extruder) so that each die block module serves individually with the resin melt bath. In Figure 1, only a plurality of feed pipes 58 are shown for illustration clarity, such as a conduit between the source of melting bath and resin and a channel? E? Distribution? Constant volume 60 formed by the eneamble the module 20. The resin can be flowed down to the joint assembly, which is a pump, the displacement, and the constant volume. The speed? The pump is controlled by supplying the melting bath and resin to the assembly, the tube at a pressure? The tube 12, 14, 16, 18, 20 contains within it a channel? E? Istribution? Constant volume 60 and a term? E a pipe? E feed? E bath? E fusion? E resin such as a pipe? e feed 58 connects to the channel? e? distribution 60 for the supply? and finally resin to the channel? extrusion 40. The ??? annular expressions 62 are slots? e air and serve as thermal rupturae between the assembly assemblies? the body? e? a? o? 24 and the plates? e terminal head 30, 32. These thermal ruptures are open to the atmosphere at the outer periphery? e the modules to facilitate the transfer? The heat is the expression and the molecules. Similar thermal breaks 62 are also located between the mole as shown in Figure 1. The winding of the modules 12, 14, 16, 18, 20 between each other through the thermal ruptures 62 provide the apparatus, in which the cerner! Is the thermoplastic fluid flowing in???????? The thermal insulation of the modules can be achieved by the incorporation of the thermal insulation between the modules, suspension in the epreeion, and the isolation of the modules. through the? iscos? and insulation 64 avoids the rational transfer and? convection? of the thermal energy between the modules, which would otherwise result in con? iciones? They can be used in any material, thermal insulation known as insulation, and insulation such as fiber, glass, asbestos, and similar materials in a certain way. • Self-support (rigid or semi-rigid) • Isolation and isolation should not fill the "62" impression because the rupture is necessary, a placement is filled with material. and insulation, such as fiber? and vi? rio,? enter the? epre The ring between the modules could not really be the zone and the modules, and could it result in the? egration? of any resins sensitive to high temperature? I enter a module adjacent to a module? s operation at a temperature? e? e? ation? e the sensitive resin. The separation and thermal insulation? E fallen member? E module that developed? The body? E? A? O? 24, with hollow? E air and the? Ects? The insulating material 64 allow the efficient removal? the excess heat from the left and right of the module and close to the control of the separate and individual resin melting temperature at the extrusion point to the extrusion channel 40. Does the thermal break prevent root heating? e-the adjacent layers to help maintain the? erential? temperature between the adjacent layers, as much as 150 ° C. This obviously is very important when the material and the resin layer are relatively warm and require temperatures. Preferably, there is an area? E contact? E minimum surface between the modules to avoid thermal tranemisation between modules. This aspect is advantageous when the adjacent layers of a multiple layer that is being extruded, or require temperature-dependent con? Icions for extrusion under melting.; Particularly, how much does one require a temperature that could cause the? egration? of the resin that is expressed to the canal? s extrusion 40 and over the man? rile 42. A non-efficient temperature control, the product and the multi-layer extruded layers can be "erect" to the point? re? uci? a. Critical to the process? E the present invention is the control? E the temperature? The man? Rile 42. In order? To create a thermal profile through? The thickness? E the layers? E parieon in? Ivi? Uales, the which will facilitate crystallization along a surface of the polyethylene layer which is incorporated in the parison (or monolayer resin), the mannile 42 is maintained at a temperature above the temperature? The first phase in the layer, the resin, and polyethylene, during a period greater than the temperature, the