BRPI0714690A2 - UV-resistant multilayer cell confinement system - Google Patents

Abstract

CELLULAR CONTAINMENT SYSTEM IN UV RESISTANT MULTILAYERS. The present exhibition refers generally to a polymeric cell confinement system that can be filled with soil, concrete, aggregate, earthy materials and others. More specifically, the present exhibition refers to a cell confinement system characterized by better durability against damage by YV light, humidity and aggressive soils, or their combinations.

Description

Report of the Invention Patent for "UV RESISTANT MULTI-LAYER CELLULAR CONFINEMENT SYSTEM".

REFERENCE TO RELATED ORDERS

This application relates to US Patent Application Serial No. (PRSI 200003), filed concurrently and entitled "Geotechnical Articles"; and US Patent Application Serial No. (PRSI 200004), filed concurrently and entitled "High Performance Geosynthetic Article"; U.S. Provisional Patent Application Serial No. (PRSI 200005), filed concurrently and entitled "Welding Process and Its Geosynthetic Products"; and U.S. Provisional Patent Application Serial No. (PRSI 200006), filed concurrently and entitled "Process for the Production of Compatible Polymeric Blends". All four of these patent applications are incorporated herein by reference in their entirety. GROUNDS

The present disclosure refers generally to a polymeric cell confinement system that can be filled with soil, concrete, aggregate, earth materials and others. More specifically, the present disclosure relates to a cell confinement system characterized by improved durability against damage generated by ultraviolet light, moisture, aggressive combinations.

Soil reinforcement plastics, particularly cell confinement systems (CCSs), are used to increase the load bearing capacity, stability and erosion resistance of geotechnical materials such as soil, rocks, sand, stones, peat, clay, concrete, aggregate. and earth materials that are supported by said CCSs.

CCSs comprise a plurality of high density polyethylene (HDPE) strips in a characteristic three-dimensional beehive structure. The strips are welded together at different locations to achieve this structure. Geotechnical materials can be reinforced and stabilized within or by CCSs. Geotechnical material that is stabilized and reinforced by said CCS is hereinafter referred to as reinforced geotechnical material (GRM). CCS surfaces can be embossed to increase friction with GRM and decrease relative movement between CCS and GRM.

CCS reinforces GRM by increasing its shear strength and stiffness as a result of the resistance of cell wall arcs, passive resistance of adjacent cells, and the friction between CCS and GRM. Under load, CCS generates powerful lateral confinement forces and ground-wall cell friction. These mechanisms create a point structure with high flexural strength and stiffness. Bridge action improves the long-term load-deformation performance of common granular filler materials and allows dramatic reductions of up to 50% in the thickness and weight of structural support elements. CCSs can be used in load-bearing applications such as road base stabilization, intermodal courtyards, under rail tracks to stabilize rail ballast, retaining walls, to protect GRM or vegetation, and on slopes and canals.

The term "HDPE" hereinafter refers to a polyethylene characterized by a density of more than 0.940 g / cm3. The term medium density polyethylene (MDPE) refers to a polyethylene characterized by a density of more than 0.925 g / cm3 to 0.940 g / cm3. The term low density linear polyethylene (LLDPE) refers to a polyethylene characterized by a density of 0.91 to 0.925 g / cm3.

The plastic walls of CCSs may be damaged during service and use in the field by UV light, heat and humidity (UHH). Damage results in brittleness, less flexibility, toughness, impact and puncture resistance, poor tear resistance and discoloration. In particular, thermal damage to CCS is significant in hot areas of the globe. As used herein, the term "warm areas" refers to areas located up to 42 degrees latitude on both sides of the equator and particularly along the desert belt. Hot areas include, for example, North Africa, Southern Spain, the Middle East, Arizona, Texas, Louisiana, Florida, Central America, Brazil, most of India, South China, Australia, and part of Japan. Hot Areas they regularly experience temperatures above 35 ° C and intense sunlight for periods of up to 14 hours each day. Dark plastic surfaces exposed to direct sunlight can reach temperatures as high as + 90 ° C.

Some strategies have been applied industrially to protect

Manage the plastic walls against such damage by treating the polymer that makes up the plastic walls. For dark colored products, eg black or dark gray products, carbon black can be introduced to block UV light and dissipate free radicals. However, a disadvantage produced by the use of carbon black is its aesthetic appearance. Black CCSs are less attractive in applications where CCS is part of a landscape structure. A second disadvantage is that black CCSs tend to absorb sunlight and heat up. HDPE and MDPE tend to flow when heated above 40 - 50eC. As a result, creep can be severely accelerated, particularly at welding points and thinner wall structures, potentially resulting in structural failures.

CCSs are usually immobilized or anchored to the GRM by wedges, tendons, bars or anchors. This immobilization is particularly crucial when CCS is used to reinforce a slope. Wedges, tendons, bars or anchors are usually made of iron and can be heated by direct sunlight to temperatures that can exceed 60 - 85 sC. The high conductivity of the iron also transmits heat to the buried part of the CCS. These anchor points are subject to severe stress concentrations. Without UHH protection, these anchor points can fail before any significant damage is observed on the rest of the CCS.

Voltage is also generated in the welds between the strips that make up the CCS. Tension can be applied by compression when humans walk over the CCS during installation, before and while it is filled with GRM, or when GRM is dumped into the CCS to fill the cells. GRM can also expand when it gets wet or when water already present in GRM freezes in cold weather. In addition, GRM has a thermal expansion coefficient (CTE) about 5-10 times less than the HDPE used to prepare the strips. Thus, HDPE will expand much more than GRM; This causes stress along the walls of the CCS and particularly in welds.

Some CCSs are pigmented in GRM-like hues they sustain. These include light-colored products and custom-tinted CCSs such as ground-colored CCSs, grass-colored CCSs, and peat-colored CCSs.

For CCSs, special additives (ie, in addition to carbon black) are required to maintain their properties for periods of 20 years or more. The most effective additives are UV absorbers such as benzotriolols and benzophenones, radical scavengers such as blocked amine light stabilizers (HALS), and antioxidants. Typically, "packets" of more than one additive are supplied to the polymer. Additives are introduced into the polymer usually as a master blend or holko blend, a dispersion and / or solution of the additives in a polymeric carrier or waxy carrier.

The amount of additives in the polymer used to prepare the CCS depends on the shelf life required for the CCS. To provide protection for periods of about 5 years, the amount of additives required is lower than if protection is required for a period of 10 years or more. As polymer additives leach, evaporate or hydrolyze over time, the actual amount of additives required for protection over a long time period is about 2 to 10 times greater than the amount needed for short term protection needs. In other words, the amount of additives added to the polymer must compensate for leaching, evaporation and hydrolysis and is therefore significantly greater than the amount required for short term protection. In addition, as the heat and humidity where CCS is to be used increases, more additives need to be added to the polymer to maintain its level of protection. Additives are generally dispersed or otherwise dissolved.

fairly evenly throughout the cross section of the polymeric strips used to prepare the CCS. However, most of the interaction between additives and UHH-damaging agents occurs in the outermost volume, that is, 10 to 200 microns, of the polymeric strip or film.

Some warm areas, particularly tropical areas, also experience high humidity and heavy rainfall. The combination of high humidity and heat accelerates the hydrolysis, extraction and evaporation of protective additives from the polymeric strip. Most significant is the loss of UV absorbers, such as benzophenones and benzotriazoles, and thermal stabilizers - particularly blocked amine light stabilizers (HALS). Once these additives are lost, the polymeric strip is easily attacked and its properties deteriorate rapidly.

