Gamma-stable reinforced pump tubing.

Abstract

To obtain pump tubing that is stable to gamma ray sterilization. [Solution] A composite tube is disclosed having at least one porous polyethylene layer imbibed with at least one elastomer to form a composite layer having a modulus of less than 40 MPa and a first melting peak temperature of less than 135°C. The at least one elastomer is at least partially imbibed along the thickness of the porous polyethylene layer. The porous polyethylene layer may comprise expanded polyethylene (ePe) or expanded ultra-high molecular weight polyethylene (eUHMWPE). In some embodiments, the at least one elastomer forms a coating on the polyethylene layer. The composite tube may have a volume fraction of about 1% to about 20% and a modulus of about 1 MPa to about 40 MPa. Gamma-sterilized polymer composite tubes may have an average pump life of about 80 hours to about 5,000 hours. In some embodiments, the composite tube may include a reinforcing film.

Description

[Technical Field]

[0001] This disclosure relates generally to pump tubing. More specifically, this disclosure relates to sterilized composite pump tubing comprising polyethylene reinforced elastomers. [Background technology]

[0002] Silicone elastomers can be processed into a variety of forms suitable for use in the medical, electrical, and chemical industries. For example, products such as peristaltic pump tubing, pump diaphragms, bellows, baby bottle nipples, wire and cable sheathing, gaskets, and even O-rings are commonly made from silicone elastomers. Furthermore, many of these products are used in applications requiring repeated flexing. For example, peristaltic pumps transport liquids or pastes through elastomeric tubing, compressing the tubing between a set of rotating rollers and a stationary pump housing. Silicone elastomers are often used for peristaltic pump tubing. However, repeated flexing can cause cracks in the sidewalls of silicone rubber tubing, leading to catastrophic fracture or loss of resilience, resulting in reduced flow rates. This problem is exacerbated when pumping fluids under pressure or at elevated temperatures, further shortening the pump tubing's lifespan.

[0003] Silicones are an inherently flexible polymer, with repeating organosilicon-oxygen units that offer little resistance to bond rotation. Therefore, silicones have excellent low-temperature properties. However, silicones have poor inter- and intramolecular polymer interactions, resulting in low tear strength and toughness. As a result, silicone elastomers are often reinforced with either inorganic particulate fillers or soluble silicone resin fillers. For example, inorganic fillers such as fumed silica have been known to increase the tensile strength of dimethylsilicone by a factor of 10. Some silicone elastomers are limited in tensile strength to approximately 1,300 psi (ASTM D-412) and tear strength to 250 ppi (ASTM D-624 die B). Natural rubber, on the other hand, has significantly better tensile and tear properties, but lacks many of the useful properties of silicone elastomers, such as low-temperature flexibility, low dielectric loss, ozone resistance, low extractables, and radiation resistance. Summary of the Invention [Problem to be solved by the invention]

[0004] Traditionally, silicone has been reinforced with polymers such as polytetrafluoroethylene (PTFE) or expanded PTFE (ePTFE) to improve durability (see, e.g., U.S. Patent No. 6,451,396 to Zumbrum et al.). However, when gamma irradiation is used as a sterilization technique, such as in sterilizing disposable tubing for pump systems, the polymers degrade when exposed to gamma irradiation, shortening the pump's lifespan. Therefore, there is a continuing need for more durable pump tubing, especially when the tubing is sterilized by gamma irradiation (i.e., gamma sterilization). [Means for solving the problem]

[0005] SUMMARY OF THE DISCLOSURE The present disclosure generally relates to composite tubing for pumps comprising an elastomer reinforced with porous polyethylene.

[0006] According to a first embodiment ("Embodiment 1"), a composite tube includes a tube wall having at least one porous polyethylene layer, each of which is imbibed with at least one elastomer, thereby forming a composite layer having a modulus of elasticity less than 40 MPa and a first melting peak temperature less than 135°C.

[0007] Embodiment 2 is the composite tube of embodiment 1, wherein the composite tube has an average pump life of greater than 80 hours.

[0008] Embodiment 3 is the composite tube according to embodiment 1 or 2, wherein the tube wall has a volume fraction of 1% to 20%.

[0009] Embodiment 4 is the composite tube according to embodiment 3, wherein the composite layer has an elastic modulus of about 1 MPa to about 40 MPa.

[0010] Embodiment 5 is the composite tube according to embodiment 4, wherein the composite layer has an elastic modulus of about 1 MPa to about 24 MPa.

[0011] A sixth embodiment is the composite tube of the fifth embodiment, wherein the composite layer has an elastic modulus of about 1 MPa to about 13 MPa.

[0012] Embodiment 7 is the composite tube according to embodiment 6, wherein the composite layer has an elastic modulus of about 1 MPa to about 7 MPa.

[0013] Embodiment 8 is the composite tube according to any one of embodiments 1 to 7, wherein the porous polyethylene is expanded polyethylene (ePe).

[0014] Embodiment 9 is the composite tube according to any one of Embodiments 1 to 8, wherein the porous polyethylene is expanded ultra-high molecular weight polyethylene.

[0015] Embodiment 10 is the composite tube according to any one of embodiments 1 to 9, wherein the elastomer is selected from silicone, diene rubber, butyl rubber, fluoroelastomer, perfluoroelastomer, perfluoropolyether elastomer, or thermoplastic elastomer including styrene, polyether, polyester, or polyurethane block copolymer, or a combination thereof.

[0016] Embodiment 11 is the composite tube of any of embodiments 1-10, wherein the at least one elastomer is at least partially imbibed through the thickness of the porous polyethylene layer.

[0017] Embodiment 12 is the composite tube according to any one of embodiments 1 to 11, wherein the composite tube has been sterilized by gamma rays, steam, autoclave, EtO, X-rays, electron beam, dry heat, or cleaned in place (CIP).

[0018] Embodiment 13 is the composite tube according to any one of embodiments 1 to 12, wherein the tube is a tubing material for a peristaltic pump.

[0019] According to another embodiment ("Embodiment 14"), a peristaltic pump tubing includes a tube wall having at least one porous polymer layer, each of the porous polymer layers imbibed with at least one elastomer, thereby forming a composite layer having an elastic modulus of less than 40 MPa, and the peristaltic pump tubing has an average pump life of 300 hours to 5000 hours.

