JP2793871B2 - Molding material for medical equipment and medical equipment using the same - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a molding material for medical instruments excellent in transparency, heat resistance and mechanical strength, and a medical instrument using the same.

(Prior art)

BACKGROUND ART Conventionally, bags and containers made of polypropylene resin have been used as medical infusion containers containing Ringer's solution, Hartmann's solution, and the like. The standard of the infusion container is specified by the Japanese Pharmacopoeia Law, and particularly, transparency is required to be high in order to be able to observe foreign substances in the liquid contents. Although polypropylene resin is not satisfactory in mechanical strength, heat resistance during sterilization, safety and hygiene, etc., it is at a level that can be satisfied to some extent, so it is used as an infusion container, Inadequate in terms.

As a method for improving the transparency of a polypropylene resin, the following or has been proposed.

A method of injection-stretch blow molding of a polypropylene resin, a method of adding a nucleating agent, for example, dibenzylidene sorbitol or di (alkylbenzylidene) sorbitol, to a polypropylene resin and heat molding (JP-A-51-2274).
Nos. 0, 53-117044, 56-30449, 58-225143, etc.).

[Problems to be solved by the invention]

However, although the method proposed above improves the transparency to some extent, it is still insufficient. Further, in the above method, the molded article obtained to generate an odor when the polypropylene resin containing the nucleating agent is heated and formed has an odor, and the nucleating agent is eluted into an infusion solution or the like. Not only do they have safety and health problems, but they also have the disadvantage of impairing long-term transparency.

[Means for solving the problem]

In view of the above-mentioned situation of the prior art, the present inventors have conducted intensive studies to obtain molded articles in which both safety and hygiene problems such as transparency and odor of polypropylene resin molded articles have been improved. By molding a composition containing a specific amount of -methylbutene-1 polymer by a blow molding method or the like, it is possible to solve safety and health problems such as odors, and further improve transparency, heat resistance and mechanical strength. The inventors have found that an improved molded article can be obtained, and have completed the present invention.

That is, the gist of the present invention is that the polypropylene resin
A molding material for medical equipment comprising a polypropylene resin composition containing 0.0001 to 10% by weight of a methylbutene-1 polymer, and 3-methylbutene in a polypropylene resin.
A medical device obtained by molding a polypropylene resin composition containing 0.0001 to 10% by weight of one polymer by an extrusion molding method or a blow molding method.

In the present invention, the higher the crystallinity of the 3-methylbutene-1 polymer used, the greater the effect of improving the optical properties. The melting point or heat of fusion measured by a differential scanning calorimeter is used as one of the measures of the degree of crystallinity.

The 3-methylbutene-1 polymer used in the present invention preferably has a melting point of 300 ° C. or more and a heat of fusion of 9 cal / g or more. Melting point lower than 300 ℃ or heat of fusion 9ca
Those lower than l / g have insufficient optical improvement effect,
Not preferred. More preferably, 3-methylbutene-1
The melting point of the polymer is higher than 303 ° C. and the heat of fusion is 15 cal / g or more, most preferably the melting point is 305 ° C. or more, and the heat of fusion is 16 cal / g or more.

The 3-methylbutene-1 polymer used in the present invention may be a copolymer with another α-olefin having 2 to 18 carbon atoms within a range satisfying the above conditions, but is preferably a homopolymer. It is.

As a catalyst system used for obtaining such a 3-methylbutene-1 polymer, a Ziegler-Natta catalyst that gives a polymer having a particularly high stereoregularity is used.

Such a catalyst is, for example, Japanese Patent Publication No. 54-27871,
These are described in JP-A-55-8451, JP-A-55-8452, JP-A-55-8003, JP-A-55-39165 and JP-A-55-14054.

For example, the aluminum content is an atomic ratio of aluminum to titanium of 0.15 or less, and a solid titanium trichloride catalyst complex containing a complexing agent and an organoaluminum compound or further a third component ether, ester,
A catalyst system comprising an electron donating compound such as an amine or an amide is preferably used. In addition, a magnesium compound-carrying titanium-based catalyst can be used favorably, but the above-mentioned titanium trichloride catalyst complex is preferably used.

Further, in the present invention, in order to further increase the crystallinity of the 3-methylbutene-1 polymer used, preferably, the above aluminum content is 0.15 or less in an atomic ratio of aluminum to titanium. And 3-methylbutene-1 in the presence of a catalyst comprising a solid titanium trichloride catalyst complex containing a complexing agent and an organoaluminum compound or further an electron-donating compound in an amount of 10 g per 1 g of the solid titanium trichloride catalyst complex. It is preferred to polymerize in an amount exceeding the above.

