JP3330781B2 - Polycarbonate resin composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polycarbonate resin composition containing a compound having a cyclic acetal group, which has a small change in color tone and deterioration of physical properties due to ionizing radiation irradiated for sterilization. , Medical devices or components of medical devices.

[0002]

2. Description of the Related Art Polycarbonate resins have excellent mechanical strength, impact strength, heat resistance, transparency, and high safety, and are widely used for molding medical products. Medical molded articles made of these polycarbonate resin compositions are usually completely sterilized when used. Specifically, high-pressure steam sterilization, ethylene oxide gas (EO
G) Sterilization method, sterilization method by irradiation with ionizing radiation such as gamma ray or electron beam, and the like. However, among these, the high-pressure steam sterilization method has problems such as high energy cost and a necessity of a drying step after the sterilization treatment. Further, EOG sterilization has various problems such as the toxicity of EOG itself and environmental problems associated with disposal.

Therefore, recently, relatively inexpensive, low-temperature,
Ionizing radiation (typically gamma radiation) irradiation sterilization, which can be processed dry, has become popular. However, the polycarbonate resin, when irradiated with ionizing radiation for sterilization, usually turns yellow due to the deterioration of the resin, and as a result of such yellowing, the disadvantage that the product value is impaired, especially in medical applications. have.

As a method of solving such a drawback, for example, Japanese Patent Publication No. 2-17582 discloses a method of blending a boron compound, and Japanese Patent Publication No. 4-77025 discloses a method of blending a polyether polyol or its alkyl ether. Japanese Patent Publication No. Hei 6-13639 describes a method of blending itaconic acid, benzaldehyde dimethyl acetal, p-phthalaldehyde, etc., but the yellowing inhibiting effect is insufficient or insufficient. Increasing the amount of addition to obtain the effect has a problem that other physical properties are adversely affected.

Japanese Patent Publication No. 6-22586 describes a method of blending a halogen-containing polycarbonate resin, and Japanese Patent Application Laid-Open No. 5-179127 describes a method of blending a nuclear brominated phthalic acid derivative. Since the composition contains halogen, metal corrosion is apt to occur, and it has been necessary to use a metal of a special material in a molding machine or the like.

As a method of using a sulfur compound, a method of blending thioalcohols in JP-A-1-229052 and a method of blending thioethers in JP-A-2-115260 are disclosed in JP-A-2-115260. 490
No. 58, JP-A-4-36343 and JP-A-6-166
Japanese Patent Application Laid-Open No. 807 discloses a method of compounding a compound having a mercapto group, and Japanese Patent Application Laid-Open No. 6-93192 describes a method of compounding a compound having a sulfide group. In addition, there is a problem that an unpleasant odor is generated during use and the environment during molding is deteriorated.

[0007]

The problem to be solved by the present invention is to obtain a polycarbonate resin composition which has a very small yellowing at the time of ionizing radiation irradiation sterilization and which has sufficient mechanical properties and the like. It is.

[0008]

Means for Solving the Problems The present inventors have prepared (B) a compound (B) having a cyclic acetal group represented by the following general formula (I) or (II) per 100 parts by weight of a polycarbonate resin. The present invention was completed by finding a polycarbonate resin composition characterized by blending 0.01 to 5 parts by weight.

[0009]

Embedded image

Wherein R ¹ is a C1-15 alkylene group, alkenylene group or arylene group, and R ² is
It may be different from each other the same, H, an alkyl group of C1 -4, _-CH 2 OH group, _-CO 2 CH ₃ group or a phenyl group, X is, -CH ₂ - group, -CHR ³ -
_{Group, -O (CH 2 CH 2 O} ) q- group (q = 1~5), -
O-, -NH- or -PH-, wherein R ³ is
R ⁴ is H, a C 1-30 alkyl group, a cycloalkyl group, an alkenyl group, an aryl group, an arylalkyl group, an arylalkenyl group, an alkoxyalkyl group, an acyl group, a halogen group, It is a halogenated alkyl group, an amino group or an aminated alkyl group. n and m are each independently an integer of 1 to 10, and j and k are each independently 0 or 1. )

[0011] The polycarbonate resin used in the present invention is an aromatic dihydroxy compound or a small amount of a polyhydroxy compound, which may be obtained by reacting with a phosgene or a carbonic acid diester. It is a polycarbonate polymer or copolymer. In the present invention, the molecular weight of the polycarbonate resin is 10,000 to 1000 as a viscosity average molecular weight calculated from the viscosity of a methylene chloride solution at 25 ° C.
00, preferably in the range of 15,000 to 50,000.

