KR100720641B1 - Autoclavable Non-Adherent, Heat Sealable Polymer Blends for Fabricating Monolayer and Multiple Layered Films - Google Patents

Abstract

The present invention provides polymer blends for making layers in monolayer or multilayer films. The blend has a first component and a second component. The first component is a group of (1) ethylene and α-olefin copolymers having a density of less than about 0.915 g / dL, (2) lower alkyl acrylates, (3) lower alkyl substituted alkyl acrylates, and (4) ionomers Is selected. The first component should be present in an amount from about 99% to about 55% by weight of the blend. The second component is present in an amount from about 45% to about 1% by weight of the blend and comprises (1) a propylene containing polymer, (2) a polybutene polymer, (3) a polymethylpentene polymer, (4) a cyclic olefin containing polymer And (5) at least one polymer in the group of crosslinked polycyclic hydrocarbon containing polymers. The blend has an elastic modulus of less than about 60,000 psi as measured in accordance with ASTM D882 when fabricated into a film, an internal haze of less than about 25% as measured in accordance with ASTM D1003, an internal adhesion rank of greater than about 2, about 5 For films with a thickness of from about mils to about 15 mils (about 0.127 mm to 0.381 mm), the sample creep had a sample creep of less than 150% at 120 ° C. under a load of about 27 psi, and the film was autoclaved for 1 hour at 121 ° And may be heat sealed to a container having a seal that remains intact when it is made.

Polymer Blends Ethylene and α-olefin copolymers, alkyl acrylates, ionomers, propylene containing polymers, polybutene polymers, polymethylpentene polymers, cyclic olefin containing polymers, polycyclic hydrocarbon containing polymers.

Description

Autoclavable Non-Adherent, Heat Sealable Polymer Blends for Fabricating Monolayer and Multiple Layered Films}

FIELD OF THE INVENTION The present invention relates generally to polymer blends for making films, more particularly films that are less deformable during steam sterilization, are non-adhesive, heat sealable, and suitable for making into flexible medical containers. .

In the medical field where the useful agent is collected, processed, stored in a container, transported and finally delivered to the patient by infusion via a tube to obtain a therapeutic effect, the materials used to make the container must have uniquely combined properties. . For example, an optically clear container is required for visual inspection of a solution for particulate contaminants. The material forming the wall must be flexible enough to disintegrate the container wall and introduce a solution without introducing air into the container. The material must maintain its flexibility and toughness over a wide range of temperatures. Some solutions, such as premixed drug solutions, are stored and transported in containers at temperatures such as -25 to -30 ° C. to minimize drug alteration, so the material must maintain its flexibility and toughness at low temperatures. The material must also be functional and unaffected at high temperatures to withstand the heat of steam sterilization, a process that most pharmaceutical liquid containers and nutritional products undergo prior to transport. The sterilization process generally involves exposing the vessel to steam, typically at a temperature of 121 ° C. and a high temperature.

In order to facilitate production into useful articles, the material is preferably sealable using heat seal techniques. Therefore, the material must maintain sufficient thermoplastic to melt upon heating.

Another requirement is to minimize environmental impact on post-use disposal of products made from the material. In the case of landfill products, it is desirable to minimize or avoid the incorporation of low molecular weight leachable components to produce the product. Another advantage is realized using materials that allow for thermal reprocessing of scrap materials produced during manufacture.

For containers that are disposed of by incineration in order to minimize biological hazards, it is desirable to use materials that minimize or eliminate the formation of inorganic acids that are environmentally undesirable and corrosive.

In addition, the material preferably contains no or low content of low molecular weight additives such as plasticizers, stabilizers and the like that can be released into pharmaceutical liquids or biological fluids.

Soft polyvinyl chloride (PVC) is a frequently chosen material for medical bag applications because of its ability to meet various functional requirements. PVC, one of the most cost effective materials for manufacturing devices that meet the above requirements, also provides a clear advantage. However, PVC has many disadvantages in the market. These shortcomings include incompatibility with PVC compounds and certain drugs, interest in chlorine content and their effects on the environment, and PVC's generally increasing negative market awareness. Thus, many materials have been devised to replace PVC. However, most alternative materials are too expensive to be effective and still do not meet all of the above requirements.

Polyolefins and polyolefin mixtures have been developed that meet the many requirements of medical containers and tubing without the disadvantages associated with PVC. Polyolefins are typically suitable for medical applications because of their relatively low extractability to fluids. Most polyolefins are environmentally safe because they do not generate harmful decomposition products during incineration and are suitable for recycling thermoplastics. Many polyolefins are cost effective materials that can provide an economical alternative to PVC. However, there are many obstacles to overcome in order to replace all the desirable properties of PVC with polyolefins.

