MXPA96006224A - Degradable polymers and polimeri products - Google Patents

Abstract

This invention provides polymeric, plastic, degradable blends and methods for making the same. The mixtures comprise a polymeric material and an organosol lignin. The invention also provides articles of manufactu

Description

DEGRADABLE POLYMERS AND POLYMERIC PRODUCTS CROSS REFERENCE TO THE RELATED APPLICATION This is a continuation in part of the Application Serial No. 08 / 258,280 filed June 10, 1994 which is a continuation of Application Serial No. 07 / 867,718 filed July 9, 1992, now US Patent No. 5,321,065 issued June 14, 1994.

BACKGROUND OF THE INVENTION Polymer blending has become one of the most commercially important and inexpensive ways to develop new materials from easily available base polymers. The main purpose of the polymer mixture is the production of good performance materials at a reduced cost or the modification of some specific properties of the polymers. This is achieved through the infinite possibilities of mixing, the ability to use existing equipment, flexible processing, and the ability to combine expensive polymers with ordinary and abundant ones. REF: 23691 Polyethylene is produced by polymerizing ethylene gas and the result is a joint union of the ethylene molecules in long polymer chains. The most common additives are heat and light stabilizers, slip agents, antiblocking and antistatic agents, flame retardants and pigments. Antioxidants are usually added to protect against thermal oxidation which can be a problem during processing. Photo-oxidation or light oxidation that occurs when natural PE is exposed to UV radiation is more frequently inhibited by the addition of carbon black and / or UV stabilizers. PE is classified as either low and medium density LDPE (LDPE and LLDPE) or high density (linear) HDPE (HDPE) based on the ASTM designation. LDPE and LLDPE have been used in several applications: film and coating, household utensils, lids and containers, packaging materials, wire and cable sheathing, rotational molding, powder coating, pipe extrusion, waste bags or garbage and extrusion coating. The main processing techniques used to convert HDPE into terminal products are blow molding and injection molding for containers and lids, films and large containers. The ethylene (vinyl acetate) copolymer (EVA) is generally obtained by adding vinyl acetate to PE. The EVA is stronger, more flexible, softer and less resistant to heat than LDPE. Being softer and more flexible than PE, copolymers are often competitive with rubber and plasticized PVC. At higher levels of comonomer incorporation, EVAs are used as wax additives and as components in other formulations for hot melt coating and adhesives. In these applications, the copolymers provide strength, improved barrier properties and improved processing characteristics. Polypropylene (PP) in its natural form is particularly vulnerable to degradative attack by oxygen and sunlight. Stabilizers have been developed that allow the PP to maintain its balance of good mechanical properties at low cost, and do so in several severe environments. Phenolic antioxidants have the main function of reacting with the peroxy radicals of the polymer to form more stable radicals, and thus stop the oxidative attack on the chain. To protect the polymer against prolonged periods of external exposure to UV radiation, UV absorbers are added before processing. These absorbers are colorless and transform UV radiation into a light with a longer, harmless wavelength. The most common classes of UV additives include benzophenones, benzotriazoles, salicylates and phenyltriazines. Also certain nickel salts provide some degree of UV absorption and act as a scavenger of free radicals, preventing the propagation of the photodegradation process of the chain. The PP finds applications in molded products for automotive uses and in appliances, packaging, fiber and fibrillated films, microporous filters and desalination equipment, spun fibers, film and sheet and non-woven fabrics. Styrene is used mainly for the manufacture of thermoplastic resins of which polystyrene (PS) and polystyrene copolymers are the most important. Polystyrene is the third most widely used thermoplastic resin, surpassed only by PVC and PE. The majority of the polystyrene is processed by rotation and injection molding, extrusion and thermoforming. Two pieces of polystyrene are used Currently: glass and impact polystyrene. Both types are used in applications in household utensils, packaging, appliances, wall coverings and many specialty applications. PVC is the most highly modifiable plastic, known. The products can be formed with a wide range of mechanical properties. Being self-extinguishing, PVC also has an inherent resistance to the flame. Plasticizers such as phthalates and adipates contribute to their flexibility. The feel of PVC is controlled by the amount of plasticizers and / or filler material, as well as the type of resin. Impact modifiers can be included to increase the resistance to rupture. Under UV radiation, and in the presence of oxygen and moisture, the PVC undergoes a process of dehydrochlorination and peroxidation very quickly with the formation of polyenes and subsequent cleavage and / or cross-linking of the chains. Additives that have UV stabilization effect can be included to prevent solar degradation. This stabilizer is titanium dioxide (Ti02) that provides adequate protection for most purposes and is introduced more frequently at levels up to 10 to 12 phr. At these levels, Ti02 can improve the weathering properties of the products of some degree of UV radiation that falls on the polymer. Ti02 is widely used in white and clear formulations. Ti02 is approximately 50% more expensive than unplasticized PVC used for outdoor service and PVC producers are looking for ways to reduce their consumption of Ti02. Thermoplastic, polymeric materials, streams are generally eliminated by incineration. They can also be removed by recirculation that can be achieved by increasing their oxidation temperature. The increase in oxidation temperature can be achieved through the use of additives. These additives have been known in general because they have certain different disadvantages as when these materials must be incinerated, these additives generate toxic fumes that need an additional treatment step that increases the total cost of the elimination. In any case, with PVC, the additional treatment for effluent gases is necessary.

