Multiple steam-sterilizable, sealable layer film of non-pvc polymers

ES 2 296 784 T3

DESCRIPTION

Non-adherent, autoclavable, heat-sealable polymer blends for making monolayer and multilayer films.

Field and background of the invention

In general, the present invention relates to polymeric blends for making films, and more particularly to films that have little distortion and are non-stick when steam sterilized, heat sealable, and suitable for making flexible medical containers.

In the medical field, where beneficial agents are collected, processed and stored in containers, transported and finally distributed in tubes by infusion to patients to obtain their therapeutic effects, the materials used to make the containers have to have a unique combination of properties. For example, visual inspection of solutions for particulate contamination requires an optically clear container. The material that forms the wall has to be flexible enough to infuse a solution by folding the walls of the container without introducing air into the container. The material must maintain its flexibility and firmness within a wide range of temperatures. The material must maintain its flexibility and firmness at low temperatures, as some solutions, for example some premixed drug solutions, are stored and transported in containers at temperatures between -25 and -30 ° C to minimize deterioration of the drug. The material also has to be functional and resist deformation at high temperatures to withstand the heat of steam sterilization; a process that most medical fluid and nutritional product containers undergo prior to shipment. Often times, the sterilization process includes exposing the container to steam at typical temperatures of 121 ° C and at elevated pressures.

To facilitate the manufacture of useful articles, it is desirable that the material can be sealed by heat sealing techniques. Therefore, the material must maintain sufficient thermoplastic properties to melt when heated.

Another requirement is to minimize the environmental impact when the article made from the material is discarded after use. For those items that are disposed of in landfills, it is desirable to minimize or avoid the incorporation of low molecular weight leachable components into the construction of the item. Other benefits are achieved by employing a material that allows thermal retreatment of waste material produced during manufacture.

For those containers that are disposed of by incineration to reduce biological hazards, it is desirable to use a material that reduces or eliminates the formation of corrosive and environmentally unacceptable inorganic acids.

It is also desirable that the material does not have or has a low content of low molecular weight additives, such as plasticizers, stabilizers and equivalents, which could be released and introduced into drugs or biological fluids.

Due to its ability to meet a wide variety of functional requirements, flexible polyvinyl chloride (PVC) material has often been chosen for application in medical bags. PVC also offers the clear advantage of being one of the cheapest materials to build devices that meet the above requirements. However, PVC has several disadvantages on the market. These disadvantages include the incompatibility of PVC compounds with certain drugs, concerns regarding their chlorine content and their effects on the environment, and an increasingly negative commercial perception of PVC in general. Thus, many materials have been found to replace PVC. However, most of the alternative materials are too expensive to apply and do not meet all of the above requirements.

Polyolefins and polyolefin alloys have been developed that meet many of the requirements for medical tubes and containers without the disadvantages associated with PVC. Polyolefins are normally compatible with medical applications as they have a relatively low extractability to fluids. Most polyolefins are safe for the environment, as they do not generate harmful degradants when incinerated, and are suitable for thermoplastic recycling. Many polyolefins are cost effective materials and can provide an inexpensive alternative to PVC. However, there are many hurdles to overcome to replace all the favorable attributes of PVC with polyolefins.

For example, problems have been encountered in the use of some polyolefins to make medical tubes. Such tubes have been found to have insufficient surface characteristics, making them very sensitive to cuts, pits or scratches when fixing the tubes with slide clamps. Furthermore, some polyolefins with favorable modular attributes, such as ultra-low density polyethylenes, have melting points below those obtained during an autoclave process.

It is well known that crosslinking by chemical agents or by high energy ionizing radiation increases the heat resistance of the polymer matrix. Chemical crosslinking is based on the formation of covalent bonds between

ES 2 296 784 T3 separate polymer chains, which greatly retards deformation and flow capacity at high temperatures, even above the melting point of polymers. For example, US Patent 4,465,487 assigned to Terumo describes the manufacture of autoclavable medical containers by irradiating ethylene-vinyl acetate copolymers with high-energy electron beams (2 Me-v) at doses between 50 kGy and 100 kGy to obtain gel contents between 50% and 85%. The '487 patent describes that if the EVA side walls of the container are irradiated to obtain a gel content of about 50% or more, prior to sealing them together, they easily peel apart (col. 4, lines 20 to 30 ). Thus, the '487 patent describes irradiating the container sidewalls after sealing the bag-shaped container, leaving only an entry and exit area unsealed.

