Polymer film tube

Abstract

A tube comprising a first channel and a second channel, wherein each of the first channel and the second channel extends along the longitudinal axis of the tube, and wherein the tube is composed of a first heat-sealable polymer film A and a second heat-sealable polymer film B. The polymer films A and B each have a first surface (A1, B1) and a second heat-sealable surface (A2, B2), respectively. The polymer films A and B are arranged so that the heat-sealable surfaces A2 and B2 contact and adhere to each other by a heat-seal bond, and the heat-seal bond does not extend over the entire surface area of ​​the heat-sealable surfaces A2 and B2. A method of making a tube, a kit comprising a plurality of polymer films for forming a tube, and a method for delivering an injectable chemical using a tube are also described.

Description

[0001] The present invention relates to a polymer film tube and a method for making the same. The present invention also relates to a kit comprising a plurality of polymer films for forming a polymer film tube. The polymer film tube is particularly useful in the delivery of injectable chemicals, such as in mining and construction applications.

[0002] Pipes made of polymer films are used in many industrial applications. For example, polymer film pipes can be injected with chemicals to strengthen the walls of boreholes (such as those in mining operations), or the walls of pipelines, shafts, or tunnels. The use of such polymer pipes to deliver injectable chemicals can be used to anchor, reinforce, and control gas, water, and formations in underground locations, such as reinforcing fractured formations and / or preventing water from entering. In addition to ground stabilization, this technology can also be used in renovation and construction projects, such as for repairing or filling cavities or cracks in structures. A variety of injectable chemicals are used for this purpose, including polyurethane, silicate, and phenolic-based resin systems.

[0003] The polymer film that can be heat-sealed on its two surfaces can be used for forming a tubular structure by heat-sealing the first heat-sealable surface to the second heat-sealable surface with an overlapping seal arrangement along the seam of the pipe. However, the polymer film with two heat-sealable surfaces is more challenging technically, expensive to manufacture, and due to potential jaw adhesion, there may be process difficulties in the manufacture of the pipe. An alternative structure uses a polymer film with a heat-sealable surface and a non-heat-sealable surface, and by pre-swelling via using a solvent to modify the non-heat-sealable surface and at a relatively high temperature, the film is sealed or welded together (commonly referred to as high temperature solvent welding) to form an overlapping seal. Another alternative structure uses a polymer film without a heat-sealable surface, and by pre-swelling using a solvent and at high temperatures, the film is welded together to form an overlapping seal. However, the shortcoming of these alternative structures is that the sealing integrity along the seam length lacks consistency and the deformation of the plastic film caused by the higher sealing temperature and the slower and more expensive production of the pipe.

[0004] It would be desirable to address one or more of these problems and provide a polymer film tube that is efficient and economical to manufacture and use and that exhibits excellent seal integrity along the length of the seal and preferably also avoids deformation.

[0005] According to a first aspect of the present invention, there is provided a tube comprising a first channel extending along a longitudinal axis of the tube, wherein:

[0006] (i) the tube is composed of a first heat-sealable polymer film A and a second heat-sealable polymer film B,

[0007] (ii) the polymer film A has a first surface A1 and a second heat-sealable surface A2,

[0008] (iii) the polymer film B has a first surface B1 and a second heat-sealable surface B2,

[0009] (iv) the polymer film A comprises edges Aa and Ab, and the polymer film B comprises edges Ba and Bb, wherein the edges Aa, Ab, Ba and Bb extend along the longitudinal axis of the tube,

[0010] (v) the polymer films A and B are arranged so that the heat-sealable surfaces A2 and B2 are in contact and adhered to each other by a heat-seal bond which does not extend over the entire surface area of ​​at least one of the heat-sealable surfaces A2 and B2 (preferably, wherein the at least one heat-sealable surface is at least the heat-sealable surface B2), and

[0011] (vi) Polymer Film A is adhered to Polymer Film B by overlapping first and second heat seal bonds (HSB1 and HSB2) to define the tube and its first channel.

[0012] According to a second aspect of the present invention, there is provided a tube according to the first aspect, comprising a first channel and a second channel, wherein each of the first channel and the second channel extends along a longitudinal axis of the tube, and wherein:

[0013] (i) the tube is composed of a first heat-sealable polymer film A and a second heat-sealable polymer film B,

[0014] (ii) the polymer film A has a first surface A1 and a second heat-sealable surface A2,

[0015] (iii) the polymer film B has a first surface B1 and a second heat-sealable surface B2,

[0016] (iv) the polymer film A comprises edges Aa and Ab, and the polymer film B comprises edges Ba and Bb, wherein the edges Aa, Ab, Ba and Bb extend along the longitudinal axis of the tube,

[0017] (v) the polymer films A and B are arranged so that the heat-sealable surfaces A2 and B2 are in contact and adhered to each other by a heat-seal bond which does not extend over the entire surface area of ​​the heat-sealable surfaces A2 and B2,

[0018] (vi) polymer film A is adhered to polymer film B by overlapping first and second heat seal bonds (HSB1 and HSB2) to define said tube and said first channel thereof, and

[0019] (vii) polymer film A is further adhered to polymer film B by a third heat seal bond (HSB3) between said heat sealable surfaces A2 and B2 such that said third heat seal bond defines a second channel comprising a first wall and a second wall extending along the longitudinal axis of said tube.

[0020] The tube of the second aspect of the invention has particular utility for delivering two-component injectable chemical systems where the two components need to be kept separate until their point of application where they come into contact so as to chemically react to provide the desired compound at a predetermined location. Such injectable chemical systems include, for example, two-component polyurethane or silicate resin systems.

[0021] Advantageously, the first surface A1 of the polymer film A and the first surface B1 of the polymer film B are not heat-sealable.

[0022] Preferably, polymer film A and polymer film B are selected from composite films comprising a polymer base layer and a polymer heat-sealable layer. Said base layer suitably constitutes said non-heat-sealable surface of the polymer film. Preferably, the heat-sealable layer is directly arranged on the base layer, i.e. without any intermediate layer.

[0023] As used herein, the term "heat-sealable surface" refers to the ability to form a heat-seal bond by contacting two surfaces for a period of no more than one minute (preferably in the range of 0.5 seconds to 30 seconds) at a temperature not exceeding 200°C (preferably in the range of 100°C to 200°C) and a pressure not exceeding 100 psi (preferably in the range of 10 psi to 60 psi), wherein the resulting heat-seal bond strength is at least 10 g / mm (preferably at least 20 g / mm, preferably at least 30 g / mm). As used herein, the term "non-heat-sealable surface" refers to a surface that does not have this ability.

[0024] Each of the polymer films A and B is a self-supporting film or sheet, which means a film or sheet capable of existing independently without a supporting substrate.

[0025] The substrate can be formed by any suitable film-forming polymer material. Thermoplastic polymer materials are preferred. These materials include homopolymers or copolymers of 1-olefins (e.g., ethylene, propylene, and butene-1-ene), polyamides, polycarbonates, PVC, PVA, polyacrylates, cellulose, and polyesters. Polyolefins, polyamides, and polyesters are preferred, particularly polyesters. The substrate should be a self-supporting film or sheet.

[0026] The base layer is preferably uniaxially or biaxially oriented, preferably biaxially oriented.

[0027] It will be understood from the disclosure below that the base layer can be described as semi-crystalline. As used herein, the term "semi-crystalline" refers to a film that exhibits a crystallinity of at least 5%, preferably at least 10%, preferably at least 15%, preferably at least 20%, preferably at least 25%, and typically not more than 50% or 45% or 40%.

[0028] Thus, the base layer is preferably formed from a film-forming thermoplastic polyester material. Synthetic linear polyesters are preferred. It will be appreciated that the base layer polyester is crystallizable. Suitable polyesters include those derived from one or more dicarboxylic acids, such as terephthalic acid, isophthalic acid, phthalic acid, 2,5-, 2,6- or 2,7-naphthalenedicarboxylic acid, 4,4'-diphthalic acid, hexahydro-terephthalic acid, 1,10-decanedicarboxylic acid, in particular aliphatic dicarboxylic acids, including those of the general formula C n H 2n (COOH) 2 those of the type in which n is 2 to 8, such as succinic acid, glutaric acid, sebacic acid, adipic acid, azelaic acid, suberic acid or pimelic acid; and those derived from one or more diols, in particular aliphatic or cycloaliphatic diols, such as ethylene glycol, 1,3-propylene glycol, 1,4-butanediol, neopentyl glycol and 1,4-cyclohexanedimethanol (CHDM).