module associates 12, 14, 16, 18, 20. man? ril 42 was previously? written as a hollow body, and? intro? his body could mount a plural? ? e heat? ers and sensors? temperature for control, one to fall to? the stages? designated by the letter A-F (see Figure 2). These controllers for heating create separate heating zones for one of the AF stages, the manilile 42 for maintaining the surfaces of the inner layer or layers (or monolayers)? At a temperature above the temperature, the transition temperature makes the first temperature, while the other surfaces, the layers, and the parison or monolayers are cooled to a temperature of below? e the temperature? e transition? e phase? the first or? in. Since the temperature? The module associates 12, 14, 16, 18 or 20 is re? Uce below the temperature? E transition? E phase? The first or? In? E composition? E polyethylene , a solvent-impermeable zone is formed through the slower crystallization of the polyethylene layer on the surface adjacent to the mannile 42. Ca? a mole? 12, 14, 16, 18, 20 it is associated with inorganic metals to heat the module to a temperature advantageous to the extrusion? a resin layer? a? a. Figure 5 is a lateral elevation in cross section - Module 18 shows "Removal" of the assembly, the block, e? 24, and fixed on the outside with a heating resistor. 70. The heat resistance 70 is fixed in close contact with the wall. external peripheral? the module 18 annularly configures, in order to transfer thermal energy to the module 18 through ra? iación and / or con? ucción. The me? Ios? E heating? The heat? Re? Etence 70 can eer? Ivi? I? Os in a plural? He heaters separate mounts on the outside - the module in order to substantially enclose the mole. Figure 6 is a view? Is? Up? The 18th module, do you carry such me? Ios? The warming that you have in a plural? Five heaters, zone 72, 74, 76, 77 and 80 together with electrical power supply separate 82, 84, 86, 88 or 90 to activate the associated heat. or with them. The heaters, usually in the area, heat the steel sections separately from the steel tempera- tures, and appropriate steel for the different resins that flow through them. Unusual modules. The correct equilibrium? E? E? Thermal energy? Is? The heaters and? Is? Ation? E electrical energy? Is? The open annular grooves or? Epressions 62, assures the control? The temperature is low, so that resins with very high flow temperatures can be extruded through the pipes and over the manhole. Action The elements heat up the zone, and the elements such as the heating elements, and the resistance 72-90 can be and preference are unusually energized and energized. to maintain a temperature? e pre-eminent fusion in the zones? the? channel? e? istribution 60? e fusion? e resin. Thermocouples can be associated, such as thermocouples 92, 94, 96, 98 and 100 with one of the heating elements? e zone? e module as part of an electric circuit? and energization and? conventional energization for ayu? to control the temperature? e steel? esea? a. Figure 5 is a cross-sectional elevation? The module? Block? E? 18. 18. Modes 12, 14, 16, 18 and 20 are represented by the 18th module and make an upper plate 102 and a lower plate 104. The upper and lower plates 102, 104 fall one has a generally flat body. The plate 102 has an external surface 106, an internal surface 108 and a central opening 114 through the module communicating between the surface 106 and 108. The opening 114 is limited by the stop? lateral 116 formed by the body? e mole. Similarly, the lower? Oid plate 104 has an outer surface 110 and an inner surface 112 with a central opening 114 communicating between the surfaces 110, 112 and? By a wall? lateral 116? the body? e mole. The central aperture 114? E plate? E? E? E mole 102, 104 is in fixed axial alignment with the central aperture? The other plate? E? A? O? E? Mole? The tube in the stack vertically stacked the body 24, to form a continuous continuous extrusion channel 40 and a substantially uniform diameter. It fell to plate? E? E? And a module such as 102, 104 is placed as a upper limb and a lower limb in a pair between the vertical stack. The module 12, 14, 16, 18, 20, and the internal surface