Similarly, US Patent 4,453,940 describes the manufacture of medical containers with EVA and other materials. The '940 patent also describes the phase of increasing the autoclaving strength of EVA by crosslinking the material with high energy electron beams. The '940 patent advises that if the crosslinking exceeds 50%, the use of heat sealing is impossible (col. 4, lines 27 to 35).

US Patent 4,401,536 describes the crosslinking of semi-rigid containers composed of blends of polypropylene and EVA or EEA. This patent does not describe the use of ethylene alpha olefins with polypropylene. It also describes that irradiation prior to formation results in articles with poor heat sealing ability (col. 4, lines 25-28).

US Patents 4,892,604 and 5,066,290, both assigned to the present assignee, describe a medical container with an outer layer of coextruded high-density polyethylene and an inner layer of a copolymer of ethylene vinyl acetate, containing vinyl acetate. of approximately 18%. After the container has been manufactured by conventional radio frequency heat sealing, the assembly is subjected to ionizing radiation of approximately 100 kGy with an electron beam accelerator of approximately 5 Me-v. The high-density polyethylene layer acts as a barrier to moisture and gas transmission in order to maintain the sterile fluid content at a relatively constant concentration, as required by the various world pharmacopoeias. However, in this material composition, several important deficiencies were revealed: 1) To make a container with this material composition, the container must be manufactured before the crosslinking process, as it is difficult, if not impossible, to seal the crosslinked EVA layer (this makes the manufacturing process very ineffective) and 2) The radiation dose required for sufficient crosslinking also releases considerable amounts of acetic acid, a by-product of radiation exposure. Because HDPE is a barrier to gas transmission, retained acetic acid can cause fluid contents to become very acidic, a highly inconvenient result.

US Patent 4,643,926, assigned to WR Grace, describes the manufacture of a container for medical solutions from a multilayer material in which, in some embodiments, the layer to be heat sealed consists of polypropylene as the main ingredient. Because it is well known that polypropylenes undergo chain cleavage when exposed to radiation, the heat sealable layer continues to be thermoplastic and can be heat sealed to similar surfaces. Therefore, the entire multilayer film can be heat sealed and withstands autoclaving. However, the complexity of the multilayer structure and the possible need to wash and incorporate acid scrubbing compounds into the film (see US Patent 5,445,893) to remove acidic by-products caused by EVA irradiation make the process become very complicated and that its costs are very high. Furthermore, because the film is made up of many very different materials, the process of recycling the edge trimmings and other debris from the film is very difficult and impractical without greatly reducing the optical and mechanical properties.

US Patent 5,055328 describes a differentially cross-linked multilayer film where the heat-sealed layer contains additional antioxidants to delay cross-linking and facilitate post-cross-linking in heat-sealing. Similarly, Canadian patent 1,125,229 describes another differentially cross-linked multilayer film where the outer layer contains a cross-linking enhancer. However, these structures are all multi-layered and do not address the issue of self-adhesion during autoclaving.

US Patent 4,724,176 to Sun discloses an oriented heat shrinkable multilayer container with an outer layer crosslinked by irradiation and, by controlling the irradiation process, an inner seal layer not crosslinked. The inner and outer layers can be made of EVA copolymers. This container is designed to contract when heat is applied to it and therefore would not be suitable as a container that has to maintain substantially its full volume after an autoclaving process.

EP-A-153,742 describes a multilayer film and a container formed from such film.

The main objective of the present invention is to provide polymeric materials which are generally better than those already known, which are currently known from the state of the art or which have already been commercialized. The properties of such materials include flexibility, optical clarity for visual inspection, and sufficient heat resistance to withstand a steam sterilization process at temperatures up to 212 ° C without experiencing significant distortion or self-adhesion. Materials should be unoriented and non-adherent, and capable of withstanding sealing by heat sealing techniques. The materials must also be substantially free of low molecular weight leachable additives and must be capable of being disposed of by incineration without generating a

ES 2 296 784 T3 significant amount of corrosive inorganic acids. Finally, the material should serve as a cost-effective alternative to various PVC formulas that are currently used for medical devices.

