WO2012169081A1

WO2012169081A1 - Vinyl chloride resin composition

Info

Publication number: WO2012169081A1
Application number: PCT/JP2011/066184
Authority: WO
Inventors: 昂次坂井
Original assignee: リケンテクノス株式会社
Priority date: 2011-06-09
Filing date: 2011-07-15
Publication date: 2012-12-13
Also published as: JP2012255104A

Abstract

Provided is a plasticizer-containing vinyl chloride resin composition, the composition having low plasticizer migration and volatility, and hence being useful for medical tubing, medical bags, and other forms of medical equipment. The vinyl chloride resin composition comprises 100 weight parts of vinyl chloride resin and 10-90 weight parts of di-(2-ethyl hexyl)isophthalate.

Description

Vinyl chloride resin composition

The present invention relates to a vinyl chloride resin composition. More specifically, the present invention relates to a vinyl chloride resin composition that is flexible and has low component leaching and volatility, and is therefore suitable for medical instruments such as medical tubes and medical bags.

Medical devices such as medical tubes such as catheters and medical bags such as blood bags, drug solution bags, and drain bags are used in terms of moldability, adhesiveness, processability, heat resistance, kink resistance, and low cost. Therefore, those made of soft vinyl chloride resin are the most common. Soft vinyl chloride resin should be melt kneaded by adding plasticizers to vinyl chloride resin to add properties such as flexibility, elasticity and cold resistance, and blending various additives such as stabilizers as necessary. Is obtained. As the plasticizer, phthalate esters such as di-2-ethylhexyl phthalate (hereinafter abbreviated as DEHP) have been used. However, DEHP is likely to ooze and volatilize from a soft vinyl chloride resin (for example, Patent Document 1). Therefore, when such a plasticizer is used for a medical tube or a medical bag, there are problems as described below.

Medical tubes are inserted endoscopically into blood vessels, gastrointestinal tract, urethra, trachea, etc., and used for assisting physiological function, diagnosis, examination, physiological function monitoring, nutritional supplementation, blood transfusion, body fluid management, etc. It is widely used for life support and treatment. In practice, in order to perform various medical procedures safely and reliably, for example, a connection tube, which is a kind of medical tube, is connected to a medical solution bottle or other instrument through various medical connectors. Here, if the plasticizer contained in the soft vinyl chloride resin that constitutes the connection tube is likely to ooze out, the oozed plasticizer will permeate (move) into the connector in contact with the connection tube, As a result, there is a problem that a crack is generated in the connector.

In addition, sterilization is indispensable for medical devices. If the plasticizer has high volatility, the plasticizer volatilizes when it is sterilized with steam or hot water, such as heat sterilization, and the flexibility is impaired. There is.

Therefore, soft vinyl chloride resins containing 2-ethylhexyl trimellitic acid (TOTM) or diisononylcyclohexane-1,2-dicarboxylate (DINCH) as plasticizers other than DEHP have been proposed (for example, Patent Documents 2 to 4). ). However, plasticizer migration and volatility issues remain. In addition, the soft vinyl chloride resin is further blended with an epoxidized vegetable oil. When the plasticizer is TOTM, when the epoxidized vegetable oil is blended, a component contained in the soft vinyl chloride resin, for example, a stabilizer. And the like are likely to be eluted (Comparative Examples 10 to 12).

Furthermore, a polyester plasticizer has been proposed as a plasticizer with low migration (for example, Patent Document 5). However, this plasticizer has a problem that plasticization efficiency is poor and a large amount of plasticizer must be blended in order to obtain predetermined flexibility and hardness.

JP-A-63-218750 Japanese Patent Laid-Open No. 2005-230058 JP 2005-40397 A JP 2006-61226 A Japanese Patent Laid-Open No. 10-101777

The present invention has been made in view of the above circumstances, and the object thereof is a vinyl chloride resin composition, which has no problem of migration and volatility, and therefore is suitable for medical instruments such as medical tubes and medical bags. It is to provide a vinyl chloride resin composition that is suitable.