Specific examples of the aromatic dihydroxy compound include 2,2-bis (4-hydroxyphenyl) propane (= bisphenol A) and 2,2-bis (3,5-dibromo-4-hydroxyphenyl) propane ( = Tetrabromobisphenol A), bis (4-hydroxyphenyl) methane, 1,1-bis (4-hydroxyphenyl)
Ethane, 2,2-bis (4-hydroxyphenyl) butane, 2,2-bis (4-hydroxyphenyl) octane, 2,2-bis (4-hydroxy-3-methylphenyl) propane, 1,1-bis (3-t-butyl-4-hydroxyphenyl) propane, 2,2-bis (4-hydroxy-3,5-dimethylphenyl) propane, 2,2
-Bis (3-bromo-4-hydroxyphenyl) propane, 2,2-bis (3,5-dichloro-4-hydroxyphenyl) propane, 2,2-bis (3-phenyl-4
-Hydroxyphenyl) propane, 2,2-bis (3-
Cyclohexyl-4-hydroxyphenyl) propane,
Bis (hydroxyaryl) alkanes exemplified by 1,1-bis (4-hydroxyphenyl-1-phenylethane, bis (4-hydroxyphenyl) diphenylmethane and the like; 1,1-bis (4-hydroxyphenyl) cyclopentane , 1,1-bis (4-hydroxyphenyl) cyclohexane and the like; bis (hydroxyaryl) cycloalkanes; 4,4′-dihydroxydiphenyl ether, 4,4′-dihydroxy-3,3′-dimethyldiphenyl ether and the like 4,4′-dihydroxydiphenyl sulfide, 4,4′-dihydroxy-3,3′-
Dihydroxydiaryl sulfides exemplified by dimethyldiphenyl sulfide and the like; 4,4′-dihydroxydiphenyl sulfoxide, 4,4′-dihydroxy-
Dihydroxydiarylsulfoxides exemplified by 3,3′-dimethyldiphenylsulfoxide and the like; 4,4 ′
Dihydroxydiarylsulfones exemplified by -dihydroxydiphenylsulfone, 4,4'-dihydroxy-3,3'-dimethyldiphenylsulfone; hydroquinone, resorcinol, 4,4'-dihydroxydiphenyl and the like. These aromatic dihydroxy compounds may be used alone or in combination of two or more. Among them, 2,2-bis (4-hydroxyphenyl) propane is particularly preferably used.

In order to obtain a branched aromatic polycarbonate resin, phloroglysin, 2,6-dimethyl-
2,4,6-tri (4-hydroxyphenyl) -3-heptene, 4,6-dimethyl-2,4,6-tri (4-hydroxyphenyl) -2-heptene, 1,3,5-tri ( 2-hydroxyphenyl) benzol, 1,1,1-
Tri (4-hydroxyphenyl) ethane, 2,6-bis (2-hydroxy-5-methylbenzyl) -4-methylphenol, α, α ′, α ″ -tri (4-hydroxyphenyl) -1,3,3 Polyhydroxy compounds exemplified by 5-triisopropylbenzene and the like, and 3,3-bis (4-hydroxyaryl) oxindole (= isatin bisphenol), 5-chlorisatin bisphenol, 5,7-dichlorisatin bisphenol , 5-
Bromoisatin bisphenol or the like is used.

When polycarbonate is produced by the phosgene method, a terminal stopper or a molecular weight regulator may be used. As the terminal terminator or the molecular weight regulator, a compound having a monovalent phenolic hydroxyl group or a compound having an aromatic carboxylic acid group can be used. Specifically, phenol, pt-butylphenol, tribromophenol, long-chain alkylphenol, aliphatic carboxylic acid chloride, aliphatic carboxylic acid, hydroxybenzoic acid alkyl ester, alkyl ether phenol,
Examples thereof include benzoic acid and alkylbenzoic acid.

In the present invention, these polycarbonate resins are used alone or as a mixture of two or more.

The compound having a cyclic acetal group used in the present invention is a compound having a cyclic acetal group represented by the following general formula (I) or (II).

[0017]

Embedded image

(Wherein R ¹ is a C1-15 alkylene group, alkenylene group or arylene group, and R ² is
It may be different from each other the same, H, an alkyl group of C1 -4, _-CH 2 OH group, _-CO 2 CH ₃ group or a phenyl group, X is, -CH ₂ - group, -CHR ³ -
_{Group, -O (CH 2 CH 2 O} ) q- group (q = 1~5), -
O-, -NH- or -PH-, wherein R ³ is
R ⁴ is H, a C 1-30 alkyl group, a cycloalkyl group, an alkenyl group, an aryl group, an arylalkyl group, an arylalkenyl group, an alkoxyalkyl group, an acyl group, a halogen group, It is a halogenated alkyl group, an amino group or an aminated alkyl group. n and m are each independently an integer of 1 to 10, and j and k are each independently 0 or 1. The compounds having a cyclic acetal group may be used individually or as a mixture of two or more.