[0029] The dicarboxylic acid component of the base polyester preferably comprises at least one aromatic dicarboxylic acid, preferably selected from terephthalic acid and 2,6-naphthalene dicarboxylic acid, preferably terephthalic acid, and optionally also comprises a second different dicarboxylic acid, preferably selected from the above dicarboxylic acids, and preferably selected from aromatic dicarboxylic acids, especially isophthalic acid, and the above aliphatic diacids. Thus, the polyester is preferably derived from an aromatic dicarboxylic acid, preferably terephthalic acid or 2,6-naphthalene dicarboxylic acid, preferably terephthalic acid. Preferably, the dicarboxylic acid component of the base polyester comprises only one aromatic dicarboxylic acid, preferably terephthalic acid or 2,6-naphthalene dicarboxylic acid, and preferably terephthalic acid.

[0030] The glycol component of the base polyester preferably comprises at least one aliphatic diol, at least one of which is ethylene glycol. Preferably, the glycol component of the base polyester is an aliphatic diol, preferably ethylene glycol.

[0031] Preferred base polyesters are selected from polyethylene terephthalate (PET) and polyethylene naphthalate (PEN), or PET-based or PEN-based copolyesters. Polyethylene terephthalate (PET) or its copolyesters are particularly preferred. Preferably, the base polyester is PET.

[0032] The film-forming polymer resin is the major component of the base layer and accounts for at least 70 wt %, preferably at least 80 wt %, preferably at least 85 wt %, preferably at least 90 wt %, preferably at least 95 wt %, more typically at least 98 wt %, more typically at least 99 wt % of the total weight of the base layer.

[0033] The intrinsic viscosity of the polyester from which the base layer is made is preferably at least about 0.60, preferably at least about 0.61, preferably at least 0.62, preferably at least 0.63, preferably at least 0.64, preferably at least 0.65, preferably at least about 0.70, preferably at least about 0.75. Preferably, the intrinsic viscosity of the base layer polyester does not exceed 0.85, preferably does not exceed 0.83. Using a polyester with too high a viscosity may lead to difficulties in film manufacturing and / or require dedicated, more durable film-forming equipment. For example, increasing the viscosity too much may mean that it is appropriate to reduce the output (i.e., reduce the amount of polyester extruded per unit time, which results in a less economical process) or increase the extrusion temperature to reduce the viscosity of the melt (which in turn may lead to thermal degradation of the polymer and loss of related properties) in order to achieve stable film production.

[0034] The formation of the polyester is conveniently accomplished in a known manner by condensation or transesterification, usually at temperatures up to about 295° C. In a preferred embodiment, solid state polymerization may be used to increase the intrinsic viscosity of the polyester to the desired value using conventional techniques well known in the art, such as the use of a fluidized bed (e.g., a nitrogen fluidized bed or a vacuum fluidized bed using a rotary vacuum dryer).

[0035] The base layer may also include any other conventional additives for making polymer films, particularly polyester films. Thus, agents such as particulate fillers, hydrolysis stabilizers, antioxidants, UV stabilizers, crosslinkers, dyes, lubricants, free radical scavengers, heat stabilizers, surfactants, gloss improvers, degradation aids, viscosity modifiers and dispersion stabilizers may be appropriately incorporated. Particulate fillers, hydrolysis stabilizers (e.g. glycidyl esters of branched monocarboxylic acids) and antioxidants (e.g. hindered phenols, secondary aromatic amines and hindered amines) are particularly useful, and suitable additives in this regard are disclosed in WO-2012 / 120260-A, the disclosure of which is incorporated herein by reference. UV stabilizers are also particularly useful.

[0036] As is known in the art, particulate fillers can improve handling and windability and / or adjust optical properties during manufacturing. The particulate filler is typically a particulate inorganic filler (e.g., metal or metalloid oxides, such as aluminum oxide, titanium dioxide, talc and silica (particularly precipitated or diatomaceous earth silica and silica gel), calcined china clay and alkali metal salts, such as carbonates and sulfates of calcium and barium). The particulate inorganic filler is preferably finely divided, and its volume distribution median particle size (equivalent spherical diameter corresponding to 50% of the volume of all particles, read on a cumulative distribution curve that relates volume % to particle diameter, usually referred to as the "D (v, 0.5)" value) is preferably in the range of 0.01 to 5 μm, more preferably 0.05 to 1.5 μm, particularly preferably 0.15 to 1.2 μm. Preferably, at least 90% by volume, more preferably at least 95% by volume of the inorganic filler particles are within the range of ±0.8 μm, particularly ±0.5 μm, of the volume distribution median particle size. The particle size of the filler particles can be measured by electron microscopy, Coulter counter, sedimentation analysis, and static or dynamic light scattering. Laser diffraction-based techniques are preferred. The conventionally used additives described above can be introduced into the polymer in a conventional manner. For example, by mixing with the monomer reactants from which the film-forming polymer is derived, or by mixing in an extruder, the components are mixed with the polymer, subsequently cooled, and usually comminuted into particles or fragments. Masterbatch compounding techniques can also be used.

[0037] The heat sealable layer is capable of forming a heat seal bond with the base layer. The polymeric material of the heat sealable layer is capable of softening to a sufficient extent when heated so that its viscosity becomes low enough to allow sufficient wetting so that it adheres to the surface to which it is bonded.

[0038] The heat sealable layer can be formed by any suitable film-forming polymer material. Thermoplastic polymer materials are preferred, including polyolefins, polyamides and polyesters. Polyesters are preferred, particularly copolyesters derived from one or more dicarboxylic acids or their lower alkyl diesters and one or more of the above-mentioned ethylene glycols.

[0039] Preferably, the heat sealable layer is formed from a copolyester derived from at least 3 monomer repeating units, at least one of which is an aromatic dicarboxylic acid, and at least one of which is an aliphatic diol.

[0040] In a first preferred embodiment, hereinafter referred to as embodiment B1, the heat sealable layer is formed from a copolyester derived from an aliphatic glycol and at least two aromatic dicarboxylic acids, preferably terephthalic acid and a second aromatic dicarboxylic acid, preferably isophthalic acid. Preferred copolyesters are derived from ethylene glycol, terephthalic acid and isophthalic acid. The preferred molar ratio of the terephthalic acid component to the isophthalic acid component is in the range of 50:50 to 90:10, preferably in the range of 65:35 to 85:15. In a particularly preferred embodiment, the copolyester is a copolyester of ethylene glycol with about 82 mol % of terephthalate and about 18 mol % of isophthalate.

[0041] In a second preferred embodiment, hereinafter referred to as embodiment B2, the heat sealable layer is formed from a copolyester derived from an aliphatic diol and a cycloaliphatic diol with one or more (preferably one) dicarboxylic acids (preferably an aromatic dicarboxylic acid). Examples include copolyesters of terephthalic acid with aliphatic diols and cycloaliphatic diols (particularly ethylene glycol and 1,4-cyclohexanedimethanol). The preferred molar ratio of cycloaliphatic diol to aliphatic diol is in the range of 10:90 to 60:40, preferably in the range of 20:80 to 40:60, more preferably from 30:70 to 35:65. In a preferred embodiment, this copolyester is a copolyester of terephthalic acid with approximately 33 mol% of 1,4-cyclohexanedimethanol and approximately 67 mol% of ethylene glycol. An example of such a polymer is PETG TM 6763 (Eastman), which comprises a copolyester of terephthalic acid, about 33% 1,4-cyclohexanedimethanol and about 67% ethylene glycol, and which is always amorphous.

[0042] In a third preferred embodiment, hereinafter referred to as embodiment B3, the heat sealable layer is composed of a copolyester derived from an aromatic dicarboxylic acid and an aliphatic dicarboxylic acid (particularly a copolyester of the general formula C n H 2n (COOH) 2 The preferred aromatic dicarboxylic acid is terephthalic acid. The preferred aliphatic dicarboxylic acid is selected from sebacic acid, adipic acid and azelaic acid. The concentration of the aromatic dicarboxylic acid present in the copolyester is preferably in the range of 45 to 80 mol%, more preferably 50 to 70 mol%, in particular 55 to 65 mol%, based on the dicarboxylic acid component of the copolyester. The concentration of the aliphatic dicarboxylic acid present in the copolyester is preferably in the range of 20 to 55 mol%, more preferably 30 to 50 mol%, in particular 35 to 45 mol%, based on the dicarboxylic acid component of the copolyester.