between the plates? E? And? The module 102, 104 such as the surfaces 108 and 112 support an annular seal 118 in a slot? e seal that works to avoid any? errame? the channel 60. The adjacent surfaces 108, 112? e the plate? e? a? o? top? 102 and the plate? e? a? o? 104? The two sides are arranged in a line 109 and together form an annular channel 60. The upper surface 106 of the upper plate 102 supports a flange 120 projecting towards up around the central aperture 114. The tab 120 is a size and configuration to coincide with a? epression in the plate? e? or? lower? the adjacent module 16 The? Epression on the plate? E? A? Or? The lower module? The horizontal module 16 is identical to the? Expression 122 shown on the lower? 104? Plate? ulo 18, which receives the tab 120? e the next plate? e? or? higher? The lower tube 20. Through the intercommunication and the invisible tabs, it fell on the radio with the airscrews. , 14, 16, 18 and 20 are joined together in the stack stacked? The body? The block? E? A? O 24 to ensure the axial alignment? E? Aperture 114 to form the channel? extrusion 40 which has a uniform thickness through the block? e? a? o 24. In this way, the modules lock to form the head? e? a? o? The manile, cylindrical, align? oe. The physical structure of the modules and their method allows the formation of the thermal zone and the layer that will be extruded and the alignment of the openings. to form an extrusion channel 40 axially aligned, or lie. It would channel the shape of the plates, the upper and lower plates, 102, 104, the eneamblaus module, and enter the head? E? A? 24 eetá? Radically disposed around the extruded channel 40 with an inlet to the bath, the melt, and the resin 130 in the term? the con? uct? e feed 132 and an orifice? a? e bath? ring fusion 134 on the inner periphery? channel 60 through the wall? lateral 116. The orifice? e bath? fusion 134 opens towards the channel? extrude 40. Channel 60? the preferred apparatus 10 is a fixed, predetermined, free volume structured in contained movement. as or motionless separates. During operation, the apparatus written in the above functions to manufacture a parieon configured as a tube, a single layer or multiple layers (re? On? O or oval)., the number? e assembly modules and? e operation? determine? the number? e layers in the parison? e products. In this way, the apparatus can be used to produce a multiple layer or a single layer with a wide variety? The materials are thermoplastic, including the materialee e reeina extruiblee. Examples of such resin include ethers and ethers and cellulose such as acetate, ethyl cellulose, acetobutyrate and acetopropionate.; polymers of vinyl and vinyl and copolymers such as polymers and copolymers, and vinyl chloride, vinyl acetate, vinyl chloride, vinyl alcohol, polyvinyl alcohol, polyvinyl butyryl; and olefin polymers and copolymers, such as ethylene, propylene and butylene; polymers and copolymers, styrene, 2-methylstyrene and mixtures thereof, and elastomeric copolymers; polyamines, interpolyamics such as polyhexamethylene-a? ipami? a, polycaprolactam, polyun? ecana? a, polyhexa-methylene-sebaca? a; polycarbonates; polyalisols, polyethers; polyurethanes; polyesters; natural and synthetic elastomers; thermoplastic fluorine resins; resins? and silicon and elastomer and the like. These thermoplastic resin materials can, of course, be used in admixture with material, filler, plasticizers, colorants or other organic additives, with the proviso that they do not avoid low extrusion. fusion. In the preferred process of the invention, various thermoplastic materials, such as those written therein, are combined to take advantage of the thermoplastic, e ectible, one-sided property. Is the polyethylene resin modified with the aid of the Australian Patent, described in the foregoing, to reduce the permeability? ? e eater? and hydrocarbons. By way of example, the property is eseable, it can be mentioned mechanical resistance, resistance to shock, property is thermal, traneparency, opaque, chemical resistance, waterproofing. to? to liquids, gases and odors, easy? ? Capability? ? work to receive painting or? ecoration, etc. It is also contemplated in the