[0020] Embodiment 15 is the pump tubing of embodiment 14, wherein the composite layer has a first melting peak temperature of less than 135°C.

[0021] Embodiment 16 is the pump tubing of embodiment 14 or 15, wherein the tube wall has a volume fraction of 1% to 13%.

[0022] Embodiment 17 is the pump tubing according to embodiment 16, wherein the composite layer has an elastic modulus of about 1 MPa to about 40 MPa.

[0023] Embodiment 18 is the pump tubing according to embodiment 17, wherein the composite layer has an elastic modulus of about 1 MPa to about 24 MPa.

[0024] Embodiment 19 is the pump tubing of embodiment 18, wherein the composite layer has an elastic modulus of about 1 MPa to about 13 MPa.

[0025] Embodiment 20 is the pump tubing of embodiment 19, wherein the composite layer has an elastic modulus of about 1 MPa to about 7 MPa.

[0026] Embodiment 21 is a pump tubing material according to any one of embodiments 14 to 20, wherein the peristaltic pump tubing material has been sterilized by gamma rays, steam, autoclave, EtO, X-rays, electron beam, dry heat, or cleaned in place (CIP).

[0027] Embodiment 22 is the pump tubing of any of embodiments 14-21, wherein the at least one elastomer is at least partially imbibed through the thickness of the porous polyethylene layer.

[0028] Embodiment 23 is a pump tubing material according to any one of embodiments 14 to 22, wherein the elastomer is selected from silicone, diene rubber, butyl rubber, fluoroelastomer, perfluoroelastomer, perfluoropolyether elastomer, or thermoplastic elastomer including styrene, polyether, polyester, or polyurethane block copolymer, or a combination thereof.

[0029] Embodiment 24 is the pump tubing of embodiment 14, wherein the at least one porous polymer layer is selected from porous polyethylene, polypropylene, poly(ether ketone) (PEEK), and copolymers of ethylene and at least one comonomer.

[0030] Embodiment 25 is the pump tubing of any one of Embodiments 14 to 24, wherein the at least one porous polymer layer comprises at least one of expanded polyethylene and ultra-high molecular weight polyethylene.

[0031] In yet another embodiment ("Embodiment 26"), a composite tube includes a tube wall having at least one polyethylene layer, each of which is coated with at least one elastomer to form a composite layer having a modulus of elasticity less than 40 MPa and a first melting peak temperature less than 135°C.

[0032] Embodiment 27 is the composite tube of embodiment 26, wherein the composite tube has an average pump life of greater than 80 hours.

[0033] Embodiment 28 is the composite tube of embodiment 26 or 27, wherein the tube wall has a volume fraction of 1% to 20%.

[0034] Embodiment 29 is the composite tube of embodiment 28, wherein the composite layer has a modulus of elasticity of about 1 MPa to about 40 MPa.

[0035] Embodiment 30 is the composite tube of embodiment 29, wherein the composite layer has a modulus of elasticity of about 1 MPa to about 24 MPa.

[0036] Embodiment 31 is the composite tube of embodiment 30, wherein the composite layer has a modulus of elasticity of about 1 MPa to about 13 MPa.

[0037] Embodiment 32 is the composite tube of embodiment 31, wherein the composite layer has a modulus of elasticity of about 1 MPa to about 7 MPa.

[0038] Embodiment 33 is the composite tube of any one of embodiments 26 to 32, wherein the elastomer is selected from silicone, diene rubber, butyl rubber, fluoroelastomer, perfluoroelastomer, perfluoropolyether elastomer, or thermoplastic elastomer including styrene, polyether, polyester, or polyurethane block copolymer, or a combination thereof.

[0039] Embodiment 34 is the composite tube according to any one of embodiments 26 to 33, wherein the polyethylene layer comprises oriented polyethylene.

[0040] Embodiment 35 is the composite tube according to any one of embodiments 26 to 34, wherein the polyethylene layer comprises oriented ultra-high molecular weight polyethylene.

[0041] Embodiment 36 is the composite tube of any of embodiments 26-35, wherein the at least one elastomer forms a coating on the at least one polyethylene layer.

[0042] Embodiment 37 is the composite tube according to any one of embodiments 26 to 36, wherein the composite tube has been sterilized by gamma rays, steam, autoclave, EtO, X-rays, electron beam, dry heat, or cleaned in place (CIP).

[0043] Embodiment 38 is the composite tube according to any one of embodiments 26 to 37, wherein the tube is a tubing material for a peristaltic pump.

[0044] In another embodiment ("Embodiment 39"), the peristaltic pump tubing comprises gamma-sterilized polymer tubing having an average pump life of 300 to 5000 hours.

[0045] In another embodiment ("Embodiment 40"), the pump has a sterilized, non-fluoropolymer tubing having an average pump life of 300 to 5000 hours.

[0046] The above-described embodiments are merely examples and should not be construed as limiting or narrowing the scope of the inventive concepts provided by the present disclosure. While multiple embodiments are disclosed, still other embodiments will become apparent to those skilled in the art from the following detailed description. Accordingly, the drawings and detailed description are to be regarded as illustrative in nature and not restrictive. [Brief explanation of the drawings]

[0047] The accompanying drawings are included to provide a further understanding of the disclosure, are incorporated into and constitute a part of this specification, illustrate embodiments, and together with the description, serve to explain the principles of the disclosure.

[0048] [Figure 1] FIG. 1 illustrates a peristaltic pump with pump tubing according to one embodiment.

[0049] [Figure 2] 1 is a cross-sectional view of pump tubing according to one embodiment.

[0050] [Figure 3] FIG. 1 shows a differential scanning calorimetry (DSC) curve of a composite tube having a silicone elastomer reinforced with UHMWPE, according to one embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0051] Definitions and Terminology The present disclosure is not intended to be construed in a limiting sense, for example, the terms used in this application should be interpreted broadly in light of the meaning that one of ordinary skill in the art would assign to such terms.