[0043] Particularly preferred examples of such copolyesters are (i) copolyesters of azelaic acid and terephthalic acid with an aliphatic glycol (preferably ethylene glycol); (ii) copolyesters of adipic acid and terephthalic acid with an aliphatic glycol (preferably ethylene glycol); and (iii) copolyesters of sebacic acid and terephthalic acid with an aliphatic glycol (preferably butanediol). Preferred polymers include those having a glass transition point (T g ) and a melting point of 117°C (T m ) of sebacic acid / terephthalic acid / butylene glycol (preferably having a relative molar ratio of 45-55 / 55-45 / 100, more preferably 50 / 50 / 100), and having a T of -15°C g and 150°C T m A copolyester of azelaic acid / terephthalic acid / ethylene glycol (preferably having a relative molar ratio of the components of 40-50 / 60-50 / 100, more preferably 45 / 55 / 100).

[0044] In a fourth preferred embodiment, hereinafter referred to as embodiment B4, the additional heat sealable layer is formed from ethylene vinyl acetate (EVA). Suitable EVA polymers can be Elvax TM The resins are available from DuPont. Typically, these resins have a vinyl acetate content in the range of 9% to 40%, and typically 15% to 30%.

[0045] Embodiment B1 is a particularly preferred embodiment of the heat-sealable layer.

[0046] The film-forming polymer resin is the main component of the heat sealable layer and accounts for at least 70wt% of the total weight of the heat sealable layer, preferably at least 80wt% of the total weight of the heat sealable layer, preferably at least 85wt%, preferably at least 90wt%, preferably at least 95wt%, more typically at least 98wt%, more typically at least 99wt%. The heat sealable layer may also include any other conventional additives for making polymer films (particularly polyester films), as described above. In particular, the heat sealable layer preferably includes a slip agent or anti-blocking agent, such as a particle filler, which improves the handling of the film, as is conventional in the field of sealant coatings. This component is present in a relatively small amount, typically less than 5.0wt%, typically less than 2.0wt%, typically less than 1.0wt%.

[0047] The formation of the composite film can be achieved by conventional techniques known in the art. Conveniently, the formation of the substrate is achieved by extrusion according to the following procedure.

[0048] In summary, the process comprises the steps of extruding a molten polymer layer at a temperature in the range of about 275 to about 300° C., preferably about 290 to 295° C., quenching the extrudate, and orienting the quenched extrudate in at least one direction. The film may be uniaxially oriented, but is preferably biaxially oriented by stretching in two mutually perpendicular directions in the plane of the film to achieve a satisfactory combination of mechanical and physical properties. Orientation may be achieved by any process known in the art for producing oriented films, such as tubular or flat film processes. Biaxial orientation is achieved by stretching in two mutually perpendicular directions in the plane of the film to achieve a satisfactory combination of mechanical and physical properties. In a tubular process, simultaneous biaxial orientation may be achieved by extruding a thermoplastic polymer tube that is subsequently quenched, reheated, then expanded by internal gas pressure to induce transverse orientation, and withdrawn at a rate that will induce longitudinal orientation. Suitable simultaneous biaxial orientation processes are disclosed in EP-2108673-A and US-2009 / 0117362-A1 , the disclosures of which are incorporated herein by reference.

[0049] In a preferred flat film process, the film-forming polymer is extruded through a slot die and rapidly quenched on a cooled casting drum to ensure that the polymer is quenched to an amorphous state. Orientation is then achieved by stretching the quenched extrudate in at least one direction at a temperature above the glass transition temperature of the polyester. Continuous orientation can be achieved by stretching the flat quenched extrudate first in one direction (usually the longitudinal direction, i.e., the forward direction through the film stretcher) and then in the transverse direction. Forward stretching of the extrudate is conveniently achieved on a set of rotating rollers or between two pairs of nip rolls, followed by transverse stretching in a tentering apparatus.

[0050] Stretching is generally achieved so that the size of the oriented film is 2 to 5 times, more preferably 2.5 to 4.5 times, of its original size in the stretching direction or each stretching direction. More preferably, stretching is achieved so that the size of the oriented film is 3.0 to 3.3 times its original size in the forward stretching, and 3.3 to 3.9 times its original size in the lateral stretching. If orientation in only one direction is required, a larger stretch ratio (e.g., up to about 8 times) can be used. Stretching is conventionally performed at a temperature higher than the Tg of the polymer composition, preferably at least about 5°C higher than Tg, preferably at least about 15°C higher than Tg, and preferably in the range of about Tg+5°C to about Tg+75°C, preferably from large Tg+5°C to about Tg+30°C. Therefore, for polyester materials, stretching is generally achieved at a temperature in the range of about 5 to about 155°C, preferably about 5 to about 110°C. It is not necessary to stretch equally in the machine and in the transverse direction, although this is preferred if balanced properties are desired.

[0051] The stretched film can be and preferably is dimensionally stabilized by heat setting under dimensional support at a temperature above the glass transition temperature of the polymer but below its melting temperature to induce the desired crystallization of the polymer. During heat setting, a small amount of dimensional relaxation can be performed in the transverse direction (TD) by a method known as "toe-in". Toe-in can involve dimensional relaxation on the order of 2% to 4%. Dimensional relaxation in the process or machine direction (MD) is also possible, as known in the art. The actual heat setting temperature and time will vary depending on the composition of the film and its desired final thermal shrinkage, but should not be selected so as to significantly reduce the toughness (e.g., tear resistance) of the film. Within these constraints, the preferred film is heat set at about 80°C (i.e., T ) below the melting temperature of the film. M -80℃) to below T M About 10℃ (T M -10°C), preferably from about T M -70℃ to about T M -20°C. Thus, for polyester films, the heat setting temperature is suitably in the range of about 130 to about 245°C, preferably about 150 to about 245°C, and preferably at least 180°C, preferably in the range of 190 to 230°C. After heat setting, the film is typically rapidly quenched in order to induce the desired crystallinity of the polymer.

[0052] Preferably, the film is further stabilized by using an online relaxation stage. Alternatively, the relaxation process can be performed off-line. In this additional step, the film is heated at a temperature lower than that of the heat setting stage and has greatly reduced MD and TD tensions. The tension to which the film is subjected is a low tension and is typically less than 5 kg / m, preferably less than 3.5 kg / m, preferably less than 2.5 kg / m, and typically in the range of 1.0 to 2.0 kg / m of film width. For the relaxation process to control the film speed, the reduction in film speed (and therefore strain relaxation) is typically in the range of 0 to 2.5%, preferably 0.5% to 2.0%. During the heat stabilization step, the transverse dimension of the film is not increased. The temperature used for the heat stabilization step can vary depending on the combination of desired properties of the final film, with the higher the temperature, the better, i.e., the lower, residual shrinkage properties. Temperatures of 135 to 250° C. are typically desired, preferably 150-230° C., more preferably 170-200° C. The duration of heating depends on the temperature used, but is generally in the range of 10 to 40 seconds, with a duration of 20 to 30 seconds being preferred. This heat stabilization process can be performed by a variety of methods, including flat and vertical configurations, and "off-line" as a separate process step or "on-line" as a continuation of the film manufacturing process. Films so treated will exhibit less thermal shrinkage than films produced without this post-heat setting relaxation.

[0053] The formation of the composite film including heat sealable layer can be realized by conventional techniques. The method for forming heat sealable layer and its application on base layer usually depends on the characteristics of heat sealable layer. Conventional techniques include casting heat sealable layer onto preformed base layer. Conveniently, the formation of heat sealable layer and base layer is realized by coextrusion, which is particularly suitable for embodiments B1 and B2 described above. Other methods for forming heat sealable layer include coating heat sealable polymer onto base layer, and this technology will be particularly suitable for embodiments B3 and B4 described above. Any suitable coating technique can be used to realize coating, including gravure roller coating, reverse roller coating, dip coating, bead coating, extrusion coating, melt coating or electrostatic spraying. Preferred coating method is roller coating, including gravure roller coating and reverse roller coating. Coating can be carried out "off-line", that is, after any stretching and subsequent heat setting adopted during the manufacture of base layer, or "on-line", that is, wherein the coating step is carried out before, during or between any stretching operation adopted. Preferably, the coating is performed in-line, and preferably between the forward stretching and the lateral stretching of the biaxial stretching operation ("co-stretching" coating). Examples of coatings of heat sealable layers include: GB-2024715 and GB-1077813, which disclose co-stretching extrusion coating of polyolefins on polyolefin and polyester substrates, respectively; US-4333968, which discloses co-stretching extrusion coating of ethylene-vinyl acetate copolymers on polypropylene substrates; and WO-02 / 59186, which discloses coatings of copolyesters, the disclosures of which are incorporated herein by reference.