The amount of 3-methylbutene-1 polymer in the propylene polymer is from 0.0001 to 10% by weight, preferably from 0.0003 to 3% by weight. When the content of the 3-methylbutene-1 polymer is too small, the effect of improving the transparency is insufficient, and when the content of the 3-methylbutene-1 polymer is too large, generation of fish eyes occurs. -Methylbutene-1 polymer itself is not preferred because of problems such as a decrease in transparency and an increase in cost.

The method for producing the 3-methylbutene-1 polymer-containing polypropylene resin composition used in the present invention includes, for example, 1) 3-methylbutene-1 obtained by polymerizing 3-methylbutene-1 using a Ziegler-Natta catalyst or the like. -1 homopolymerization of propylene or copolymerization of propylene with another α-olefin in the presence of the -1 polymer.

2) Propylene is homopolymerized or copolymerized with another α-olefin using a Ziegler-Natta catalyst or the like, and subsequently 3-methylbutene-1 polymerization is performed in the presence of the obtained propylene polymer.

3) A polymer to be a masterbatch is produced by the method 1) or 2), and a homopolymer of propylene or a copolymer of propylene and another α-olefin is mixed.

4) A separately polymerized polymer of 3-methylbutene-1 and a propylene homopolymer or a copolymer of propylene and another α-olefin are mixed.

And the like, but the method 3) is the most preferable method in terms of the balance between performance and productivity.

That is, in the method of polymerizing propylene after the polymerization of 3-methylbutene-1 by the method of 1), the activity or the stereoregularity may decrease during the polymerization of propylene, and the method of 2) Then, after polymerizing a large amount of propylene, a small amount of 3-methylbutene-1 will be polymerized,
Switching of monomers is complicated.

In addition, since it is necessary to produce a polymer containing a 3-methylbutene-1 polymer for each polypropylene grade, particularly when a continuous polymerization plant continuously manufactures each grade, a 3-methylbutene-1 polymer is required. Many problems of contamination with grades that do not need to be included occur.

On the other hand, the above-mentioned problem does not occur in a method in which a propylene polymer masterbatch containing a relatively large amount of the 3-methylbutene-1 polymer is produced and mixed with a propylene polymer produced by a usual method.

In the case of the above 3) method, the content of the 3-methylbutene-1 polymer in the 3-methylbutene-1 polymer-containing polypropylene resin composition produced by the 1) method or 2) method is not particularly limited, It is preferably at most 70% by weight, more preferably at most 50% by weight.

As a mixing method in the 3) method or the 4) method, a general method such as an extruder, a Brabender kneader, or a roll may be used.

In mixing, it is desirable to knead at a temperature within a range that does not cause melting of the 3-methylbutene-1 polymer. 3 above
Examples of the raw material polypropylene resin used as a mixture with the -methylbutene-1 polymer include propylene homopolymer (propylene homopolymer) or propylene and other α-olefin (ethylene or other α-olefin having at most 12 carbon atoms). (Α-olefins) and a random or block copolymer (the copolymerization ratio of ethylene or another α-olefin is at most 15% by weight, preferably 0.1 to 5.0% by weight).

Melt flow rate of the above polypropylene resin (MFR
Abbreviated. ) May be any one used in the field of films, but according to the method of JIS K-7210, 230 ° C, load 2.16 kg.
0.2 ~ 50g / 10min, preferably 0.4 ~
Those having a range of 30 g / 10 minutes are suitably used.

In addition, various additives generally blended in the polypropylene resin, for example, an antioxidant, a lubricant, an antistatic agent, an anti-blocking agent, EP rubber, known polymers such as silica, fillers and the like are appropriately blended as necessary. It is also possible to use.

In the present invention, a bag or a hollow container-shaped medical device is formed by extrusion molding or blow molding using a molding material comprising a polypropylene resin composition containing the above-mentioned 3-methylbutene-1 polymer. To manufacture.

First, the sheet is formed by using an ordinary sheet forming apparatus and forming method such as an inflation forming method using a circular die and a T-die forming method. After the sheet is stretched as desired, the two sheets are stacked and the periphery thereof is formed into a bag shape by heat sealing (heat fusion) or the like. The above-described sheet forming conditions and bag forming conditions from the sheet are the same as the forming conditions used when forming a sheet and forming a bag from the sheet using a normal polypropylene resin.