U.S. Patent No. 6,953,828 discloses a membrane, including a geomembrane, stabilized against UV. The patent relates to very low density polypropylene and polyethylene compositions which are effective as membranes but are not practical for CCSs. Polypropylene is too fragile at temperatures below freezing. Very low density polyethylene is too weak for use in a CCS because it tends to flow under moderate loads. Once a CCS flows, the integrity of the CCS and GRM is disrupted, and structural performance is irreversibly damaged. In addition, polypropylene requires a large additive load to overcome leaching and hydrolysis; This results in an uneconomical polymer.

U.S. Patent No. 6,872,460 teaches a bilayer polyester film structure wherein UV absorbers and stabilizers are introduced in one or two layers. Several types of polyester are generally applicable to geo-grids, which are two-dimensional articles used to reinforce soils, such as a reinforcement tendon matrix. Geo-grids are usually buried underground and therefore are not exposed to UV light. In contrast, CCSs are three-dimensional and are usually partially exposed above ground level, thus exposed to UV light. Polyesters are generally unsuitable for CCSs due to their rigidity, poor impact resistance and perforation at room temperature and particularly below freezing, medium to poor hydrolytic resistance (particularly when in direct contact with basic media such as concrete and calcined soils). ) and its overall cost. Similarly, polyesters require a large additive load to overcome leaching and hydrolysis; This results in an uneconomical polymer.

For thin polymeric strips (characterized by a thickness of

less than about 500 microns), the actual amount of additive generally required corresponds to the calculated theoretical required amount. In thicker strips (characterized by a thickness of more than about 750 microns - this is usually the case for structural geotechnical reinforcement elements - CCS, for example), however, the actual total amount of additive required is generally much larger than calculated theoretical quantity required. For high performance CCSs with thicknesses of about 1.5 mm or more where strength, toughness, flexibility, tear and puncture resistance and low temperature retention are required, the total amount of additive required is usually 5 to 10 times. greater than the calculated theoretical required quantity. UHH protection additives are very expensive in relation to polymer cost. Most manufacturers therefore provide additives for loads that most closely correspond to the calculated low (ie minimum) theoretical load level, not the higher loads required for long term protection over periods of 50 years or more. In addition, HDPE and MDPE provide poor barrier properties against ingress of harmful ions and molecules into the polymer, and against leaching and evaporation of polymer additives. Because of this, in reality, most manufacturers currently do not guarantee the long-term durability of their thick polymeric strips. Current CCSs use HALS and UV absorbers in the amount of 0.1 to 0.25 weight percent dispersed throughout the polymeric strip.

Another aspect related to durability in outdoor environments is the type of polymer used for CCS. Selecting the right polymer for this application is a balance between economy, ie cost of raw materials, and long term durability. In this regard, polyethylene (PE) is one of the most popular materials to use because of its cost balance, strength, flexibility at temperatures as low as 609C and ease of processing on standard extrusion equipment. In addition, polyethylene is moderately resistant to UV light and heat. However, without additives, polyethylene is susceptible to degradation within one year to a degree that is unacceptable for commercial use. Even when highly stabilized, PE is still inferior to more UV resistant polymers such as ethylene acrylic ester copolymers and terpolymers.

On the other hand, polymers which exhibit higher UV and heat resistance, such as acrylic and methacrylic ester copolymers and terpolymers and particularly ethylene-acrylic ester copolymers and terpolymers, are very suitable for commercial application from the strength point of view. the UHH. However, its relatively high cost and relatively low module characteristics and resistance limit its large-scale use in CCS applications.

There is a need for a cost effective UHH resistant polymeric strip and CCSs comprising it, particularly GRM-type light colored strips and their CCSs. These CCSs are resistant to harsh conditions, particularly outdoor applications, in climates ranging from arid, tropical and subtropical to arctic, and have a service life of 50 years or more. BRIEF DESCRIPTION

This exhibition refers to a geotechnical article, particularly a cell confinement system (CCS), which exhibits high durability against UV light, heat and humidity for periods of at least 2 years. In specific embodiments, CCS exhibits this durability for at least 10 years. In additional specific embodiments, CCS exhibits this durability for at least 20 years and up to 100 years. Durability means lack of bleaching or cracking and retention of original color, surface integrity, strength, modulus, elongation at break, puncture resistance, creep resistance and weld strength.

In an exemplary embodiment, the CCS comprises a plurality of polymeric strips. Each polymeric strip comprises at least one inner polymeric layer and at least one outer polymeric layer. At least one outer polymer layer is more resistant to UV light, moisture, or heat (UHH) than at least one inner polymer layer. Each polymeric layer comprises at least one type of polymer. The at least one outer polymeric layer also comprises a UV absorber or a blocked amine light stabilizer (HALS). The UV absorber blocks and prevents harmful UV light from penetrating at least one inner polymeric layer. HALS deactivates harmful radicals generated in the outer layer (s) of diffusion to the inner layer (s) of the polymeric strip.

In further embodiments, a polymeric layer comprises an additive selected from the group consisting of antioxidants, pigments and dyes.

In other embodiments, at least one polymeric layer may comprise a filler. In specific embodiments, the charge has a higher thermal conductivity than the polymeric layer polymer.

In still other embodiments, at least one layer of the polymeric strip comprises a pigment or dye. Preferably, the layer has a color similar to GRM that is supported by CCS. Preferably, the color is not black or dark gray.

CCS can be used to enforce a GRM.

Other CCSs and devices are also featured. Methods of preparing and using the polymeric strip and / or CCS are also presented. These and other embodiments are described in more detail below. DESCRIPTION OF DRAWINGS

The following is a brief description of the drawings, which are presented for purposes of illustration of the exemplary embodiments set forth herein and not for purposes of limitation thereof.

FIGURE 1 is a perspective view of a layer CCS.

only.

FIGURE 2 is a perspective view of a cell containing a reinforced geotechnical material (GRM). FIGURE 3 is a perspective view of a cell containing a GRM and a wedge.

FIGURE 4 is a perspective view of a cell containing

a tendon.

FIGURE 5 is a perspective view of a cell containing

a tendon and latches.

FIGURE 6 is a perspective view of an exemplary embodiment of a cell including a reinforced wall portion.

FIGURE 7 is a view of an exemplary polymeric strip used in the CCS of the present disclosure. DETAILED DESCRIPTION

The following detailed description is provided to enable those skilled in the art to prepare and use the embodiments set forth herein and provides the best modes considered for performing these embodiments. Several modifications, however, will be clear to those skilled in the art and should be considered to be within the scope of this disclosure.

A more complete understanding of the components, processes and apparatus disclosed herein can be obtained with reference to the attached drawings. These figures are only schematic representations based on the convenience and demonstrability of the present disclosure and, therefore, are not intended to indicate relative size and dimensions of the devices or their components and / or to define or limit the scope of exemplary embodiments.

This exhibition refers to a containment system.

(CCS) comprising a plurality of long-term, high-durability polymeric strips for use in outdoor applications. Each strip comprises at least one outer polymeric layer and at least one inner polymeric layer. The outer polymeric layer is more resistant to UHH than the inner polymeric layer. In particular, the outer polymeric layer is more resistant to UV light, moisture or heat (UHH) than virgin HDPE. The term "virgin HDPE" refers to any HDPE received from a reactor before being mixed with any UV or HALS absorbing additives. It should be noted that any polymer in a reactor generally contains 200 - 1,000 ppm antioxidant.