[0054] In a preferred embodiment, the polymer films A and B are selected from coextruded polymer films.

[0055] Polymer films A and B preferably exhibit a relative humidity of at least about 15 kg / mm ​​in each of the longitudinal and transverse directions of the film. 2 , preferably at least about 18 kg / mm 2 , preferably at least about 19 kg / mm 2 , preferably at least about 20 kg / mm 2 , preferably at least about 21 kg / mm 2 The ultimate tensile strength (UTS) of

[0056] Polymer films A and B preferably exhibit an elongation at break (ETB) of at least 110%, preferably at least 130%, preferably at least 150%, preferably at least 160%, preferably at least 170%, preferably at least 180%, preferably at least 190%, preferably at least 200% in each of the longitudinal and transverse directions of the film.

[0057] The polymer films A and B preferably exhibit low shrinkage within 30 minutes at 150° C., preferably less than 10%, preferably less than 5%, preferably less than 3%, preferably less than 2%, preferably less than 1%, in particular in the machine (longitudinal dimension) of the film. Preferably, such shrinkage values ​​are exhibited in both dimensions of the film, i.e. the longitudinal dimension and the transverse dimension.

[0058] It will be understood that the terms "longitudinal direction" and "transverse direction" of a film refer to the direction in which the film is stretched during its manufacture. The term "machine direction" is also used herein to refer to the longitudinal direction.

[0059] In the polymer film tube of the present invention, said longitudinal direction of the film is preferably aligned or substantially aligned with the longitudinal axis of the tube.

[0060] The chemical composition and / or physical properties (including, for example, dimensions, such as total thickness and layer thickness) of polymer film A may be the same or different from those of polymer film B. However, in a preferred embodiment, polymer films A and B have the same chemical composition as each other. In a preferred embodiment, polymer films A and B have different dimensions from each other, as described below.

[0061] Preferably, the polymer film A and the polymer film B are each selected from films having a total thickness of about 10 to about 500 μm, preferably about 10 to 300 μm.

[0062] Preferably, the thickness of polymer film A is less than the thickness of polymer film B, preferably not more than 75%, preferably not more than 50%, preferably not more than 30% of the thickness of polymer film B. Preferably, the thickness of polymer film A is at least 10%, preferably at least 20% of the thickness of polymer film B. Preferably, the thickness of polymer film A is in the range of 10% to 75%, preferably 20% to 50%, preferably 20% to 30% of the thickness of polymer film B. Preferably, the polymer film B has a thickness of 20 to 300, preferably 20 to 100 μm, and preferably, the polymer film A has a thickness of 10 to about 20 μm.

[0063] The thickness of the heat sealable layer preferably does not exceed 30%, more preferably does not exceed 25%, more preferably does not exceed 20%, preferably at least 2.5%, more preferably at least 5%, preferably about 10% to about 20% of the total thickness of the polymer film. Typically, the heat sealable layer has a thickness of up to about 25 μm, more preferably up to about 15 μm, more preferably up to about 10 μm, and preferably at least 2 μm, preferably in the range of about 0.5 to about 10 μm, more preferably about 2 to about 10 μm.

[0064] The planar dimensions of each of the polymer films A and B are described by a length and a width, wherein the length dimension of the polymer film corresponds to the length of the polymer tube. The lengths of the polymer films A and B are the same or substantially the same. The width dimension of each of the polymer films A and B is the transverse or cross-sectional dimension of the polymer tube. Preferably, the width of the polymer film B is greater than the width of the polymer film A.

[0065] In the tube of the present invention, the polymer films A and B are preferably arranged so that the first surface B1 of the polymer film B constitutes at least a major part of the outer surface of the tube. In this context, the term "at least a major part" means that the first surface B1 of the polymer film B constitutes at least 50%, preferably at least 65%, preferably at least 80%, preferably at least 90%, preferably at least 95%, preferably at least 99%, and preferably substantially all of the outer surface of the tube.

[0066] In the tube of the present invention, the heat-sealable surface B2 of the polymer film B constitutes at least a major part of the inner surface of the first channel of the tube, in particular in the first aspect of the present invention.

[0067] Therefore, in a preferred embodiment, the polymer film tube of the present invention is mainly formed by a polymer film B constituting the outer periphery of the tube, wherein the polymer film A is arranged on the inner surface of the tube, and wherein the inner polymer film A acts as an auxiliary film that bridges or connects the edges (Ba and Bb) of the polymer film B to form the tube. The polymer films A and B are arranged so that the heat-sealable surface A2 contacts the heat-sealable surface B2 to form a heat-seal bond at each edge (Ba and Bb) of the polymer film B. Therefore, the polymer film A is heat-sealed to the polymer film B so that the first width portion of the polymer film A extends beyond the edge Ba of the polymer film B, and the second width portion of the polymer film A extends beyond the edge Bb of the polymer film B to form a tube by two overlapping heat-seal bonds. It will be understood that each of the first width portion and the second width portion of the polymer film A is bounded at one end by the opposite edge of the polymer film A. It will also be understood that, at least in the first aspect of the present invention, the first width portion and the second width portion are located at opposite ends of the width of the polymer film A. Therefore, it is preferred that a first heat seal bond is formed between the heat sealable surfaces of the edge Ba adjacent to the film B and the edge Ab of the film A, and a second heat seal bond is formed between the heat sealable surface of the edge Bb adjacent to the film B and a portion of the heat sealable surface of the film A. In the first aspect of the present invention, the second heat seal bond is suitably formed between the heat sealable surfaces of the edge Bb adjacent to the film B and the edge Aa of the film A.

[0068] Thus, in the first aspect of the invention, two heat seal bonds (HSB1 and HSB2) are formed, preferably one at each edge (Ba and Bb) of the polymer film B, such that each heat seal bond extends in the longitudinal direction of the film and in the direction of the longitudinal axis of the tube. The heat seal bond at edge Ba is referred to herein as heat seal bond HSB1, and the heat seal bond at edge Bb is referred to herein as heat seal bond HSB2.

[0069] In the second aspect of the invention, a third heat seal bond (HSB3) is formed. The first two heat seal bonds (HSB1 and HSB2) correspond to those of the first aspect of the invention, i.e. preferably one at each edge (Ba and Bb) of the polymer film B, wherein each heat seal bond extends in the longitudinal direction of the film and in the direction of the longitudinal axis of the tube. In the second aspect of the invention, the overlap between the polymer films A and B is greater than in the first aspect and is sufficient to allow the formation of the second channel by forming a third heat seal bond also extending in the longitudinal direction of the tube.

[0070] Therefore, in the second aspect, a portion of the second heat-sealable surface A2 of the polymer film A and a portion of the second heat-sealable surface B2 of the polymer film B preferably constitute the inner surface of the second channel.

[0071] In the second aspect, the boundaries of the second channel are defined by the third heat seal bond (HSB3) between the heat seal surface of edge Aa adjacent to film A and a portion of the heat seal surface B2 between edges Ba and Bb, and by the second heat seal bond (HSB2) between the heat seal surface of edge Bb adjacent to film B and a portion of the heat seal surface A2 between edges Aa and Ab.

[0072] The relative size of polymer film A and B and the interval between the second heat seal bonding and the third heat seal bonding define the size (i.e. cross-sectional area) of the second channel. The relative size of the first channel and the second channel is not limited in the present invention. The size of the first channel and the second channel can be the same or different. The relative size of the first channel and the second channel can be determined by the relative amount and / or flow rate of the injectable chemicals required for the desired chemical reaction of the two-component injectable chemical system.

[0073] As mentioned above, the thickness of polymer film A is preferably less than polymer film B. Polymer film B is mainly responsible for giving the tube enough rigidity so that the tube can be positioned at its expected position, thus showing a relatively large thickness as described herein. Polymer film A is mainly responsible for linking the edge of polymer film B to form a tube, so it can show a relatively low thickness as described herein, and the main consideration is that the heat-sealable layer should be thick enough to achieve strong heat-seal bonding. Advantageously, polymer film A is easier to break than polymer film B, which is another function of its relatively low thickness, so that polymer film A can break at a predetermined position to deliver injectable chemicals or their mixtures at the predetermined position within the structure. This aspect of the present invention can be applied to each of the first aspect and the second aspect, but is particularly useful for the second aspect, thereby allowing the first injectable chemical in the first channel and the second injectable chemical in the second channel to mix at a predetermined distance along the tube. The rupture of the polymer film can be achieved by any suitable means, such as a drill bit.