present invention that a multi-layer parison of the thermoplastic resins can be made with a solid layer between the thermoplastic layer. For example, a multi-layer parieon can be made of a mutually compatible resin or resin interposed between the layers and the thermoplastic resin, which, in the case of the interposed one, would normally be possible. a? hurt between you. In this way, it is possible to form products that combine multiple layers or materials for their own properties, without considering whether or not these materials are capable of being directly united with one another. the coextrusion. As shown in FIGS. 1-7, the mannil 42 is fixedly positioned between the extrusion channel 40 in a separate relationship with the stopper. lateral 116 to? ect a continuous, vertical, annular or cylindrical extrusion channel 40, closes on the upper side through the plate? e terminal head 30, and open at the bottom through the? Extrusion 36 and communication with a hole orifice 134. The thermoplastic bath under the pressure enters the channel, and the extrusion 40 is the annular hole 134 to be received. On the ladder manile? 42. An advantage? The apparatus? described in the above is in eu habili? a? To operate at relatively low temperatures, it is 351.53 kg / cm2 (5000 psi) or less. This advantage is as a result, or in part, of the style, the manile, and the placement, written in the foreground, which can provide a free parison, even at relatively low pressures. It would channel the? Istribution 60? Is load the bath? E fusion to the canal? E extrusion 40 and on the manilile step? Or ahusa? Or 42, in order? E obtain a thickness? E layer? E parison This is the ideal thermoplastic charge in a sequential, staggered way, that is, the first or the lowest module provides the bath and fusion for the innermost layer, the parison. The taper will stagger? Or? The man? Rile 42 and a uniform cylindrical gauge in the channel? S extrusion? 40? Speed? Is the flow? Velocity? uniform laminar constant, in the in? ial layers? during extrusion. Progressively, the upper tube fell through the aoecious hole, or introverted the flow to the wide-gap, the channel 40 created by the stage, the man-hole 42 until the last orifice. The most superior or intruder the outermost layer, the parison formed before its passage towards the extrusion 36. Advantageously, the extruder? e ca? a capa? e parison is controlled so that it? s entered the range? e 1 to 100 thousand. The thickness, the parison, and the uniform layers are also controlled by the use of the manilile ladder, which works to maintain a uniform resin pressure across the length of the pipe. • the extrusion channel 40. The thickness can also be control or adjust the velocity, the flow, and the resin layers, the veloci? a? and higher flow rates to layers máe grueeae. Since the bath and melting resin is supplied, it is the annular orifice 134, which is the same as the assembly, the resin flows on the surface, the manillary is 42 a stage adjacent to the particular orifice 134. The flowing reema emanate? oee? is? the plural? The holes 134, can be pressed, iferented. The equilibrium? Esion occurs as the separate flows unite on the mandrel 42. By varying the pressures of the resin flows separates, the thickness? E the layers can be controlled in relation to each other? The annular channel 40 which gouges the mannile 42. The pressure euminietro increases the thickness increases and the layer supplies and relieves relatively the thickness of the layer previously extruded. The pressure? E supply re? Uci? A? Decreases the thickness? E the new layer will supply, while the thickness is relatively increased? E the layer previously extruded. The annular stages AF on the mannile 42 opposite the inlets, the orifices 134 on the assembly side, have depth and are insufficient to allow the layer or layers extruded previously on the manile (what is there) are moved towards the inside against the countercurrent portion? e? meter re? uc?? o? the man? rile 42 to provide a space for the last funnel that flows through a hole 134 and into the space between the previously extruded layer (if any) and the surface 116? the cylindrical hole? the channel 40.