FIGURE 1 is a perspective view of a single layer CCS. The CCS 10 comprises a plurality of polymeric strips 14. Adjacent strips are joined together by separate physical joints 16. The attachment may be by gluing, stitching or welding, but is generally by welding. The portion of each strip between two joints 16 forms a cell wall 18 of an individual cell 20. Each cell 20 has cell walls made of two different polymeric strips. The strips 14 are linked together to form a beehive pattern with the plurality of strips. For example, outer strip 22 and inner strip 24 are joined together by physical joints 16 which are regularly spaced along the length of strips 22 and 24. A pair of inner strips 24 are joined together by physical joints 32. Each As a result, when the plurality of strips 14 are stretched in a direction perpendicular to the faces of the strips, the strips bend sinusoidally to form the CCS 10. At the edge of the CCS, where the ends of the two polymeric strips 22 and 24 meet, an end weld 26 (also considered a joint) is made a short distance from the end 28 to form a short tail 30 which stabilizes the two polymeric strips 22 and 24.

The CCS 10 can be reinforced and grounded in at least two different ways. Openings 34 may be formed in the polymeric strips so that the openings share a common axis. A tendon 12 can then be extended through the openings 34. The tendon 12 strengthens the CCS 10 and improves its stability by acting as a continuous integrated anchor element that prevents unwanted displacement of the CCS 10. The tendons They may be used in channel and slope applications to provide additional stability against gravitational and hydrodynamic forces and may be required when a naturally hard bottom or soil / rock layer prevents the use of shells. A wedge 36 can also be used to anchor CCS 10 to the substrate to which it is applied, for example, to the floor. The wedge 36 is inserted into a substrate deep enough to provide an anchor. Wedge 36 may have any shape known in the art (that is, the term "wedge" refers to function but not shape). Tendon 12 and wedge 36, as shown, are simply a section of iron or steel bar cut to an appropriate length. They may also be formed of a polymeric material. They can be formed with the same composition as CCS itself. It may also be useful if tendon 12 and / or wedge 36 has a greater stiffness than CCS 10. A sufficient number of tendons 12 and / or wedges 36 is used to reinforce / stabilize CCS 10. It is important to note that tendons and / or cuffs should always be placed against the cell wall, not against welding. Tendons and / or wedges have high loads concentrated in a small area and, as welds are relatively weak points in the CCS, placing a tendon or wedge against a weld increases the likelihood that the weld will fail.

Additional apertures 34 may also be included in the polymeric strips as described in U.S. Patent No. 6,296,924. These additional openings increase GRM friction locking by up to 30%, increase root entanglement of plant systems as roots grow between cells 20, improve lateral drainage through strips for better performance in saturating soils. and promote a healthy soil environment. Reduced installation and long-term maintenance costs may also occur. In addition, these CCSs are lighter and easier to handle compared to solid walled CCSs.

FIGURE 2 is a perspective view of a single cell 20 containing a reinforced geotechnical material (GRM). Cell 20 is represented as it would appear when the CCS was located on a slope (indicated by arrow A), so that the GRM trapped within cell 20 has settled substantially horizontally (i.e., flat relative to the surface of the earth), while the cell walls 14 of the CCS 10 are substantially perpendicular to the declilve A on which the CCS is located. Because cell walls 14 are not aligned horizontally with the GRM, the GRM rests substantially on the lower cell wall on the slope, and an "empty area" is left on the highest cell wall on the slope.

Cell walls 14 are subjected to forces F1 and F2.

As a result of the slope, the force F1 (exerted by the weight of the GRM) and the force F2 (exerted by the empty area of a cell further down the adjacent slope) are not balanced. Force F1 is greater than force F2. This unbalanced force tensions the joints 16. In addition, the GRM also exerts a separation force F3 against the joints 16. This separation force results from the GRM mass and natural forces. For example, GRM will expand during wet periods when retaining water. The GRM will also expand and contract, for example, through repeated freeze-thaw cycles of water trapped inside cell 20. This shows the importance of a strong weld in each joint 16.

FIGURE 3 is a perspective view of a single cell 20 containing a reinforced geotechnical material (GRM) and a wedge 36. The wedge 36 applies an additional force F4 to the upper cell wall on the slope to help balance the forces on the cell walls 14. Additional force is applied to a localized part of the cell wall higher up the slope and can be detrimental to the cell wall if not strong enough and creep resistant.

FIGURES 4 and 5 are perspective views of a single cell 20 containing a tendon 12. As described above, the tendon 12 extends through the openings 34 in the strips 14 and is used to stabilize the CCS 10, particularly in those. situations where wedges cannot be used 36. Tension is also located on strips 14 around openings 34. For example, tendon 12 may have a different CTE than strips 14. In applications where strips 14 are provided with openings 34, but no tendon 12 is used, GRM or water / ice can also seep into opening 34; expansion then increases tension and may damage the integrity of strip 14. As shown in FIGURE 5, locks 38 may be used to distribute tension over a larger area, but tension still exists. Using a lock 38 provides additional protection against long-term failures.

FIGURE 6 is a perspective view of an exemplary embodiment of a cell including a reinforced wall portion. A wedge 36 is located within cell 20. As discussed with reference to FIGURE 3, wedge 36 applies additional force to a localized portion of the cell wall higher up the slope and may be detrimental to the cell wall. if not strong enough and creep resistant. In an exemplary embodiment of the present disclosure, a reinforced wall portion 40 with a width greater than that of the wedge 36 is installed between the wedge 36 and the upper cell wall on the slope. Like the lock 38, the reinforced wall portion 40 distributes the tension over a larger area of the cell wall. In one embodiment, the reinforced wall portion 40 extends beyond the top edge of the wall and folds down over the distal side of the wall, further increasing the resistance of the overall wedge contact portion of the wall. In other embodiments, the reinforced wall portion 40 may also have an opening 34 to accommodate the use of a tendon 12.

In one embodiment, the reinforced wall portion 40 is fixed to the wall with a suitable adhesive, for example a pressure sensitive adhesive or a curable adhesive. In another embodiment, the reinforced wall portion 40 may be fixed to the wall by welding, particularly ultrasonic welding, or stitching, performed on site. The reinforced wall portion 40 may be made of any suitable material. In particular embodiments, it is made of the same material as the cell wall. If desired, the reinforced wall portion 40 may also be stiffer than the wall to withstand more of the tension itself.

FIGURE 7 is a view of an exemplary polymeric strip used in the CCS of the present disclosure. The polymeric strip 200 comprises at least one outer polymeric layer 210 and at least one inner polymeric layer 220. Here, a polymeric strip with two outer polymeric layers 210 is shown. It is dispersed in at least one outer polymeric layer. 210 a UV absorber 230 or a blocked amine light stabilizer 240.

The at least one outer polymeric layer of the polymeric strip comprises a UV absorber or a blocked amine light stabilizer (HALS). The UV absorber may be an organic UV absorber, such as a benzotriazole UV absorber or benzophenone UV absorber. The UV absorber can also be an inorganic UV absorber. The at least one outer polymeric layer may comprise additional additives. The additive is selected from the group consisting of thermal stabilizers, antioxidants, pigments, dyes and carbon black.

The polymeric strip may comprise more than one outer polymeric layer. In a specific embodiment, the polymeric strip comprises a first outer polymeric layer and a second outer polymeric layer. The inner polymeric layer (s) are between the first outer polymeric layer and the second outer polymeric layer. Each outer polymeric layer comprises a greater number of additives than the inner polymeric layer (s). In other embodiments, the polymeric strip comprises a first outer polymeric layer and a second outer polymeric layer. One outer polymeric layer comprises a higher total concentration of UV absorbers and HALS additives than the other outer polymeric layer.

In other embodiments, the polymeric strip is a layered strip.

only.