Certain thermoplastic, polymeric materials can be either photodegradable or biodegradable. In general, the photodegradable polymeric thermoplastic materials are obtained by introducing photoactive additives into a base material such as, for example, polyolefin. These additives consist of molecules that contain oxygen and / or heavy metals that play a role in the initiation and formulation of free radicals under the action of ultraviolet (UV) radiation. Free radicals cause a breakdown of the polymer chains and therefore make the polymer fragile and mechanically degradable. Although frequently in use, these photoactive additives are generally strongly oxidized which can cause the degradation of the plastic material to start immediately after the material is manufactured, thereby reducing the shelf life of the thermoplastic, polymeric materials. In general, plastic, biodegradable materials can be obtained by the introduction of a biopolymer such as starch. Since the starch can be attacked by microorganisms, the material becomes susceptible to degradation. However, the incorporation of starch in this material may have disadvantages in that It can be partially decomposed during processing and is highly sensitive to water. In addition, starch is compatible with most polymers, and its incorporation during polymer manufacturing can return to the brittle final product. Additionally, in polymer films with a particularly small thickness, the particle size of the starch can be a limiting factor in the total manufacturing process and the cost becomes prohibitive. A number of biopolymers can also be used in addition to starch, such as, for example, other carbohydrates with a major disadvantage than in mixing with the polymeric material, the biopolymer may undergo various alterations such as oxidation and polycondensation. This alteration to the biopolymer can have a negative effect on the mechanical properties of the polymeric materials. As an alternative to the above, a biopolymer such as organosol lignin can be incorporated with the polymeric, thermoplastic materials.

BRIEF DESCRIPTION OF THE INVENTION This invention provides degradable polymers and polymer products having an organosol lignin incorporated therein. The incorporation of lignin improves the mechanical properties of the polymers while making them degradable under certain conditions. The polymers of this invention can be removed without incineration or recirculation, resulting in energy savings and minimal contamination.

DESCRIPTION OF THE PREFERRED MODALITIES The biopolymer used in this invention is a lignin that is separated from the biomass of the plant by a new chemical delignification technology based on organic solvents, for example ethanol. Generally referred to as organosol lignin, it is a fluid, non-toxic powder. It is soluble in aqueous alkalis and in selected organic solvents. In general, it is characterized by its hydrophobicity, purity, melt flow properties and a low level of carbohydrates and inorganic contaminants.

The lignins of this invention can be incorporated into various polymeric materials and can have various effects on the polymer mixture such as for example they can function as an antioxidant, a stabilizer against ultraviolet radiation and can improve the mechanical properties of these materials. The lignins of this invention can stimulate the degradation of polymeric materials when additives are added to the mixture. The products can be degraded by the photodegradation of polymeric materials and lignin or alternatively by the biodegradation of lignin under fertilizer conditions. The lignins of this invention can be mixed and combined with polymers such as for example polyethylene, polypropylene, polyvinyl chloride and polystyrene copolymers in a weight ratio of from about 0.5% to about 40% with the polymer of choice. The blends can then be processed by extrusion, calendering, injection or processes known in the art to produce articles of manufacture having different uses such as, for example, film and molded products. Alternatively, the lignin can be mixed with a copolymer such as, for example, acetate of ethylene (vinyl) or styrene-butadiene copolymers. The resulting mixture is a masterbatch that can be diluted by further mixing with polymers such as, for example, polyethylene, polypropylene, polyvinyl chloride, and polystyrene copolymers. The mixtures can be processed using methods known in the art to produce the desired final products. In a preferred embodiment, a main batch can be prepared by mixing with the organosol lignin from 35% to about 85% on a base by weight with the polymer of choice such as EVA, SBS or any other polymer known to have a glass transition temperature in the same interval as that of lignin. The main batch can be prepared by mixing all the ingredients in a direct way or in successive stages. For specific applications, the main batch can also be coextruded with a polymer of choice depending on the desired final product. Pellets can be produced with a core and a shell with a variable composition. The core of the pellet may have the main batch composition, while the shell may have the polymer composition of the proposed final product.