For example, there are problems in using certain polyolefins to make medical tubing. Such tubing has been found to have poor surface properties that are easily cut, fragmented, or cut when clamping tubing using slide clamps. In addition, certain polyolefins with desirable modulus properties, such as ultra low density polyethylene, have melting points below the temperature reached during the autoclave process.

Crosslinking by chemical agents or by high energy ionizing radiation is well known to increase the heat resistance of the polymer matrix. Chemical crosslinking is a covalent bond across a separating polymer chain that greatly retards the tendency to deform or flow even at high temperatures above the melting point of the polymer. For example, US Pat. No. 4,465,487, assigned to Terumo, discloses a vapor autoclaveable medical container by irradiating ethylene vinyl acetate copolymer at a dose of 50 kGy to 100 kGy with a high energy (2 Mev) electron beam. It is described that the production to obtain a gel content of 50% to 85%. Patent 4,465,487 describes that if the EVA sidewall of the container is investigated to obtain a gel content of at least about 50% before being sealed together (column 4, lines 20-30). Thus, patent 4,465,487 describes irradiating the sidewalls of the container after sealing the container with a pouch with only the vent face remaining unsealed.

Similarly, US Pat. No. 4,453,940 describes the fabrication of medical containers from EVA and other materials. Patent 4,453,940 also describes the step of crosslinking the material with a high energy electron beam to increase the autoclave resistance of EVA. Patent 4,453,940 warns that if crosslinking exceeds 50%, the use of heat seals is impossible (columns 4, lines 27-35).

U.S. Patent No. 4,401,536 describes crosslinking semi-rigid containers made of a blend of polypropylene and EVA or EEA. This patent does not describe the use of ethylene alpha olefins with polypropylene. Irradiation prior to molding also describes the formation of products with poor heat seal aptitude (columns 4, lines 25-28).

U.S. Patent Nos. 4,892,604 and 5,066,290 assigned to the assignee of the present invention describe medical containers having coextruded high density polyethylene skin and core layers of ethylene vinyl acetate copolymers having about 18% vinyl acetate content. After the vessel is manufactured by conventional lion frequency heat sealing, the assembly is subjected to about 100 kGy of ionizing radiation from a high energy beam accelerator of about 5 Mev. The high density polyethylene layer acts as a moisture and gas permeation barrier to maintain various sterile liquid contents at relatively constant concentrations required by various pharmacopoeia around the world. However, there are some obvious serious drawbacks to this material composition: 1) Since the crosslinked EVA layer is sometimes difficult to seal, the container must be manufactured before the crosslinking process in order to make the container with this material composition ( This makes the manufacturing process very inefficient); And 2) the amount of radiation necessary for sufficient crosslinking also releases a significant amount of acetic acid-byproduct upon radiation exposure. Because HDPE provides a barrier to gas permeation, trapped acetic acid can render the fluid contents strong acidic, which can be very undesirable.

U. S. Patent No. 4,643, 926, assigned to W. R. Grace, describes, in certain embodiments, the manufacture of a pharmaceutical liquid container from a multilayer material in which the layer to be heat-sealed is composed primarily of polypropylene. Since polypropylene is well known to undergo chain break when exposed to radiation, the heat seal layer remains thermoplastic and can be heat sealed to a similar surface. Therefore, the entire multilayer film can be heat sealed to withstand autoclaving. However, the complexity of the multilayer construction and the need to incorporate an acid scavenging compound into the film to remove acid by-products during EVA irradiation (see US Pat. No. 5,445,893) makes the process very complex and expensive. do. In addition, because the film is composed of several very different materials, it is very difficult and impractical to rework the edge trim and other film scrap without significantly reducing the optical and mechanical properties.

U. S. Patent 5,055, 328 describes a multilayered differentially crosslinked film in which the heat seal layer contains additional antioxidants to retard the cross linking, thereby facilitating heat sealing after cross linking. Similarly, Canadian Patent No. 1,125,229 describes another differentially crosslinked multilayer film in which the outer layer contains a crosslinking enhancer. However, these structures are all multi-layered and do not focus on the problem of self adhesion during autoclaving.