[0052] As used herein, the term "membrane" refers to a polymer in the form of a substantially two-dimensional sheet, in which both the length and width are much greater than the thickness, e.g., both the length and width are at least 100 times the thickness. In some embodiments, the membrane is a microporous membrane, e.g., one having a structure that allows water vapor to pass through the thickness of the membrane, but does not allow liquid water to permeate from one side of the membrane to the other.

[0053] The term "film" refers to a membrane whose pores are at least partially filled with polymer such that gas or liquid flow does not occur through the open channels in the membrane.

[0054] As used herein, the term "porous" means that the porosity of the membrane or layer is sufficient to allow penetration of the elastomer.

[0055] As used herein, the term "on" is intended to indicate that an element is directly on top of another element, or that an element is indirectly on top of another element through an intervening element.

[0056] As used herein, the singular forms "a," "an," and "the" include plural references unless the context clearly dictates otherwise.

[0057] As used herein, the term "pump life" is intended to refer to the length of time that a tube can withstand use in a peristaltic pump before failure.

[0058] As used herein, the term "number of turns" is intended to refer to the number of layers of polymer (eg, oriented polyethylene) within the tube wall.

[0059] As used herein, the term "volume fraction" is intended to refer to the ratio of polymer (e.g., expanded polyethylene) to elastomer (e.g., silicone) within a given tubing construction, expressed as a percentage (%) of the total volume.

[0060] As used herein, the term "gamma irradiation" is intended to refer to a sterilization technique in which the tube is exposed to gamma radiation, which can be measured in kilograys (kGy).

[0061] The terms "ultra-high molecular weight polyethylene" and "(UHMWPE)" are used interchangeably and, as used herein, are intended to refer to a homopolymer of ethylene or a copolymer of ethylene and at least one comonomer (e.g., an alpha-olefin or cyclic olefin having 3 to 20 carbon atoms). The comonomer may be present in the UHMWPE copolymer in an amount of from about 0.001 mol% to about 10 mol%. The UHMWPE polymer has a weight average molecular weight (Mw) of from about 500,000 g / mol to about 10,000,000 g / mol.

[0062] As used herein, the term "differential scanning calorimetry (DSC) curve" is intended to refer to a schematic curve showing the amount of energy (y) required to maintain each temperature (x) as a temperature range is scanned.

[0063] As used herein, the term "first melting peak temperature" is intended to refer to the peak temperature at the largest melting endotherm as defined by the area under the endotherm in a DSC curve.

[0064] The terms "about" and "approximately" may be understood to mean the stated value plus or minus 10%. Description of Various Embodiments

[0065] Those skilled in the art will readily appreciate that the various aspects of the present disclosure may be implemented by any number of methods and apparatuses configured to perform the intended functions. It should also be noted that the accompanying drawings referred to herein are not necessarily drawn to scale and may be exaggerated to illustrate various aspects of the present disclosure, and in that respect the drawings should not be construed as limiting.

[0066] 1 is a perspective view of a peristaltic pump 100 having a porous polyethylene reinforced elastomer, the porous polyethylene reinforced elastomer being used in a pump tubing according to an embodiment of the present invention;

[0067] 2 is a cross-sectional view of a composite tube 200 according to one embodiment. The composite tube 200 can be pump tubing used in a peristaltic pump (e.g., the peristaltic pump shown in FIG. 1). In some examples, the composite tube 200 can be used in a pinch valve. In some examples, the composite tube 200 can have a cross-sectional shape that is a concentric circle, as shown in FIG. 2, for example. In some examples, the composite tube 200 can have a helical cross-section.

[0068] In one embodiment, as shown in FIG. 2, a composite tube 200 includes a tube wall (w) having at least one porous polyethylene layer 204. Each porous polyethylene layer 204 may be imbibed with at least one elastomer 206, thereby forming a composite layer 208 having a modulus of elasticity less than about 40 MPa and a first melting peak temperature less than about 135°C. For example, the composite tube 200 shown in FIG. 2 has a tube wall (w) including five composite layers 208. In some examples, the composite layer 208 may have a first melting peak temperature greater than about 127°C and less than about 145°C. A second melting temperature higher than the first melting peak temperature may be observed in oriented films (e.g., films that are stretched or oriented in one direction). The second melting temperature (e.g., associated with a second endotherm) may be between about 145°C and about 155°C.

[0069] The composite layer 208 can be manufactured by any one of a variety of methods, including gravure coating to impregnate a porous polyethylene layer with an elastomer, as discussed and shown, for example, in U.S. Patent No. 6,451,396 to Zumbrum et al. Optionally, the impregnated polyethylene layer (i.e., composite layer 208) can be conveyed to another roller for applying a topcoat of liquid elastomer. The amount of liquid elastomer impregnated into the polyethylene layer can be varied to produce a composite with a desired elastomer content. The coated structure is then wound in an uncured state around a cylindrical mandrel and either wound to a desired wall thickness or passed through a convection oven to cure the liquid elastomer to form a polyethylene-reinforced elastomer membrane. The elastomer-impregnated polyethylene in an uncured state can be heated on a mandrel to form a tubular article, such as pump tubing (e.g., pump tubing 102 shown in FIG. 1). In some instances, the coated film can be wound onto a mandrel and sliced ​​into tapes of desired widths, which can then be wound onto a mandrel using filament winding techniques to create three-dimensional objects of irregular shapes and infinite length.

[0070] In some embodiments, the composite tube 200 can have a volume fraction, expressed as a percentage (%) of the total volume of polymer to elastomer within a given tubing construction, of about 1% to about 20%. In some examples, the composite tube 200 can have a volume fraction of about 2% to about 18%, or about 3% to about 15%, or about 4% to about 14%, or about 4% to about 13%. In one embodiment, the composite tube 200 can have a volume fraction of about 7% to about 13%. In yet another embodiment, the composite tube 200 can have a volume fraction of about 4% to about 7%.