The pellets can be obtained in general by granulating the filaments leaving the extruder. The core of the pellet can be manufactured by considering the nature of the biopolymer that will be incorporated in it. When the organosol lignin is used, the pellet can be manufactured without causing any chemical or physical deterioration by mixing lignin or a major batch polymer of particular interest such as for example EVA or SBS or any other polymer of the main batch that is known to have a glass transition temperature in the same range as that of lignin. The core comprising from about 35% to about 85% lignin and 65% to 15% polymer of the main batch can be extruded at a temperature from about 115 ° C to about 145 ° C to form a polymer shell having a similar composition as the final product. It is believed that extrusion at the above temperature will not result in damage to lignin. The extrusion of the wrapper generally requires a temperature from about 170 ° to about 230 ° C. As an objective, the total composition of the extruded compound is preferably equivalent to the composition of the finished product. The thickness of the envelope can be adjusted according to the diameter of the core corresponding to the diameter of the central filament such that the level of lignin in the co-extruded end product is from about 0.5% to about 40%. In a preferred embodiment, for a core diameter of from about 1mm to about 2mm, the thickness of the wrapper is from about 4mm to about 5mm such that each individual pellet of the composite comprises from about 4% to about 25% of lignin An advantage of using coextrusion in the combination temperature of polyethylenes and polypropylenes is that the problem associated with thermal decomposition and oxidation of the biopolymer is mitigated. In this particular case, the compound coextruded in the extrusion, takes the appearance of pellets that are heterogeneous under the microscope but are still more homogeneous completely in contrast to the appearance of the pellets that result from the mechanical mixing of two different pellet compositions. The main batch of this invention can be processed by extrusion, blowing, injection or other processes known in the art. The machinery used in general requires adaptation to the processes of this invention to meet the shortest residence times required at critical temperatures such as, for example, the oxidation temperature. It is also believed that the processes of the invention can be operated at a lower temperature mainly due to the additional heat protection of the envelope to the lignin-rich core which is easier to melt and the viscosity of which is not so sensitive to the temperature like PE or PP. In certain specific applications of this invention, the organosol lignin powder with an average particle size of from about 0.1 microns to about 100 microns and an amount from about 0.5% to about 40% can be mixed with polyethylene or more generally a ethylene copolymer for manufacturing homogeneous films having a thickness from about 5 microns to about 100 microns. Polyethylene blends can be prepared by mixing directly or by using a master batch preparation. It has been observed that the resulting films can be degraded when iron stearate or any of the other photoactive additives are added and / or oxidizers such as salt of serious, in a range dependent on the shelf life of the target film and the conditions under which the film will be used. A preferred range is from about 0.1% to about 0.5% of the salt based on the total weight of the polymer blend. The plastic films obtained in this way can be used for many agricultural applications, as well as for the manufacture of plastic bags for waste, straws, etc. In agricultural applications, in which the stiffness of the film is essential, the polyethylene film containing lignin, of the present invention, is of no particular interest for use since the degradation of the film over time is total, both for the surfaces that are outside the earth as well as those that are buried inside the earth. Additionally, in the field of agricultural applications, the adsorption and absorption capacities of lignin, essential oils, insecticides and the like, will then allow a use of lignin as an additive for the new fungicidal, rodenticidal or other properties. Likewise, the adsorption properties of lignin can be used so that lignin can be incorporated into the photoactive products before its mixing with the copolymers, which has the advantage of increasing the homogeneity and the degradability of the film. On the other hand, this plastic film containing lignin can be coextruded, and therefore can be part of a composite film. It should be further noted that the initial mechanical properties of the lignin-containing degradable film of the present invention are comparable to those of a film that does not contain any lignin. Dependent in general and highly of the preparation processes, lignin behaves thermally by partially condensing with apparent melting and without oxidation in a temperature range from about 125 ° C to about 200 ° C and on the other hand by oxidation without condensation at about 160 ° C. The properties of lignin are suitable for the processes of this invention. When lignin is condensed, it is believed that it is capable of generating water at about from about 1% to about 6% of its weight. Therefore, special attention must be given to eliminate the water produced during the manufacture of the thermoplastic, polymeric material.