Sun, US Pat. No. 4,724,176, describes a multilayered, oriented heat shrinkable container having a radially crosslinked outer layer and a noncrosslinked inner seal layer that regulates the irradiation process. The inner and outer layers can be made of EVA copolymer. This container will be unsuitable for containers that are designed to shrink when heat is applied and thus must substantially maintain their entire volume after the autoclave process.

The main object of the present invention is to provide a polymer material which is generally superior to the material known to the inventor, which is known in the art, commercially available or commercially available. Properties of such materials include flexibility, optical clarity for visual inspection, and heat resistance sufficient to withstand steam sterilization processes without significant deformation or magnetic attachment at temperatures below 121 ° C. The material should be non-oriented, non-adhesive and able to be sealed using heat seal techniques. The material should also be substantially free of low molecular weight leachable additives and should also be able to be safely disposed of by incineration without the generation of significant amounts of corrosive inorganic acids. Finally, the material should serve as a cost effective alternative to the various PVC formulations commonly used in medical devices.

U.S. Pat.No. 5,879,768 discloses (A) high pressure low density with a density of (1) at least one homogeneously branched substantially linear ethylene / α-olefin interpolymer 5 to 95% and (2) 0.916 to 0.930 g / dL. 10 to 100% of a mixture of 5 to 95% polyethylene; And (B) 0 to 90% of one polymer selected from the group consisting of ultra low density polyethylene, linear low density polyethylene, high pressure low density polyethylene, ethylene vinyl acetate copolymers and homogeneously branched linear ethylene polymers. A pouch for labeling a flowable material made from a material having is described. The 5,879,768 patent does not describe the exposure of the blend to radiation and does not describe the blending of homogeneously branched, substantially linear ethylene / a-olefin interpolymers with polypropylene.

When blending one or more polymers to form an alloy composition, it is difficult to achieve both of the above objectives simultaneously. For example, many alloys exhibit significant light scattering and thus do not meet the purpose of optical transparency. Light scattering intensity (measured by haze) depends on the domain size of the component in the micrometer (μ) range and the proximity of the component's refractive index. In general, the choice of components that can be sufficiently processed to very small domain sizes with a minimum refractive index mismatch is difficult. The present invention is provided to solve these and other problems.

Summary of the Invention

The present invention provides a polymer blend for making a layer in a single layer film or a multilayer film. The blend has a first and a second component. The first component comprises (1) ethylene and α-olefin interpolymers having a density of less than about 0.915 g / dL, (2) ethylene and lower alkyl acrylate interpolymers, and (3) ethylene and lower alkyl substituted alkyl acrylate inters Polymer and (4) ionic polymers commonly referred to as ionomers. The second component is selected from one or more of (1) propylene containing polymers, (2) butene containing polymers, (3) polymethylpentene containing polymers, (4) cyclic olefin containing polymers, and (5) crosslinked polycyclic hydrocarbon containing polymers. do. The first component is present in an amount from about 99% to about 55% by weight of the blend and the second component is present in an amount from about 45% to about 1% by weight.

The blend, when made into a film, has an elastic modulus of less than about 60,000 psi as measured in accordance with ASTM D882, an internal haze of less than about 25% as measured in accordance with ASTM D1003, and self adhesion greater than about 2 as defined below. Rank, weak adhesion or non-adhesion to the overpouch material, and having a sample creep of less than 150% at 120 ° C. under a load of about 27 psi; It may be heat sealed to a container having a seal that remains intact when autoclaved for a period of time.                 

The present invention also provides a non-PVC, non-oriented monolayer film having sufficient heat distortion resistance to withstand steam sterilization conditions. The film is made from a blend of first and second components. The first component comprises (1) ethylene and α-olefin interpolymers having a density of less than about 0.915 g / dL, (2) ethylene and lower alkyl acrylate interpolymers, and (3) ethylene and lower alkyl substituted alkyl acrylate inters Polymer and (4) ionic polymers commonly referred to as ionomers. The second component is selected from one or more of (1) propylene containing polymers, (2) butene containing polymers, (3) polymethylpentene containing polymers, (4) cyclic olefin containing polymers, and (5) crosslinked polycyclic hydrocarbon containing polymers. do. The first component is present in an amount from about 99% to about 55% by weight of the blend and the second component is present in an amount from about 45% to about 1% by weight.

The film has an elastic modulus of less than about 60,000 psi as measured according to ASTM D882, an internal haze of less than about 25% as measured according to ASTM D1003, a self-adhesive rank greater than about 2, as defined below, over pouch Has weak adhesion or non-adhesion to the material and has less than 150% sample creep at 120 ° C. under about 27 psi load, and the film is also intact when the liquid filled container is autoclaved at 121 ° C. for 1 hour. Can be heat sealed with a container having the remaining seal.