[0074] The size and cross-sectional area of ​​the polymer film tubes disclosed herein are not particularly limited and will depend on the end use of the tube. However, preferably, the tube has such a size that the width of the cross section is from about 1 cm to about 500 cm, or the cross-sectional area is 0.5 cm 2 Up to 20m 2 .

[0075] The width of the overlapping heat seal bond, i.e., the degree to which polymer film A overlaps polymer film B in the process of producing the heat seal bond to form the tube, will depend primarily on the cross-sectional dimensions of the tube, and also on the thickness of the corresponding polymer film and its heat seal layer. It will be appreciated that the width of the overlapping heat seal bond is a factor in regulating the strength of the heat seal bond. Preferably, the polymer film A and the polymer film B overlap by at least 1 mm to form the overlapping heat seal bond. For example, a tube has a cross-sectional width of up to about 10 cm, and the overlapping heat seal bond suitably has a width in the range of about 1 mm to about 10 mm. The width of the overlapping heat seal bond will generally increase with an increase in the cross-sectional width of the tube.

[0076] The length of the tube may be any suitable length required to deliver the injectable chemical to the desired location. Thus, the length of the tube may be as small as 10 cm or as high as several meters, for example 2 m.

[0077] It will be appreciated that the invention is not limited to tubes having one or two channels and that a third channel or even subsequent channels may also be provided, for example by using additional heat seal bonds in a dual film system as described above, or by using more than two films. Thus, by forming an additional heat seal bond between the second heat seal bond and the third heat seal bond, an additional channel may be formed within the channel interval between the second heat seal bond and the third heat seal bond. Typically, however, the tube comprises no more than two channels and is formed from two polymer films.

[0078] The formation of a heat seal bond between polymer films A and B to form a tube is described below.

[0079] The heat seal bond strength between the heat sealable surfaces of polymer films A and B is preferably at least 50 g / mm (preferably at least 70 g / mm), measured as described herein.

[0080] According to a third aspect of the present invention, there is provided a kit comprising a first heat-sealable polymer film A and a second heat-sealable polymer film B, wherein the kit is suitable for forming a tube comprising a first channel extending along the longitudinal axis of the tube, wherein:

[0081] (i) the tube is composed of a first heat-sealable polymer film A and a second heat-sealable polymer film B,

[0082] (ii) the polymer film A has a first surface A1 and a second heat-sealable surface A2,

[0083] (iii) the polymer film B has a first surface B1 and a second heat-sealable surface B2,

[0084] (iv) the polymer film A comprises edges Aa and Ab, and the polymer film B comprises edges Ba and Bb, wherein the edges Aa, Ab, Ba and Bb extend along the longitudinal axis of the tube

[0085] (v) the polymer films A and B are arranged so that the heat-sealable surfaces A2 and B2 are in contact and adhered to each other by a heat-seal bond which does not extend over the entire surface area of ​​at least one of the heat-sealable surfaces A2 and B2, and

[0086] (vi) Polymer Film A is adhered to Polymer Film B by overlapping first and second heat seal bonds (HSB1 and HSB2) to define the tube and its first channel.

[0087] According to a fourth aspect of the present invention, there is provided a kit comprising a first heat-sealable polymer film A and a second heat-sealable polymer film B, wherein the kit is suitable for forming a tube comprising a first channel and a second channel, wherein each of the first channel and the second channel extends along a longitudinal axis of the tube, wherein:

[0088] (i) the tube is composed of the first heat-sealable polymer film A and the second heat-sealable polymer film B,

[0089] (ii) the polymer film A has a first surface A1 and a second heat-sealable surface A2,

[0090] (iii) the polymer film B has a first surface B1 and a second heat-sealable surface B2,

[0091] (iv) the polymer film A comprises edges Aa and Ab, and the polymer film B comprises edges Ba and Bb, wherein the edges Aa, Ab, Ba and Bb extend along the longitudinal axis of the tube,

[0092] (v) the polymer films A and B are arranged so that the heat-sealable surfaces A2 and B2 are in contact and adhered to each other by a heat-seal bond which does not extend over the entire surface area of ​​the heat-sealable surfaces A2 and B2,

[0093] (vi) polymer film A is adhered to polymer film B by overlapping first and second heat seal bonds (HSB1 and HSB2) to define said tube and said first channel thereof, and

[0094] (vii) polymer film A is further adhered to polymer film B by a third heat seal bond (HSB3) between said heat sealable surfaces A2 and B2 such that said third heat seal bond defines a second channel comprising a first wall and a second wall extending along the longitudinal axis of said tube.

[0095] According to a fifth aspect of the present invention, there is provided a method of forming a tube of polymer film, wherein the tube comprises a first channel extending along a longitudinal axis of the tube, the method comprising the steps of:

[0096] (a) providing a first heat-sealable polymer film A and a second heat-sealable polymer film B, wherein the polymer film A has a first surface A1 and a second heat-sealable surface A2, and the polymer film B has a first surface B1 and a second heat-sealable surface B2, wherein the polymer film A includes edges Aa and Ab, and the polymer film B includes edges Ba and Bb,

[0097] (b) arranging the polymer films A and B so that the heat-sealable surfaces A2 and B2 are in contact with each other and adhering the polymer film A to the polymer film B by a heat-seal bond that does not extend over the entire surface area of ​​at least one of the heat-sealable surfaces A2 and B2 so that overlapping first and second heat-seal bonds are formed to define the tube and its first channel, and

[0098] Therein, the polymer films A and B are arranged such that the edges Aa, Ab, Ba and Bb extend along the longitudinal axis of the tube.

[0099] According to a sixth aspect of the present invention, there is provided a method of forming a tube of a polymer film, wherein the tube comprises a first channel and a second channel, wherein each of the first channel and the second channel extends along a longitudinal axis of the tube, the method comprising the following steps:

[0100] (a) providing a first heat-sealable polymer film A and a second heat-sealable polymer film B, wherein the polymer film A has a first surface A1 and a second heat-sealable surface A2, and the polymer film B has a first surface B1 and a second heat-sealable surface B2, wherein the polymer film A includes edges Aa and Ab, and the polymer film B includes edges Ba and Bb,

[0101] (b) arranging the polymer films A and B so that the heat-sealable surfaces A2 and B2 are in contact with each other and adhering the polymer film A to the polymer film B by a heat-seal bond which does not extend across the entire surface area of ​​each of the heat-sealable surfaces A2 and B2 such that:

[0102] (i) forming overlapping first and second heat seal bonds to define said tube and said first passageway thereof, and

[0103] (ii) forming a third heat seal bond between the heat sealable surfaces A2 and B2 such that the third heat seal bond defines a second channel including a first wall and a second wall extending along the longitudinal axis of the tube,

[0104] Therein, the polymer films A and B are arranged such that the edges Aa, Ab, Ba and Bb extend along the longitudinal axis of the tube.

[0105] In the fifth and sixth aspects of the invention, the heat seal bond is preferably formed by applying temperature and pressure, preferably at a temperature not exceeding 200° C. (preferably in the range of 100 to 200° C.) and a pressure not exceeding 100 psi (preferably in the range of 10 to 60 psi) for a time not exceeding one minute (preferably in the range of 0.5 to 30 seconds). It will be understood that the heat seal bond is only required at certain predetermined locations around the circumference of the tube. Suitable heat sealing equipment is readily available commercially, for example from Sentinel. The assembly is placed in a heat sealer, and heat and pressure are applied at multiple isolated locations to form the above-mentioned heat seal bond.

[0106] In order to avoid forming a heat seal bond between the heat sealable surface of polymer film B and the first surface of polymer film A in the first channel, a removable release sheet is preferably provided between the heat sealable surface of polymer film B and the first surface of polymer film A in the channel before applying heat and pressure. After the heat sealing operation, the release sheet is removed from the tube. The present invention can utilize any suitable release sheet that is not heat sealable to the heat sealable surface and the first surface of the polymer film described herein under the conditions of heat and pressure used to form the heat seal bond. For example, suitable wax or silicone release papers or films known in the art can be used.