The present inventor has found that the above object can be achieved when di (2-ethylhexyl) isophthalate is added as a plasticizer to a vinyl chloride resin.

That is, the present invention is a vinyl chloride resin composition comprising 100 parts by weight of vinyl chloride resin and 10 to 90 parts by weight of di (2-ethylhexyl) isophthalate. The present invention also provides a medical device comprising the vinyl chloride resin composition.

The vinyl chloride resin composition of the present invention has low plasticizer migration and volatility, and is therefore suitably used for medical instruments such as medical tubes and medical bags.

Hereinafter, the vinyl chloride resin composition of the present invention will be described in detail. The vinyl chloride resin composition of the present invention contains 100 parts by weight of vinyl chloride resin and 10 to 90 parts by weight of di (2-ethylhexyl) isophthalate.

Vinyl chloride resin refers to all polymers having a group represented by —CH ₂ —CHCl—, such as vinyl chloride homopolymer and ethylene-vinyl chloride copolymer, etc. except vinyl chloride and vinyl acetate. Similar to vinyl chloride resin, such as copolymers with other polymerizable monomers, and post-chlorinated vinyl copolymers, homopolymers and copolymers modified, and chlorinated polyethylene, etc. Includes chlorinated polyolefins.

The vinyl chloride resin preferably has a number average degree of polymerization of 300 or more and 7000 or less, more preferably 500 or more and 2000 or less. These vinyl chloride resins can be used alone or in combination of two or more as the vinyl chloride resin component in the vinyl chloride resin composition of the present invention.

Di (2-ethylhexyl) isophthalate is a compound represented by the following formula.

The di (2-ethylhexyl) isophthalate is commercially available.

The addition amount of the di (2-ethylhexyl) isophthalate is 10 to 90 parts by weight, preferably 20 to 80 parts by weight, and more preferably 20 to 65 parts by weight with respect to 100 parts by weight of the vinyl chloride resin. If it is less than the above lower limit, the flexibility may be insufficient, and if it exceeds the above upper limit, the strength may remarkably decrease or bleed.

The vinyl chloride resin composition of the present invention may further contain an epoxidized vegetable oil. Epoxidized vegetable oil can impart flexibility and heat resistance. Examples of the epoxidized vegetable oil include epoxidized soybean oil (ESBO) and epoxidized linseed oil.

The addition amount of the epoxidized vegetable oil is 1 to 100 parts by weight, preferably 2 to 30 parts by weight, more preferably 2 to 10 parts by weight with respect to 100 parts by weight of the vinyl chloride resin. If it is less than the above lower limit, the effect of imparting heat resistance may not be obtained. Moreover, if the upper limit is exceeded, bleeding may occur.

Furthermore, the vinyl chloride resin composition of the present invention may contain a polyester plasticizer as long as the object of the present invention is not impaired.

In addition, the vinyl chloride resin composition of the present invention may be blended with a stabilizer usually used for soft vinyl chloride resins for food use and medical use. Examples of the stabilizer include barium-zinc and calcium-zinc stabilizers. The addition amount of the stabilizer is preferably 0.1 to 10 parts by weight with respect to 100 parts by weight of the vinyl chloride resin. When the added amount of the stabilizer is less than 0.1 parts by weight, the effect as a stabilizer is small, and even when added over 10 parts by weight, the effect of increasing the amount is not recognized.

In the vinyl chloride resin composition of the present invention, a vinyl chloride resin and di (2-ethylhexyl) isophthalate, together with optional components if necessary, are put into a pressure kneader, and the resin temperature is 150 to 160 ° C. for 5 to 10 minutes. It can be obtained by melt-kneading.

The vinyl chloride resin composition of the present invention can be suitably used for various medical instruments such as medical tubes, medical bags, and respiratory masks because of its low plasticizer migration and volatility. Examples of medical tubes include tube feeding tubes, hemodialysis tubes, respiratory tubes, catheters, pressure monitor tubes, and heparin tubes. Examples of the medical bag include a blood bag, a chemical solution bag, and a drain bag.

Examples The present invention will be described in more detail with reference to examples. However, the present invention is not limited to these examples.