[0071] In some examples, the modulus value of composite layer 208 correlates with the volume fraction of the UHMWPE-based reinforcing film. In some embodiments, the modulus of composite layer 208 may range from about 1 MPa to about 40 MPa, from about 1 MPa to about 35 MPa, from about 1 MPa to about 30 MPa, from about 1 MPa to about 25 MPa, from about 1 MPa to about 20 MPa, from about 1 MPa to about 15 MPa, from about 1 MPa to about 10 MPa, or from about 1 MPa to about 5 MPa. In some embodiments, the modulus of composite layer 208 may range from about 1 MPa to about 7 MPa, or from about 1 MPa to about 13 MPa, or from about 1 MPa to about 24 MPa. Using the Voight two-phase composite model, the change in modulus of composite layer 208 as a function of the volume fraction of the reinforcing film can be estimated. Table 1 shows the upper and lower bounds of the modulus estimated using the Voight composite model for various volume fraction ranges of tubing with an inner diameter of about 6.4 mm and a tube wall thickness of 2.4 mm. The Voight two-phase composite model is as follows: c ) and the elastomer volume fraction (V e ) and the volume fraction of the reinforcing layer (V f ), and the elastic modulus of the elastomer (E e ) and the elastic modulus of the reinforcing layer (E f ) shows a correlation with: E c =E f V f +E e V e . [Table 1]

[0072] In some examples, the porous polyethylene of layer 204 can be expanded polyethylene (ePe). In some embodiments, the porous polyethylene can be expanded ultra-high molecular weight polyethylene (eUHMWPE). eUHMWPE polymer can have a first melting peak temperature greater than about 127°C and less than about 145°C. A second melting temperature higher than the first melting peak temperature can be observed in oriented films. For eUHMWPE, the second melting temperature (e.g., associated with the second endotherm) is between about 145°C and about 155°C.

[0073] In some examples, the polyethylene (hereinafter "polyethylene") forming polyethylene layer 204 can include a filler such as fumed silica, colloidal silica, carbon black, or a combination thereof. In some examples, the polyethylene can be plasma treated. In some examples, the polyethylene can optionally include a silane coupling agent. Polyethylene layer 204 can have a density of about 0.05 g / cc to about 0.8 g / cc. In some embodiments, layer 204 can have a density of about 0.1 g / cc to about 0.7 g / cc, about 0.2 g / cc to about 0.6 g / cc, about 0.3 g / cc to about 0.5 g / cc, or about 0.3 g / cc to about 0.4 g / cc.

[0074] In some embodiments, the composite tube 200 can have a wall thickness (i.e., the thickness of the tube wall (w)) of about 0.5 mm to about 10 mm. In some embodiments, the composite tube 200 can have a wall thickness of about 0.9 mm to about 9.2 mm, about 1 mm to about 8 mm, about 1.1 mm to about 7 mm, about 1.2 mm to about 6 mm, about 1.3 mm to about 5.5 mm, or about 1.4 mm to about 5 mm. In one embodiment, the composite tube 200 can have a wall thickness of about 1.5 mm to about 4.9 mm. Each composite layer can have a thickness of about 0.3 mm to about 10 mm. The ratio of the wall thickness to the inner diameter of the composite tube can be less than about 2 mm, less than about 1.9 mm, less than about 1.8 mm, less than about 1.7 mm, or less than about 1.6 mm. The number of turns of layer 204 in composite tube 200 can be from about 1 to about 200, or from about 1 to about 190, or from about 1 to about 185, or from about 1 to about 180, or from about 1 to about 175. In some embodiments, the number of turns of layer 204 in composite tube 200 can be from about 1 to about 170.

[0075] The composite tube 200 can include a reinforcing film, including, but not limited to, nonwovens, extruded films, cast films, stretched films, and phase inversion films. If the reinforcing film does not have adequate porosity as manufactured, such porosity can be imparted by mechanical methods. Polymers suitable for use as reinforcing films include, but are not limited to, polyethylene, polypropylene, polyether ketone (PEEK), and copolymers of ethylene and at least one comonomer. Suitable comonomers that can be used include, but are not limited to, alpha-olefins or cyclic olefins having 3 to 20 carbon atoms.

[0076] In some examples, the composite tube 200 has an average pump life of about 80 hours to about 5000 hours. In some examples, the composite tube 200 has an average pump life of about 88 hours to about 5000 hours. In some embodiments, the composite tube 200 has an average pump life of about 200 hours to about 4000 hours. In some embodiments, the composite tube 200 has an average pump life of about 250 hours to about 3000 hours. In some embodiments, the composite tube 200 has an average pump life of about 300 hours to about 3000 hours. In some embodiments, the composite tube 200 has an average pump life of about 100 hours to about 350 hours when exposed to about 50 kGy of gamma radiation. In some embodiments, the composite tube 200 has an average pump life of about 100 hours to about 320 hours when exposed to about 50 kGy of gamma radiation. In some examples, the gamma radiation may be greater than 50 kGy. In some embodiments, composite tube 200 is capable of exposure to about 20 kGy to about 60 kGy, or about 20 kGy to about 50 kGy, or about 20 kGy to about 40 kGy of gamma radiation. In some embodiments, composite tube 200 is capable of exposure to about 20 kGy to about 30 kGy of gamma radiation. In some examples, composite tube 200 is capable of multiple exposures to gamma radiation.

[0077] In some examples, the at least one elastomer 206 is at least partially imbibed through the thickness of the porous polyethylene layer 204, such that the at least one elastomer 206 forms a coating on the at least one polyethylene layer 204. In some embodiments, for example, the at least one elastomer 206 can be imbibed into the polyethylene layer 204 from about 1% to about 100%. In some embodiments, the at least one elastomer 206 can be imbibed into the polyethylene layer 204 from about 5% to 100% or less, from about 10% to 100% or less, from about 15% to 100% or less, or from about 20% to 100% or less.

[0078] The elastomer 206 can be selected from, but is not limited to, thermoset and thermoplastic elastomers. The elastomer 206 can be solvated or processed into tubing as is. Thermoset elastomers include diene-based rubbers, such as natural rubber, styrene-butadiene rubber (SBR), isoprene rubber (IR), butadiene rubber (BR), chloroprene rubber (CR), acrylonitrile-butadiene rubber (NBR), butyl rubber (isobutylene / isoprene rubber (IIR)), ethylene / propylene rubber (EPM), ethylene / propylene / diene rubber (EPDM), urethane resins, silicone rubber, fluoroelastomers (FKM), perfluorofluoroelastomers (FFKM), fluorosilicone rubber, and perfluoroether elastomers. Thermoplastic elastomers (TPEs) can include styrene, polyether, polyester, and polyurethane block copolymers.