US Patent 5,879,768 describes a bag for containing flowable materials made of a material having a sealing layer of a polymeric composition comprising: (A) between 10 and 100 percent of a mixture of (1) between the 5 and 95% of at least one substantially linear and homogeneously branched ethylene / α-olefin interpolymer, and (2) between 5 and 95% of high pressure low density polyethylene with a density ranging from 0.916 and 0.930 g / cc; and (B) 0 to 90% of a polymer selected from the group consisting of ultra-low-density polyethylenes, linear low-density polyethylenes, high-pressure low-density polyethylenes, ethylene-vinyl acetate copolymers, and polymers of homogeneously branched linear ethylene. The '768 patent does not disclose exposing this mixture to irradiation or mixing the homogeneously branched substantially linear ethylene / olefin interpolymer with polypropylene.

When more than one polymer is mixed to form an alloy composition, it is difficult to achieve all of the above objectives at the same time. For example, many alloys produce significant light scattering; therefore, they do not achieve the objective of optical clarity. The intensity of the photodispersion (measured by optical haze) depends on the domain size of the components on a micrometer scale (μ) and on the proximity of the refractive indices of the components. As a general rule, the selection of components that can be processed successfully in very small domain sizes, and even with minimal misalignments in refractive indices, is a difficult goal. The present invention is provided to solve these and other problems.

Summary of the invention

According to the present invention, there is provided a film, a method and a container according to claims 1 to 33.

The present invention provides a polymer blend for making monolayer films or a layer within a multilayer film. The mixture has a first and a second component. The first component is selected from the group of (1) interpolymers of ethylene and α-olefin having a density lower than 0.915 g / cc and obtained by "single-site" catalysis (of a single active site), (2) ionic polymers, commonly referred to as ionomers. The second component is selected from one or more of the following: (1) polymers containing propylene, (2) polymers containing butene, (3) polymers containing polymethylpentene, (4) polymers containing cyclic olefins, and (5) polymers containing bridging polycyclic hydrocarbons. The first component is present in an amount ranging from 99% to 55% and the second component is present in an amount, relative to the weight of the mixture, ranging from 45% to 1%.

When the mixture is manufactured as a film, it has a modulus of elasticity, measured according to ASTM D882, less than 414 MPa (60,000 psi), an internal haze, measured according to ASTM D1003, less than 25%, a self-adhesion greater than about 2 (as defined below), slight or no adhesion to overbag materials, a sample creep at 120 ° C at 0.2 MPa (27 psi) load less than or equal to 150%, and the film can be heat sealed in a gasket container where the gaskets remain intact when the liquid filled container is autoclaved at 121 ° C for one hour.

The present invention also provides a non-oriented PVC-free monolayer film with sufficient resistance to thermal distortion to withstand steam sterilization conditions. The film is manufactured from a mixture of a first component and a second component. The first component is selected from the group of (1) interpolymers of ethylene and α-olefin with a density lower than approximately 0.915 g / cc and which are obtained by "single-site" catalysis (of a single active site) and ( 2) ionic polymers, usually called ionomers. The second component is selected from one or more of the following: (1) polymers containing propylene, (2) polymers containing butene, (3) polymers containing polymethylpentene, (4) polymers containing cyclic olefins, and (5) polymers containing bridged polycyclic hydrocarbons. The first component is present in an amount ranging from 99% to 55% and the second component is present in an amount, relative to the mixture, ranging from 45% to 1%.

The film has a modulus of elasticity, measured according to ASTM D882, less than 414 MPa (60,000 psi), an internal optical haze, measured according to ASTM D1003, less than 25%, a self-adhesion greater than 2 (measured as will be defined later), little or no adhesion to overbag materials, has a sample creep at 120 ° C at 0.2 MPa (27 psi) load less than or equal to 150%, and the film can be heat sealed in a container with watertight joints, where the seals remain intact when the container filled with liquid is autoclaved at 121 ° C for one hour.