The present invention also provides methods of making non-PVC and non-oriented films. The method includes providing first and second components, mixing the first and second components to form a blend, extruding the blend into a film, and exposing the film to electron beam radiation. Include. The first component is (1) ethylene and α-olefin interpolymers with density less than about 0.915 g / dL, (2) ethylene and lower alkyl acrylate interpolymers, and (3) ethylene and lower alkyl substituted alkyl acrylates. Interpolymers and (4) ionic polymers commonly referred to as ionomers. The second component is selected from one or more of (1) propylene containing polymers, (2) butene containing polymers, (3) polymethylpentene containing polymers, (4) cyclic olefin containing polymers, and (5) crosslinked polycyclic hydrocarbon containing polymers. do. The first component is present in an amount from about 99% to about 55% by weight of the blend and the second component is present in an amount from about 45% to about 1% by weight.

The film has an elastic modulus of less than about 60,000 psi as measured according to ASTM D882, an internal haze of less than about 25% as measured according to ASTM D1003, a self-adhesive rank greater than about 2, as defined below, over pouch Has weak adhesion or non-adhesion to the material and has less than 150% sample creep at 120 ° C. under about 27 psi load, and the film is also intact when the liquid filled container is autoclaved at 121 ° C. for 1 hour. Can be heat sealed with a container having the remaining seal.

1 is a cross-sectional view of a single layer film of the present invention.

2 is a cross-sectional view of the multilayer film of the present invention.

3 is a material container made of the film of the present invention.

4 shows I.V. Fluid dosage set.

5 is a peritoneal dialysis vessel and tubing set.

6 is a dual chamber bag with a peelable seal separating the chambers.

The present invention may have many other forms of aspects. Preferred embodiments of the invention are described subject to the description of the invention as being illustrative of the principles of the invention and not to limit the broad aspects of the invention to the illustrated embodiments.

I. Polymer Blends and Monolayer Films Formed therefrom

1 shows a monolayer film 10 of the present invention. The monolayer film 10 is made from a polymer blend having a first component and a second component. The first component comprises (1) ethylene and α-olefin interpolymers having a density of less than about 0.915 g / dL, (2) ethylene and lower alkyl acrylate interpolymers, and (3) ethylene and lower alkyl substituted alkyl acrylate inters Polymer and (4) ionic polymers commonly referred to as ionomers. The first component is present in an amount from about 99% to about 55%, more preferably from about 60% to about 85%, most preferably from about 65% to about 80% by weight of the blend.

The second component is selected from the group consisting of (1) propylene containing polymers, (2) butene containing polymers, (3) polymethylpentene containing polymers, (4) cyclic olefin containing polymers, and (5) crosslinked polycyclic hydrocarbon containing polymers. do. The second component is present in an amount from about 45% to about 1%, more preferably from about 15% to about 40%, most preferably from about 20% to about 35% by weight of the blend.

The film has an elastic modulus of less than about 60,000 psi as measured in accordance with ASTM D882, an internal haze of less than about 25% as measured in accordance with ASTM D1003, a self-adhesive rank of greater than about 2 (defined below), over Weak adhesion or non-adhesion to the pouch material, having a sample creep of less than 150% at 120 ° C. under a load of about 27 psi, and wherein the film is also used when the liquid filled container is autoclaved at 121 ° C. for 1 hour. It can be heat sealed to a container having a seal that remains intact.

The term “interpolymer” as used herein includes random or block copolymers, terpolymers.

Suitable ethylene and α-olefin interpolymers preferably have a density of less than about 0.915 g / cc, as measured according to ASTM D-792, and are typically very low density polyethylene (VLDPE), ultra low density ethylene (ULDPE), and the like. It is called as. The α-olefins should have 3 to 17 carbons, more preferably 4 to 12, most preferably 4 to 8 carbons. In a preferred form of the invention, the ethylene and α-olefin copolymers are obtained using a single site catalyst. Particularly suitable single site catalyst systems are described in US Pat. Nos. 5,783,638 and 5,272,236. Suitable ethylene and α-olefin copolymers are available under the trade name AFFINITY by Dow Chemical Company and under the trade name ENGAGE by Dupont-Dow. Sold under the trade names EXACT and PLASTOMER.

