KR100631389B1 - Non-PVC tube for medical treatment - Google Patents

Abstract

The present invention relates to a non-PVC based medical tube excellent in heat resistance, transparency, flexibility and heat sealing. More specifically, the present invention relates to an outer layer composed of propylene-based alpha olefin copolymer and styrene-ethylene-butylene-styrene terpolymer, propylene homopolymer or propylene-based alpha olefin copolymer or blend thereof And it provides a non-PVC-based medical tube consisting of an inner layer consisting of styrene-ethylene-butylene-styrene terpolymer.

Medical Tube * Propylene * Styrene-Ethylene-Butylene-Styrene * Outer Layer * Inner Layer

Description

Non-PVC tube for medical treatment

The present invention relates to a non-PVC based medical tube excellent in heat resistance, transparency, flexibility and heat sealing. More specifically, the present invention relates to an outer layer composed of propylene-based alpha olefin copolymer and styrene-ethylene-butylene-styrene terpolymer, propylene homopolymer or propylene-based alpha olefin copolymer or blend thereof And it provides a non-PVC-based medical tube consisting of an inner layer consisting of styrene-ethylene-butylene-styrene terpolymer.

In recent years, PVC-based medical fluid containers, which have occupied most of the market, have disappeared due to the generation of endocrine disrupting substances (environmental hormones) and the generation of large amounts of dioxins during incineration. Instead, the development and spread of non-PVC fluid containers of various configurations Is increasing. Along with this, the need for the development of non-PVC-based tubes connected to non-PVC-based fluid containers has emerged.

Accordingly, many developments of polyolefin-based multilayer tubes have been made as non-PVC-based tubes. However, in most cases, the polyolefin-based multilayer tube has a limitation in practical use due to an expensive multilayered structure or lack of heat fusion with a specific polyolefin-based fluid container.

Looking at the prior art of the medical tube, Japanese Patent Laid-Open No. 2004-194803 discloses a resin composition composed of 80 to 20% of propylene resin having 20% or less of C2-C8 alpha olefins and 20 to 80% of styrene elastomer. The medical tube made is described. While the medical tube exhibits excellent flexibility, there is a disadvantage in that the possibility of adhesion to the inner surface of the tube increases when heat-sealed with a polyolefin-based fluid container or sterilization at 121 ° C.

In addition, Korean Patent No. 10-0255283 discloses a coextruded medical grade comprising an outer layer comprising a mixture of a polypropylene copolymer and a styrene-ethylene-butylene-styrene copolymer, a tie layer, and a core layer including polyvinyl chloride. The tube is described. However, the medical tube currently causes environmental hormone problems, and polyvinyl chloride, in which dioxins are generated upon incineration, is used as a core layer to improve flexibility, and a tie layer is used to connect the core layer and the outer layer. There is a problem.

Korean Patent No. 10-0262257 also includes an outer layer comprising a mixture of a polypropylene copolymer and a styrene-ethylene-butylene-styrene copolymer, a tie layer, and a core layer comprising a mixture of a polyamide and ethylene vinyl acetate. A coextruded medical tube is described. However, the tube has a disadvantage of poor transparency, which is a physical property required for medical tubes.

Accordingly, the present inventors have studied to provide a medical tube with excellent heat resistance, transparency, flexibility, heat sealability, and the like, which are required for the medical tube while solving the above disadvantages, and thus, an olefin-based alpha olefin copolymer as an outer layer. And styrene-ethylene-butylene-styrene terpolymers, including propylene homopolymers or alphaolefin copolymers based on propylene or blends thereof and styrene-ethylene-butylene-styrene terpolymers as inner layers When manufacturing a medical tube, it was found that the tube exhibits excellent heat resistance, transparency, flexibility, heat sealability, and the like, thereby completing the present invention.

Accordingly, it is an object of the present invention to provide a medical tube excellent in heat resistance, transparency, flexibility and heat sealing.

In order to achieve the above object, the medical tube of the present invention comprises an outer layer consisting of 40 to 80 parts by weight of an alpha olefin copolymer based on propylene and 20 to 60 parts by weight of styrene-ethylene-butylene-styrene terpolymer; And an inner layer consisting of 10 to 50 parts by weight of a styrene-ethylene-butylene-styrene terpolymer and 50 to 90 parts by weight of an propylene homopolymer or an alphaolefin copolymer having a propylene as a main component or a blend thereof.

Hereinafter, the present invention will be described in more detail.