Examples 1 to 5 and Comparative Examples 1 to 9
The components (parts by weight) shown in Table 1 were melt-kneaded at about 160 ° C. using a pressure kneader to produce a vinyl chloride resin composition, which was passed through a roll to form a sheet. Next, the sheet was molded into a predetermined size with a press machine to obtain a test piece, and the following tests (2) and (3) were performed.

In addition, the symbol in Table 1 shows the following.
-PVC: Vinyl chloride resin (average polymerization degree = 1300)
・ DOIP: Di (2-ethylhexyl) isophthalate ・ DOP: Di (2-ethylhexyl) phthalate ・ DINP: Diisononyl phthalate ・ DOTP: Di (2-ethylhexyl) terephthalate ・ n-DOP: Di-n-octyl phthalate ・ DPHP : Di (2-propylheptyl) phthalate • DIDP: Diisodecylphthalate • TOTM: Tri (2-ethylhexyl) trimellitate • DOA: Di (2-ethylhexyl) adipate • DINCH: Diisononylcyclohexane-1,2-dicarboxylate ESBO: Epoxidized soybean oil Stabilizer: Ca-Zn stabilizer

Test (1) Kneading Test The following criteria were used to evaluate the kneaded product for yellowing, odor, and kneadability (gelation rate) when the components were kneaded to produce a vinyl chloride resin composition.
(I) The presence or absence of yellowing was visually evaluated.
○: No yellowing.
X: Yellowing occurred.
(Ii) The presence or absence of odor was evaluated by sensory evaluation.
○: No odor.
X: There is a slight odor.
(Iii) Kneadability (gelation speed)
○: The time until gelation is less than 2 minutes.
X: It takes 2 minutes or more to gel.

(2) Transferability test After preparing a test piece having a size of 20 mm in length × 30 mm in width × 1 mm in thickness and measuring its weight, the test piece is sandwiched between two transition plates 130 mm in length × 130 mm in width × 2 mm in thickness. Further, it was sandwiched between glass plates and a load of 1 kg was applied. The test piece is placed in a constant temperature and humidity chamber (SE-47CIA manufactured by KATO) adjusted to a temperature of 60 ± 2 ° C. or 80 ± 2 ° C. and a humidity of 70 ± 5% in accordance with JIS K 7100: 1999 and left for 72 hours. Further, after being left in a constant temperature and humidity chamber (temperature: 23 ± 2 ° C., humidity: 50 ± 5%) for 24 hours, the weight of the test piece is measured, and the test piece previously measured before the test is measured. The difference from the weight (weight loss, g) was evaluated according to the following criteria. The results are shown in Table 1. In addition, the PMMA board, the ABS board, the PS board, and the PC board were used as the transition board, and each plate was tested. The PMMA, ABS, PS, and PC are resins usually used for constituting a connector connected to a medical tube or a medical bag.
1: 0.050 g or more 2: 0.010 g or more but less than 0.050 g 3: 0.005 g or more but less than 0.010 g 4: 0.001 g or more but less than 0.005 g 5: less than 0.001 g

(3) Volatility test A test piece having a size of 20 mm long × 30 mm wide × 1 mm thick was prepared, and its weight was measured. Next, the test piece was placed in a constant temperature and humidity chamber (SE-47CIA manufactured by KATO) adjusted to temperature: 80 ± 2 ° C. and humidity: 80 ± 5% in accordance with JIS K 7100: 1999, 24 hours later, 48 hours later The sample was taken out after 720 hours and after being left in a constant temperature and humidity chamber (temperature: 23 ± 2 ° C., humidity: 50 ± 5%) for 24 hours, and then the weight of the test piece was measured to determine the rate of weight reduction. It was. The results are shown in Table 1.

Examples 6 to 8 and Comparative Examples 10 to 12
In Example 1, a composition was produced in the same manner as in Example 1 except that the amounts of plasticizer (DOIP) and ESBO were changed to those shown in Table 2, and test pieces were produced (Examples 6 to 8). Also, compositions were produced in the same manner as in Examples 6 to 8 except that TOTM was used as a plasticizer in Examples 6 to 8, and test pieces were produced (Comparative Examples 10 to 12). The following elution test was performed using the obtained test piece. The results are shown in Table 2.