[0107] According to a seventh aspect of the present invention, there is provided a method for delivering one or more injectable chemicals to a predetermined location within a structure, the method comprising the following steps:

[0108] (a) providing a tube having a first channel extending along the longitudinal axis of the tube, wherein the tube is composed of a first heat-sealable polymer film A and a second heat-sealable polymer film B as defined herein,

[0109] (b) directing a first fluid flow including the injectable chemical along the first channel to the predetermined location.

[0110] According to an eighth aspect of the present invention, there is provided a method for delivering a plurality of injectable chemicals to predetermined locations within a structure, the method comprising the steps of:

[0111] a) providing a tube having a first channel and a second channel extending along the longitudinal axis of the tube, wherein the tube is composed of a first heat-sealable polymer film A and a second heat-sealable polymer film B as defined herein,

[0112] (b) directing a first fluid flow including a first injectable chemical along the first passage to the predetermined location,

[0113] (c) directing a second fluid flow including a second injectable chemical along the second passage to the predetermined location,

[0114] (d) mixing the first stream and the second stream at the predetermined location.

[0115] The method of the eighth aspect preferably also includes the following steps: rupturing the first heat-sealable polymer film A at the predetermined position so that the second fluid flow in the second channel mixes with the first fluid flow in the first channel, thereby causing a chemical reaction between the first injectable chemical and the second injectable chemical.

[0116] It will be understood that the disclosures and preferences described for the first and second aspects of the invention also apply to the third to eighth aspects of the invention. It will be understood that the second aspect of the invention corresponds in particular to the fourth, sixth and eighth aspects of the invention.

[0117] The present invention is particularly useful for delivering injectable chemicals in mining and construction projects. The polymer pipes of the present invention can be used to deliver injectable chemicals to strengthen the walls of boreholes (e.g., boreholes in mining operations), pipelines, shafts, or tunnels; or to anchor, reinforce, and control gas, water, and formations in underground locations, such as reinforcing fractured formations and / or preventing water ingress. The polymer pipes of the present invention can also be used to deliver injectable chemicals in renovation and construction projects, such as for repairing or filling cavities or cracks in structures. As described above, a variety of injectable chemicals are used for this purpose, including polyurethane, silicate, and phenolic-based resin systems.

[0118] As described below, the present invention is further explained with reference to the accompanying drawings.

[0119] Figure 1 A polymer film A having a first surface A1 and a second heat-sealable surface A2 and edges Aa and Ab, and a polymer film B having a first surface B1 and a second heat-sealable surface B2 and edges Ba and Bb are shown in cross section, wherein polymer film A is adhered to polymer film B by overlapping heat seal bonds HSB2. Heat sealing is achieved by curling the film assembly along a dotted line X, so that a further heat seal bond (HSB1; not shown) is achieved between the heat sealable surfaces of polymer films A and B at the location of the arrow on the dotted line X, thereby forming a tube with a first channel. The heat seal bonds HSB1 and HSB2 are achieved along the length of films A and B (i.e., in a direction perpendicular to the cross section).

[0120] Figure 2 Shown is the tube (1) after forming the heat seal bond HSB1 to form the first channel (2). Figure 1 membrane components.

[0121] Figure 3A polymer film A having a first surface A1 and a second heat-sealable surface A2 and edges Aa and Ab, and a polymer film B having a first surface B1 and a second heat-sealable surface B2 and edges Ba and Bb are shown in cross section, wherein polymer film A is adhered to polymer film B by overlapping heat seal bonds HSB2 and another heat seal bond HSB3. The heat seal bonds HSB2 and HSB3 extend along the length of the films A and B (i.e., in a direction perpendicular to the cross section) and define a second channel (3) extending in the longitudinal direction of the tube. Heat sealing is achieved by curling the film assembly along the dotted line X so that at the position of the arrow on the dotted line X, a further heat seal bond (HSB1; not shown) is achieved between the heat-sealable surfaces of the polymer films A and B, thereby forming a tube having a first channel therein. The heat seal bonds HSB1, HSB2 and HSB3 are achieved along the length of the films A and B (i.e., in a direction perpendicular to the cross section).

[0122] Figure 4 The heat seal bond HSB1 is shown after forming a tube (1) comprising a first channel (2) and a second channel (3). Figure 2 membrane components.

[0123] Figure 5 A device for making a tube with a single channel as described herein is shown in cross section. Polymer film A has a base layer (10) providing the first surface A1 and a heat sealable layer (11) providing the heat sealable surface A2. Polymer film B has a base layer (12) providing the first surface B1 and a heat sealable layer (13) providing the heat sealable surface B2. A removable peeling sheet (14) is provided in the channel (2) to avoid forming a heat seal bond between the heat sealable layer (13) of polymer film B and the base layer (10) of polymer film A. The assembly is placed in a heat sealer, and heat and pressure are applied at multiple isolated positions (15). After the heat sealing operation, the peeling sheet is removed from the tube.

[0124] Figure 6 A corresponding device for producing a tube with two channels is shown. DETAILED DESCRIPTION

[0125] Property Measurement

[0126] The following test methods can be used to characterize polymer films:

[0127] (i) The intrinsic viscosity of polyesters and polyester substrates (in dL / g) was measured by solution viscometry according to ASTM D5225-98 (2003) on a Viscotek™ Y-501C relative viscometer (see, e.g., Hitchcock, Hammons and Yau, "Double Capillary Method for Modern Viscometry" in American Laboratory (August 1994)) by using a 0.5 wt% solution of the polyester in o-chlorophenol at 25°C and calculating the intrinsic viscosity using the Billmeyer single point method:

[0128] η=0.25ηred+0.75(lnηrel) / c

[0129] in:

[0130] η = intrinsic viscosity (in dL / g),

[0131] ηrel=relative viscosity,

[0132] c = concentration (in g / dL), and

[0133] ηred = reduced viscosity (in dL / g), which is equal to (ηrel-1) / c (also expressed as ηsp / c, where ηsp is the specific viscosity).

[0134] (ii) Ultimate tensile strength (UTS), elongation at break (ETB) and F5 value (stress at 5% elongation) were measured according to test method ASTM D882-18. Five strips (100 mm long) of the film were cut along the machine direction using a ruler and a calibrated sample cutter (10 mm +\- 0.5 mm). Each sample was tested using an Instron 3111 material testing machine using pneumatic grips with rubber jaws. The temperature (23°C) and relative humidity (50%) were controlled. The crosshead speed (separation rate) was 25 mm / min. The strain rate was 50%. Elongation at break ) is defined as:

[0135]

[0136] Where L 0 is the original length of the specimen between the clamps.

[0137] (iii) Thermal shrinkage is evaluated for film samples of size 200 mm x 10 mm cut and marked for visual measurement in a specific direction relative to the machine and transverse directions of the film. The longer dimension of the sample (i.e., the 200 mm dimension) corresponds to the film direction for testing shrinkage, i.e., in order to evaluate shrinkage in the machine direction, the 200 mm sized test sample is oriented along the machine direction of the film. After the sample is heated to a predetermined temperature of 150°C (by being placed in a heating oven at that temperature) and maintained for an interval of 30 minutes, it is cooled to room temperature and its dimensions are manually remeasured. Thermal shrinkage is calculated and expressed as a percentage of the original length.

[0138] (iv) Glass transition temperature (T g ) and crystalline melting point (T m ) was measured by differential scanning calorimetry (DSC) using a PerkinElmer HyperDSC 8500. Unless otherwise stated, measurements were performed according to the following standard test methods and based on the method described in ASTM E1356-98. The samples were kept under a dry nitrogen atmosphere during scanning. A 20 ml min -1 The sample (5 mg) was heated from 20°C to 350°C at 20°C / min.

[0139] T g The value of T is determined as the extrapolated onset temperature of the glass transition observed on a DSC scan (heat flow (W / g) versus temperature (°C)) as described in ASTM E1356-98. m The value of is determined from the DSC scan as the peak endotherm of the transition.

[0140] (v) Crystallinity was measured from the above DSC analysis as the crystallinity (X) calculated according to the following equation: c ):

[0141] X c =ΔH m / ΔH m °

[0142] in:

[0143] ΔH m = experimental melting enthalpy calculated from the integration of the melting endotherm;

[0144] ΔH m ° = The theoretical melting enthalpy of the corresponding poly(alkylene-carboxylate) homopolymer at 100% crystallinity. Thus, for PET (or PET-based) polyesters, ΔH m °is the theoretical melting enthalpy of 100% crystalline PET polymer (140 J / g), and for PEN (or PEN-based) polyesters, ΔH m ° is the theoretical melting enthalpy of a 100% crystalline PEN polymer (103 J / g), as defined in the literature (B. Wunderlich, Polymer Physics, Academic Press, New York, (1976)).