Medical tube of the present invention has a two-layer structure of the outer layer and the inner layer, the thickness of the inner layer is preferably 10 to 40% of the total tube thickness. If the thickness of the inner layer exceeds 40% of the total tube thickness, the flexibility and transparency of the tube itself is inferior, and if the thickness of the inner layer is less than 10%, the uniform inner layer forming of the tube is difficult, which may cause the inner surfaces of the tubes to stick together during heat sealing. Because of this.

The outer layer of the medical tube of the present invention comprises 40 to 80 parts by weight of propylene-based alpha olefin copolymer and 20 to 60 parts by weight of styrene-ethylene-butylene-styrene terpolymer; Melt index (230 ° C., 2.16 Kg).

The inner layer of the medical tube of the present invention is an inner layer consisting of 10 to 50 parts by weight of styrene-ethylene-butylene-styrene terpolymer and 50 to 90 parts by weight of an propylene homopolymer or an olefin homopolymer or an olefin alphaolefin copolymer or blend thereof; It includes, and has a melt index (230 ℃, 2.16Kg) of 0.5 ~ 10g / 10min.

The lower limit of the melt index of the outer layer and the inner layer is a value that can be actually produced, and when the melt index exceeds 10, the melt tension is low, so that the tube formability is deteriorated.

In the medical tube of the present invention, the outer layer has a melting point (Tm) of 130 to 150 ° C and the inner layer has a melting point (Tm) of 148 to 170 ° C. It is preferable that the melting point of the inner layer is higher than that of the outer layer. This is because, when connecting the fluid container and the tube when heat-sealing by applying a certain temperature and pressure to the inner surface of the fluid container and the outer surface of the tube, the inner surface adhesion does not occur when the melting point of the inner layer is higher than the melting point of the outer layer.

Hereinafter, although an Example and a comparative example are given and this invention is demonstrated in detail, this invention is not limited only to these examples.

First, the materials used in the following Examples and Comparative Examples are summarized as follows.

PP (1): polypropylene random copolymer resin with an ethylene content of 3%, melt index (230 ° C., 2.16 Kg): 2.0 g / 10 min, Tm: 150 ° C.

PP (2): Propylene terpolymer resin having an ethylene and butene-1 content of 3% or more, respectively, melt index (230 ° C., 2.16 Kg): 5.0 g / 10 min, Tm: 135 ° C .;

PP (3): polypropylene homopolymer, melt index (230 ° C., 2.16 kg): 3.0 g / 10 min, Tm: 165 ° C.

SEBS: styrene-ethylene-butylene-styrene terpolymer, melt index (230 ° C, 2.16Kg): 1.0g / 10min, styrene content 30%.

Example 1

70 parts by weight of PP (2) and 30 parts by weight of SEBS were mixed in a Henschel mixer for 3 minutes, and then extruded at 190-220 ° C. with a twin screw extruder having a L / D of 32 and a diameter of 53 mm to obtain a pellet-like composition. The outer layer of the layer tube was used. Meanwhile, 20 parts by weight of the SEBS and 80 parts by weight of the PP (3) were mixed in a Henschel mixer for 3 minutes, and then extruded at 190 to 220 ° C. using a twin screw extruder having a L / D of 32 and a diameter of 53 mm to obtain a pellet-like composition. This was used as the inner layer of the two-layer tube. Next, a two-layer tube having an outer diameter of 8 mm and an outer / inner layer thickness of 800 µm / 200 µm was formed using a two-layer tube molding machine to measure transparency, heat resistance, heat sealability, flexibility, and the like by the following method. The results are shown in Table 1 below.

<Measurement method>

(1) The melt index was measured at 230 ° C. by ASTM D-1238.

(2) Melting temperature was measured by ASTM D-2117 method.

(3) The transparency was measured by ASTM D-746 after cutting the cross section of the two-layer tube into a flat surface.

(4) The bending diameter measured the minimum diameter of the tube when the tube 30cm long was bent slowly with both hands. The smaller the value, the higher the flexibility.

(5) The heat sealability of the two-layer tube was inserted between two non-PVC-based multilayer films, and the appearance was inspected after adhesion for 2 seconds at 135 to 145 ° C and 2Kg pressure.

(6) Heat resistance was measured by change in transparency (%) after steam sterilization at 121 ° C. for 30 minutes.

(7) The moldability was evaluated by the appearance uniformity of the tube, and was measured by the sensory method of whether the surface was smooth and the constant surface form was maintained.