In the blow molding method, the polypropylene resin composition is preformed into a tube shape by extrusion or injection (this preformed product is called a parison), sandwiched by a mold, and air is blown into the inside to inflate. Any method may be used as long as it can be cooled and solidified, and examples thereof include extrusion blow molding (direct blow molding), injection blow molding (injection blow molding), and injection stretch blow molding (stretch blow molding).

In the extrusion blow molding, a tubular parison (hot parison) is extruded in a molten state from the die at a temperature of 190 to 290 ° C. from the polypropylene resin composition, and then the parison is closed with a mold. Blow molding is performed under the conditions of blowing, resin temperature of 220 to 240 ° C., and stretching (transverse) magnification of 2 to 4 times to produce a hollow container.

In the injection blow molding, the molten resin of the polypropylene resin composition is injected into a mold at a temperature of 190 to 310 ° C. to form a bottomed parison, and then the parison is clamped with a blow mold. Blow air, resin temperature 15
0 to 190 ° C, stretch ratio 1.1 to 1.3 times in longitudinal direction, 1.3 to 2 in transverse direction
Blow molding is performed under double conditions to produce a hollow container.

Further, in the injection stretch blow molding, the molten resin of the polypropylene resin composition is injected into a mold at a temperature of 190 to 290 ° C. to form a bottomed parison, and then, if necessary, preliminarily blown. ~ 150 ° C, stretch ratio 1.2-3.5 times in longitudinal direction (preferably 1.2-2.2 times), 1.
The hollow container is manufactured by stretch blow molding under the conditions of 2 to 6.0 times (preferably 1.5 to 5.0 times). The thickness of the bottomed parison is in the range of 1.5 to 6 mm, and the bottomed parison may be cooled and solidified (cold parison), then reheated to the resin temperature and stretch blow-molded. The parison shape can be maintained without cooling and solidifying the bottom parison, but the parison may be removed from the mold while at least a part of the parison is still in a molten state (hot parison), and stretch blow-molded at the above resin temperature. The stretching blow method is performed by a method combining mechanical longitudinal stretching with a stretching rod and blow stretching (lateral stretching) by blowing air.

〔Example〕

Hereinafter, examples will be described, but the present invention is not limited to the following examples as long as the gist is not exceeded. Physical properties in the following examples were measured according to the following methods.

1) Melt flow rate (MFR) Measurement was performed according to JIS K-7210 (230 ° C, load 2.16 kg).

2) Crystallization temperature (Tc) Measurement was carried out with a DSC2C type differential scanning calorimeter manufactured by Perkin-Elmer Co., Ltd. at a temperature rise / fall speed of 10 ° C./min.

3) Parallel light transmittance The total light transmittance is set to 100 using a Clarity Meter TM-ID type manufactured by Murakami Color Research Laboratory, a spot is applied to the center of each part of the bottle container, and the bottle container is rotated once. Only the straight light beam (parallel light beam) was taken out and the maximum light amount was read to determine the parallel light transmittance (%).

4) Heat resistance The container body was punched out into strips (15 mm x 50 mm), and annealed at 120 ° C for 1 hour in an air oven. Then, after leaving to stand in a constant temperature room at 23 ° C. and 65% for 24 hours, the shrinkage ratio in the height direction ^{* 1} and the circumferential direction ^{* 2} was measured. ^{* 1} ) Longitudinal shrinkage rate of a strip 50mm in height x 15mm in the circumferential direction ^{* 2} ) Longitudinal shrinkage rate of a strip 15mm in height x 50mm in the circumferential direction 5) Strength Punching according to ASTMD1822-63,
The tensile impact strength was measured in the height direction of the container.

6) Odor evaluation method Evaluation method 10 g of a sample cut into approximately 5 mm squares in a 250 cc Erlenmeyer flask
Insert and seal. This is left for 48 hours under the condition of a temperature of 40 ° C. to evaluate the odor.

Determination method of odor Evaluate in 5 steps of 1-5. 1 smells little, 2 smells a little, 3 smells, 4 smells strongly, 5 smells very strongly.

The evaluation was performed by five persons, and the average value was calculated by rounding off 0.2.

7) Dissolution test A dissolution test was carried out in accordance with the plastic container test method for infusion prescribed in the Japanese Pharmacopoeia General Test Method, and a pass or fail was judged.