The additive content in the outer polymer layer (s) is sufficient.

to provide protection to the polymeric strip for a period of 2 to about 100 years. The term "about" hereinafter refers to a value 20% less than or greater than the given value modified by the term "about". In specific embodiments, the amount of additives gives sufficient protection to the polymeric strip for a period of at least 2 years. At additional times, the amount of additives gives sufficient protection to the polymeric strip over a period of at least 5 years. In additional specific embodiments, the amount of additives provides sufficient protection to the polymeric strip for at least 20 years and up to 50 years, regardless of weather conditions such as humidity, temperature and intensity of UV light. The term "sufficient protection" refers to the ability of the polymeric strip to retain both (i) its color and shade; (ii) its mechanical characteristics over a period of 2 to 100 years with at least 50% of the original color, color tone or mechanical characteristics of the polymeric strip. Preferably, the polymeric strip retains at least 80% of its original color, color tone or mechanical characteristics. The outer polymeric layer (s) comprises

UV sorbent. In particular embodiments, the UV absorber is organic and is a commercially available benzotriazole or benzophenone such as Tinuvin ™ manufactured by Ciba and Cyasorb ™ manufactured by Cytec. The outer polymeric layer (s) may also comprise a blocked amine light stabilizer (HALS) alone or with the UV absorber. HALS are molecules that provide long term protection against free radicals and light-initiated degradation. In particular, HALS do not contain phenolic groups. Its limiting factor is the rate at which they leach or are hydrolyzed. The organic UV absorber and HALS together are present in the amount of from about 0.01 to about 2.5 weight percent, based on the total weight of the layer.

The outer polymeric layer (s) may also comprise an inorganic UV absorber. In particular embodiments, the UV absorber is in the form of solid particles. Solid particles are characterized by negligible polymer and water solubility and negligible volatility and therefore do not tend to migrate out or be extracted from the layer (s). The particles may be microparticles (for example from about 1 to about 50 micrometers in average diameter), submetric particles (for example from about 100 to about 1000 nanometers of average diameter) or nanoparticles (for example , from about 5 to about 100 nanometers in average diameter). In specific embodiments, the UV absorber comprises UV-adsorbing solid inorganic nanoparticles. Unlike organic UV absorbers, which are polymer soluble and have mobility even at high molecular weights, inorganic UV absorbers have virtually no mobility and are therefore very resistant against leaching and / or evaporation. Solid UV-absorbing nanoparticles are also transparent in the disible spectrum and are distributed very evenly. Consequently, they provide protection without any contribution to the color or shade of the polymer. Solid particles are also very insoluble in water, improving the durability of the polymer. In particular embodiments, UV absorbing nanoparticles comprising a material selected from the group consisting of titanium salts, titanium oxides, zinc oxides, zinc halides and zinc salts. In particular embodiments, the UV absorbing nanoparticles are titanium dioxide. Examples of commercially available UV absorbing particles are SACHTLEBEN ™ Hombitec RM 130F TN from Sachtleben, Zinc Oxide ZANO ™ from Umicore, Zano Oxide NanoZ ™ from Advanced Nanotechnology Limited and AdNano Zinc Oxide ™ from Degussa. UV absorbing particles may be present in a charge of from about 0.01 to about 85 weight percent, by weight of the polymeric layer. In more specific embodiments, inorganic UV-absorbing particles have a charge of from about 0.1 to about 50 weight percent, based on the total weight of the polymeric layer. In a specific embodiment, the polymeric layer comprises an inorganic UV absorber, HALS and an optional organic UV absorber.

In some specific embodiments, the inner polymer layer (s) do not contain any organic UV absorber, inorganic UV absorber or HALS additives. In other specific embodiments, the inner polymeric layer (s) may comprise organic UV absorbers and HALS together in an amount of from 0 to about 0.5. weight percent based on the total weight of the layer. The inner polymeric layer (s) may also comprise inorganic UV absorbers in an amount from 0 to about 0.5 weight percent based on the total weight of the layer. Any layer may also comprise an antioxidant. Specific antioxidants that may be used include blocked phenols, phosphites, phosphates and aromatic amines.

Any layer may also comprise a pigment or dye. Any suitable pigment or dye may be used that does not significantly adversely affect the desired properties of the overall polymeric strip. In specific embodiments, at least one layer of the polymeric strip (generally an outer polymeric layer) is colored to have approximately the color of the GRM supported by the polymeric strip. In general, the color is different from black or dark gray, particularly any color that is not in the gray scale. The colored polymeric layer need not have a uniform color; Color patterns (such as camouflage) are also considered. In specific embodiments, the polymeric strip may have a vivid color, such as red, yellow, green, blue or mixtures thereof, and mixtures thereof with white or black, as described by the CIELAB color coordinates. A preferred group of colors and shades are brown (like soil), yellow (like sand), brown and gray (like peat), whitish (like aggregate), light gray (like concrete), green (like grass) ) and a multicolored appearance that is stained, marked, grainy, dotted or marble-like. These colors have the utilitarian feature of allowing CCS to be used in applications where CCS is visible (ie not buried or covered with filler material). For example, CCS can be used on terraces where the outer layers are visible, but it can be colored to blend in with the environment. In further particular embodiments, the polymeric strip contains a pigment or dye, but does not contain smoke blacks. In general, for the purposes of this application, carbon black is considered to be a UV absorber rather than a pigment.

A polymeric layer may also comprise a filler. The polymeric layer may comprise from about 1 to about 70 weight percent filler, based on the total weight of the polymeric layer. In additional embodiments, the polymeric layer comprises from about 10 to about 50 weight percent filler or from about 20 to about 40 weight percent filler, based on the total weight of the polymeric layer.

The filler may be in the form of fibers, particles, flakes or yarns. The charge may have an average particle size of less than about 50 microns. In additional embodiments, the filler has an average particle size of less than about 30 microns. In additional embodiments, the charge has an average particle size of less than about 10 microns.

Various materials can serve as cargo. In some embodiments, the filler is selected from the group consisting of metal oxides, metal carbonates, metal sulfates, metal phosphates, metal silates, metal borates, metal hydroxides, silica, silicate, aluminate, alumosilicate, fiber, yarn, industrial ash, concrete or kimide powder and natural fibers such as kenaf, hemp, flax, ramie, sisal, newprint fibers, paper mill sludge, sawdust, wood flour, carbon, aramid, or mixtures thereof.

In additional specific embodiments, the filler is a mineral selected from the group consisting of calcium carbonate, barium sulphate, dolomite, alumina trihydrate, talc, bentonite, kaolin, wollastonite, clay and mixtures.

The filler can also be surface treated to increase compatibility with the polymer used in the polymeric layer. In specific embodiments, the surface treatment comprises a sizing agent or coupling agent selected from the group consisting of fatty acids, esters, amides and their salts, polymer or oligomer containing silicone and organometallic compounds such as titanates, silanes and zirconates. .

In additional specific embodiments, the filler has a higher thermal conductivity than that of the polymeric layer polymer. In general, in polymeric layers that have poor thermal conductivity, the temperature of the polymeric layer can significantly increase relative to the surrounding air on a hot day due to a combination of convection and direct sunlight absorption (ie, the layer). more than 30 ° C warmer than air temperature). If the polymeric layer has a high thermal conductivity, its temperature will only rise slightly with respect to the surrounding air (ie, about 1 to 30 ° C above the air temperature). Such increased temperature may accelerate polymer degradation due to Arrhenius-type acceleration kinetics and also accelerate evaporation, hydrolysis and / or leaching of additives. Since most polymers, particularly MDPE and HDPE1 have poor thermal conductivity, heat-accelerated degradation has a negative impact on the life of geotechnical articles, particularly CCSs, that use these polymers. Surprisingly, it has been found that when a mineral filler is mixed with these polymers, the thermal conductivity and thermal capacitance of the polymer increases. This significantly reduces the rate of heat accelerated degradation, resulting in longer service life and greater stability against UV-induced degradation. Better thermal conductivity also improves the tendency to resist creep under a combination of mechanical loads and UHH. Better thermal conductivity is particularly important for geotechnical applications in areas where CCS surface temperatures exceed 70 ° C or more. Typically, the warm areas of the globe located between 42 degrees north latitude and 42 degrees south latitude of the Equator have these temperature extremes. It also reduces degradation, which generally has Arrhenius's first-order acceleration kinetics. In specific embodiments, a polymeric layer comprises a high thermal conductivity filler that is selected from the group consisting of metal carbonates, metal sulfates, metal oxides, metals, minerals and metal-coated oxides, alumosilicates and mineral fillers.