The term "lower alkyl acrylate" means a comonomer of formula                 

In the formula, the R group means alkanes having 1 to 17 carbon atoms. The term "lower alkyl acrylate" includes, but is not limited to, methyl acrylate, ethyl acrylate, butyl acrylate, and the like.

The term "alkyl substituted alkyl acrylate" means a comonomer of formula (2)

Wherein R ₁ and R ₂ are alkanes having 1 to 17 carbon atoms and may have the same number of carbons or different numbers of carbons. Thus, the term "alkyl substituted alkyl acrylate" includes but is not limited to methyl methacrylate, ethyl methacrylate, methyl acrylate, ethyl acrylate, butyl methacrylate, butyl acrylate, and the like. no.

Suitable propylene containing polymers include those selected from the group consisting of homopolymers of polypropylene, copolymers of propylene with at least one comonomer selected from α-olefins having 2 to 17 carbon atoms and terpolymers. Suitable polypropylene copolymers and terpolymers include random or block propylene and ethylene copolymers or random or block propylene / ethylene / butene terpolymers. Suitable propylene and α-olefin copolymers are sold by Montel under the trade names PRO FAX, PRO FAX ULTRA and CATALLOY.

The present invention also contemplates using a blend of propylene containing polymers as the second component of the blend. In a preferred form of the invention, the blend comprises at least a first propylene containing polymer and a second propylene containing polymer. The first propylene containing polymer and the second propylene containing polymer may be selected from propylene homopolymers, copolymers described above, and terpolymers. In a preferred form of the invention, the first propylene containing polymer differs from the second propylene containing polymer in at least one of the two. The first difference is that the first propylene containing polymer should preferably have a melt flow rate about three times larger than the second propylene containing polymer, and more preferably about five times larger. The second difference is that the first propylene containing polymer preferably has a melting point of at least about 5 ° C. higher, more preferably at least about 10 ° C. higher than the second propylene containing polymer. Melting points are measured according to ASTM D3417 (Enthalpies of Fusion and Crystallization of Polymers by Differential Scanning Calorimetry). The first propylene containing polymer can be different from the second propylene containing polymer by the first difference, by the second difference, or both.

Suitable homopolymers and copolymers of cyclic olefins and crosslinked polycyclic hydrocarbons and blends thereof are described in U.S. Pat.Nos. 5,218,049, 5,854,349, 5,863,986, 5, which are incorporated herein by reference in their entireties 5,795,945, 5,792,824 and European Patent Nos. 0 291,208, 0 283,164 and 0 497,567.

In a preferred form of the invention, suitable cyclic olefin monomers are monocyclic compounds having 5 to 10 carbon atoms in the ring. The cyclic olefin may be selected from the group consisting of substituted and unsubstituted cyclopentene, cyclopentadiene, cyclohexene, cyclohexadiene, cycloheptene, cycloheptadiene, cyclooctene, cyclooctadiene. Suitable substituents include lower alkyl, acrylate derivatives and the like.

In a preferred form of the invention, suitable crosslinked polycyclic hydrocarbon monomers have two or more rings, more preferably seven or more carbons. The ring may be substituted or unsubstituted. Suitable substituents include lower alkyl, aryl, aralkyl, vinyl, allyloxy, (meth) acryloxy and the like. Crosslinked polycyclic hydrocarbons are selected from the group consisting of those described in the patents and patent applications included above. Suitable polymers containing crosslinked polycyclic hydrocarbons are sold under the tradename TOPAS by Ticona, under the tradenames ZEONEX and ZEONOR by Nippon Zeon. It is sold under the name CZ resin by Daikyo Gomu Seiko and under the name APEL by Mitsui Petrochemical Company.

In a preferred form of the invention, the film has the following physical properties: (1) an elastic modulus of less than about 60,000 psi as measured according to ASTM D882, and (2) an internal haze of less than about 25% as measured according to ASTM D1003. (3) a self-adhesion rank of greater than about 2, as defined below, (4) non-adhesive to over-pouch material, and (5) sample creep of 150% or less at 120 ° C. under a load of about 27 psi (6) The film can be heat-sealed into a container having a seal that remains intact when the liquid filled container is autoclaved at 121 ° C. for 1 hour.

The film is also flexible enough to produce a flowable material container. The film has an elastic modulus of less than about 60,000 psi, more preferably less than about 40,000 psi, even more preferably less than about 30,000 psi, most preferably less than about 20,000 psi as measured according to ASTM D-882. The flowable material container is in I.V. When in a vessel, it is preferred that the vessel collapses or substantially collapses upon draining so that it is less than about 40,000 psi, more preferably less than about 30,000 psi, even more preferably about 20,000 psi as measured according to ASTM D-882. It should have less than elastic modulus.