The lignin and the polymer can be mixed in an extruder which can be either single or double screw. The mixing is preferably carried out in a ventilated extruder such that any water vapor formed from the lignin is removed. The extrusion conditions are dependent on the scale of the process. The rotation speed of the screw is an important parameter and is a function of the materials introduced upstream. The temperature profile is also an important element of the success of a good mixture, since lignin must be protected from oxidation and thermal degradation. This can be achieved by adding the lignin to the already melted polymer or by using the main batch described herein. In mixing with lignin, lignin behaves as a thermal antioxidant which results in an increase in the oxidation temperature of the polymer. An increase in the oxidation temperature of the mixture allows the recirculation of this material, thus allowing it to melt again for reuse, without degradation. In the case where the material can not be recycled any longer and it may be necessary to incinerate the material effectively, the addition of lignin is beneficial since the heating value of lignin is equivalent to that of the polymer used, thus allowing its destruction by incineration. For example, when the polymer used is pure polyethylene, its oxidation temperature is from about 150 ° C to about 160 ° C. In contrast to about 10% lignin, the oxidation temperature is from about 185 ° C to 195 ° C and with about 25% lignin, the oxidation temperature is from about 195 ° C to about 205 ° C. In another example, when the polymer used is polypropylene, the oxidation temperature is from about 210 ° C to about 220 ° C. In contrast to about 10% lignin, the oxidation temperature is from about 255 ° C to about 265 ° C. The thermoplastic polymeric material of this invention can be used in applications known in the art, for example, in extrusion / blow molding applications, calendering, injection molding to form films, plates, sheets, tubes, bottle tops, roll paper, car parts and the like.

In order to improve the machining of the polymeric, thermoplastic materials of this invention, plasticizers such as styrene-butadiene rubber, zinc stearate, soybean oil to name a few may be added during manufacture. In general, since the polymeric, thermoplastic materials can not be perfumed, the invention provides for the addition of perfume material due to the presence of lignin or any other biopolymer that can absorb these fragrance additives. In one embodiment of this invention, the lignin can be hot or cold mixed, either alone or in conjunction with the polymeric, thermoplastic material. In this embodiment, lignin can be treated by maceration in solvents containing essential oils before it is mixed with the polymeric materials. In another embodiment, a mixture of fragrances such as for example terpenes and citronella can be injected directly into one of the sections of the extruder during the manufacture of the mixture. It should be noted that unexpectedly for polymers such as polyethylene, the addition of a biopolymer such as lignin to a material polymeric can lead to an improvement in the resilience of the material to ultraviolet radiation. This is unexpected since no additive is added that would improve photodegradation resistance but rather lignin plays a role in the stabilization of the polymeric, thermoplastic material for ultraviolet radiation degradation as shown in Table 1. It should also be note that without lignin, an increase in the duration of exposure to ultraviolet radiation causes significant polymer fragmentation and a sudden and significant variation in the molecular weight of the polymer.

Table 1 Molecular Weight Exposure time to Polyethylene + 10% UV radiation (hours) Polyethylene Lignin 0 320,000 300,000 30 240,000 242,000 200 35,000 120,000 In a preferred embodiment of this invention, PVC can be mixed on a weight basis with from about 0.5 to about 40% of organosol lignin with a specific gravity of about 1.27 and an average particle size of about 0.1 microns to about 100 microns. The final PVC / lignin mixtures have stronger mechanical properties and can be degraded under the effect of light. PVC blends can be used in medical, food, fashion and home applications. The following discloses a particular embodiment for mixing PVC with organosol lignin. The PVC used is a commercially non-plasticized resin (Geon 85862 from BF Goodrich Technical Center, Avon Lake, Ohio, USA) as a high molecular weight suspension polymer (k = 67) and has the following formulation: PVC resin, 100 phr; stabilizer, 2 phr; processing aid, 1.5 phr; impact modifier, 6 phr; lubricants, 3.75 phr; Ti02, variable from 0 to 10 phr. With 10 phr of Ti02, the PVC resin has a specific gravity of about 1.48. The PVC mixtures were prepared with the composition set forth in Table 2.

