JPH02229848A - Radiation-resistant resin composition - Google Patents

Abstract

PURPOSE:To obtain a composition, extremely effective in preventing discoloration with exposure to radiation by blending a vinyl chloride-based resin with an epoxidized vegetable oil, calcium and zinc salts of organic carboxylic acids and a thioalcohol compound. CONSTITUTION:A composition obtained by blending 100 pts.wt. vinyl chloride- based resin with 0.5-30 pts.wt. epoxidized vegetable oil, 0.01-3 pts.wt. calcium and zinc salts of organic carboxylic acids and 0.01-5 pts.wt. thioalcohol compound. For example, the resin is blended with epoxidized soybean oil, calcium caproate octyl mecaptan, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a vinyl chloride resin composition having excellent resistance to radiation, particularly gamma rays.

Molded products made of vinyl chloride resin are sterilized and used for medical equipment such as syringes and blood bags, as well as packaging materials.

[Conventional technology]

As a method for treating role bacteria. Conventionally, sterilization has been carried out by boiling or ethylene oxide gas. However, the boiling method is not suitable for resins that are unstable to heat, and the method using mataethylene oxide cannot necessarily be said to be a good sterilization method due to problems with gas toxicity and permeability. As an alternative to these methods, low temperature. Dry method. A method of sterilization using gamma rays has been proposed, which is relatively inexpensive. However, in order to prevent discoloration of the resin due to γ rays, for example,
Although a vinyl chloride resin composition for gamma ray sterilization is proposed in the publication, it is still insufficient.

[Problem that the invention seeks to solve]

Therefore, in order to prevent discoloration of resins due to γ rays, known antioxidants such as hindered phenol compounds, hindered amine compounds, and dialkylthiodicarboxylic acid esters have been used, but they are not sufficient to prevent discoloration due to radiation irradiation. , efforts have been made to add other compounds to the above antioxidants. However, to date, satisfactory quality and performance have not been obtained.

[Means to solve the problem]

As a result of intensive research, the inventors of the present invention found that vinyl chloride resin, epoxidized vegetable oil, and calcium salt of organic carboxylic acid. The inventors have discovered that a resin composition containing a PA-containing carboxylic acid zinc salt and a thioalcohol compound is effective in preventing discoloration caused by radiation irradiation, leading to the present invention.

That is, the present invention relates to a radiation-resistant resin composition comprising a vinyl chloride resin, an epixylated vegetable oil, an organic carboxylic acid calcium salt, an organic carboxylic acid zinc salt, and a thio7/L/cole compound.

The vinyl chloride resin used in the present invention is not limited to a vinyl chloride homopolymer, but may also be a vinyl chloride copolymer. As a copolymer of vinyl chloride. It is also possible to use a copolymer obtained by copolymerizing vinyl chloride with another monomer 7, or a graft polymer obtained by graft polymerizing vinyl chloride with another polymer or copolymer. can. Other monomers mentioned above include ethylene. α-olefins such as propylene, vinyl acetate. Vinyl esters such as vinyl stearate, methyl vinyl ether, heptyl vinyl ether
Vinyl ethers such as 7-l. JI version? vinyl halides, vinyl fluoride, methyl acrylate,
Methyl methacrylate, butyl acrylate, butyl methacrylate, 2-ethylhexyl acrylate,
Acrylic esters and methacrylic esters such as 2-ethylhexyl methacrylate, stearyl acrylate, and stearyl methacrylate. Unsaturated carboxylic acids such as acrylic acid and methacrylic acid, maleic acid. Examples include unsaturated dicarphonic acids such as maleic anhydride and fumaric acid and their esters, styrene, acrylonitrile, and vinylidene chloride.

Examples of the main polymer or copolymer of the graft copolymer include chlorinated polyethylene, ethylene-vinyl acetate copolymer, and ethylene-propylene copolymer. Furthermore, chlorinated vinyl chloride resin obtained by post-chlorinating vinyl chloride resin can also be used.

The epoxidized vegetable oil used in the present invention includes: Examples include epoxidized soybean oil, oxidized linseed oil, epoxidized mustard oil, etc. The amount of epoxidized vegetable oil added is 0.5 to 30 parts by weight per 100 parts by weight of vinyl chloride resin. .