[0079] Elastomer 206 can include a silicone (e.g., methylsilicone, phenylsilicone, fluorosilicone, etc.). In some examples, elastomer 206 can include an organosilicone. In some examples, elastomer 206 can include a methylsilicone, a phenylsilicone, a fluorosilicone, or a combination thereof. In some examples, elastomer 206 can include a fluoroelastomer, a perfluoroelastomer, a perfluoropolyether elastomer, or a thermoplastic elastomer including a styrene, polyether, polyester, polyurethane block copolymer, or a combination thereof.

[0080] In some examples, composite tube 200 is sterilizable. For example, composite tube 200 is sterilizable by gamma (γ) radiation, steam, steam in place (SIP), clean in place (CIP), autoclave, electron beam, x-ray, dry heat, and ethylene oxide (EtO). In one embodiment, composite tube 200 is sterilizable by gamma (γ) radiation.

[0081] In some embodiments, peristaltic pump tubing includes at least one porous polymer layer, each of which is imbibed with at least one elastomer, thereby forming a composite layer having a modulus of elasticity of less than 40 MPa. In some examples, the gamma-sterilized polymer tubing has an average pump life of about 24 hours to about 1950 hours, about 25 hours to about 1900 hours, about 26 hours to about 1850 hours, about 27 hours to about 1830 hours, about 28 hours to about 1810 hours, or about 29 hours to about 1800 hours. In some examples, the gamma-sterilized polymer tubing has an average pump life of about 30 hours to about 1780 hours.

[0082] In some embodiments, the composite tube includes a tube wall having at least one polyethylene layer, each polyethylene layer coated with at least one elastomer, thereby forming a composite layer having a modulus of less than about 11 MPa and a first melting peak temperature of less than 135°C. In some examples, the composite layer can have a first melting peak temperature greater than about 127°C and less than about 145°C. A second, higher temperature endotherm can be observed in the oriented film. The second endotherm is between about 145°C and about 155°C. In some examples, the composite tube has an average pump life of greater than about 190 hours. In some examples, the at least one elastomer forms a coating on the at least one polyethylene layer.

[0083] In some embodiments, the peristaltic pump tubing comprises gamma-sterilized polymer tubing, which has an average pump life of about 80 hours to about 5,000 hours, or about 83 hours to about 4,500 hours, or about 85 hours to about 4,000 hours, or about 88 hours to about 3,500 hours. In some embodiments, the gamma-sterilized polymer tubing can have an average pump life of about 90 hours to about 5,000 hours, or about 100 hours to about 4,800 hours, or about 110 hours to about 4,600 hours, or about 120 hours to about 4,400 hours, or about 130 hours to about 4,200 hours, or about 140 hours to about 4,100 hours, or about 150 hours to about 4,000 hours. In some embodiments, the gamma-sterilized polymer tubing can have an average pump life of about 300 hours to about 3,000 hours.

[0084] In some embodiments, sterilized non-fluoropolymer tubing can have an average pump life of 80 hours to 5000 hours, or about 83 hours to about 4500 hours, or about 85 hours to about 4000 hours, or about 88 hours to about 3500 hours. In some embodiments, sterilizable non-fluoropolymer tubing can have an average pump life of about 90 hours to about 5000 hours, or about 100 hours to about 4800 hours, or about 110 hours to about 4600 hours, or about 120 hours to about 4400 hours, or about 130 hours to about 4200 hours, or about 140 hours to about 4100 hours, or about 150 hours to about 4000 hours. In some embodiments, sterilizable non-fluoropolymer tubing can have an average pump life of about 300 hours to about 3000 hours.

[0085] Figure 3 is a schematic differential scanning calorimetry (DSC) curve 300 of an ultra-high molecular weight polyethylene tube, according to one embodiment. The UHMWPE polymer has a first melting peak temperature (e.g., corresponding to the first endotherm) that is greater than about 127°C and less than about 145°C. In some embodiments, for example, as shown in Figure 3, the UHMWPE polymer can have a first melting peak temperature of 131°C at first peak 302. In some embodiments, a second melting temperature (e.g., corresponding to the second endotherm) is shown in second peak 304 of Figure 3 and is between about 145°C and about 155°C. Test Method Pump Life

[0086] Sample tubing was cut to lengths between 152 mm and 356 mm using a standard tubing cutter. The tubing was fitted with a single, highly polished, quick-clamp sanitary tubing fitting (appropriately sized depending on the desired tubing being tested), which was secured to one end of the tubing with a single shaft collar. The shaft collar was then tightened finger-tight using an Allen wrench. The tubing was then placed into a Masterflex 07551-20 pump drive equipped with a Masterflex 77200-52 pump head. The pump tubing was centered in the pump head. The end of the tubing, fitted with a quick-clamp connection, was positioned with the shaft collar toward the outlet of the setup. For counterclockwise rotation, the shaft collar was positioned on the right side of the pump head before fully closing it. For clockwise rotation, the shaft collar was positioned on the left side of the pump head before fully closing it. The pump drive was then set to the following settings: continuous flow, 1700 RPM, tubing size ## (number set to the appropriate size depending on the desired tubing being tested).

[0087] A fluid reservoir (Nalgene model 2015-2000) was filled with deionized water to a volume of over 1800 mL. The cap (Nalgene model 2135-5302) was replaced on the reservoir. One of the tubes extending from the fluid reservoir cap was connected to the end of the sample tubing without the quick clamp connection using a reducer bender / splitter.

[0088] The end of the sample tubing with the quick-clamp connection was connected to the flow path using a quick-clamp tubing connector. The flow path contained the following components, listed in order of their placement within the flow path: outlet tubing with a quick-clamp connector, a stainless steel check valve (McMaster-Carr Model 1874N13, commercially available from McMaster-Carr), a pressure sensor (GEMS SENSORS Model 2200BGG1002A3UA), a pressure regulator (Go regulator Model BP3-2A41I5I111), and a flow meter (IFM efector Model SM600) with a mounting adapter (IFM efector Model E40200), which was then reconnected to the fluid reservoir using a reducer / splicer. The pressure sensor was used to measure the pressure within the setup throughout the test period and collected by the WONDERWARE software (sampling rate: one measurement every 30 seconds). The flow rate in the setup was measured throughout the test using a flow meter and collected by the WONDERWARE software (the sampling rate was one measurement every 30 seconds). The pump drive was then turned on and the pressure in the system was set to 20 psi using the pressure knob.