Table 2 Mixing Lignin No. TiO 2 (%) Organosol (%) 1 9. 09 0 2 6. 81 2.27 3 4. 54 4.54 4 2. 27 6.82 5 0 0 6 0 4.54 7 0 6.82 8 0 9.09 9 0 13.63 10 0 18.18 The blends were prepared by melt blending in a Haake Rheomix 600 equipped with sliding knives at a temperature of about 195 ° C. The mixing time was about 8 minutes at a speed of the sliding knives of about 65 rpm. PVC was added first and the second lignin after 30 seconds. Several batches were prepared for each formulation and after melt mixing, the obtained mixtures were milled to a particle size from about 3 to approximately 5 mm. The sheets with a thickness of about 2 mm were compression molded at about 195 ° C. After cooling with air and under pressure, the sheets were cut with a cutting die in protruding specimens for mechanical testing. The mechanical properties, tensile strength and elongation at rupture were measured before and after 5 days and 20 days of artificial weathering and correlated with the properties of PVC controls. They were measured in accordance with ASTM D 638 using an Instron universal test machine. The weathering of the samples was carried out using the equipment known in the art such as a Q-Panel QUV. In this tester rain and spray were simulated by a condensation system and contains a series of UV-A lamps with a maximum emission at 343 nm and a spectral energy distribution from 295 to approximately 400 nm. All specimens were subjected to several cycles of 4 hours each of UV exposure at an equilibrium temperature from about 50 ° C alternating with exposure to condensation at an equilibrium temperature of about 40 ° C. He The number of days of accelerated decomposition to the weather was 5 and 20. Table 3 shows the influence of lignin on the melting characteristics of the same mixtures. The processability or melting characteristics of PVC blends is generally influenced by the type of resin and additives present. A change in the formulation especially in the case of a rigid PVC composition can affect the melting characteristics of the PVC blends and consequently their processability. Inappropriate processability can have a negative effect on the mechanical properties of PVC and its ability to decompose in the open. It has been found that The melting characteristics of PVC and lignin mixtures formulated with or without Ti02 present almost the same characteristics as PVC controls. It can be concluded that the melting characteristics of the lignin mixtures with PVC in comparison with the PVC controls are very close and the presence of lignin does not have a negative effect on the processability of the PVC and lignin mixtures. The specimens of the mixtures of PVC and lignin with Ti02 are colored beige to tan and the mixtures of lignin and PVC without Ti02 were dark brown.

Table 3 Type of Time Average Average Temperature Value Average Mix Torque of the Melt Melt (° C) (S) Max In the En At the (fusion) term of force term of 3 min. maximum 8 min. 1 75 2500 1575 184 205 2 80 2530 1600 180 204 3 85 2570 1600 183 204 4 88 2425 1475 182 204 5 165 1960 1430 182 204 6 100 2280 1430 186 204 7 105 2350 1420 189 203 8 78 2370 1400 181 202 Table 4 shows the stress-strain data for the PVC controls and the PVC and lignin mixtures before and after 5 and 20 days. The lack of correlation between the values of the tensile stress data predicted by the theoretical model developed by Nielsen (J. Appl. Polym, Sci., Vol. 10, 97-103 (1966)), particularly in the case of perfect adhesion between the filler (in this case lignin) and the polymer (in this case PVC) and the experimental values shown in Table 4 suggest a certain degree of interaction between the two polymers in the mixture. In addition, up to a certain level of approximately 6.81% lignin acts as a reinforcing agent without having a negative impact on the elongation. As can be seen after weathering, all mixtures show a higher tensile strength value than PVC controls, and the increased values can be correlated with the lignin load and the decomposition period in the open. . The decrease in the elongation at the break can also be correlated with the period of decomposition to the weather and the load of lignin. It can also be seen that after 20 days of the decomposition period in the open, all the mixtures despite their level of Ti02 show a high degree of embrittlement and an increase in tensile strength with an almost lack of elongation. It is believed that the observed effect may be due to recirculation.