Example 1 (a) Catalyst Production Example At room temperature, 515 ml of purified toluene was placed in an autoclave having a capacity of 1 and sufficiently purged with nitrogen, and while stirring, 65.1 g (0.5 mol) of n-butyl ether and 94.9 g (0.5 mol) of titanium tetrachloride were added. m
ol) and 28.6 g of diethylaluminum chloride (0.24mo
l) was added to give a brown homogeneous solution. Then, the temperature was raised to 30 ° C. After 30 minutes have passed, raise the temperature to 40 ° C.
It was kept at 40 ° C. for hours. Then 32g of titanium tetrachloride (0.1
7mol) and 15.5g of tridecyl methacrylate (0.058mo
l) was added and the temperature was raised to 98 ° C. After keeping at 98 ° C. for 2 hours, a granular purple solid was separated and washed with toluene to obtain solid titanium trichloride.

(B) Production Example of Resin-1 (Production of Master Batch of Propylene Polymer Containing 3-Methylbutene-1 Polymer) In an induction-stirring autoclave sufficiently substituted with purified argon, 1.2 mmol of diethylaluminum chloride was added at room temperature under an argon seal. Was added, and 700 cc of liquid 3-methylbutene-1 was further charged.

Next, the temperature was raised to 70 ° C., and 91 mg of the solid catalyst component obtained in the catalyst production example was added, and polymerization of 3-methylbutene-1 was performed for 1 hour. Thereafter, 3-methylbutene-1 was purged in its entirety, and then 3 mmol of diethylaluminum chloride and 0.12 mmol of methyl methacrylate were added to adjust the H ₂ pressure to 0.5 kg / cm ^2, and 700 g of propylene was further added to conduct homopolymerization of propylene. Minutes later, propylene was purged, and the catalyst was removed with an isobutanol-n-hexane mixed solvent.
271 g of a propylene polymer composition was obtained, including the methylbutene-1 polymer.

Under the same polymerization conditions, the amount of 3-methylbutene-1 polymer obtained from the experiment in which propylene polymerization was not performed was
It was 10.8 g.

This 3-methylbutene-1 polymer had a melting point of 311 ° C. and a heat of fusion of 20 cal / g.

The 3-methylbutene-1 polymer content in the propylene polymer composition calculated from the yield of the 3-methylbutene-1 polymer was 4.0% by weight.

The MFR of this polymer was 0.27 g / 10 minutes, the melting point was 163.4 ° C, and the crystallization temperature was 126.6 ° C.

(C) Resin Production Example-2 1.27 parts by weight of the polymer obtained in Resin Production Example-1, 0.1 part by weight of calcium stearate as a stabilizer, BHT
0.2 parts by weight of (2,6-di-t-butylhydroxytoluene) and Irganox 1010, an antioxidant manufactured by Ciba Geigy, tetrakis [methylene-3- (3 ', 5'-di-t-
Butyl-4-hydroxyphenyl) propionate] methane (0.08 parts by weight) is mixed with a propylene-ethylene random copolymer (manufactured by Mitsubishi Kasei Corporation, trade name: Mitsubishi Polypro 6200E)
1, a melt flow rate: 3.2 g / 10 min, density 0.894 g / cm ^2,
(Melting point: 135 ° C., crystallization temperature: 95 ° C.), 100 parts by weight, mixed with a Henschel mixer, and granulated into pellets with a 50 mmφ extruder. 3-methylbutene-1 in this resin composition
The polymer content was 0.05% by weight.

(D) Production of Injection Stretch Blow Molding (Biaxial Stretch Blow Molding) Container The pellets obtained in Resin Production Example-2 were subjected to a resin temperature measurement using a biaxial stretch blow molding machine (Aoki Laboratories SB-150III): Surface temperature 20 ° C under the condition of 240 ° C, injection pressure: 60kg / cm ²
And then removed from the mold. The bottomed parison has a stretch diameter of 24.0 mmφ and a stretch body length of 50 mm.
The body thickness is 4.0 mm. Molding conditions include injection time
The mold was taken out of the mold after 7.0 seconds and a cooling time of 2.5 seconds. The temperature of the bottomed parison body was 111 ° C.

The temperature of the torso of the bottomed parison was obtained by measuring the temperature of the parison torso surface using a digital radiation thermometer (manufactured by Chino Corporation, IR-AH type).

Put the obtained hot bottomed parison into the blow mold,
A stretching rod is introduced into the bottomed parison and stretched in the vertical direction by pressing the bottom of the bottomed parison. Near the end of the vertical stretching, a compressed air of 10 kg / cm ² is blown in for 5 seconds to form a biaxially stretched bottle. did. The temperature of the blow mold at this time was 15 ° C. After the blow was completed, the mold was cooled and taken out of the blow mold.
The obtained bottle is about 80 mm in height and about 60 mm in thickness.
It is of φ. The thickness was about 0.3 mmt in the thickness of the trunk.