The addition of mineral filler also reduces the polymer CTE. Yarn and fiber are the most effective in reducing CTE. Introducing mineral fillers into a polymeric layer also improves the processing quality of the layer. The presence of charge in the melt reduces heat build-up by reducing torque during kneading of melt, extrusion and molding. This is particularly important during melt kneading, which is a heat generating process that can degrade the polymer. Surprisingly, when the load is introduced, less mechanical energy is required for the melt kneading of one compound mass relative to the unloaded HDPE or MDPE, and therefore the relative output per unit energy increases, and Heat buildup in this compound throughout the extruder decreases. In addition, shear strength during combination and extrusion is lower than with HDPE. As a result, fewer gels are created, and less polymer degradation occurs. This allows the production of thinner strips under the same torque as the extruder and thus a higher production rate as measured per unit length per unit time.

Furthermore, it has surprisingly been found that when a polymeric layer comprises mineral filler and a UV or HALS absorber, there is a synergistic effect, so that the loss rate and degradation rate of the UV or HALS absorber decrease. This is attributed to lower heat build-up in the polymeric layer due to the better thermal conductivity conferred by the mineral filler. A polymeric layer may also comprise particles

barrier Barrier particles are inorganic particles with high barrier properties. The term "barrier properties" refers to the ability of inorganic particles to (1) reduce the diffusion rate of additives from the polymeric layer to the surrounding environment; (2) reduce the diffusion rate of hydrolysis agents such as water, protons and hydroxyl ions from the surrounding environment to the polymeric layer; and / or (3) reduce the production / mobility of free radicals and / or ozone into the polymer layer. The main cause of loss of additives during the life of the polymeric strip is due to diffusion, washing, hydrolysis or evaporation. This diffusion or degradation of additives depends, among other things, on their molecular weight, main chain structure, miscibility in the polymeric matrix, presence of ions and temperature. Improving the barrier properties of the polymeric strip thus improves the durability of the polymeric strip. Preferably the barrier particles are nanoparticles. In specific embodiments, the barrier particles are selected from the group consisting of clays, organo-modified clays, nanotubes, metal flakes, ceramic flakes, metal coated ceramic flakes and glass flakes. Preferably, the barrier particles are flakes that maximize surface area per mass unit. The polymeric layer comprising barrier particles is characterized by a slower rate of leaching, evaporation and hydrolysis of said additives relative to layers without the barrier particles. Barrier particles may be present in a charge of from about 0.01 to about 85 weight percent by weight of the polymeric layer. In more specific embodiments, barrier particles have a charge of from about 0.1 to about 70 weight percent of the polymeric layer. The permeability of the polymeric layer to molecules with a molecular weight less than about 1,000 Daltons should be at least 10 percent lower compared to a polymeric strip of the same composition but without the barrier particles. The permeability of the polymeric layer to molecules with a molecular weight of less than about 1,000 Daltons should be at least 25 percent lower compared to a polymer strip made of HDPE without barrier particles.

As indicated, each polymeric layer comprises a polymer. In specific embodiments, the polymer is selected from HDPE and medium density polyethylene (MDPE). In other embodiments, the polymer itself has better UHH resistance properties compared to virgin polyethylene. Such polymers are selected from the group consisting of: (i) ethylene-acrylic acid ester copolymers and terpolymers; (ii) ethylene ester copolymers and terpolymers of methacrylic acid; (iii) acrylic acid ester copolymers and terpolymers; (iv) aliphatic polyesters; (v) aliphatic polyamides; (vi) aliphatic polyurethanes; their mixtures; and mixtures thereof with at least one polyolefin. Commercially available ethylene-acrylic ester copolymers and terpolymers include Elvaloy ™ manufactured by Du-Pont or Lotryl ™ manufactured by Arkema. In specific embodiments, each polymeric layer in a polymeric strip is made of the same polymer.

A polymeric layer may also comprise integrated friction enhancing structures. Increased friction decreases the movement of the polymeric strip in relation to the GRM it sustains. These friction increasing structures are generally formed by embossing. The structures may comprise a pattern selected from the group consisting of textured patterns, embossed patterns, holes, finger extensions, hair extensions, wave extensions, co-extruded lines, points, mats and their combinations.

The polymeric strip may have a total thickness of from about 0.1 mm to about 5 mm and a total width of from about 10 mm to about 5,000 mm. In general, the average concentration of HALS, organic UV absorbers, and inorganic UV absorbers in the outer polymeric layer (s) is about 1.2 to about 10 times greater than the concentration. HALS, organic UV absorbers, and inorganic UV absorbers throughout the strip (ie including the internal polymeric layer (s)).

Thus, various embodiments of the polymeric strip used to prepare the CCS of the present disclosure are described. The polymeric strip may be a single layer or multilayer strip. In specific embodiments, the polymeric strip has at least one inner polymeric layer and at least one outer polymeric layer. The outer polymeric layer is exposed to direct sunlight, while the inner polymeric layer is not. In other specific embodiments, the polymeric strip has two outer polymeric layers. Each layer may comprise UHH resistant polymers, additives, fillers and / or barrier particles as described. Several specific embodiments are now further described.

One specific embodiment is a single layer UHH resistant polymeric strip. The polymeric strip comprises a polymer, UV and HALS absorbing particles. The polymer may be a polyolefin or UHH resistant polymer and combinations thereof. The polymeric strip may also comprise filler, pigments, dyes and / or barrier particles to ensure a stable polymer under UHH conditions. The polymeric strip has a vivid color. Even with multiple additives, the color of the polymeric strip is mainly determined by the pigments or dyes used to create the color. In another specific embodiment, the UHH-resistant polymeric strip is a multilayer strip and has at least one layer comprising up to 100% (w / w) MDPE or HDPE; up to 50% (w / w) low density linear polyethylene (LLDPE); up to 70% (w / w) load; and from 0.005 to 5% (w / w) of selected UV and HALS absorber additives; and from 0.005 to 50% (w / w) barrier particles.

In another specific embodiment, the UHH-resistant polymeric strip is a multilayer strip and has at least one layer comprising up to 100% (w / w) MDPE or HDPE; up to 100% (w / w) of ethylene acrylic or methacrylic acid copolymer or terpolymer; up to 70% (w / w) load; and from 0.005 to 50% (w / w) of selected UV and HALS absorber additives; and from 0.005 to 50% (w / w) barrier particles.