[0089] A sample was deemed to have failed the test under two circumstances. The first was when the tubing was broken and a visible liquid water leak was observed flowing out of the pump head. The second was when the flow rate was attenuated during analysis of the flow rate data throughout the test. The flow rate data was analyzed by recording the initial flow rate value of the sample two minutes after the desired pressure was set in the system. This initial flow rate value was then compared to the average flow rate for the most recent 30 minutes of the test (e.g., at 1 hour and 3 minutes, the average flow rate value calculated by averaging all flow rate data collected from 33 minutes to 1 hour and 3 minutes was reported). If this average flow rate value fell below 75% of the initial flow rate value, the sample was deemed to have failed the test and the test was stopped. The cumulative time, in hours, from the start of the test to when the tubing broke or the flow rate attenuated by more than 25% occurred was reported. Differential scanning calorimetry (DSC) and first melting peak temperature

[0090] Differential scanning calorimetry data were collected using a Q2000 DSC (159 Lukens Drive, New Castle, Delaware, USA, 19720) with a TZero aluminum pan and lid. Scans were run from 25°C to 200°C at 10°C / min. A 2mm diameter biopsy punch was used to cut plugs from the sidewall of the tube. The plugs were then divided into pucks approximately 1mm thick x 2mm diameter. The primary melting peak temperature was taken as the peak of the melting endotherm centered below 145°C. Elastic modulus

[0091] The elastic modulus of a composite layer (e.g., composite layer 208 shown in Figure 2) was measured from a layer peeled from a tube. The composite layer was peeled from the tube by inserting blunt-tipped tweezers between the layers and initiating peel along the long axis of the tube. A sufficient length of peel was allowed to form a nearly single composite layer. Tensile specimens were cut from the peeled layer in the hoop direction (peel direction) using an ASTM D638V dogbone die. Tensile behavior was measured using an Instron® Model 5564 (Illinois Tool Works Inc., Norwood, Massachusetts) equipped with flat grips and a 100 N load cell. The grip distance was 25.4 mm, the gauge length was 7.62 mm, and the crosshead speed was 1.27 mm / s (16.6% / s). The elastic modulus was calculated from the initial linear portion of the engineering stress (load / area) / engineering strain (change in length / gauge length) curve. A minimum of two samples were tested and the reported modulus is the average of the individual values. Thickness measurement

[0092] The sample thickness of the peeled layer was measured using a Mitotoyo Absolute Digital Micrometer, Model ID-C112E (Mitutoyo America Corporation, Aurora, Illinois) with a 6.35 mm diameter flat probe. Three measurements were taken, and the average thickness was reported. volume fraction

[0093] The volume fraction of silicone was calculated by adding the thickness of the silicone in the impregnated layer (e.g., layer 208 shown in Figure 2) to the thickness of the silicone topcoat layer (i.e., the silicone that resides on top of the membrane but not within the membrane pores). The impregnated layer is a layer of ePe-containing material whose pores are filled with silicone. The silicone content of the impregnated layer was calculated by dividing the ratio of the expanded polyethylene density to the polyethylene density by the total thickness of the composite.

[0094] In some embodiments, the silicone topcoat may be approximately 0.056 mm thick with a density ratio of 0.16 g / cc / 0.94 g / cc of 0.17, which gives a silicone content of 0.02 mm in the impregnated layer, divided by the total thickness of 0.08 mm, for a volume % of 5.1. Example Example 1

[0095] Peristaltic pump tubing ("Sample I") (d = 6.4 mm, w = 2.4 mm) was prepared by first obtaining a UHMWPE film of the same composition as defined in U.S. Patent No. 10,577,468 to Sbriglia. The UHMWPE film was passed between a gravure roll and a silicone rubber roll, and then passed through two chrome rolls with a 3.5 mil gap between them containing liquid silicone, as described in U.S. Patent No. 6,451,396 to Zumbrum et al. The UHMWPE film was coated at a rate of 2 feet per minute and wound around a mandrel with an outer diameter of 6.4 mm (i.e., the inner diameter of the composite tube). A composite tube with a wall thickness of 2.4 mm was obtained.

[0096] The uncured composite tube was then placed in a press at 135°C for 12 minutes at 20 tons of pressure and removed from the mandrel. The pump tubing was post-baked at 110°C for 6 hours to achieve a final cure and remove all volatiles. Additional processing in the form of a heat treatment was then completed as described in U.S. Patent Application Publication No. 2021 / 0317276 by Bell et al. The pump tubing was then gamma sterilized at doses ranging from 29 kGY to 34 kGY. The volume fraction of the resulting tube was then determined to be 6%.

[0097] The composite elastomer tubing of Sample I was then tested according to the pump life test method described above. The composite elastomer tubing of Sample I failed at approximately 1781 hours (n=2, max=1942 hours). The modulus of elasticity for Sample I was determined to be 9.8 MPa. The peak melting temperature of Sample I was determined to be 132.7°C. The data are shown in Table 2. Example 2

[0098] Peristaltic pump tubing ("Sample II") (d = 6.4 mm, w = 2.4 mm) was prepared by first obtaining a UHMWPE film of the same composition as defined in U.S. Patent No. 10,577,468 to Sbriglia. The UHMWPE film was passed between a gravure roll and a silicone rubber roll, and then passed through two chrome rolls with a 3.5 mil gap between them containing liquid silicone, as described in U.S. Patent No. 6,451,396 to Zumbrum et al. The UHMWPE film was coated at a rate of 2 feet per minute and wound around a mandrel with an outer diameter of 6.4 mm (i.e., the inner diameter of the composite tubing). A wall thickness of 2.4 mm was obtained.

[0099] The uncured composite was then placed in a press at 135°C for 12 minutes at 20 tons of pressure and removed from the mandrel. The pump tubing was baked at 110°C for 6 hours to achieve a final cure and remove all volatiles. The pump tubing was then gamma sterilized at doses ranging from 29 kGY to 34 kGY. The volume fraction of the resulting tube was then determined to be 6%.