[0145] (vi) The heat seal strength of polymer film A to polymer film B was measured at ambient temperature (23°C ± 2°C) by the following procedure. The samples of the two films were placed together so that their heat sealable surfaces were in contact and subjected to a temperature of 150°C for 1 second under a pressure of 60psi. The sealed film assembly was cooled to room temperature and the sealed composite material was cut into 25mm wide strips. The heat seal strength was determined using an Instron Model 4301 by measuring the force required to peel off the layers of the film at a constant speed of 4.23mm / s under linear tension per unit seal width. The process was repeated and the average of 5 results was calculated.

[0146] The present invention is further illustrated by the following examples. It will be understood that these examples are for illustrative purposes only and are not intended to limit the present invention as described above. Modifications of detail may be made without departing from the scope of the present invention.

[0147] Examples

[0148] Example 1 (single internal channel)

[0149] The polymer composition (PET) was coextruded with a heat sealable copolyester derived from terephthalic acid, isophthalic acid and ethylene glycol (TA / IPA / EG in a molar ratio of 82 / 18 / 100) and cast onto a water-cooled rotating quenching drum to obtain an amorphous cast extrudate. The cast extrudate was heated to a temperature in the range of about 50 to 80°C and stretched to about 3 times its original size in the extrusion direction. The film was fed into a tenter oven at a temperature of 100°C where it was stretched to about 3 times its original size in the lateral direction. The biaxially stretched film was heat set in a 3-stage crystallizer at a temperature of 210°C to 230°C by conventional means. The total film thickness of the final film was 50 μm; the heat sealable layer was about 10 μm thick. This is polymer film B.

[0150] Using the same materials, a coextruded biaxially oriented polymer film A was prepared essentially according to the above procedure, except that the total film thickness was 30 μm, wherein the heat sealable layer was 5 μm thick.

[0151] Pieces measuring 30 cm (length) x 3 cm (width) were cut from polymer film A such that the length direction was aligned with the longitudinal (machine) axis of the film. Pieces measuring 30 cm (length) x 25 cm (width) were cut from polymer film B such that the length direction was aligned with the longitudinal (machine) axis of the film.

[0152] Polymer sheets A and B were aligned substantially parallel, overlapped by approximately 1 cm along the first long edge of each sheet (Aa and Bb), and heat sealed by subjecting the overlapped area to a temperature of 150° C. for 1 second at a pressure of 60 psi, thereby forming a heat seal bond referred to herein as HSB2. The film assembly was rolled onto itself into a circle so that the second long edge of each sheet (Ab and Ba) overlapped by approximately 1 cm, thereby forming a heat seal bond referred to herein as HSB1. The tube had an inner diameter of approximately 8 cm and exhibited a single internal channel.

[0153] Example 2 (two internal channels)

[0154] Polymer sheets A and B were prepared as described in Example 1, except that the width of polymer sheet A was 12 cm.

[0155] Sheets A and B are aligned substantially parallel, overlapping about 10 cm along the first long edge of each film, and a heat seal bond is achieved by subjecting the area near the first long edge (Bb) of sheet B to the above-mentioned heat seal conditions, thereby forming a heat seal bond referred to herein as HSB2. A further heat seal bond is achieved by subjecting the area near the first long edge (Aa) of sheet A to the same heat seal conditions so that it forms a heat seal bond with heat seal surface B2 at a position between edges Bb and Ba, thereby forming a heat seal bond referred to herein as HSB3. The film assembly is curled into a circle on itself so that each of the second long edges (Ab and Ba) of sheets A and B overlap by about 1 cm, thereby forming a heat seal bond referred to herein as HSB1. The tube has an internal diameter of about 8 cm and exhibits two internal channels.

[0156] The heat seal bond in the above example exhibited a heat seal bond strength of 71 g / mm, measured as described herein.

[0157] In each instance, Figure 5 and Figure 6 As shown, the heat sealing step was performed in a Sentinel heat sealer operating at 150°C, 60 psi, and 1 second using wax release paper located in the internal channel.

Claims

1. A tube comprising a first channel and a second channel, in, Each of the first channel and the second channel extends along a longitudinal axis of the tube, and wherein: (i) the tube is composed of a first heat-sealable polymer film A and a second heat-sealable polymer film B, (ii) the polymer film A has a first surface A1 and a second heat-sealable surface A2, (iii) the polymer film B has a first surface B1 and a second heat-sealable surface B2, (iv) the polymer film A comprises edges Aa and Ab, and the polymer film B comprises edges Ba and Bb, wherein the edges Aa, Ab, Ba and Bb extend along the longitudinal axis of the tube, (v) the polymer films A and B are arranged so that the second heat-sealable surfaces A2 and B2 are in contact and adhered to each other by a heat-seal bond, the heat-seal bond not extending over the entire surface area of ​​the second heat-sealable surfaces A2 and B2, (vi) polymer film A is adhered to polymer film B by overlapping first heat seal bonds (HSB1) and second heat seal bonds (HSB2) to define said tube and said first channel thereof, and (vii) polymer film A is further adhered to polymer film B by a third heat seal bond (HSB3) between said second heat sealable surfaces A2 and B2, such that said third heat seal bond defines a second channel comprising a first wall and a second wall extending along the longitudinal axis of said tube, Wherein, the second channel is defined by the third heat seal bond (HSB3) between the heat seal surface of the edge Aa adjacent to the polymer film A and a portion of the second heat seal surface B2 between the edges Ba and Bb, and by the second heat seal bond (HSB2) between the heat seal surface of the edge Bb adjacent to the polymer film B and a portion of the second heat seal surface A2 between the edges Aa and Ab.

2. The tube according to claim 1, in, The first surface A1 of the polymer film A and the first surface B1 of the polymer film B are not heat-sealable.

3. The tube according to claim 1 or 2, in, The polymer film A and the polymer film B are each selected from films including a base layer and a heat-sealable layer.

4. The tube according to claim 3, in, The base layer is a polyester including an aromatic dicarboxylic acid and an aliphatic diol.

5. The tube according to claim 3, in, The heat sealable layer is a copolyester derived from at least 3 monomer repeating units, at least one of the monomer repeating units is an aromatic dicarboxylic acid, and at least one of the monomer repeating units is an aliphatic diol.

6. The tube according to claim 5, in, The copolyester is derived from terephthalic acid, a second aromatic dicarboxylic acid, and ethylene glycol.

7. The tube according to claim 5, in, The copolyester is derived from terephthalic acid, ethylene glycol, and a second glycol.

8. The tube according to claim 5, in, The copolyester is derived from terephthalic acid, ethylene glycol, and a second dicarboxylic acid.

9. The tube according to claim 3, in, The heat-sealable layer is formed of ethylene-vinyl acetate copolymer.

10. The tube according to claim 1 or 2, in, The polymer film A and the polymer film B are each selected from biaxially oriented polymer films.

11. The tube according to claim 1 or 2, in, The polymer film A and the polymer film B are each selected from coextruded polymer films.

12. The tube according to claim 1 or 2, in, The tube has a cross-sectional width of 1 cm to 500 cm.

13. The tube according to claim 1 or 2, in, The polymer film A and the polymer film B overlap by at least 1 mm to form an overlapping heat seal bond.

14. The tube according to claim 1 or 2, in, The polymer film A and the polymer film B are each selected from films having a thickness of 10 to 500 μm.

15. The tube according to claim 1 or 2, in, The width of the polymer film B is greater than the width of the polymer film A.

16. The tube according to claim 1 or 2, in, The first surface B1 of the polymer film B constitutes at least a major part of the outer surface of the tube.

17. The tube according to claim 1 or 2, in, The second heat-sealable surface B2 of the polymer film B constitutes at least a major part of the inner surface of the first channel of the tube.

18. The tube according to claim 1 or 2, in, A portion of the second heat-sealable surface A2 of the polymer film A and a portion of the second heat-sealable surface B2 of the polymer film B constitute an inner surface of the second channel of the tube.

19. The tube according to claim 4, in, The polyester is polyethylene terephthalate.

20. The tube according to claim 6, in, The second aromatic dicarboxylic acid is isophthalic acid.

21. The tube according to claim 7, in, The second diol is selected from cycloaliphatic diols.

22. The tube according to claim 21, in, The second diol is 1,4-cyclohexanedimethanol.

23. The tube according to claim 8, in, The second dicarboxylic acid is selected from aliphatic dicarboxylic acids.

24. The tube according to claim 23, in, The second dicarboxylic acid is azelaic acid.

25. The tube according to claim 9, in, The ethylene-vinyl acetate copolymer has a vinyl acetate content in the range of 9% to 40%.