In another specific embodiment, the UHH-resistant polymeric strip is a multilayer strip and has at least one layer comprising a polymer, filler and a UV or HALS absorber. The layer may also comprise from 0.005 to 50% (w / w) of barrier particles. The layer exhibits at least 10% lower UV absorber extraction, evaporation and / or hydrolysis rate relative to an HD-PE layer comprising the same additive and the same dimensions. A method for preparing the layer (s) is presented.

and / or polymeric strip (s). The method comprises a melt kneading step of at least one polymer with at least one additive in an extruder. The extruder may be a multiple screw extruder, in particular a twin screw extruder. In additional embodiments, the extruder is a co-rotating twin screw extruder, particularly a co-rotating twin screw extruder characterized by an L / D ratio of about 20 to 50. The extruder may be equipped with at least one side feeder, at least one atmospheric opening (for steam and air removal) and optionally a vacuum opening for degassing volatile monomers and gaseous compounds. The mixture is then pumped downstream to form a film, strip, sheet, pellet, granule, powder or extruded article. A master mix comprising a plurality of additives may be prepared, wherein the master mix refers to a dispersion and / or concentrated solution of all or part of the additives in a polymeric carrier. The master mix of additives is fed by an extruder hopper and melted together with other ingredients of the composition. The melt is then pumped downstream into the extruder in a dedicated mixing zone. The feed can then be fed into a mixing zone by an upper or side feeder. The trapped air and adsorbed moisture are removed by the atmospheric opening. The mixture is further melt-kneaded until most of the agglomerates are deagglomerated, and the filler is evenly dispersed in the mixture. Volatiles and / or trapped by-products may be removed by the optional vacuum opening. The result is then pumped through a die to form pellets or a strip or directly shaped into the final polymeric strip. Alternatively, the pellets may be re-melted in a second extruder or molding machine and then shaped.

In another step, integrated friction enhancing structures are formed on the polymeric layer (s) and / or strip (s). The structures may be formed by embossing, puncturing or extrusion. In particular, embossing is by calender embossing.

Prior art polymers were prepared in a reactor. A reactor allows the combination of few monomers in one main structure. However, the preparation of a polymer in a reactor is different from the preparation of a polymer in an extruder. A reactor allows the manufacture of UV resistant polymers, such as ethylene acrylic acid copolymers and terpolymers; methacrylic acid ethylene ester copolymers and terpolymers; acrylic acid ester copolymers and terpolymers. However, a reactor does not allow the manufacture of a finely dispersed mixture of heat resistant polymers and strong UHH resistant polymers. A reactor does not allow dispersion of nanoparticles or charges. In particular, it is difficult to evenly disperse the load in a reactor. However, it is easy to evenly disperse filler, nanoparticles and more than one different polymer in one extruder. Extruder technology allows almost endless combinations. A multiple co-rotating screw extruder, and particularly a co-rotating twin screw extruder, allows very fine dispersion of fine particles and different polymers. Without such intense mixing, the short and long term properties of the resulting polymer are inferior.

A three-dimensional cell confinement system is formed with a plurality of UHH resistant polymeric strips. In general, each strip appears to have a waveform pattern with peaks and valleys. The peaks of one strip are joined to the valleys of another strip so that a hive-shaped pattern is formed. In other words, the strips are stacked parallel to each other and interconnected by a plurality of distinct physical joints, the joints being spaced apart by unjoined parts. Joints may be formed by welding, bonding, sewing or any combination thereof. In specific embodiments, the joints are welded by ultrasonic means. In other embodiments, the joints are welded by ultrasonic pressure-free means. In some embodiments, the distance between adjacent joints is from about 50 mm to about 1,200 mm.

The polymeric strips of the present disclosure have several desirable properties. By incorporating the load, they have better thermal conductivity to prevent temperature buildup as well as better weld quality. The load also reduces the CTE so that better dimensional stability is achieved. By incorporating the barrier particles, the leaching and / or evaporation of additives and the ingress of moisture, protons or hydroxyl ions into the polymeric strip are reduced. By using UV absorbing particles, better retention of UV resistance is achieved for as long as 100 years.

The CCSs of this exhibition have better welding resistance and durability. Weld strength is at least 10% higher compared to a polymer strip consisting of virgin HDPE and an equivalent filler of additives. When welded strips are subjected to long-term load, their failure rate is at least 10% lower compared to welded strips consisting of virgin HDPE and an equivalent load of additives. In addition, the welding cycle is at least 10% faster compared to a polymer strip consisting of virgin HDPE and an equivalent filler of additives. This better weldability is more significant when using ultrasonic welding because polyethylene is relatively difficult to weld by ultrasonic welding due to its low density, crystallinity and low coefficient of friction.

It is important to protect the welds from deterioration. They are relatively weak points in the CCS, and when one weld fails, its load shifts to the other welds, increasing its load and increasing the likelihood that it will also fail. Forming welds with higher weld resistance prevents this from happening.

CCSs of the present exposure also have a lower rate of extraction, evaporation or hydrolysis. They have an extraction rate of at least 10% lower HALS and / or organic UV absorbers compared to an HDPE strip of the same thickness and the same average concentration of HALS and UV absorbers across the strip. HDPE (compared to the CCS layers of this exposure) when extraction is performed at room temperature in water for a period of about 6 to 24 months. The residual content of the polymer may be determined by GC, HPLC or similar methods.

CCSs also have at least 10% less degradation as measured by delta E color change and loss of elasticity (measured by elongation at break) compared to an HDPE strip of the same thickness and average concentration of HALS and / or organic UV absorbers throughout the HDPE strip.

The present disclosure will be further illustrated in the following non-limiting working examples, it is to be understood that these examples are intended to be illustrative only and that the exposure should not be limited to the materials, conditions, process parameters and others cited herein. All proportions are by weight, unless otherwise indicated. EXAMPLES Example 1

Five UHH resistant mixtures, INV1 - INV5, and a reference mixture were prepared. Their compositions are shown in TABLE 1. In addition, each mixture comprised 0.5% T1O2 pigment (Kronos ™ 2222 manufactured by Kronos) and 0.2% PV Fast Brown HFR ™ brown pigment (manufactured by Clariant). The polymers, additives and pigments were fed to the main hopper of a co-rotating twin screw extruder operating at 100 - 400 RPM at a drum temperature of 180 to 240 degrees Celsius. The polymers were melted, and the additives were dispersed by at least one kneading zone. The load was provided by a side feeder. Steam and gases were removed through an atmospheric opening, and the product was pelleted by a filament pelletizer. TABLE 1. Composition of polymers

Ingredient Reference 1 INV1 INV2 INV3 INV4 INV5 HDPE (Kg) 100 100 100 50 50 50 LLDPE (Kg) 0 0 0 0 50 50 Ethylene Acrylate (Kg) 0 0 0 50 0 0 Talc (Kg) 0 20 20 20 20 20 Organic UV Absorber (Kg) 0.15 0.5 0.5 0.5 0.5 0.5 0.5 Inorganic UV Absorber (Kg) 0 0 1 1 1 1 HALS (Kg) 0.15 0.5 0.5 0.5 0.5 0.5 Nano-clay (Kg) 0 0 0 0 0 1

HDPE Resin - HDPE M 5010 manufactured by Dow.

LLDPE Resin - LL 3201 manufactured by Exxon Mobil.

Ethylene Acrylate Resin - Lotryl ™ 29MA03 manufactured by Arkema.

Talc - Iotalk ™ superfine made by Yokal.

Organic UV Absorber - Tinuvin ™ 234 manufactured by Ciba.

Inorganic UV Absorber - SACHTLEBEN ™ Hombitec RM 130F TN from

Sachtleben HALS - Chimassorb ™ 944 manufactured by Ciba. Nano-Clay - Nanomer ™ 131PS manufactured by Nanocor.

Next, five ST1 - ST5 polymeric strips and one reference strip were prepared. All strips were fabricated in a sheet extrusion line comprising one main single screw extruder for the core layer and one secondary single screw extruder for the two outer layers. The thickness of the core layer was 0.8 mm, and the outer layers were 0.20 mm thick each. The composition of the strips is described in TABLE 2. The names of the polymers in each layer are in accordance with TABLE 1.