The organic carboxylic acids constituting the organic carboxylic acid calcium salt and the organic carboxylic acid zinc salt include 7°uronic acid, belargonic acid, and lauric acid. 2-Ethylhexylic acid, myristic acid, valmitic acid, untesylenic acid, ricinoleic acid, linoleic acid, linoleic acid, neodecanoic acid, oleic acid, stearic acid. Isodecanoic acid, instearic acid, 12-hydroxynudearic acid, alkinoic acid, pehenic acid, erucic acid. Pracisic acid and mixtures of the above naturally occurring acids such as tallow fatty acids, coconut oil fatty acids;
benzoic acid. Examples include toluic acid and tertiary butylbenzoic acid. The appropriate amount of the calcium salt and zinc salt of these organic carboxylic acids to be added is 0.01 to 3 parts by weight per 100 parts by weight of the vinyl chloride resin.

Furthermore, the thioalcohol' compound added in the present invention is
It is extremely effective in preventing discoloration and discoloration of resins for medical equipment when medical equipment is sterilized by irradiation with radiation, and the amount added to 100 parts by weight of vinyl chloride resin is 0.01 to 5M.
The quantity is appropriate. Examples of thioalcohol compounds include octylmerbutane, decylmerbutane, and dodecylmercaptane. Tetradecyl mercabutane, hexadecyl mercabutane, octadecyl mercabutane. 1
．． 2-dimercaptoethane, l,2-dimercaptopropane, 1,3-dimercaptopropane, 1,4-dimercaptobutane, 1,6-dimercapto-7'tohexane, 1.
8-dimercaptooctane, 1.10-dimercaptooctane
Todecane, 2-mercaptoethanol A/, 2-mercapto-2,2-dimethylethanol, 1-mercapto-2
-probanol, 2-mercap}-1,3-propanediol, 3-mercapto-1,2-propanediol,
1,3-dimercapto-2-1-mouth Ivanoμ,2,3
-dimercapto-1-probanol. 4-Merkagut-
1.3-butanediol, 1.4-dimer-2,
3-butanediol, 4-mercapto-1. 2. 3
-Butane triode/L/, 3-merucadet-1. 2
．． 4-Butanetriol, 2-hydroxybutylmercabutane. 2-Hydroxyhexylmerkafrine, 2-
Hydroxyheptylmer-caftane, 2-hydroxyoctylmer-butane, 2-hydroxydecylmer-butane, 2-hydroxydodecylmer-butane, 2-hydroxytetradecylmer-butane. 2-hydroxyhexadecylmer-cadetane, 2-hydroxyoctadecylmercabutane, 2-hydroxyoleylmer-butane,
2- and droxyricinol mercabutane, 2-hydroxylinol mercabutane, 3-methoxy-2-hydroxyderopyl mercabutane, 3-ethoxy-2-hydroxypropyl mercabutane. 3-Butoxy-2-hydroxypropylbutane, 3-octoxy-2-hydroxyglopylbutane. 3-decyloxy-2-hydroxyprobylbutane, 3-dodecyloxy-
2-hydroxypropylbutane, 3-tetradecyloxy-2-hydroxypropylbutane, 3-
Hexadecy-oxy-2-hydroxyglopyrubutane. 3-octadecyloxy-2-hydroxyglobilmerylbutane, binu(2-hydroxy-3-mercaptobuty) V) ether A/, ethylene glycol bis(
mercaptoacetate), ethylene glycol bis(β
-methacoglopionate), ethylene glycol monomerkabutoacetate, ethylene glycol mono-β-
Mercaptopropionate, propylene glycol bis(mercaptoacetate), propylene glycol bis(β-mercaptopropio*-}). Propylene glycol monomerkabutoacetate, Propylene glycol mono β-mercaptopropionate, 1,4-butanediol bis(mercaptoacetate), 1,4-butanediol bis(/-mercaptogropionate), 1
．． 4-butanediol monomercabutoacetate, 1.
4-Butanediol mono! Ichimehachi Kapto Probio *-}
, l-lyethylene glycol dimerkabutane, trimethylolpropane tris(mercaptoacetate),
Trimethylolpropane bis(methcaptoacetate)
．． Trimethylolpropane monomer Kabutoacetate,
Trimethylolpropane tris (β-mercaptoprobionate), trimethylolpropane bis(β-mercaptopionate), trimethylolpropane 7-β
-Mercaptopropionate, Pentaerythritol Tetrakis (Mercaptoacetate), Pentaerythritol Tris (Mercaptoacetate), Pentaerythritol Bis (Mercaptoacetate), Pentaerythritol Monomercaptoacetate, Pentaerythritol Tetraquine (β-Mercaptophorobionate) ),
Pentaerynuritortris (β-mercaptoderopionate). Pentaerythritol bis(β-mer'cap'propionate), pentaerythritol mono-β-
Mercabutpropionate, diventaerythritol hexakis (mercaptoacetate), diventaerythritol bentaquinu (mercaptoacetate), dipentaerythritol tetrakis (mercaptoacetate).
Diventaerythritol tris (mercaptoacetate), diventaerythritol bis(mercaptoacetate), diventaerythritol monomercabutoacetate, diventaerythritol hexakis (β-merkabutopropionate), diventaerythritol Bentakis (l-mercaptopropionate), diventaerythritol tetraki7 (β-mercaptopropionate)
．． Diventaerythritol tris(β-meμ-kabutopropionate), diventaerythritol bis(β-mercaptopropionate), diventaerythritol monoβ-mercaptopropionate. 3-ethylthio-2-
Hydroxypropylbutane, 3-butylthio2
-Hydroxypropylmerbutane, 3-octylthio-2-hydroxypropylmercade! "*3 ysilthio-2-hydroxyglopinolemer butane.3-
dodecymuthio-2-hydroxyglopyrubutane,
Examples thereof include 3-tethodecylthio-2-hydroxypropylbutane, 3-hexadecylthio-2-hydroxypropylbutane, and 3-octadecylthio-2-hydroxyglopylbutane.