For the purposes of the present invention, magnetic adhesion is defined as the tendency of the film to adhere to itself during autoclaving. This property can be determined according to the following test. The film strip is cut into 8 "x 2" (20.32 cm x 5.08 cm) with larger machine direction dimensions. This strip is wound into a tube about 0.5 "(1.27 cm) in diameter and 2" (5.08 cm) long. The wound film is held in place by compressing the film layer together at one end with a paper clip. The tube is then placed in a steam autoclave at 121 ° C. for 30 minutes. The sample is cooled for at least 1 hour. Thereafter, the film is released. The resistance to film unwinding and relative damage were ranked as shown in Table 1 below.

ranking  Observed Results One  The film cannot be released without breaking. 2  The film is difficult to peel off and significant surface damage occurs. 3  There is some resistance to delamination and minor surface damage. 4  Slight resistance to delamination and little or no surface damage. 5  There is no peeling resistance and no surface damage.  The ranking is determined by three or more individuals and is recorded as an average.

The adhesion to the over pouch material is determined by the following qualitative test. A 1 inch (2.54 cm) wide film strip was sealed in a typical over pouch bag (medium density or high density polyethylene). The over pouch bag was then placed in a laboratory autoclave at 252 ° F. (122.2 ° C.) and 24.5 psig gauge pressure for 1 hour. After autoclaving, the bag was cut open and strips removed. If the film is separated from the over pouch without leaving a damage mark on the film surface, a non-adhesive rank N is provided. If the film separation indicates visible damage, a rank (Y) is provided that indicates the presence of stickiness to the over pouch. A ranking S indicating weak adhesion may also be provided.

Creep properties are determined at 120 ° C. by clamping a film strip having a thickness of about 5 mils to about 15 mils (about 0.127 mm to 0.381 mm) in a temperature controlled oven and weighting it to exhibit a stress of about 27 psi. After 40 minutes of loading, the film strip was removed and pre-marked dimensional changes at 1 inch (2.54 cm) intervals were recorded.

The film can be sealed using standard heat seal techniques. Appropriate heat seals are formed when a fluid container such as that shown in FIG. 3 is fabricated from the film by sealing the peripheral edges to define a centrally located fluid chamber. The vessel is filled with water and subjected to standard autoclave sterilization. Proper heat seal remains intact upon completion of the autoclave cycle.

Films of the present invention have a haze of less than about 25%, most preferably less than about 15% as measured according to ASTM D1003. For the purposes of the present invention, the internal haze is defined as the haze measured when both film surfaces are wetted with isopropyl alcohol.

II. Polymer and Film Processing

In order to produce the film of the present invention, the raw materials are fed to the extraction hopper at a predetermined mixing ratio using a weighing feeder. The material is extruded using 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. It is also expected to expose the blend to radiation prior to extrusion. The raw materials may also be premixed prior to extrusion using single screw, twin screw or other compounding methods known to those skilled in the art.

A preferred method of irradiating the film is that it is an electron beam at a beam energy of about 150 Kev-10 Mev, more preferably 200-300 Kev and a dose of about 20 kGys to about 200 kGys, more preferably about 60-150 kGys. To expose. Alternatively, the film can be crosslinked using methods known to those skilled in the art. Crosslinking methods used in the industry include exposure to ionizing radiation (gamma, beta, ultraviolet light, etc.) and compounds (peroxides and condensation reactions).

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

III. Multilayer film

2 shows an example of a multilayer film 20 comprising the above-described single layer of layer 12. In a preferred form of the invention, the monolayer will be a seal layer. Multilayer film 20 may include additional layers 14 or additional blended layers selected from layers such as skin layers, high frequency sensitive layers, water vapor barrier layers, gas barrier layers, scrap layers, seal layers and core layers. .

The skin layer may be added to increase the wear resistance of the film. The skin layer may be an olefin material such as homopolymers and copolymers of propylene and ethylene. The skin layer may be polyester, copolyester, polyamide or copolyamide. The term “copolyester” and the like apply to polyesters synthesized from one or more diols and dibasic acids. Copolyesters as used herein may be characterized as copolymers of polyethers and polyethylene terephthalates. More preferably, the copolyesters used herein are, as reactants, polymeric materials derived from 1,4 cyclohexane dimethanol, 1,4 cyclohexane dicarboxylic acid and polytetramethylene glycol ether or equivalents as described above. Can be characterized as:                 

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

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

Scrap material generated prior to irradiation can be incorporated into one or more layers.