TABLE 2. Composition of strips

Strip Number Reference A ST1 ST2 ST3 ST4 ST5 Outer Layer 1 Reference 1 INV1 INV2 INV3 INV4 INV5 Core Layer Reference 1 HDPE HDPE HDPE HDPE HDPE Outer Layer 2 Reference 1 INV1 INV2 INV3 INV4 INV5

HDPE Resin - HDPE M 5010 manufactured by Dow. No UV absorbers or HALS additives.

Evaluation

Strips were evaluated for accelerated aging UHH resistance on a Heraeus Xenotest 1200 W WOM, Relative Humidity = 60%, Black Panel = 60SC, 102 minutes dry cycle, 18 minutes wet cycle. The color difference (delta E) and relative loss of elongation at break ((initial elongation minus final elongation) divided by initial elongation) were measured after 10,000 hours of aging. The results are summarized in TABLE 3. TABLE 3. Aging Test Results

Strip number RefA ST1 ST2 ST3 ST4 ST5 Delta E 22 12 10 6 10 8 Relative loss of elongation at break (%) 60 20 17 12 12 12

Example 2

Five mixtures, INV6 - INV10, and one reference mixture were prepared. Their compositions are shown in TABLE 4. In addition, each mixture comprised 0.5% TiO2 pigment (Kronos ™ 2222 manufactured by Kronos) and 0.2% PV Fast Brown HFR ™ brown pigment (manufactured by Clariant ). The polymers, additives and pigments were fed to the main hopper of a co-rotating twin screw extruder operating at 100 - 400 RPM at a drum temperature of 260 to 285 degrees Celsius.

The polymers were melted, and the additives were dispersed over at least one kneading zone. The load was provided by a side feeder. Steam and gases were removed through an atmospheric opening, and the product was pelleted by a filament pelletizer.

TABLE 4. Composition of polymers

Ingredient Reference 2 INV6 INV7 INV8 INV9 INV9 INV10 HDPE Functionalized with MA (kg) 0 100 100 70 40 40 Virgin HDPE (Kg) 100 0 0 0 0 0 LLDPE (Kg) 0 0 0 0 30 0 Ethylene Acrylate (Kg) 0 0 0 0 0 30 Recycled PET (Kg) 0 25 25 25 25 25 Talc (Kg) 0 20 0 20 20 20 Organic UV Absorber (Kg) 0.15 0.35 0.15 0.15 0.15 0 , 15 Inorganic UV Absorber (Kg) 0 0 1 1 1 1 HALS (Kg) 0.15 0.15 0.15 0.15 0.15 0.15 Nano-clay (Kg) 0 0 0 1 0 1 Resin HDPE Functionalized with MA - HDPE M 5010 manufactured by Dow, grafted with 0.25 - 0.40% maleic anhydride (MA) into a reactive extruder.

Virgin HDPE - HDPE M 5010 manufactured by Dow. Not functionalized with MA.

Ethylene Acrylate Resin - Lotryl ™ 29MA03 manufactured by Arkema. Talc - Iotalk ™ superfine made by Yokal. Organic UV Absorber - Tinuvin ™ 234 manufactured by Ciba. Inorganic UV Absorber - SACHTLEBEN ™ Hombitec RM 130F TN from Sachtleben.

HALS - Chimassorb ™ 944 manufactured by Ciba. Nano-Clay - Nanomer ™ 131PS manufactured by Nanocor.

Next, five ST6 - ST10 polymeric strips and a reference strip were prepared. All strips were fabricated in a sheet extrusion line comprising one main single screw extruder for the core layer and one secondary single screw extruder for the two outer layers. The thickness of the core layer was 0.8 mm, and the outer layers were 0.20 mm thick each. The core layer was prepared with HDPE M 5010 manufactured by Dow, and the outer layers were prepared with the compositions according to TABLE 4. Their compositions were similar to those shown in TABLE 2, where RefB had two outer layers with Reference composition 2, ST6 had two outer layers with the composition of INV6, and so on. Evaluation

The strips were evaluated for UHH resistance in areas

Hot The strips were heated in a phono at 11 ° C for seven days, and the relative loss of elongation at break was then measured. This simulated the loss of additives by evaporation.

Then, to determine the resistance to UHH, the strips were subjected to moisture and heat by aging in 859C water for seven days to allow the extraction and hydrolysis of the additives. The strips were then exposed to artificial sunlight on a Heraeus Xenotest 1200 W WOM, Relative Humidity = 60%, Black Panel = 60eC, 102 minutes dry cycle, 18 minutes wet cycle. The color difference (delta E) and relative loss of elongation at break were measured after 10,000 hours of aging. The results are summarized in TABLE 5.

TABLE 5. Aging Test Results

Strip number RefB ST6 ST7 ST8 ST9 ST1 0 Relative loss of elongation at break after oven heating (%) 44 21 25 15 16 12 Delta E after aging with moisture and heat 28 12 11 10 16 9 Relative loss at elongation at break after aging with moisture and heat (%) 58 24 29 32 23 23

Twenty strips of each composition, 100 mm in length, were then welded by a 20 MHz ultrasonic welder to obtain 10 pairs. Five pairs of each composition were randomly selected, and their tensile strengths were measured 48 hours after welding (T = 0). The five pairs were then aged in an oven at 110 ° C for 21 days, and their tensile strengths were then measured again (T = 21 d). Measurement means are given in TABLE 6.

TABLE 6. Weld resistance after thermal aging

Strip Number RefB ST6 ST7 ST8 ST9 ST10 Solder Resistance (N) T = O 1380 1700 1550 1830 1750 1750 Solder Resistance (N) T = 21 d at 110-C 450 1230 1240 1650 1430 1510

Although particular modalities have been described, alternatively

Substantive changes, variations, improvements, and equivalents that are or may be currently foreseen may arise for applicants or those skilled in the art. Therefore, the appended claims, as filed and as may be amended, are intended to encompass all such substantial alternatives, modifications, variations, improvements and equivalents.

Claims (39)