(4) Elution test The following test was conducted based on "Japanese Pharmacopoeia". 15.00 g of a test piece having a thickness of 1 mm was washed with water and dried at room temperature. This test piece was put into an Erlenmeyer flask having an internal volume of 500 ml, 300 ml of distilled water was added and sealed with a silicone rubber stopper, and heated at 121 ° C. for 60 minutes using a high-pressure steam sterilizer. After decompression, the Erlenmeyer flask containing the test piece was taken out from the autoclave and left to reach room temperature. The test piece was transferred to a 300 ml volumetric flask together with distilled water, and distilled water was added to make exactly 300 ml, which was used as a test solution. Moreover, the test liquid which does not contain a test piece as a blank test liquid was prepared by said method. The following tests (i) and (ii) were performed on the test solution and the blank test solution.

(I) Zinc test
Preparation of dilute nitric acid aqueous solution Dilute nitric acid was prepared in accordance with “Japanese Pharmacopoeia 16th revision”. That is, water was added to 10.5 ml of nitric acid to make 100 ml, which was 10% diluted nitric acid. Furthermore, this was diluted 3 times to make a dilute nitric acid aqueous solution (A).
Preparation of test solution for zinc test 10 ml of the above test solution was put into a 20 ml volumetric flask with a stopper, and then diluted to 20 ml with the diluted nitric acid aqueous solution (A) prepared above was used as the test solution for zinc test. .
Preparation of Zinc Test Reference Solution After 10 ml of the blank test solution was put into a 20 ml volumetric flask with a stopper, the solution was diluted to 20 ml with the diluted nitric acid aqueous solution (A) prepared above, and the zinc test reference solution ( 0 μg / ml). In addition, after diluting a zinc standard solution (1000 ppm) manufactured by Kanto Chemical Co. to a concentration of 1.0 μg / ml in a 20 ml volumetric flask with a stopper, the diluted nitric acid aqueous solution ( The solution made up to 20 ml in A) was used as a standard solution for zinc test (0.25 μg / ml). Similarly, 0.1 μg / ml and 0.5 μg / ml zinc test reference solutions were prepared.
Measurement of zinc content Using an atomic absorption spectrophotometer (manufactured by Shimadzu Corporation, AA-670), the absorbance at a wavelength of 213.9 nm was measured for the above standard solution for zinc test. An amount of zinc contained in 1 ml of the test solution (μg / ml) is obtained by drawing a calibration curve from the measured value of the reference solution and comparing this with the result of measuring the test solution for zinc test in the same manner as described above. Asked.

(Ii) UV Absorbance Measurement Solution Take the blank test solution prepared above in a quartz cell with a thickness of 10 mm, correct the UV-visible spectrophotometer (U-3010, manufactured by Hitachi, Ltd.), and then perform the test prepared above. Similarly, the liquid was placed in a quartz cell, and the absorbance at a wavelength of 220 to 350 nm was measured with the same tester to obtain the maximum value. A larger maximum value means more eluate from the test piece.

As is apparent from Table 2, the vinyl chloride resin compositions of Examples 6 to 8 using DOIP as a plasticizer have a small amount of eluate even when ESBO is added, and even if the amount of ESBO is increased. The amount of eluate did not change. On the other hand, the compositions of Comparative Examples 10 to 12 using TOTM as the plasticizer had a larger amount of the eluate than the compositions of Examples 6 to 8, and the more the amount of ESBO, the greater the amount of the eluate. There were many.

Claims

A vinyl chloride resin composition comprising 100 parts by weight of a vinyl chloride resin and 10 to 90 parts by weight of di (2-ethylhexyl) isophthalate.
The vinyl chloride resin composition according to claim 1, further comprising 1 to 100 parts by weight of epoxidized vegetable oil.
A medical instrument comprising the vinyl chloride resin composition according to claim 1.
The medical instrument according to claim 3, which is a medical tube or a medical bag.