The length of the stages is selected so that the layer will have the relative thickness, that is, below, the hole 134 will fall. This compensates for the fact that the thickness of the layers increases as they move rationally into the stages and their circumference is resolved. As shown in Figure 8, the stages on the mannile 42 occur in a smooth curve at the level of the orifice 134, or preference to an upstream instability in the direction of the extrusion. , equal to the mirror, and the reef, and the reef layer will enter. The curve is not sharp, the preference is for a smooth traffic between the stages to reduce the interruption to a minimum, the flow of the resin that hits the manilile 42. This structure eliminates the Possibility? Is it a watertight zone in the stage and does it help to maintain the speed? The constant and uniform flow would be in the apparatus 10. Figure 8 shows a view "above" the channel "distribution" seen in Figures 1-7. It enters the bath, the melting resin 130, is loaded into the bath, and the resin is melted in the channel 60. Preferably, a separator or blade is mounted on the floor, the opposite channel 60. At the entrance to the 130, the flow, a half? in fall? direction. The details are shown in Figure 10, an "agrarian" view, the "schist" or "311" instead. It is possible to place a temperature sensor 313 to perceive the temperature? E ree? Esvia? A. A mita? The resin will flow? is the point 130 as it is injected by one of the arrows in Figure 9, and the other half? The other arrow will flow in the general direction. I fell mita? The resin partition will eventually flow into the annular orifice 134. The separator can be movably placed in order to adjust the flow, so that more flow is? irigi? or in a mita? that in the other half, to compensate for the? equilibriums in the natural flow? I enter the passage. As shown in Figure 8, channel 60 comprises four zones, ie, one enters the outer boundary, and one imaginary line closes 300 that writes a closing, null line. The outer zone 302 is united most of its outer edge by the line 300 and at its inner edge by a line 304, which is a smaller circle than the one created. on the line 300. The outer zone 302 has a substantially uniform immense as it extends into the?? como como como como como como como ire ire ire ire ire ire ire ire ire ire ire ire ire ire ire ire la la la 130 to point 305. Point 305 is a point located 180 ° through the entrance 130, where the arches-ejection 306 and 308 intersect. The arches 306 and 308 fall • one originate at a point on line 300 approximately 150 ° left and right at entrance 130 and through line 304 at point 305. The area 302 begins to decrease in size along the boundaries of the arcs 306 and 308 and in actuality? terminates, that is, decreases without point to point 305. In this way, the external zone 302 in reality? ee? ivi? e in? ee? m? ee? m? ee? ee? m? ee originate? or in? in? 130 and end? o? in point 305.??? Does not communicate with the other mita? The zone 302 through the point 305. During the operation, the outer zone 302 is a primary resin flow path, substantially circular, eccentric with respect to the central axis of the extrusion channel 40 with the center line of the zone 302. located on the radial line extends? that is? the center? channel 40 to line 300 and e? stops? the canal? and extrueión 40. The resin fun? i? a flowing through? e enters? at 130 it fills the primary channel? e zone 302 and flows? it? s zone 302 radially through to? e through a section? e narrow gate. The flow direction is to the extrusion channel 40. The narrow gate section i? Tied in the? Ower? Of FIG. 8, is an annular area 307. On the inner edge of the line 304 is the area? e compression set to 307. Zone 307 is? enominated? a? e? a? ey? e? e? e? e zone that has a substantially lower height than zone 302. or zone 312 that limit their internal appearance. The area 307 has an annular shape? Efin? A on its inner edge through an annular zone 312.

The area? E channel? E the area 302 ee eccentric to the area 307 to provide a gate? E variable width with the maximum width? E the gate at the entrance? 130. Eeta variation in width reetringe the flow? Is? E? it enters 130? directly through the gate into zone 312, thereby channeling the resin around the channel into zone 302 to fill zone 302, so that the resin flows to the ring of the zone 312 essentially and uniformly around the ring of the channel 60. All the resin flowing through the inlet 130 moves towards the zone 312 at a speed? essentially uniform around the circumference? the ring? in zones 302 and 308, since the retrict? e channel? e zone 308 modifies the velocity of the flow flowing through? Directly between line 300 and zone 312 and allowing for an? ional emergency, so that the flow should flow around the outer circumference? channel 60. The linearly flowing reef? Zone 308 fills a ring with a circumferential balance or transition, which is an annular zone 312 that roasts to the bottom, the cone truncates or leads to orifice 134. The purpose The annular zone 312 is to allow the equilibrium of the pressure gradients in the resin and to ensure a uniform parallel volumetric flow of the resin through the cone truncate. This helped avoid the lines? E point.