[0100] The composite elastomer tubing of Sample II was then tested according to the pump life test method described above. The composite elastomer tubing of Sample II failed in approximately 24 hours (n=2, max=26 hours). The modulus of elasticity for Sample II was determined to be 22.5 MPa. The peak melting temperature of Sample II was determined to be 138°C. The data are shown in Table 2. Example 3

[0101] Peristaltic pump tubing ("Sample III") (d = 6.4 mm, w = 2.4 mm) was prepared by first obtaining ePe membrane (3P07A membrane from WL Gore & Associates, Inc., Heerlen, The Netherlands). The ePe membrane was 0.016 mm thick and 914 mm wide and obtained as a continuous roll. The density of the ePe membrane was 0.16 g / cc. The ePe membrane was passed between a gravure roll and a silicone rubber roll, and then passed through two chrome rolls with a 3.5 mil gap containing liquid silicone between them, as described in U.S. Patent No. 6,451,396 to Zumbrum et al. The ePe membrane was coated at a rate of 1 foot per minute and wound around a mandrel with an outer diameter of 6.4 mm (i.e., the inner diameter of the composite tubing). A wall thickness of 2.4 mm was obtained.

[0102] The uncured composite on the mandrel was then placed in a press at 135°C for 12 minutes at 20 tons of pressure and then removed from the mandrel. The pump tubing was post-baked at 110°C for 6 hours to achieve a final cure and remove all volatiles. Additional processing in the form of a heat treatment was completed as described in U.S. Patent Application Publication No. 2021 / 0317276 by Bell et al. The pump tubing was then gamma sterilized at doses ranging from 45 kGY to 51 kGY. The volume fraction of the resulting tube was then determined to be 4%.

[0103] The composite elastomer tubing of Sample III was then tested according to the pump life test method described above. The composite elastomer tubing of Sample III failed at approximately 10 hours (n=2, max=10 hours). The modulus of elasticity for Sample III was determined to be 2.9 MPa. The peak melting temperature of Sample III was determined to be 131.8°C. The data are shown in Table 2. Example 4

[0104] Peristaltic pump tubing ("Sample IV") (d = 6.4 mm, w = 2.4 mm) was prepared by first obtaining ePe membrane (3P07A membrane from WL Gore & Associates, Inc., Heerlen, The Netherlands). The ePe membrane was 0.016 mm thick and 914 mm wide and obtained as a continuous roll. The density of the ePe membrane was 0.16 g / cc. The ePe membrane was passed between a gravure roll and a silicone rubber roll, and then passed through two chrome rolls with a 3.5 mil gap containing liquid silicone between them, as described in U.S. Patent No. 6,451,396 to Zumbrum et al. The ePe membrane was coated at a rate of 1 foot per minute and wound around a mandrel with an outer diameter of 6.4 mm (i.e., the inner diameter of the composite tube). A composite tube with a wall thickness of 2.4 mm was obtained.

[0105] The uncured composite was then placed in a press at 135°C for 12 minutes at 20 tons of pressure and then removed from the mandrel. The pump tubing was baked at 110°C for 6 hours to achieve a final cure and remove all volatiles. The pump tubing was then gamma sterilized at 45-51 kGY. The volume fraction of the resulting tube was then determined to be 4%.

[0106] The composite elastomer tubing of Sample IV was then tested according to the pump life test method described above. The composite elastomer tubing of Sample IV failed at approximately 32 hours (n=2, max=53 hours). The modulus of elasticity of Sample IV was determined to be 7.8 MPa. The peak melting temperature of Sample IV was determined to be 140.9°C. The data are shown in Table 2. Example 5

[0107] Peristaltic pump tubing ("Sample V") (d = 6.4 mm, w = 2.4 mm) was prepared by first obtaining ePe membrane (3P07A membrane from WL Gore & Associates, Inc., Heerlen, The Netherlands). The ePe membrane was 0.016 mm thick and 762 mm wide and obtained as a continuous roll. The density of the ePe membrane was 0.16 g / cc. The ePe membrane was passed between a gravure roll and a silicone rubber roll, and then passed through two chrome rolls with a 1 mil gap containing liquid silicone between them, as described in U.S. Patent No. 6,451,396 to Zumbrum et al. The ePe membrane was coated at a rate of 3 feet per minute and wound around a mandrel with an outer diameter of 6.4 mm (i.e., the inner diameter of the composite tube). A composite tube with a wall thickness of 2.4 mm was obtained.

[0108] The uncured composite was then placed in an oven at 135°C for 24 minutes and then removed from the mandrel. The pump tubing was baked at 110°C for 6 hours to achieve a final cure and remove all volatiles. Additional processing in the form of a heat treatment was performed as described in U.S. Patent Application Publication No. 2021 / 0317276 by Bell et al. The pump tubing was then gamma sterilized at doses ranging from 45 kGY to 51 kGY. The volume fraction of the resulting tube was then determined to be 11%.

[0109] The composite elastomer tubing of Sample V was then tested according to the pump life test method described above. The composite elastomer tubing of Sample V failed at approximately 474 hours (n=2, max=936 hours). The modulus of elasticity of Sample V was determined to be 13.3 MPa. The peak melting temperature of Sample V was determined to be 133.2°C. The data are shown in Table 2. [Table 2]

[0110] The invention of this application has been described above generally and with reference to specific embodiments. It will be apparent to those skilled in the art that various modifications and variations may be made in the embodiments without departing from the scope of the present disclosure. Accordingly, the embodiments are intended to cover the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents.

Claims

1. A composite tube, the composite tube comprising:

1. A composite tube comprising a tube wall having at least one porous polyethylene layer, each of said porous polyethylene layers imbibed with at least one elastomer, thereby forming a composite layer having a modulus of elasticity of less than 40 MPa and a first melting peak temperature of less than 135°C.

2. 10. The composite tube of claim 1, wherein the composite tube has an average pump life of greater than 80 hours.

3. 3. The composite tube of claim 1, wherein the tube wall has a volume fraction of 1% to 20%.

4. The composite tube of claim 3 , wherein the composite layer has a modulus of elasticity of about 1 MPa to about 40 MPa.

