JPS62106768A - Resin composition for medical material - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to resin compositions for medical equipment, particularly soft vinyl chloride resin compositions used for infusion storage containers, blood storage containers, blood circuit tubes for artificial dialysis, etc. The present invention relates to a resin composition for medical equipment.

(Prior Art) Medical equipment includes, for example, a blood hanger for transporting and storing blood, an artificial heart-lung machine, and a blood circuit tube for performing dialysis using an artificial kidney for patients with kidney failure. For these equipment. Flexible and does not change in quality
It is required to have properties that do not cause deterioration of the blood or transfer of foreign substances into the blood even if it comes into contact with blood for a long time.

In addition, the tube for the blood circuit. Transparency that allows blood passing through the interior to be observed from the outside, and flexibility that allows it to be freely deformed.
Resilience allows the tube to quickly recover its original shape when clamped or removed from the outside of the tube, allowing blood flow to be stopped or allowed to flow at any time through this operation, and when the tube is wrapped or stacked. A non-adhesive surface is required to prevent tubes from adhering to each other.

For blood hangers and tubes for blood circuits, a composition in which a large amount of a plasticizer such as dioctyl phthalate I- is added to a vinyl chloride resin is used. This composition has flexibility and
Although it is less transparent, during use, small amounts of plasticizers such as dioctyl phthalate are eluted and absorbed and accumulated in the body through the bloodstream. Plasticizers such as dioctyl phthalate are hemolytic and cytotoxic, and have various adverse effects when absorbed into the body.

In order to solve these drawbacks, Japanese Unexamined Patent Publication No. 56-412
No. 40 discloses a mixture of a vinyl chloride resin and an ethylene-vinyl acetate-carbon monoxide copolymer. Japanese Patent Application No. 54-116569 discloses a graft copolymer obtained by graft polymerizing vinyl chloride onto an ethylene-vinyl acetate-carbon monoxide copolymer. These compositions.

Highly transparent, flexible, repellent and non-adhesive.

Also in the cold blood test and cytotoxicity test stipulated by the Japanese Pharmacopoeia's Infusion Container Test Method.

Does not exhibit hemolytic or cytotoxic properties. However, since this composition contains vinyl acetate units, acetic acid removal phenomenon occurs due to heating during molding. The acetic acid desorbed from the copolymerization volume is eluted from the surface of the molded product, reducing the pll. The pH value is
Elution 1 specified in the above test method for plastic containers for infusions
It is close to the lower limit value of the pH item in the course test, and may deviate from this value depending on the molding conditions.

A decrease in the pH value on the surface of the molded article has an adverse effect on the human body because it lowers the pH of circulating blood.

(Problems to be Solved by the Invention) The present invention solves the above-mentioned conventional problems, and its purpose is to solve the problems during molding.

It is an object of the present invention to provide a resin composition for medical equipment that does not cause a decrease in pH due to deacetic acid removal of an ethylene-vinyl acetate-carbon monoxide copolymer. Another object of the present invention is to provide a resin composition for medical equipment that has excellent transparency, flexibility, rebound properties, and non-adhesiveness. Still another object of the present invention is to provide a resin composition for medical equipment that is neither hemolytic nor cytotoxic.

(Means for Solving the Problems) The resin composition for medical equipment of the present invention contains an unplasticized soft vinyl chloride resin and 1,4-butanediol bis(β-aminocrotonate), and thereby The above objectives are achieved.

The unplasticized soft vinyl chloride resin refers to a soft vinyl chloride resin that does not contain any plasticizer such as dioctyl phthalate.

The unplasticized soft vinyl chloride resin used in the composition of the present invention is: (1) a mixture of a vinyl chloride resin and an ethylene-vinyl acetate-carbon monoxide copolymer, or (2) an ethylene-vinyl acetate-M carbonized copolymer. There is a graft copolymer in which vinyl chloride is graft-polymerized.

Examples of the vinyl chloride resin in (2) above include 2.

Besides polyvinyl chloride and chlorinated polyvinyl chloride.

There are copolymers containing at least vinyl chloride units.

The copolymer consists of monomers copolymerizable with vinyl chloride and/or
Alternatively, it can be obtained by reacting a polymer capable of grafting reaction with vinyl chloride. Ethylene is a monomer that can be copolymerized with vinyl chloride.