The area? E canal? The truncated cone? Or 320 is open to receive the restroom? E fire? E resin? Ee the annular zone 312 and change the? Direction? E flow up along? The truncated cone ?or; see Figure 5. The area? e channel? truncated cone? or 320 opens to hole 134. The width? e this zone? and passage 320 increases as the? ameter re? uce moving is the zone 312 towards the orifice 134 to provide an essentially constant cross section. In this way, the resin flowing into zone 320 is not restricted. A constant volumetric flow is above all compensated for the increase in pressure in the zone 320 in a significant drop. It is essential to avoid the line, the point in the parison that will be extruded. In summary, the flow path of the resin in the apparatus 10 includes a portion? Etribution located in a plane perpendicular to the axis? The manile and a fruetoconical portion extending? Upward? it is the plane downstream and downward towards the orifice 134. Figure 10 is a transverse side view along the lines 10-10? e Figure 8 and shows the additional details of the distribution channel 60. The following preparations and examples describe the manner and process for making and using the invention and establish the best mode contemplated by the inventor to carry out the invention. PREPARATION An additive is prepared to mix with a polyethylene resin, mixing polyvinylidene fluoride (PVDF) and aluminum stearate with thermoplastic HMW-HDPE. The PVDF can be either in the form of powder or a tablet. The components of the mixture were combined together in the following ratio: HMW-HDPE 23.60 kg PVDF 21.79 kg Aluminum etherate 56 gram / t. After mixing the additive, a mixture or subsequent mixture with a polyethylene resin is suitable. The mixture or subsequent creates a thermoplastic composite material for thermoforming articles, such as containers that are resistant and have a hard and fast penetration through their walls. It is preferred that the mixture be eroded with the thermoplastic and polyethylene, the additive comprising from 3 to 30% the total composition of the resin. TEST DETAILS Three drums manufactured from HMW-HDPE (two of them mixed with the antifreeze) were tested to determine the amount? ? and penetration? and? carbcarburo through? e stop them? the drum.

The drums were filled with xylene and then stored for a period of one year. The data which reflect the percentage of fluid penetration through the drum were compiled on an intermittent basis. Drum # 1 was a control drum that did not possess any additive that was resistant to penetration. Drum # 2 produced 3% by weight? Eective to penetration? E the previous Preparation. Drum # 3 had 6% by weight? Eater resistant to penetration? E the above Preparation. 1 year until 30? Ies / 50 ° C 12 weeks / 50 ° C temp. environment Drum # 1 0.7% loss 2.08% loss 6.0% loss 3% Drum # 2 0.4% loss 1.1% loss 4.7% loss? to 6% Drum # 3 0.19% loss 0.58% loss 4.6% loss As you can see, drums, manufactures, and HMW-HDPE that contain the substance, exhibit a resistance to penetration, and a hydrocarbon. The amount is carried in drums so that they are in accordance with the regulations of the Department of Transportation, which is set at a maximum of 0.5% and 50% at a time. Thirty years for hazardous materials, and a 2% at 50 ° C for a period of thirty days for non-hazardous materials.

EXAMPLE 1 A polymeric resin was prepared, with 5 layers with a head, and five modules as described above and as shown in the annexed drawings. Figures 1-10. In module No. 1 (for the base layer on the man-made component) a polycarbonate resin bath (LEXAN 154, General Electric Co. ). In the following 4 modules, sequentially, melting baths of a polyolefin resin bonding layer were introduced for a subsequent tenter.

(E-310K), a random ethereal copolymer and vinyl alcohol (EVAL-F; Kuraray Co., Ltd., Evol Co. Of America, Omaha, NE), a second resin bonding layer (Adner VP-600; a polyolefin of adhesive (acetate? e polyvinyl / copolymer? e polyethylene) Mitsui Petrochemical In? uetriee Lt?., Tokyo, Japan) and HMW-HDPE to which was added 6% by weight? e the Written Preparation? in the above with mixing? The inorganic modules were heated to a temperature, the heat for falling material, the resin, and kept at the temperature selected to supply the resin at low velocity. The pre-eminent flow to the channel, and the extrusion to the sequential one, form the parison of multiple layers. The total re? Ection time of the bae layer in the channel? E extrueion is about 1 second. The product structure is uniform in weight across its length, free of bubbles (to the naked eye) and there is no line visible point.