IV. Fluid material container

3 is a flowable material container and in particular I.V. The container 30 is shown. 4 shows I.V. Dosage set 40 is shown and FIG. 5 shows peritoneal dialysis set 50. The present invention contemplates the manufacture of medical tubing from the blends of the present invention. The radiation treatment of the tubing differs from the film due to the increased thickness and rounded shape of the tubing, but it is contemplated that the tubing can be efficiently treated within the radiation energy ranges described above for the film. "Fluid material" means a material that will flow by gravity. Thus, flowable materials include liquid articles and powder or granular articles and the like. The container 30 has a side wall 32 that is placed to fit and defines a chamber 34 for containing a flowable material such as a fluid or granular material and is sealed along the peripheral edge. For containers made only through blow molding or through blow extrusion, the longitudinal edges will be sealed. A vent tube 36 or multiple vent tubes are provided to fill and empty the contents of the vessel 30. Sidewalls and vent pipes can be fabricated from one of the single or multilayer films described above. Surprisingly, medical products made from the films and blends described above can be heat sealed even if the film is irradiated with electron beam radiation.

Heat sealing can be accomplished using standard heat sealing techniques known to those skilled in the art.

V. Peelable Seal Containers in Double Chambers

6 shows a dual chamber vessel 70 having a first chamber 72 and a second chamber 74 separated by a peelable seal 76. The container sidewall 75 is made from one of the aforementioned polymer blends, monolayer films or multilayer films. Dual chamber vessels can be used for many applications, such as housing the two components separately for later mixing. The components may be liquid or powder. The peelable seal can be formed by changing the sealing conditions such that the peelable seal 76 can be broken by applying a force to the side wall 75 of the container. Typically, one of the chambers will contain a liquid. By pressurizing the container sidewall 75 against the chamber containing the liquid, the liquid content flows towards the peelable seal 76 and by applying sufficient pressure the seal 76 is broken to allow mixing of the components stored in the separate chamber. Will make it possible.

Although FIG. 6 shows only one peelable seal 76, it can be expected that many peelable seals are provided to form many chambers. 6 also shows a peelable seal which continues between the side edges. It is also contemplated that the peelable seal may extend between the longitudinal edges or extend around a surface that does not cross the permanent peripheral seam 79 to define the chamber.                 

The peelable seal 76 may be formed simultaneously with or before or after the formation of the permanent peripheral seal. The peelable seal 76 can be formed by adjusting the sealing conditions. The peelable seal may be formed by applying a lower temperature and pressure than that used to provide a permanent peripheral seal or by shortening that time from the sealing time used to provide a permanent seal or the like. Further improvement of the peeling property can be obtained by localized modification of the film surface properties (corona or other suitable treatment).

The vessel may be sealed using ultrasonic welding techniques, heat conducting sealing techniques, and other sealing techniques known in the art.

VI. Example

The blends identified in the table below were made into a single layer film using an extrusion method. The film was exposed to electron beam radiation with an acceleration voltage of 200 Kev to 300 Kev at the doses listed in the following table.

 Produce One 2 3 4 5 6 7 8 9 10  DuPont / Dow Engage 8003 100 95 90 80 70  Dow Affinity PL-1880 100 95 90 80 70  Exxon PP3505GE1 5 10 20  Montel SA-861 5 10 20 30 20  Montel SG-982 10  Self-adhesive rank-100 kGy One 2 3.7 4 One NA One 2 4 NA  150 kGy One 2 4.5 5 One NA 1.3 2.3 3.3 NA  200 kGy One 3.3 4.7 5 One 1.7 2 2 4 NA  Adhesive to over pouch-100 kGy Y S N N Y NA Y S N NA  150 kGy Y S N N Y NA Y N N NA  200 kGy Y S N N Y NA Y N N NA  120 ° C Creep (%) 0 kGy NA NA NA NA NA NA Melting NA 550 NA  100 kGy 200 138 88 41 263 NA 216 98 28 NA  150 kGy 63 38 31 18 43 NA 31 25 13 NA  200 kGy 25 13 16 16 21 22 16 9 22 NA  Autoclaveability 100 kGy NA NA Y Y NA NA NA Y Y Y  150 kGy NA NA Y Y NA NA NA Y Y Y  Interior Blur (ASTM D1003) One 1.2 1.6 2.8 2.7 2.7 3.5 4.3 4.8 2.2  Tensile Modulus (psi) (ASTM D882) 2860 3800 6650 16260 6110 NA 12830 19810 28820 21060   Dow Affinity PL 1880 is a ULDPE with a density of 0.902 g / dl. DuPont Dow Engage 8003 is a ULDPE with a density of 0.885 g / dl. Exon PP305GE1 is a homopolymer of propylene (MFR 440). Montel SA-861 is a propylene and ethylene copolymer (MFR 6.5). Montel SA 982 is a propylene and ethylene copolymer (MFR 100). "NA" means not available.