α-olefins such as propylene; vinyl acetate.

Vinyl esters such as vinyl stearate; vinyl ethers such as methyl vinyl ether and cetyl vinyl ether; vinyl halides such as vinyl bromide and vinyl fluoride; unsaturated acids such as maleic acid and fumaric acid; Saturated acid anhydrides; unsaturated acid esters, etc. In addition, styrene, acrylonitrile, vinylidene chloride, etc. can also be used. An example of a polymer that can undergo a graft reaction with vinyl chloride is chlorinated polyethylene.

Examples include vinyl chloride-ethylene copolymer, ethylene-vinyl acetate copolymer (EVA), and epoxy resin. especially,
Vinyl chloride-ethylene copolymer is preferred. For 100 parts by weight of such vinyl chloride resin, 1 to 180 parts by weight of the ethylene-vinyl acetate-M carbonized copolymer,
It is preferably contained in a range of 5 to 160 parts by weight. The composition of the ethylene-vinyl acetate-carbon monoxide copolymer in the mixture (2) preferably includes 10 to 90 parts by weight of vinyl acetate and 3 to 50 parts by weight of carbon oxide, based on 100 parts by weight of ethylene. It is. Commercially available products include, for example, Elvaloy-741 manufactured by DuPont. Also.

When using a vinyl chloride-ethylene copolymer as the vinyl chloride resin, the content of the ethylene component in the copolymer is 3
-12% by weight, preferably 5-10% by weight, and the degree of polymerization is 700-2900. Preferably 1000-28
It is 00.

The composition of the ethylene-vinyl acetate-carbon monoxide copolymer as the graft trunk molecule in item (2) above preferably includes 10 to 90 parts by weight of vinyl acetate to 100 parts by weight of ethylene;
and - 3 to 50 parts by weight of carbon oxide. The amount of vinyl chloride to be grafted is in the range of 20 to 500 parts by weight based on 100 parts by weight of the ethylene-vinyl acetate-carbon monoxide copolymer. moreover.

α-olefins copolymerizable with vinyl chloride, preferably ethylene, may be simultaneously grafted.

The non-moldable soft vinyl chloride resin thus obtained has excellent transparency, flexibility, rebound properties, and non-adhesiveness. Moreover, it is neither hemolytic nor cytotoxic. By adding 1,4-butanediol bis(β-aminocrotonate) to this vinyl chloride resin, it is possible to reduce the pH caused by deacetic acid of the ethylene-vinyl acetate-carbon monoxide copolymer during molding. The decline is significantly suppressed. 1,4-Butanediol bis(β-aminocrotonate) is a crotonic acid ester compound represented by the following formula.

NH2N1lz H3C-C, Cl1COO (C1+□) 400CIIC
=C-C)13 This 1,4-butanediol bis(β-
Aminocrotonate) is contained in an amount of 0.001 to 1 part by weight, preferably 0.01 to 0.5 part by weight, based on 100 parts by weight of the unplasticized soft vinyl chloride resin. 0
．． If the amount is less than 0.001 parts by weight, the decrease in pH will hardly be suppressed. If it exceeds 1 part by weight, although the decrease in pH is suppressed, other items in the eluate test are affected. 1,4-Butanediol bis(β-aminocrotonate) is used alone or in combination with a stabilizing agent such as magnesium oxide or calcium oxide. Addition of stabilizing aids further suppresses the drop in pH.

The resin composition for medical equipment of the present invention further includes:

In order to improve thermal stability and deterioration resistance, stabilizers and plasticizers may be added within the range that does not cause hemolysis or cytotoxicity. Examples of stabilizers include calcium stearate, zinc stearate, and barium stearate.

Epoxidized soybean oil, dioctyl phthalate, etc. are used as the plasticizer.

(Example) The present invention will be described below with reference to examples.

As the vinyl chloride resin, a vinyl chloride-ethylene copolymer containing 4% by weight of the ethylene component was used. Equal weights of this vinyl chloride resin and ethylene-vinyl acetate-carbon monoxide copolymer were mixed.