26. The tube according to claim 25, in, The ethylene-vinyl acetate copolymer has a vinyl acetate content in the range of 15% to 30%.

27. The tube according to claim 14, in, The polymer film B has a thickness of 20 to 300 μm.

28. The tube according to claim 27, in, The polymer film B has a thickness of 20 to 100 μm.

29. The tube according to claim 14, in, The polymer film A has a thickness of 10 to 20 μm.

30. The tube according to claim 1 or 2, in, The tube is suitable for delivering two-component injectable chemical systems, where the two components need to be kept separate until their point of application, where the components are brought into contact to undergo a chemical reaction to provide the desired compound at a predetermined location.

31. The tube according to claim 30, in, The injectable chemical system comprises or consists of a two-component polyurethane or silicate resin system.

32. A kit comprising a first heat-sealable polymer film A and a second heat-sealable polymer film B, in, The kit is suitable for forming a tube according to any one of claims 1 to 31 comprising a first channel and a second channel, wherein each of the first channel and the second channel extends along a longitudinal axis of the tube, wherein: (i) the tube is composed of the first heat-sealable polymer film A and the second heat-sealable polymer film B, (ii) the polymer film A has a first surface A1 and a second heat-sealable surface A2, (iii) the polymer film B has a first surface B1 and a second heat-sealable surface B2, (iv) the polymer film A comprises edges Aa and Ab, and the polymer film B comprises edges Ba and Bb, wherein the edges Aa, Ab, Ba and Bb extend along the longitudinal axis of the tube, (v) the polymer films A and B are arranged so that the second heat-sealable surfaces A2 and B2 are in contact and adhered to each other by a heat-seal bond, the heat-seal bond not extending over the entire surface area of ​​the second heat-sealable surfaces A2 and B2, (vi) polymer film A is adhered to polymer film B by overlapping first heat seal bonds (HSB1) and second heat seal bonds (HSB2) to define said tube and said first channel thereof, and (vii) polymer film A is further adhered to polymer film B by a third heat seal bond (HSB3) between said second heat sealable surfaces A2 and B2, such that said third heat seal bond defines a second channel comprising a first wall and a second wall extending along the longitudinal axis of said tube, Wherein, the second channel is defined by the third heat seal bond (HSB3) between the heat seal surface of the edge Aa adjacent to the polymer film A and a portion of the second heat seal surface B2 between the edges Ba and Bb, and by the second heat seal bond (HSB2) between the heat seal surface of the edge Bb adjacent to the polymer film B and a portion of the second heat seal surface A2 between the edges Aa and Ab.

33. The kit according to claim 32, in, The tube is suitable for delivering two-component injectable chemical systems, where the two components need to be kept separate until their point of application, where the components are brought into contact to undergo a chemical reaction to provide the desired compound at a predetermined location.

34. The kit according to claim 33, in, The injectable chemical system comprises or consists of a two-component polyurethane or silicate resin system.

35. A method of forming a tube according to any one of claims 1 to 31, in, The tube comprises a first channel and a second channel, wherein each of the first channel and the second channel extends along a longitudinal axis of the tube, the method comprising the steps of: (a) providing a first heat-sealable polymer film A and a second heat-sealable polymer film B, wherein the polymer film A has a first surface A1 and a second heat-sealable surface A2, and the polymer film B has a first surface B1 and a second heat-sealable surface B2, wherein the polymer film A includes edges Aa and Ab, and the polymer film B includes edges Ba and Bb, (b) arranging the polymer films A and B so that the second heat-sealable surfaces A2 and B2 are in contact with each other and adhering the polymer film A to the polymer film B by a heat-seal bond which does not extend over the entire surface area of ​​each of the second heat-sealable surfaces A2 and B2 such that: (i) forming overlapping first and second heat seal bonds to define said tube and said first channel thereof, and (ii) forming a third heat seal bond between the second heat sealable surfaces A2 and B2 such that the third heat seal bond defines a second channel comprising a first wall and a second wall extending along the longitudinal axis of the tube, wherein the polymer films A and B are arranged such that the edges Aa, Ab, Ba and Bb extend along the longitudinal axis of the tube, Wherein, the second channel is defined by the third heat seal bond (HSB3) between the heat seal surface of the edge Aa adjacent to the polymer film A and a portion of the second heat seal surface B2 between the edges Ba and Bb, and by the second heat seal bond (HSB2) between the heat seal surface of the edge Bb adjacent to the polymer film B and a portion of the second heat seal surface A2 between the edges Aa and Ab.

36. The method according to claim 35, in, The heat seal bond is formed by the application of temperature and pressure.

37. The method according to claim 35 or 36, in, Before applying heat and pressure, a removable release sheet is disposed between the heat-sealable surface of polymer film B and the first surface of polymer film A to prevent a heat seal bond from forming between the heat-sealable surface of polymer film B and the first surface of polymer film A.

38. A method of delivering one or more injectable chemicals to a predetermined location within a structure, the method The following steps are involved: (a) providing a tube having a first channel and a second channel extending along a longitudinal axis of the tube, wherein (i) the tube is composed of a first heat-sealable polymer film A and a second heat-sealable polymer film B, (ii) the polymer film A has a first surface A1 and a second heat-sealable surface A2, (iii) the polymer film B has a first surface B1 and a second heat-sealable surface B2, (iv) the polymer film A comprises edges Aa and Ab, and the polymer film B comprises edges Ba and Bb, wherein the edges Aa, Ab, Ba and Bb extend along the longitudinal axis of the tube, (v) the polymer films A and B are arranged so that the second heat-sealable surfaces A2 and B2 are in contact and adhered to each other by a heat-seal bond, the heat-seal bond not extending over the entire surface area of ​​at least one of the second heat-sealable surfaces A2 and B2, and (vi) polymer film A is adhered to polymer film B by overlapping first heat seal bonds (HSB1) and second heat seal bonds (HSB2) to define said tube and said first channel thereof, and (b) directing a first fluid flow including the injectable chemical along the first channel to the predetermined location, Wherein, the second channel is defined by a third heat seal bond (HSB3) between a heat sealable surface adjacent to edge Aa of polymer film A and a portion of the second heat sealable surface B2 between edges Ba and Bb, and by the second heat seal bond (HSB2) between a heat sealable surface adjacent to edge Bb of polymer film B and a portion of the heat sealable surface A2 between edges Aa and Ab.

39. The method according to claim 38, in, The tube is a tube according to any one of claims 1 to 31.

40. The method of claim 38 for delivering a plurality of injectable chemicals to predetermined locations within a structure, said method The following steps are involved: a) providing a tube according to any one of claims 1 to 31, the tube having a first channel and a second channel extending along the longitudinal axis of the tube, wherein the tube is composed of a first heat-sealable polymer film A and a second heat-sealable polymer film B, (b) directing a first fluid flow including a first injectable chemical along the first channel to the predetermined location, (c) directing a second fluid flow including a second injectable chemical along the second passage to the predetermined location, (d) mixing the first flow and the second flow at the predetermined location.

41. The method according to claim 40, further comprising: The following steps are involved: The first heat-sealable polymer film A is ruptured at the predetermined position so that the second fluid flow in the second channel is mixed with the first fluid flow in the first channel, thereby causing a chemical reaction between the first injectable chemical and the second injectable chemical.

42. A method according to any one of claims 38 to 41 for delivering one or more injectable chemicals in mining and construction applications.

43. The method according to claim 42, in, The mining and construction applications are selected from: delivering injectable chemicals to strengthen the walls of a borehole, pipeline, shaft or tunnel; delivering injectable chemicals to anchor, consolidate or control gas, water and formations in underground locations, including strengthening fractured formations and / or preventing water ingress; and delivering injectable chemicals in renovation and construction projects, including repairing or filling cavities or cracks in structures.

44. The method according to any one of claims 38 to 41, in, The injectable chemical is delivered to a predetermined location in a borehole of a mining operation.

45. The method according to any one of claims 38 to 41, in, The tube is suitable for delivering two-component injectable chemical systems, where the two components need to be kept separate until their point of application, where the components are brought into contact to undergo a chemical reaction to provide the desired compound at a predetermined location.

46. ​​The method according to claim 45, in, The injectable chemical system comprises or consists of a two-component polyurethane or silicate resin system.

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