Claims (103)

A first component selected from the group consisting of (1) ethylene and α-olefin copolymers having a density of less than 0.915 g / dL, and (2) ionomers, present in an amount of 99% to 55% by weight of the blend; And A blend of (1) propylene containing polymers, (2) polybutene polymers, (3) polymethylpentene polymers, (4) cyclic olefin containing polymers, and (5) crosslinked polycyclic hydrocarbon containing polymers. Second component present in an amount from 1% by weight to 1% by weight Including; When made of film, elastic modulus less than 60,000 psi as measured according to ASTM D882, less than 25% internal haze when measured according to ASTM D1003, internal adhesion rank over 2, 5 mils to 15 mils (0.127) mm to 0.381 mm), the film has a sample creep of less than 150% at 120 ° C. under a 27 psi load and the film remains intact when the container is autoclaved at 121 ° C. for 1 hour. Heat-sealed into a container having or heat-sealed, Polymer blends for making layers in monolayer films, or multilayer films. The process of claim 1 wherein the propylene containing polymer consists of a homopolymer of polypropylene and a random and block copolymer and a random and block copolymer of one or more comonomers selected from propylene and an α-olefin having from 2 to 17 carbons. Blend selected from the group. The blend of claim 2 wherein the second component is propylene and an ethylene copolymer having an ethylene content of 1 to 6 weight percent of the copolymer. The blend of claim 2 wherein the second component is a blend of the first propylene containing polymer and the second propylene containing polymer. The blend of claim 4 wherein the first propylene containing polymer has a first melt flow rate and the second propylene containing polymer has a second melt flow rate and the first melt flow rate is three times greater than the second melt flow rate. The blend of claim 4 wherein the first propylene containing polymer has a first melt flow rate and the second propylene containing polymer has a second melt flow rate and the first melt flow rate is five times greater than the second melt flow rate. The blend of claim 4 wherein the first propylene containing polymer has a first melting point and the second propylene containing polymer has a second melting point and the first melting point is at least 5 ° C. higher than the second melting point. The blend of claim 4 wherein the first propylene containing polymer has a first melting point and the second propylene containing polymer has a second melting point and the first melting point is at least 10 ° C. higher than the second melting point. The blend of claim 1 wherein the cyclic olefins have 5 to 10 carbons in the ring. The blend of claim 9 wherein the cyclic olefin is selected from the group consisting of substituted and unsubstituted cyclopentene, cyclopentadiene, cyclohexene, cyclohexadiene, cycloheptene, cycloheptadiene, cyclooctene and cyclooctadiene. The blend of claim 1, wherein the crosslinked polycyclic hydrocarbon has at least 7 carbons. 12. The blend of claim 11 wherein the crosslinked polycyclic hydrocarbon is selected from the group consisting of polycyclic hydrocarbons having 7 or more carbons. The blend of claim 1 wherein the α-olefin has 3 to 17 carbons. The blend of claim 1 wherein the α-olefin has 4 to 8 carbons. The blend of claim 14 wherein the ethylene and α-olefin copolymers are obtained using a single site catalyst. The blend of claim 1, wherein the blend is irradiated. The blend of claim 1, wherein the internal haze as measured according to ASTM D1003 is less than 15%. The blend of claim 16, wherein the irradiated blend receives electron beam radiation in a dose of 20 kGy to 200 kGy. delete 19. The blend of claim 18 wherein the irradiated blend is exposed to oxygen partial pressure below ambient conditions when exposed to electron beam radiation. delete delete delete delete delete delete delete delete delete delete delete delete delete delete The blend of claim 1 wherein the blend is a single layer film. delete delete delete delete delete delete delete delete delete delete delete delete delete delete The blend of claim 35, wherein the film is a irradiated film. delete 51. The blend of claim 50, wherein the irradiated film receives electron beam radiation at a dose of 20 kGy to 200 kGy. delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete

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