Durable cell confinement system comprising a plurality of polymeric strips; each polymeric strip comprising at least one outer polymeric layer and at least one inner polymeric layer, wherein at least one layer is more resistant to UV light, moisture or heat (UHH) than virgin high density polyethylene (HDPE); and wherein the at least one outer polymeric layer comprises a UV absorber or blocked amine light stabilizer (HALS). A cell confinement system according to claim 1, wherein each polymeric strip comprises first and second outer polymeric layers, wherein all inner polymeric layers lie between the first outer polymeric layer and the second layer. polymeric A cell confinement system according to claim 1, wherein the at least one inner polymeric layer contains additives in an amount of less than 0.5 weight percent based on the weight of the at least one layer. internal polymeric. A cell confinement system according to claim 1, wherein at least one outer layer of each polymeric strip also comprises an additive selected from the group consisting of antioxidants, pigments, dyes, carbon black and barrier particles. A cell confinement system according to claim 4, wherein the antioxidant is selected from the group consisting of blocked phenols, phosphates, phosphates and aromatic amines. Cellular confinement system according to claim 4, wherein the pigment or dye does not make the polymeric strip black or dark gray. A cell confinement system according to claim 4, wherein the barrier particles are selected from the group consisting of clays, organo-modified clays, nanotubes, metal flakes, ceramic flakes, ceramic coated flakes. Metal and glass flakes. A cell confinement system according to claim 1, wherein the at least one outer polymeric layer comprises the UV1 absorber which is an inorganic particle comprising a material selected from the group consisting of titanium salts, titanium oxides, zinc oxides, zinc halides and zinc salts. A cell confinement system according to claim 8, wherein the inorganic UV absorber particles are nanoparticles having an average diameter of about 5 to about 100 nanometers. A cell confinement system according to claim 1, wherein at least one layer also comprises a charge. A cell confinement system as claimed in claim 10, wherein the charge is in the form of yarn or fiber and has an average particle size of less than 50 microns. A cell confinement system according to claim 10, wherein the charge is selected from the group consisting of mineral fillers, metal oxides, metal carbonates, metal sulfates, metal phosphates, metal silicates, metal borates, metal hydroxides, silica, silicates, aluminates, alumosilicates, fibers, wires, industrial ash, concrete or cement dust, natural fibers, kenaf, hemp, flax, ramie, sisal, newprint fibers, paper making sludge, sawdust, flour wood, carbon, aramid and mixtures thereof. The cell confinement system of claim 10, wherein the filler is a mineral selected from the group consisting of calcium carbonate, barium sulphate, dolomite, alumina trihydrate, talc, bentonite, kaolin, wollastonite. , clay, and mixtures thereof. A cell confinement system according to claim 10, wherein the filler is surface treated with a collating agent or coupling agent selected from the group consisting of fatty acids, esters, amides and their salts; silicone-containing polymer or oligomer, organometallic compounds, titanates, silanes and zirconates. A cell confinement system according to claim 10, wherein the charge has high thermal conductivity and is selected from the group consisting of metal carbonates, metal sulfates, metal oxides, metals, minerals and oxides coated with metals, alumosilicates and mineral fillers. A cell confinement system according to claim 1, wherein the at least one outer polymeric layer comprises the UV absorber, which is a benzotriazole or a benzophenone. A cell confinement system according to claim 1, wherein the UV absorber or HALS is present in an amount of from about 0.01 to about 2.5 percent by weight of at least an outer layer, based on the weight of at least one outer layer. A cell confinement system as claimed in claim 1, wherein the at least one inner polymeric layer also comprises a blocked UV absorber and amine light stabilizer in the amount of 0 to about 0.25. weight percent based on the weight of at least one inner polymeric layer. A cell confinement system according to claim 1, wherein at least one polymeric layer of each polymeric strip independently comprises a polymer selected from the group consisting of high density polyethylene (HDPE); medium density polyethylene (MDPE); ethylene ester acrylic acid copolymers and terpolymers; methacrylic acid ethylene ester copolymers and terpolymers; acrylic acid ester copolymers and terpolymers; aliphatic polyesters; aliphatic polyamides; aliphatic polyurethanes; their mixtures; and mixtures thereof with at least one polyolefin. A cell confinement system according to claim 1, wherein at least one polymeric layer of each polymeric strip comprises a friction enhancing structure selected from the group consisting of textured patterns, embossed patterns, holes, extensions in finger-shaped, hair-like extensions, wave-like extensions, co-extruded lines, dots, mats and their combinations. A cell confinement system according to claim 1, wherein each polymeric strip has a total thickness of from about 0.1 mm to about 5 mm, a total width of from about 10 mm to about 500 mm. mm and a total length of about 10 mm to about 5,000 mm. A cell confinement system according to claim 1, wherein each polymeric strip comprises first and second outer polymer layers, wherein an outer polymeric layer has a higher concentration of UV absorbers and HALS additives than the other outer polymeric layer. A cell confinement system according to claim 1, wherein at least one layer of each polymeric strip comprises up to 100 weight percent MDPE or HDPE; up to 50 weight percent linear low density polyethylene (LLDPE); up to 70 percent by weight of mineral filler; from 0.005 to 5 weight percent of selected additives from the group consisting of UV and HALS absorbers; and from 0.005 to 50 weight percent barrier particles. A cell confinement system as claimed in claim 1, wherein at least one layer of each polymeric strip comprises up to 100 weight percent MDPE or HDPE; up to 100 weight percent of ethylene acrylic acid ester copolymer or terpolymer; up to 70 percent by weight of mineral filler; from 0.005 to 5 weight percent of additives selected from the group consisting of UV and HALS absorbers; and from 0.005 to 50 weight percent barrier particles. 25. Durable cell confinement system comprising a plurality of single layer polymeric strips, each polymeric strip comprising a polymer, organic UV-absorbing particles and blocked amine light stabilizer (HALS) in an amount sufficient to ensure color and properties. stable physical conditions in the external environment for at least 2 years under harsh weather conditions. A cell confinement system as claimed in claim 25, wherein each polymeric strip also comprises a selected charge from the group consisting of metal carbonates, metal sulfates, metal oxides, metals, minerals and metal-coated oxides. , aluminosilicate and mineral fillers. A cell confinement system according to claim 25, wherein each polymeric strip also comprises barrier particles selected from the group consisting of clays, organo-modified clays, nanotubes, metal flakes, ceramic flakes, coated ceramic flakes. with metal and glass flakes. A cell confinement system according to claim 25, wherein the polymer is selected from the group consisting of ethylene-acrylic acid ester copolymers and terpolymers. A cell confinement system according to claim 25, wherein each polymeric strip also comprises a friction enhancing structure selected from the group consisting of textured patterns, embossed patterns, holes, finger-shaped extensions. , hair extensions, wave extensions, co-extruded lines, points, mats and their combinations. A cell confinement system as claimed in claim 25 further comprising a pigment or dye other than black or dark gray. 31. Cell confinement system which is resistant to ultraviolet light, heat or moisture, comprising a plurality of polymeric strips; each polymeric strip comprising at least one polymeric layer containing a UV absorber and a polymer selected from the group consisting of ethylene-acrylic acid ester copolymers and terpolymers; methacrylic acid ethylene ester copolymers and terpolymers; acrylic acid ester copolymers and terpolymers; aliphatic polyesters; aliphatic polyamides; aliphatic polyurethanes; their mixtures; and mixtures thereof with at least one polyolefin; wherein a first polymeric strip is stacked parallel to a second polymeric strip and joined to a second polymeric strip by a plurality of distinct physical joints, the joints being spaced apart by unjoined portions of the polymeric strips. Cellular confinement system according to claim 31, wherein the joints are formed by welding, gluing, sewing or any combination thereof. A cell confinement system as claimed in claim 31, wherein the joints are formed by ultrasonic means. A cell confinement system according to claim 31, wherein the distance between the joints is from about 50 mm to about 1,200 mm. A cell confinement system as claimed in claim 31, wherein the maximum weld strength of a joint is at least 10% greater than the weld strength of a joint made with a HDPE polymer strip. virgin and an equal charge of UV absorber. A cell confinement system according to claim 31, wherein the failure rate of a joint is at least 10% lower than the failure rate of a joint made with a polymeric strip consisting of virgin HDPE and a equal charge of UV absorber. A cell confinement system according to claim 31, wherein the first polymeric strip has a thermal expansion coefficient of 150 ppm / sC or less. Durable cell confinement system comprising a plurality of UV, moisture or heat resistant (UHH) polymeric strips, each polymeric strip comprising at least one outer polymeric layer and at least one inner polymeric layer; wherein the at least one outer polymeric layer comprises a polymeric mixture of (a) ethylene acrylate polymer and (i) high density polyethylene (HDPE) or (ii) medium density polyethylene (MD-PE) ; and (b) (i) a UV absorber or (ii) a blocked amine light stabilizer (HALS). A cell confinement system as claimed in claim 38, wherein the ethylene acrylate polymer is selected from the group consisting of ethylene acrylic acid ester copolymers and terpolymers; and ethylene ester copolymers and terpolymers of methacrylic acid.