Made of non-plastic soft vinyl chloride resin. To 200 parts by weight of this unplasticized soft vinyl chloride resin, 0.05 parts by weight of 1,4-butanediol bis(β-aminocrotonate), 0.02 parts by weight of zinc stearate (stabilizer), large epoxidized 10 parts by weight of soybean oil (plasticizer), 1 part by weight of low molecular weight polyethylene wax, and 1 part by weight of ester wax were blended. Put the mixture into two rolls and heat at 160℃ for 7
The mixture was kneaded for a minute to obtain a rolled sheet with a thickness of 1.5 mm. This was then preheated to 170"C for 3 minutes before being heated to a pressure of 10"C.
Pressing was performed at 0 kg/cal for 3 minutes. After cooling, a pressed sheet with a thickness of 0.41 was obtained. Using this sheet, heat treatment was performed at 121° C. for 60 minutes, and the eluate was taken out, according to the eluate test specified in the Japanese Pharmacopoeia Test Method for Plastic Containers for Infusions. After cooling the eluate to room temperature.

Its phi value, UV absorption spectrum, amount of potassium permanganate reducing substance, etc. were measured. The results and the standard values for the above eluate test are shown in the table below. In the table, Δp++ represents the difference in pl+ values between the test solution and the control test solution.

A graft copolymer obtained by grafting vinyl chloride onto an ethylene-vinyl acetate-carbon monoxide copolymer is used as a non-plastic soft vinyl chloride resin (the content of vinyl chloride in the copolymer is 50% % by weight) was used. For 100 parts by weight of this unplasticized soft vinyl chloride resin, ■ 0.03 parts by weight of 4-butanediol bis(β-aminocrotonate) and 0.1 parts by weight of magnesium oxide (stabilizing agent). ,
Same as Example 1 except that 0.02 parts by weight of zinc stearate (stabilizer), 5 parts by weight of epoxidized soybean oil (plasticizer), 1 part by weight of low molecular weight polyethylene wax and 1 part by weight of ester wax were blended. A press sheet was produced. However, the kneading temperature was 150''C and the pressing temperature was 160°C. Using this press sheet, an eluate test was conducted in the same manner as in Example 1.

The results are shown in the table below.

Comparative example 1 1,4-butanediol bis(β-aminocroto-1
Press Sea 1- was exploded in the same manner as in Example 1, except that .) was not blended. Using this press sea i., an eluate test was conducted in the same manner as in Example 1. The results are shown in the table below.

Comparative Example 2 A pressed sheet was produced in the same manner as in Example 1, except that 1,4-butanediol bis(β-aminocrotonate) was not blended and the pressing temperature was 180'C. Using this press sheet, an eluate test was conducted in the same manner as in Example 1.

The results are shown in the table below.

Comparative Example 3 A press sheet was produced in the same manner as in Example 2, except that 1,4-butanediol bis(β-aminocrotonate) and magnesium oxide were not blended. Using this press sheet, an eluate test was conducted in the same manner as in Example 1.

The results are shown in the table below.

(Effect of the invention) The resin composition for medical equipment of the present invention is thus produced.

During molding, there is no decrease in pill due to deacetic acid removal of the ethylene-vinyl acetate-carbon monoxide copolymer. The molded product has excellent transparency, flexibility, rebound resilience, and non-adhesion, and does not exhibit hemolysis or cytotoxicity. Result 9
The composition of the present invention can be used in medical catheters, blood transfusion and infusion tubes, and! It can be effectively used for medical equipment such as hangs for storing infusion fluids and/or tubes for blood circuits for artificial dialysis.

that's all

Claims (1)

[Scope of Claims] 1. A resin composition for medical equipment containing an unplasticized soft vinyl chloride resin and 1,4-butanediol bis(β-aminocrotonate). 2. The resin composition for medical equipment according to claim 1, wherein the unplasticized soft vinyl chloride resin is a mixture of a vinyl chloride resin and an ethylene-vinyl acetate-carbon monoxide copolymer. 3. Claim 1, wherein the non-plastic flexible vinyl chloride resin is a graft copolymer obtained by graft polymerizing vinyl chloride onto an ethylene-vinyl acetate-carbon monoxide copolymer.
The resin composition for medical equipment as described in 2. 4. The 1,4-butanediol bis(β-aminocrotonate) is added to the unplasticized soft vinyl chloride resin 100.
The resin composition for medical equipment according to claim 1, wherein the resin composition is contained in a range of 0.001 to 1 part by weight based on the weight part.