The obtained bottle was evaluated for transparency (parallel light transmittance), heat resistance, dissolution test and odor. Table 1 shows the results.

Examples 2 to 6 The same procedure was performed as in Example 1 except that the blending amount of the 3-methylbutene-1 polymer and the injection stretch blow molding conditions were changed to the conditions shown in Table 1. Table 1 shows the results.

Comparative Examples 1 to 3 The same procedure was performed as in Example 1 except that the injection-stretching blow molding conditions shown in Table 2 were used without adding any 3-methylbutene-1 polymer. Table 2 shows the results.

Comparative Examples 4 to 6 In Example 1, the 3-methylbutene-1 polymer was changed to a commercially available nucleating agent sibenzylidene sorbitol (trade name Denone YK-1 manufactured by Marubishi Yuka Co., Ltd.), and injection stretching shown in Table 2 was performed. The procedure was the same except that the procedure was performed under blow molding conditions. Table 2 shows the results.

Examples 7 and 8 800 ml of purified n-hexane and then 13.0 mmol of diethylaluminum chloride were added at room temperature under a blanket of argon to a 2 induction stirring autoclave sufficiently substituted with purified argon.
l and 4000 mg of the solid catalyst component obtained in Catalyst Production Example 1 were added, and the temperature was raised to 70 ° C. Where 3-methylbutene-1
And 3-methylbutene-1 at 70 ° C. for 30 minutes.
Was polymerized.

Thereafter, unreacted 3-methylbutene-1 was purged and washed with purified n-hexane.

The amount of 3-methylbutene-1 obtained depends on the solid catalyst component.
The weight was 11.0 g / g.

The melting point of this 3-methylbutene-1 polymer was 308 ° C. and the heat of fusion was 16 cal / g.

Next, in an induction stirring type autoclave of 24 sufficiently substituted with purified argon, under an argon seal, at room temperature, 52 mmol of diethylaluminum chloride and methyl methacrylate 1.
7 mmol and purified n-hexane 9 were added, and the H ₂ pressure was 0.3 kg / cm ^2.
And Next, the temperature was raised to 70 ° C., and the catalyst component obtained above was
1330mg introduced as Ti catalyst component, propylene pressure is 6kg / cm
Propylene was homopolymerized by adding propylene so as to become ² , propylene was purged after 4.5 hours, and the catalyst was removed with an isobutanol-n-hexane mixed catalyst.
4890 g of a propylene polymer composition including the 3-methylbutene-1 polymer was obtained.

The 3-methylbutene-1 polymer content in the propylene polymer composition was 0.299% by weight.

Then, in Resin Production Example-2, 1 part by weight of the polymer (Example 7) or 0.16 parts by weight (Example 8) is used instead of 1.27 parts by weight of the polymer obtained in Resin Production Example-1. Except for the above, a resin composition of a propylene-ethylene random copolymer was obtained in the same manner as in Resin Production Example-2.

Injection stretch blow molding was performed using the resin obtained here, and molding was performed under the same molding conditions as in Example-2.

 Table 1 shows the results.

[Effects of the Invention] Molded articles such as bags and hollow containers (bottles) obtained by molding using the polypropylene resin composition of the present invention are excellent in transparency, heat resistance, mechanical strength, safety and health, and the like. It is suitably used as medical equipment such as infusion bags and containers.

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Hidehito Kato 3-10, Shiodori, Kurashiki-shi, Okayama Prefecture Inside the Mizushima Plant of Mitsubishi Kasei Co., Ltd. (72) Inventor Masayuki Arai 3-10, Shiodori, Kurashiki-shi, Okayama Mitsubishi Inside the Mizushima Plant of Kasei Co., Ltd. (58) Field surveyed (Int. Cl. ⁶ , DB name) C08L 23/10 C08L 23/20

Claims (2)

(57) [Claims] 1. A polypropylene resin comprising 3-methylbutene-
A molding material for medical equipment comprising a polypropylene resin composition containing 0.0001 to 10% by weight of one polymer. 2. A polypropylene resin comprising 3-methylbutene-
A medical device obtained by molding a polypropylene resin composition containing 0.0001 to 10% by weight of one polymer by an extrusion molding method or a blow molding method.