The present invention also provides a method of making an unoriented, non-PVC film. The method includes the steps of: providing a first component and a second component, mixing the first component with the second to define a mixture, extruding the mixture into a film and exposing the film to electron beam irradiation. The first component is selected from the group of: (1) interpolymers of ethylene and α-olefin with a density lower than 0.915 g / cc and obtained by "single-site" catalysis (of a single active site) and (2) ionic polymers, commonly referred to as ionomers. The second component is selected from one or more of the following: (1) polymers containing propylene, (2) polymers containing butene, (3) polymers containing

ES 2 296 784 T3 contain polymethylpentene, (4) polymers containing cyclic olefins and (5) polymers containing bridged polycyclic hydrocarbons. The first component is present in an amount ranging from 99% to 55% and the second component is present in an amount, relative to the weight of the mixture, ranging from 45% to 1%.

The film has a modulus of elasticity, measured according to ASTM D882, less than 414 MPa (60,000 psi), a haze, internal measured according to ASTM D1003, less than 25%, a self-adhesion greater than 2 (measured as indicated later) , slight or no adhesion to overbag materials, a sample creep at 120 ° C at a 0.2 MPa (27 psi) load less than or equal to 150%, and the film can be heat sealed in a container with gaskets , where the seals remain intact when the container filled with liquid is autoclaved at 121 ° C for one hour.

Brief description of the drawings

Figure 1: sectional view of a monolayer film of the present invention.

Figure 2: sectional view of a multilayer film of the present invention.

Figure 3: container of a material made with a film of the present invention.

Figure 4: IV fluid administration set

Figure 5: set of peritoneal dialysis vessels and tubes, and

Figure 6: Double chamber bag with a peelable seal that separates the chambers.

Detailed description of the invention

The present invention admits of many different embodiments. The preferred embodiments of the invention are described with the idea that this publication is considered as an illustration of the principles of the invention and without intending to limit the general aspects thereof to the embodiments shown.

I. Blends of polymers and monolayer films thereof

Figure 1 shows a monolayer film 10 of the present invention. Monolayer film 10 is manufactured from a polymer blend having a first component and a second component. The first component is selected from the group of: (1) interpolymers of ethylene and α-olefin with a density lower than approximately 0.915 g / cc and which are obtained by "single-site" catalysis (of a single active site) and of (2) ionic polymers, usually referred to as ionomers. The first component is present in an amount ranging from about 99% to about 55% by weight of the mixture, preferably from about 60% to about 85%, and especially from about 65% to about 80%.

The second component is selected from the group consisting of: (1) polymers containing propylene, (2) polymers containing butene, (3) polymers containing polymethylpentene, (4) polymers containing cyclic olefins, and (5) polymers containing bridging polycyclic hydrocarbons. The second component is present in an amount, relative to the weight of the mixture, ranging from about 45% to about 1%, preferably from about 15% to about 40% and especially from about 20%. % and approximately 35%.

The film has a modulus of elasticity, measured according to ASTM D882, less than about 414 MPa (60,000 psi), an internal haze, measured according to ASTM D1003, less than 25%, a self-adhesion greater than about 2 (such as to be defined later), slight or no adhesion to overbag materials, a sample creep at 120 ° C at a load of approximately 0.2 MPa (27 psi) less than or equal to 150%, and the film can be heat sealed in a tight joint container, where the seals remain intact when the liquid filled container is autoclaved at 121 ° C for one hour.

As used herein, the term "interpolymer" includes copolymers, terpolymers, whether random or blocky.

Interpolymers of ethylene and α-olefin preferably have a density, measured according to ASTM D792, of less than about 0.915 g / cc and are commonly referred to as very low density polyethylenes (VLPDE), ultra low density ethylenes (ULDPE) and the like. The α-olefin must have between 3 and 17 carbons, preferably between 4 and 12 and especially between 4 and 8 carbons. In a preferred form of the invention, the ethylene-α-olefin copolymers are obtained by "single-site" catalysis (of a single active site). Suitable single-site catalysis systems, among others, are described in US Patents 5,783,638 and 5,272,236. Suitable copolymers of ethylene and α-olefin include those sold by Dow Chemical Company under the trademark AFFINITY, by Dupont-Dow under the trademark ENGAGE, and by Exxon under the trademarks EXACT and PLASTOMER.

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Suitable polymers containing propylene include those selected from the group consisting of polypropylene homopolymers, copolymers and terpolymers of propylene with one or more comonomers selected from the α-olefins of 2 to 17 carbons. Suitable polypropylene copolymers and terpolymers include random or block propylene and ethylene copolymers or random or block propylene / ethylene / butene terpolymers. Montell sells suitable propylene α-olefin copolymers under the trademarks PRO FAX, PRO FAX ULTRA, and CATALLOY.