The product was obtained at a speed? ? e313.26 kg / hour (690 pounds / hour). The temperature? E? Next table with the approximate thickness of the extruded layer. TABLE MODEL? E Percent? Molecule Resin Temperature (° C) Thickness? Tube 1 Polycarbonate 260 75 2 E-310K 218 5 3 EVAL-F 218 5 4 VF-600 218 5 5 HMW-HDPE with 6% 215 10 by weight? The additive? E Preparation The parison was used, selectively, to cool First the modules below, the temperature, the lower portion, the mannile, so that the surface above the manometer is cooled more slowly and maintains a temperature above. The temperature is the first transition for the resin, while the surface near the surface of the module cools down more rapidly to a temperature below the temperature of the transition. the first order for that resin.

The parison obtained can be ground or blown through the method described in the patent? E loe Eeta? Oe Uni? Oe 4,472,343 to obtain container containing which is shown to be? And waterproof? improve the solvent. EXAMPLE 2 This example is not an example of the invention, but rather is made for purposes of comparison. A 4-zone conventional screw extruder was charged, heating and a 2-zone heating zone with resin, and HMW-HDPE containing 6% by weight. Preparation, eupra, and a parison was extruded and a single layer under the following con? Iciones? E temperature. Temperature (° C) Extruder? E Zone # 1 171 Zone # 2 176 Zone # 3 176 Zone # 4 182 A? Fit for Head 176 Accumulate? Head? E Zone # 1 190 Zone # 2 190 Head? Damage 196 Temperature? E Cool? Molle 15 Parison extrude is molded? It was blown to obtain a container (90 gal. tank) characterized in part by. a rugged outer surface? written as an appearance? and "cottage cheese." This is believed to be partly due to the flotation, the refueling, the PVDF, the significant mixing in the extruded composition, the internal surface, the eoplane contents. The cooling was effected through rapid cooling of the article at room temperature. EXAMPLE 3 The extrusion and the molding were repeated by eoplane or Example 2, supra, using the mixture containing 6% of the Preparation, supra. ,? eecrita in the above, except lowered the following con? iciones ?? e temperature. Temperature (° C) Extruder? E Zone # 1 213 Zone # 2 213 Zone # 3 213 Zone # 4 216 A? Fit for the Head 213 Accumulate? Or? Head? E Zone # 1 216 Zone # 2 216 Head? Damage 224 Temperature? E Cooling? Mol? 15 Cooling was performed as in Example 2, supra. , except that the first (internal) surface - the parison was maintained at a temperature between the temperature, the transition, the first temperature and the temperature, and the transition from the second to the second (149 ° C), while keeps the second external surface (at a temperature below the temperature? e transition? the first or? in (190 ° C),? for a sufficient time to obtain the crietalization? the PVDF in the e? Compared to the container? Example 2, supra., The container blows (one gallon per tank) exhibits an end? O? S smooth outer surface.The microscopic examination? E a section? E stopped it? shows a highly crystalline layer (PVDF) a.relative to the external surface.the container.To test the characteristics? e permeabil? a? e the previous articles prepared in Examples 2 and 3, were tests used? and penetration in a furnace? e circulation, at 50 ° C, compare the HMW-HDPE does not treat the prior art (without a? Preparation) with the mixtures? e 6%? e the Preparation, supra. For example, they use xylene as the solvent and the hydrocarbon. The results of the test use xylene as the hydrocarbon content, are shown in the following table.

TABLE Percent? E Pér? I? A 30 Days 12 Weeks Example 2 0.4 1.1 (comparative) Example 3 0.19 0.58 (invention) Control (without additive) 0.7 2.08 EXAMPLE 4 The procedure was repeated, Example 3, supra.