The compositions of the invention may include plasticizers, such as phthalate esters,
Adipic acid entel, sebacic acid entel, azelaic acid ester/L/, }limellitic acid ester, biromellitic acid entel, citric acid ester. Plasticizers commonly used for vinyl chloride resins, such as phosphoric acid esters and polyester plasticizers, can be blended.

Also, other thermoplastic resins, rubbers, and fillers as necessary. Pigments, processing aids, etc. can be blended. Other thermoplastic resins include ethylene/vinyl acetate copolymer, chlorinated polyethylene, ABS resin, AS resin, urethane resin, acrylic resin, ethylene/hypogen monoxide/vinyl acetate copolymer, etc. is NBR. Examples include CR.

Additionally, the compositions of the present invention may optionally contain an organotin stabilizer. Other metal soap stabilizers, organophosphorus compounds. Organic nitrogen stabilizers, zeolites, hydrotalcites, polyhydric alcohols, diketone compounds, antioxidants, ultraviolet absorbers, lubricants, antistatic agents, etc. can be added.

The resin composition of the present invention is mixed using a suitable mixing device such as a Henschel mixer, and then extrusion molded or injection molded. The article can be sterilized by irradiating the resulting molded article with gamma rays at an irradiation dose of 0.5 to 7 megarads.

[Function] Due to the action of the thioalcohol compound, the resin composition of the present invention greatly reduces the yellowing and deterioration of the resin caused by γ-ray irradiation, and does not impair the safety and health of medical equipment. It can be used for applications such as packaging materials.

〔Example〕

Next, the present invention will be explained with reference to examples, where parts in the examples indicate parts by weight.

Example 1 PVC=/L/Resin (Geon 103 EP -
8. Nippon Zeon Co., Ltd.) 100 parts K, epoxidized soybean oil 1
Department. Add 0.5 part of calcium stearate, 0.5 part of zinc stearate, and 1 part of the 1,000-alcohol compound shown in Table 1 below, and place on a mixing roll at 170°C with a thickness of 0.5.
Create a sheet of mm, overlap two sheets, and make 17 mm.
A press plate was produced at 5°C. Cobalt 60 on each press plate
γ-rays were irradiated using a radiation source with a dose of 3 megarads. The hue after γ-ray irradiation was measured with a fully automatic colorimeter Color Ace TC-PI (manufactured by Tokyo Denshoku Co., Ltd.).
The change in hue was expressed in lE.

The results are shown in Table 1.

Table 1 Example 2 To 100 parts of vinyl chloride resin (Geon 103 EP-8D, manufactured by Zeon Corporation), 3 parts of epoxidized linseed oil,
Example 1: 1 part of calcium laurate, 1 part of zinc laurate, and 2 parts of the thioalcohol compound shown in Table 2 below were added.
A press plate was manufactured in the same manner as above, and 5 megarads of γ-rays were irradiated using a Kobal}60 radiation source, and ΔE was measured.

The results are shown in Table 2.

Table 2 [Effects of the Invention] As is clear from the ΔE after γ-ray irradiation in Examples 1 and 2 above, in the present invention, if a thioalcohol compound is added to the pinychloride/L-based resin, γ-ray irradiation can be reduced. The discoloration and coloring caused by this resin can be extremely reduced, and sterilization has become easier without impairing the quality of the resin.

Claims (1)

[Claims] A radiation-resistant resin composition comprising a vinyl chloride resin mixed with an epoxidized vegetable oil, an organic carboxylic acid calcium salt, an organic carboxylic acid zinc salt, and a thioalcohol compound.