The present invention also contemplates the use of polymer blends containing propylene as the second blending component. In a preferred form of the invention, the blends include at least a first propylene-containing polymer and a second propylene-containing polymer. The first propylene-containing polymer and the second propylene-containing polymer can be selected from propylene homopolymers, copolymers and terpolymers, as already explained. In a preferred form of the invention, the first propylene-containing polymer differs from the second propylene-containing polymer in at least two respects. The first difference is that the first propylene-containing polymer should preferably have a melt flow rate about 3 times greater, and preferably about 5 times greater, than the melt flow rate of the second propylene-containing polymer. The second difference is that the first propylene-containing polymer preferably has a melting point of at least about 5 ° C higher, and preferably at least about 10 ° C higher, than the second propylene-containing polymer. Melting point is measured according to ASTM D3417 (Enthalpies of fusion and Crystallization of Polymers by Differential Scanning Calorimetry). The first propylene-containing polymer can be distinguished from the second propylene-containing polymer by the first difference, the second, or both.

Suitable homopolymers and copolymers of cyclic olefins and bridged polycyclic hydrocarbons and their mixtures can be found in US Patents 5,218,049, 5,854,349, 5,863,986,5,795,945, 5,792,824; and in European patents EP 0 291208, EP 0 283164, EP 0 497567.

In a preferred form of the invention, suitable cyclic olefin monomers are monocyclic compounds having between 5 and about 10 ring carbons. Cyclic olefins can be selected from the group consisting of substituted or unsubstituted cyclopentene, cyclopentadiene, cyclohexene, cyclohexadiene, cycloheptene, cycloheptadiene, cyclooctene, and cyclooctadiene. Suitable substituents include lower alkyls, acrylate derivatives, and the like.

In a preferred form of the invention, the bridged polycyclic hydrocarbon monomers have two or more rings and preferably contain at least 7 carbons. The cycles may or may not be substituted. Suitable substituents include lower alkyl, aryl, aralkyl, vinyl, allyloxy, (meth) acryloxy, and the like. Polycyclic bridging hydrocarbons are selected from the group consisting of those described in the aforementioned patents and patent applications. Ticona sells polymers containing bridging polycyclic hydrocarbons under the TOPAS trademark, Nipón Zeon sells them under the XEONEX and ZEONOR trademarks, Daikyo Gomu Seiko sells them under the CZ resin trademark, and Mitsui Petrochemical Company sells them under the APEL trademark.

In a preferred form of the present invention, the film will have the following physical characteristics: (1) a modulus of elasticity, measured according to ASTM D882, less than about 414 MPa (60,000 psi), (2) an internal haze, measured according to ASTM D1003, less than about 25%, (3) a self-adhesion greater than about 2, as defined below, (4) no adhesion to overpouch materials, (5) a sample creep at 120 ° C at about a 0.2 MPa (27 psi) load less than or equal to 150%, and (6) the film can be heat sealed in a gasketed container, where the gaskets remain intact when the liquid filled container is autoclaved at 121 ° C for one hour.

The film is also flexible enough to build containers of flowable materials. The film has a modulus of elasticity less than about 414 MPa (60,000 psi), preferably less than about 276 MPa (40,000 psi), especially less than about 207 MPa (30,000 psi), and even more preferably less than about 138 MPa ( 20,000 psi), measured per ASTM D882. When the fluid container is an IV container, it is desirable for the container to contract or contract substantially on emptying, and therefore should have a modulus of elasticity less than about 276 MPa (40,000 psi), especially less than about 207 MPa (30,000 psi), and even preferably less than about 138 MPa (20,000 psi), when measured in accordance with ASTM D882.

For the purposes of this invention, "self-adhesion" is defined as the tendency of the film to adhere to itself during autoclaving. This property can be determined by the following test. 20.3 x 5.1 cm (8 "x 2") strips of film are cut, with the largest dimension in the machine direction. These strips are rolled into tubes 5.1 cm (2 ") long and approximately 1.3 cm (0.5") in diameter. The rolled film is held in place by compressing the film layers together at one end with a paper clip. The tubes are then placed in a steam autoclave at 121 ° C for 30 minutes. The samples are allowed to cool for at least one hour. The film is then unrolled. The resistance to unwinding and the corresponding damage of the film are classified as shown in Table 1 below:

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TABLE 1

Grade Observed Result

The film cannot be unrolled without destroying it.