5. The composite tube of claim 4, wherein the composite layer has a modulus of elasticity of about 1 MPa to about 24 MPa.

6. The composite tube of claim 5, wherein the composite layer has a modulus of elasticity of about 1 MPa to about 13 MPa.

7. The composite tube of claim 6, wherein the composite layer has a modulus of elasticity of about 1 MPa to about 7 MPa.

8. The composite tube according to any one of claims 1 to 7, wherein the porous polyethylene is expanded polyethylene (ePe).

9. The composite tube according to any one of claims 1 to 8, wherein the porous polyethylene is an expanded ultra-high molecular weight polyethylene.

10. 10. The composite tube according to claim 1, wherein the elastomer is selected from silicone, diene-based rubber, butyl rubber, fluoroelastomer, perfluoroelastomer, perfluoropolyether elastomer, or thermoplastic elastomer including styrene, polyether, polyester, or polyurethane block copolymer, or a combination thereof.

11. A composite tube according to any one of claims 1 to 10, wherein the at least one elastomer is at least partially imbibed through the thickness of the porous polyethylene layer.

12. The composite tube according to any one of claims 1 to 11, wherein the composite tube has been sterilized by gamma radiation, steam sterilization, autoclave sterilization, EtO sterilization, X-ray sterilization, electron beam sterilization, dry heat sterilization, or cleaned in place (CIP).

13. The composite tube according to any one of claims 1 to 12, wherein the tube is a tubing material for a peristaltic pump.

14. A tubing material for a peristaltic pump, the tubing material for a peristaltic pump comprising: a tube wall having at least one porous polymer layer, each of said porous polymer layers imbibed with at least one elastomer, thereby forming a composite layer having an elastic modulus of less than 40 MPa; The tubing for a peristaltic pump has an average pump life of 300 to 5000 hours.

15. 15. The pump tubing of claim 14, wherein the composite layer has a first melting peak temperature of less than 135°C.

16. 16. Pump tubing according to claim 14 or 15, wherein the tube wall has a volume fraction of 1% to 13%.

17. The pump tubing of claim 16, wherein the composite layer has an elastic modulus of about 1 MPa to about 40 MPa.

18. 18. The pump tubing of claim 17, wherein the composite layer has a modulus of elasticity of about 1 MPa to about 24 MPa.

19. 19. The pump tubing of claim 18, wherein the composite layer has a modulus of elasticity of about 1 MPa to about 13 MPa.

20. 20. The pump tubing of claim 19, wherein the composite layer has a modulus of elasticity of about 1 MPa to about 7 MPa.

21. The pump tubing according to any one of claims 14 to 20, wherein the peristaltic pump tubing has been sterilized by gamma rays, steam, autoclave, EtO, X-rays, electron beam, dry heat, or cleaned in place (CIP).

22. Pump tubing according to any one of claims 14 to 21, wherein the at least one elastomer is at least partially imbibed through the thickness of the porous polyethylene layer.

23. 23. The pump tubing of any one of claims 14 to 22, wherein the elastomer is selected from silicone, diene-based rubber, butyl rubber, fluoroelastomer, perfluoroelastomer, perfluoropolyether elastomer, or thermoplastic elastomer including styrene, polyether, polyester, polyurethane block copolymer, or a combination thereof.

24. 15. The pump tubing of claim 14, wherein the at least one porous polymer layer is selected from porous polyethylene, polypropylene, poly(ether ketone), and copolymers of ethylene and at least one comonomer.

25. The pump tubing of any one of claims 14 to 24, wherein the at least one porous polymer layer comprises at least one of expanded polyethylene and ultra-high molecular weight polyethylene.

26. A composite tube, the composite tube comprising:

1. A composite tube comprising a tube wall having at least one polyethylene layer, each of said polyethylene layers being coated with at least one elastomer, thereby forming a composite layer having a modulus of elasticity of less than 40 MPa and a first melting peak temperature of less than 135°C.

27. 27. The composite tube of claim 26, wherein the composite tube has an average pump life of greater than 80 hours.

28. 28. A composite tube according to claim 26 or 27, wherein the tube wall has a volume fraction of 1% to 20%.

29. 30. The composite tube of claim 28, wherein the composite layer has a modulus of elasticity of about 1 MPa to about 40 MPa.

30. 30. The composite tube of claim 29, wherein the composite layer has a modulus of elasticity of about 1 MPa to about 24 MPa.

31. 31. The composite tube of claim 30, wherein the composite layer has a modulus of elasticity of about 1 MPa to about 13 MPa.

32. 32. The composite tube of claim 31, wherein the composite layer has a modulus of elasticity of about 1 MPa to about 7 MPa.

33. 33. The composite tube according to any one of claims 26 to 32, wherein the elastomer is selected from silicone, diene-based rubber, butyl rubber, fluoroelastomer, perfluoroelastomer, perfluoropolyether elastomer, or thermoplastic elastomer including styrene, polyether, polyester, polyurethane block copolymer, or a combination thereof.

34. The composite tube of any one of claims 26 to 33, wherein the polyethylene layer comprises oriented polyethylene.

35. The composite tube of any one of claims 26 to 34, wherein the polyethylene layer comprises oriented ultra-high molecular weight polyethylene.

36. A composite tube according to any one of claims 26 to 35, wherein the at least one elastomer forms a coating on the at least one polyethylene layer.

37. The composite tube according to any one of claims 26 to 36, wherein the composite tube has been sterilized by gamma radiation, steam sterilization, autoclave sterilization, EtO sterilization, X-ray sterilization, electron beam sterilization, dry heat sterilization, or cleaned in place (CIP).

38. The composite tube of any one of claims 26 to 37, wherein the tube is a tubing material for a peristaltic pump.

39. A tubing material for a peristaltic pump, the tubing material for a peristaltic pump comprising: Tubing for a peristaltic pump comprising a gamma sterilized polymeric tube having an average pump life of 300 to 5000 hours.

40. A tubing material for a peristaltic pump, the tubing material for a peristaltic pump comprising: Tubing for a peristaltic pump comprising a sterilized non-fluoropolymer tubing having an average pump life of 300 to 5000 hours.

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