The results? The test? E permeabil? A? They use oil and heating as the solvent and hydrocarbon stored in the test? e permeabili? a? are shown in Figure 11, a graph that reports permeability? ? the HMW-HDPE control (Example 2) and with 6 percent ea? tive (Example 3) or 20 percent ea? tive (Example 5) and compared to a container? e HMW-HDPE? e fluoro surface The prior art: F3) EXAMPLE 5 A mixture was prepared and HMW-HDPE to include percent in peeo? E the Preparation, supra. A portion of the mixture was extruded and blown to obtain a container "A" followed by the process, Example 2 above (without invention), another portion was extruded and blown to obtain a container "B" container according to the procedure? Example 3, supra. , (the invention). For control purposes, a third container was made to contain "C" from the base resin HMW-HDPE (without the addition of the preparation). The three containers containing it were tested to determine the permeability. to perchlorethylene. The following protocols were used: test: Perchlorethylene test medium Specimen thickness 0.090"Test duration twelve (12) days Test temperature 72 grams (f) Smoke? 50% RH Metrics Daily, • For a period of time (12) • Instruments • Test Machine • Hume • a • Control • Mitituoyo Laboratory-CCM • Percentage Percentage • Weight • Percentage During the 12-year period, it was as follows: Container? Percent? e Pér? i? Container Container? A (invention)? 0.02 Container? Container B (invention) < 0.02 Container &Container C (control) < 0.28 Container &Container D (Control) < 0.28 The effect of the invention under proprietary? is mechanical? e the containers? e also test It could be done through the evaluation of the sample, in this evaluation, the use of? iscos? and the extruded resin to close the mouth? a Mason type jug, containing? or approxima? ament e 1/2 full? e perchlorethylene. The isakes were allowed to stand for 12 hours and absorb the vapors and perchlorethylene at room temperature. The peso? The? Isco reepon? E the serious? I used to know that the? isco? e? e? e the penetration with the vapors? e solvent, they form a "cup". The deep? The glass is an in? ication? the? e? p? a? in the property? is mechanical. The result is that they move as follows. Cup in cm Reeina? Container A (invention) 0.20 cm Reeina? Container B (invention) 0.04 cm Reeina? Container C (control) 0.68 cm Resin? Container D (control) 0.66 cm Improvement? E cristalini? a ?, through the procedure,? ramically effects the delay? the penetration and re? uce the per? i? a? e? the? property? is mechanical? ebi? o to the exhibition? the solvent? and hi? Rocarburo

Claims (9)

1. CLAIMS - 1. A process to prepare articles that contain a polyethylene resin and permeabili? A? He has a carcinogen, he is characterized by his purchase; provide a thermoplastic resin composition, which they buy; a greater proportion is a polyethylene resin; a smaller proportion? e fluoride? e polyvinyl? ene; and a proportion? e binding? stearate? and aluminum; To feed the composition? Resin to a zone? Heating, the area remained at a temperature above? The temperature? The transition phase? The first or? in? the polyethylene, so the composition The food is thermally plasticized; to continually pass the plasticizing composition towards an area of formation, in which the plaetificat composition is formed to the form of an article that has first and foremost euperficiee; Cool the item? s first surface at a temperature between the temperatures? the transition? e phase? the first and second or? in? the polyethylene, while keeping the surface at a temperature above? the temperature? e transition? e phase? e first or? in; and then cool the article to room temperature.
2. 2. The process? E conform? with claim 1, characterized because the polyethylene resin is a high molecular weight polyethylene resin? high?
3. 3. Does the procedure conform? with claim 1, characterized in that the heating zone comprises a heating zone in a thermoplastic extrusion for the extrusion and the zone? e configuration is the? ex? or? extruder.
4. 4. The process? E conform? With Claim 3, it characterizes because the extruder extrudes a single layer extruded product.
5. 5. The process of conformity? with claim 3, it characterizes because the extruder extrudes an extruded product in multiple layers.
6. 6. The process? E conform? With claim 5, it characterizes because the polyethylene resin is extruded as a layer, the extruded product is multi-layered.
7. 7. Article is prepared through the process? with the reification 1.
8. 8. Article?? conform? with Claim 7, characterized because they are recipients.
9. 9. The process of compliance? with claim 1, characterize? a? emás because they buy and eoplate the item to form a recipient.