The film is difficult to peel off and significant surface damage occurs.

There is some resistance to peel and minor surface damage.

Little peel strength is observed with little or no surface damage.

No resistance to peel or surface damage is observed.

Grades are determined in three or more units and are recorded on average.

Adhesion to overbag materials is determined by the following qualitative test. One inch wide strips of film are sealed in typical overbags (medium or high density polyethylene). The overbag is then placed in a laboratory autoclave at 486 ° C (252 ° F) and at a pressure of 0.51 MPa (24.5 psi) for one hour. After autoclaving, the bags are cut open and the strips removed. If the films separate from the overbag without leaving marks on the surface of the film, they are classified as non-adhesion (N). If the separation of the film causes visible damage, it is classified (Y), which indicates that there are remains in the overbag. A rating can also be given to indicate slight adhesion (S).

Creep properties were determined at 120 ° C by fixing film strips with a thickness of between approximately 0.13 mm (5 mils) and approximately 0.38 mm (15 mils) in a controlled temperature oven and loading them with weights to produce a pressure of approximately 0.2 MPa (27 psi). After loading for 40 minutes, the film strips were removed and dimension changes were recorded in a 2.54 cm (1 inch) pre-scored gap.

The film can be sealed using standard heat sealing techniques. A suitable heat seal is formed when a fluid container such as that shown in Figure 3 is made from the film, sealing the peripheral edges to define a centrally disposed fluid chamber. The container is filled with water and subjected to an autoclave sterilization process. Proper heat seals remain intact at the end of the autoclave cycle.

The films of the present invention have a haze of less than about 25% and preferably less than about 15%, as measured by ASTM D1003. For the purposes of this invention, internal haze is defined as the haze value measured when both surfaces of the film have been moistened with isopropyl alcohol.

II. Polymer and Film Processing

To produce the film of the present invention, raw materials are fed into an extrusion hopper at a desired mixing ratio by weight feeders. The materials are extruded through an extrusion die to produce a monolayer film. The film is irradiated with a suitable energy source and then sealed to form a fluid container. Exposing the mixture to radiation prior to extrusion is also contemplated. The raw materials can also be premixed prior to extrusion using a single screw, two screws, or other mixing methods known to those skilled in the art.

The preferred method of irradiating the film is to expose it to an electron beam with a beam energy between approximately 150 Ke-v and 10 Me-v, preferably between 200 and 300 Ke-v and at a dose of between approximately 20 kGys and approximately 200 kGys and especially between approximately 60 and 150 kGys. On the other hand, the film can be cross-linked using the methods known to those skilled in the art. Crosslinking methods used in industry include exposure to ionizing radiation (gamma, beta, ultraviolet, etc.).

To reduce or minimize oxidative degradation of the film during and after exposure to the electron beam, it is desirable to reduce the partial pressure of oxygen in the area surrounding the radiation-exposed film. The partial pressure of oxygen can be reduced by applying a vacuum or another gas, such as nitrogen under pressure, or by other known techniques to achieve this goal. In a preferred form of the invention, the oxygen concentration during a nitrogen flush is less than about 100 ppm and preferably less than about 40 ppm.

III. Multilayer films

Figure 2 shows an example of a multilayer film 20 that includes a layer 12 of the monolayer described. In a preferred form of the invention, the monolayer will be the sealing layer. The multilayer film 20 may include

ES 2 296 784 T3 any additional layer 14 or a combination of other layers selected from those such as outer layers, RF sensitive layers and inner layers, to name a few.

An outer layer can be added to increase the scuff resistance of the film. The outer layer can be an olefinic material, such as propylene and ethylene homopolymers and copolymers. The outer layer can also be a polyester, a copolyester, a polyamide or a copolyamide. The term "copolyester" and equivalents apply to polyesters synthesized from more than one diol and one dibasic acid. Copolyesters as used herein can also be qualified as copolymers of polyether and polyethylene terephthalate. Preferably, the copolyesters as used herein may be qualified as polymeric materials derived from 1,4-cyclohexanedimethanol, 1,4-cyclohexanedioic acid, and polytetramethylene glycol ether, or equivalents of any of the foregoing, as reagents.