Example 2

50 parts by weight of the PP (2) and 50 parts by weight of SEBS were mixed in a Henschel mixer for 3 minutes, and then extruded at 190-220 ° C. using a twin screw extruder having a L / D of 32 and a diameter of 53 mm to obtain a pellet-like composition. The outer layer of the layer tube was used. Meanwhile, 80 parts by weight of PP (1) and 20 parts by weight of the SEBS were mixed in a Henschel mixer for 3 minutes, and then extruded at 190 to 220 ° C. with a twin screw extruder having a L / D of 32 and a diameter of 53 mm to obtain a pellet-like composition. . This was taken as the inner layer of the two-layer tube, measured in the same manner as in Example 1, and the results are shown in Table 1 below.

Example 3

The outer layer of the tube was changed to 40 parts by weight of PP (1) and 60 parts by weight of SEBS, and the inner layer was changed to 70 parts by weight of PP (3) and 30 parts by weight of SEBS. Except that prepared in / 300㎛, prepared in the same manner as in Example 1 and the results are shown in Table 1 below.

Comparative Example 1

Except that the thickness of the outer / inner layer when forming a two-layer tube in Example 1 to 200㎛ / 800㎛ was tested in the same manner as in Example 1 and the results are shown in Table 1 below.

Comparative Example 2

In Example 1, the outer layer was changed to 30 parts by weight of PP (3) and 70 parts by weight of SEBS, the inner layer was changed to 80 parts by weight of PP (2) and 20 parts by weight of SEBS, and the thickness of the outer / inner layer when forming a two-layer tube was Except that prepared in 700㎛ / 300㎛ was tested in the same manner and the results are shown in Table 1 below.

Comparative Example 3

Example 1 except that the inner layer was changed to 30 parts by weight of PP (1) and 70 parts by weight of SEBS, and the thickness of the outer / inner layer was 700 μm / 300 μm when forming the two-layer tube. Experiments in the same manner as in the results are shown in Table 1 below.

Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Comparative Example 3 Outer layer Resin composition (parts by weight) PP (1) 40 PP (2) 70 50 70 70 PP (3) 30 SEBS 30 50 60 30 70 30 Melt Index (230 ℃, 2.16㎏) 4.0 3.4 1.6 4.0 1.7 4.0 Inner layer Resin composition (parts by weight) PP (1) 80 30 PP (2) 80 PP (3) 80 70 80 SEBS 20 20 30 20 20 70 Melt Index (230 ℃, 2.16Kg) 2.8 1.8 2.7 2.8 4.3 1.2 Outer layer / inner layer thickness (㎛) 800/200 800/200 700/300 200/800 700/300 700/300 % Transparency before sterilization 80 84 84 76 - 82 Heat resistance (121 ℃, transparency after steam sterilization for 30 minutes (%)) 81 85 85 76 - 83 Tube formability ◎ ○ ○ ◎ × △ Bend Diameter of 2-Layer Tube 10 cm 8 cm 9 cm 18 cm - 8 cm Heat seal ◎ ◎ ○ ◎ - Internal Fusion  * ◎: Very good ○: Excellent △: Normal ×: Poor-: No experiment

As described above, the present invention is a medical multilayer using polypropylene-based resin and styrene-ethylene-butylene-styrene terpolymer resin, which is a physical resin required for medical tube, and has excellent heat resistance, transparency, flexibility, and heat sealability. A tube can be provided.

Claims (4)

An outer layer comprising 40 to 80 parts by weight of an olefin-based alphaolefin copolymer and 20 to 60 parts by weight of a styrene-ethylene-butylene-styrene terpolymer; And An inner layer comprising 10 to 50 parts by weight of a styrene-ethylene-butylene-styrene terpolymer and 50 to 90 parts by weight of an propylene homopolymer or an alphaolefin copolymer having a propylene as a main component or a blend thereof; Medical tube consisting of. According to claim 1, wherein the melt index of the outer layer (230 ℃, 2.16Kg) is 2.0 ~ 10g / min, the inner layer melt index (230 ℃, 2.16Kg) is 0.5 ~ 10g / min medical tube, characterized in that . The medical tube according to claim 1, wherein the melting point (Tm) of the outer layer is 130 to 155 ° C, and the melting point of the inner layer is 148 to 170 ° C. The medical tube of claim 1, wherein the inner layer has a thickness of 10 to 40% of the total tube thickness.