Table 4 Type of Resistance to Rupture Elongation Traction Mix (MPA) (%) Initial 5 Days 20 Days Initial 5 Days 20 Days 42.30 48.36 50.52 280 289 47 1 40.15 45.76 49.73 332 292 269 2 43.85 48.30 49.86 281 193 61 3 44.14 49.40 50.58 326 110 45 4 47.05 50.41 51.60 312 91 30 8 48.66 50.26 51.67 182 51 29 In addition, after the decomposition period outdoors, mixtures of PVC without Ti02 and mixtures of PVC comprising lignin are characterized by a change in color observed only on the side exposed to UV light. In the case of PVC mixtures without Ti02, the color changed from white-gray to reddish-yellow and in the case of the PVC mixtures comprising lignin, the color changed to lighter shades. In the case of PVC mixtures comprising 9.09% Ti02, the change in color after weathering is barely perceptible, which is believed to be due to the effect of Ti02 on the weathering of PVC. It is believed that embrittlement and color change due to artificial decomposition to the weather shows the susceptibility of ambient polymers interacting with UV radiation. It is believed that lignin is photodegraded as a result of the formation of free radicals, mainly phenoxy radicals. The PVC blends of this invention can be formulated to achieve good weathering by mixing synergistic levels of Ti02 and lignin. The invention and many of its accompanying advantages will be understood from the foregoing description, and it will be apparent that various changes and modifications can be made without departing from the spirit and scope of the invention or sacrificing all its material advantages, the specific materials , methods and the example described hereinabove are mainly preferred embodiments, for example, by mixing different kinds of PVC compounds with lignin, other types of mixtures can be formulated which would have the advantage of a lower processing temperature and milder conditions of decomposition to the elements. Suitable UV absorbers and / or light-thermal stabilizer systems can also be included in the formulations to achieve the proper mechanical properties prior to weathering and suitable shades of colors in the final blend. In another example, lignin and Ti02 can be formulated together for. further optimize the photochemical reaction of lignin and Ti02, thus affecting the final photodegradability of the formulation. It is noted that with respect to this date, the best method known to the applicant to carry out the present invention is that which is clear from the description of the present invention. Having described the present invention as above, the content of the following is claimed as property:

Claims (15)

1. A method for manufacturing a degradable, polymeric thermoplastic blend, characterized in that it comprises the step of mixing a polymeric material with an organosol lignin in a weight ratio of from about 0.5 to about 40% on a weight basis with the polymeric material.

2. The method according to claim 1, characterized in that the polymeric material is selected from the group consisting of polyethylene, polypropylene, poly (vinyl chloride) and polystyrene copolymers.

3. A degradable thermoplastic film, characterized in that it comprises polyethylene and an organosol lignin in a weight ratio of from about 0.5 to 40% on a weight basis with the polyethylene.

4. The film according to claim 3, characterized in that it also comprises an oxidative additive in a weight ratio from about 0.1% to about 0.5% with the polymer blend.

5. The film according to claim 5, characterized in that the lignin has an average particle size from about 0.1 microns to about 100 microns.

6. The film according to claim 5, characterized in that it has a thickness from about 5 to about 100 microns.

7. A method for manufacturing a masterbatch, characterized in that it comprises the steps of mixing an organosol lignin with a polymeric material in a weight ratio of from about 35% to about 85% with the polymeric material.

8. The method according to claim 7, characterized in that the polymeric material is selected from the group consisting of ethylene (vinyl) acetate and styrene-butadiene copolymers.

9. A method for manufacturing a pellet, the method is characterized in that it comprises the steps of: mixing an organosol lignin with a first polymeric material in a weight ratio of from about 35% to about 85% with the first polymeric material to form a mixture of main lot; and coextruding the mixture of the main batch with a second polymeric material to form the pellet, the pellet has a core and a shell, the main batch forms the core and the second polymeric material forms the shell.

10. The method according to claim 9, characterized in that the pellet comprises from about 0.5% to about 40% of the organosol lignin in a base by weight with the first and second polymeric material.

11. The method according to claim 10, characterized in that the first polymeric material is selected from the group which consists of ethylene (vinyl) acetate and styrene-butadiene copolymers.

12. The method according to claim 11, characterized in that the second polymeric material is selected from the group consisting of polyethylene, polypropylene, poly (vinyl chloride) and polystyrene copolymers.

13. An article of manufacture, characterized in that it is in accordance with the method of claim 1.

14. A manufacturing article, characterized in that it is in accordance with the method of claim 7.

15. An article of manufacture, characterized in that it is in accordance with the method of claim 9.