Suitable water vapor barriers include, but are not limited to, HDPE, MDPE, and polyesters (PET, PBT, PEN, etc.).

Appropriate gas barriers are those that prevent the passage of oxygen, carbon dioxide, or other gases. Suitable gas barriers include, but are not limited to, polyesters and polyamides.

The residual material that is generated before irradiation can be incorporated in one or more layers.

IV. Containers for flowable materials

Figure 3 shows a container for fluid material and specifically an IV container 30. Figure 4 shows an IV administration set 40 and Figure 5 shows a peritoneal dialysis equipment 50. The present invention further contemplates the manufacture of medical tubes to starting from the mixtures of the present invention. It is contemplated that the irradiation treatment of the tubes differs from that of the films due to the greater thickness and round shape of the tubes, although the tubes can be effectively treated within the radiation ranges discussed above for the film. What is meant by "fluid material" is a material that flows thanks to the force of gravity. Thus, flowable materials include both liquid components and powdered or granular components and the like. Container 30 has side walls 32 that match and are sealed at peripheral edges to define a chamber 34 that contains fluid materials, such as liquids or granular materials. For containers made solely by blow molding or by blow extrusion, the longitudinal edges are sealed. An inlet and outlet tube 36 or several inlet and outlet tubes are provided to fill and empty the contents of the container 30. The side walls and the inlet and outlet tube can be fabricated from one of the above monolayer and multilayer films. exposed. Surprisingly, medical components made from the disclosed films and blends can be heat sealed even though the film has been irradiated with electron beam radiation.

Thermal seals can be obtained by applying standard heat sealing techniques known to those skilled in the art.

V. Containers with Peelable Seals and Double Chamber

Figure 6 shows a double chamber container 70 with a first chamber 72 and a second chamber 74 separated by a peelable seal 76. The container side walls 75 are manufactured from one of the polymer blends, monolayer films, or films. multilayer previously exposed. Double chamber containers can be used in many applications, to house two components separately for later mixing. The components can be liquid or powder. The peelable seal can be created by modifying the sealing conditions so that the peelable seal 76 can be broken by applying a force to a side wall 75 of the container. Normally, one of the chambers will contain a liquid. By exerting pressure on the side walls 75 of the container over the chamber containing the liquid, the liquid contents circulate towards the peelable seal 76 and when sufficient pressure is applied the seal 76 ruptures, allowing the components stored in it to mix. the separate chambers.

Although Figure 6 shows only one peelable seal 76, it is contemplated that multiple peelable seals may be provided to create multiple chambers. Furthermore, Figure 6 shows the peelable seal running between the side edges. It is also contemplated that the peel seals may extend between the longitudinal edges or simply around an area that does not intersect the permanent peripheral bond line 79 to define a chamber.

The peelable seal 76 may be created at the same time as the peripheral sidewalls are sealed or before or after the permanent peripheral seals are created. The peelable gasket 76 can be obtained by controlling the sealing conditions. Peel seals can be created by applying a lower temperature and pressure than are used to provide the permanent peripheral seal or by shortening the seal times relative to those used to provide the permanent seal or the like. Peel characteristics can be further improved by locally modifying the surface characteristics of the film (corona or other suitable treatment).

ES 2 296 784 T3

It is contemplated that the container may be sealed using ultrasonic welding techniques, conduction heat sealing techniques, and other sealing techniques well known in the art.

SAW. Examples

Examples 1, 5 are comparative examples and do not form part of the claimed invention.

The blends identified in the table below were obtained as a monolayer film using an extrusion process. The film was exposed to electron beam irradiation with an accelerating voltage between 200 Ke-v and 2300 Ke-v for a dose shown in the following table:

<td>Formula</td><td> 1</td><td> 2</td><td> 3</td><td> 4</td><td> 5</td><td> 6</td><td> 7</td><td> 8</td><td> 9</td>

<td>Engage Du Pont / Dow</td><td> 100</td><td> 95</td><td> 90</td><td> 80</td><td></td><td></td><td></td><td></td><td> 70</td>

<td> 8003</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td>

<td>Dow Affinity PL-1880</td><td></td><td></td><td></td><td></td><td> 100</td><td> 95</td><td> 80</td><td> 70</td><td></td>

<td>Exxon</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td>

<td>PP3505G</td><td></td><td> 5</td><td> 10</td><td> 20</td><td></td><td></td><td></td><td></td><td></td>

<td>E1</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td>

<td>Montell SA-861</td><td></td><td></td><td></td><td></td><td></td><td> 5</td><td> 20</td><td> 30</td><td> 20</td>

<td>Montell SG-982</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td> 10</td>

<td>Grade of</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td>

<td>autoadh.</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td>

<td>100 kGy</td><td> 1</td><td> 2</td><td> 3,7</td><td> 4</td><td> 1</td><td>NA</td><td> 2</td><td> 4</td><td>NA</td>

<td>150 kGy</td><td> 1</td><td> 2</td><td> 4,5</td><td> 5</td><td> 1</td><td>NA</td><td> 2,3</td><td> 3,3</td><td>NA</td>

<td>200 kGy</td><td> 1</td><td> 3,3</td><td> 4,7</td><td> 5</td><td> 1</td><td> 1,7</td><td> 2</td><td> 4</td><td>NA</td>

<td>Adhes. to</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td>

<td>overbag</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td>

<td>100 kGy</td><td>Y</td><td>S</td><td>N</td><td>N</td><td>Y</td><td>NA</td><td>S</td><td>N</td><td>NA</td>

<td>150 kGy</td><td>Y</td><td>S</td><td>N</td><td>N</td><td>Y</td><td>NA</td><td>N</td><td>N</td><td>NA</td>

<td>200 kGy</td><td>Y</td><td>S</td><td>N</td><td>N</td><td>Y</td><td>NA</td><td>N</td><td>N</td><td>NA</td>

ES 2 296 784 T3

<td>Creep to</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td>

<td>120 ° C%</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td>

<td>0 kGy</td><td>NA</td><td>NA</td><td>NA</td><td>NA</td><td>NA</td><td>NA</td><td>NA</td><td> 550</td><td>NA</td>

<td>100 kGy</td><td> 200</td><td> 138</td><td> 88</td><td> 41</td><td> 263</td><td>NA</td><td> 98</td><td> 28</td><td>NA</td>

<td>150 kGy</td><td> 63</td><td> 38</td><td> 31</td><td> 18</td><td> 43</td><td>NA</td><td> 25</td><td> 13</td><td>NA</td>

<td>200 kGy</td><td> 25</td><td> 13</td><td> 16</td><td> 16</td><td> 21</td><td> 22</td><td> 9</td><td> 22</td><td>NA</td>

<td>Sterilized.</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td>

<td>in</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td>

<td>autoclave</td><td>NA</td><td>NA</td><td>Y</td><td>Y</td><td>NA</td><td>NA</td><td>Y</td><td>Y</td><td>Y</td>

<td>100 kGy 150 kGy</td><td>NA</td><td>NA</td><td>Y</td><td>Y</td><td>NA</td><td>NA</td><td>Y</td><td>Y</td><td>Y</td>

<td>Internal mist (ASTM D1003)</td><td> 1</td><td> 1,2</td><td> 1,6</td><td> 2,8</td><td> 2,7</td><td> 2,7</td><td> 4,3</td><td> 4,8</td><td> 2,2</td>

<td>Module</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td>

<td>tension</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td>

<td>(psi)</td><td> (286)</td><td> (3800)</td><td> (6650)</td><td> (1626)</td><td> (6110)</td><td>NA</td><td> (1981)</td><td> (2882)</td><td> (210)</td>

<td>(ASTM</td><td> 0</td><td></td><td></td><td> 0</td><td></td><td></td><td> 0</td><td> 0</td><td> 60</td>

<td>D882)</td><td> 2,0</td><td> 26,2</td><td> 45,9</td><td> 11,2</td><td> 42,1</td><td> —</td><td> 13,7</td><td> 19,9</td><td> 1,4</td>

<td>MPa</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td>

<td colspan="2">Dow Affinity PL 188</td><td>0 is a U</td><td colspan="7">LDPE with a density of 0.902 g / cc.</td>

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