Specifically, as the compound of the general formula (I), 2,2'-ethylenebis-1,3-dioxolan,
2,2′-trimethylenebis-1,3-dioxolan,
2,2′-phenylenebis-1,3-dioxolan. As the compound of the general formula (II), 2-methyl-1,3-dioxolan, 2-n-hexyl-1,3-
Dioxolan, 2-methoxy-1,3-dioxolan,
2-chloromethyl-1,3-dioxolan, 2-bromomethyl-1,3-dioxolan, 2- (2-bromoethyl) -1,3-dioxolan, 2-aminomethyl-1,
3-dioxolan, 2- (2-aminoethyl) -1,3
-Dioxolan, 2-benzyl-1,3-dioxolan, 2- {2- (2-methoxyethoxy) ethoxy}-
1,3-dioxolan.

In the present invention, the compound having a cyclic acetal group is used in an amount of 0.01 to 2.0 parts by weight of the compound having a cyclic acetal group per 100 parts by weight of the polycarbonate resin.
5 parts by weight, preferably 0.05 to 3 parts by weight. If the amount is less than 0.01 part by weight, the effect of improving the degree of yellowing by irradiation with the intended ionizing radiation is insufficient, and if it exceeds 5 parts by weight, the mechanical properties, heat resistance and the like are undesirably reduced. .

In the present invention, the compound having a cyclic acetal group may be compounded into the polycarbonate resin by any of various methods well-known to those skilled in the art at any stage immediately before molding the final molded article. it can. For example, there is a method of mixing with a tumbler, a Henschel mixer, or the like, a method of quantitatively supplying the mixture to an extruder hopper by a feeder and mixing.

The composition of the present invention may further contain other additives for imparting desired properties depending on the purpose. Other additives include, for example, a flame retardant such as a halogen compound, a phosphorus compound, a metal sulfonic acid salt, a flame retardant auxiliary such as an antimony compound and a zirconium compound, and prevention of dripping during ignition of polytetrafluoroethylene and a silicon compound. Agent,
Impact modifiers such as elastomers, antioxidants, heat stabilizers, ultraviolet absorbers, antistatic agents, plasticizers, release agents, lubricants, compatibilizers, foaming agents, glass fibers, glass beads, glass flakes, carbon Reinforcing agents such as fibers, fibrous magnesium, potassium titanate whiskers, ceramic whiskers, mica, and talc, fillers, dyes and pigments can be used. One or more of these additives can be added.

The composition of the present invention can be formed into a desired molded product according to a conventional molding method such as injection molding or blow molding. Medical molded articles for which it is desired to apply the ionizing radiation-resistant polycarbonate resin composition of the present invention include, specifically, artificial dialysers, artificial lungs, inhalation devices for anesthesia, intravenous connectors and accessories. Blood centrifuge bowls, surgical tools, operating room tools, tubing to supply oxygen to blood, tubing fittings, heart probes and syringes,
Examples include surgical tools, operating room instruments, containers for holding intravenous injections, and the like.

Hereinafter, the present invention will be described in detail with reference to Examples and Comparative Examples, but the present invention is not limited thereto.

【Example】

Examples 1 to 5 and Comparative Example 1 Polycarbonate resin (Iupilon S-2000, manufactured by Mitsubishi Gas Chemical Co., Ltd .; poly-4,4'-isopropylidene diphenyl carbonate having a viscosity average molecular weight of 25,000) 100 Parts by weight and a compound having a cyclic acetal group shown in Table 1 were mixed in a tumbler at a ratio shown in Table 1 and extruded at a barrel temperature of 270 ° C. using a 40 mmφ uniaxial vented extruder. A pellet was obtained.

The pellets are placed in a hot air drier at 120
After drying at 5 ° C. for 5 hours or more, injection molding was performed at a resin temperature of 270 ° C. and a mold temperature of 80 ° C. to prepare a test piece having a thickness of 50 mm × 3 mm. This test piece was irradiated with 25 kg of cobalt 60 γ-ray (kGy), and the yellowness (YI) before and after irradiation was measured with a color difference meter (trade name: SM-3-CH, manufactured by Suga Test Instruments Co., Ltd.) in accordance with JIS K7103. The difference in yellowness and yellowing degree (ΔYI) were determined. Table 1 shows the results.

[0027]

[Table 1]

[0028]

Industrial Applicability The composition of the present invention has a small change in color tone due to ionizing radiation irradiated for sterilization, and can maintain a good appearance even by ionizing radiation irradiation sterilization. It is useful for applications.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-2-132147 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) C08L 69/00

Claims (5)

(57) [Claims] 1. A compound having a cyclic acetal group represented by the following formula (I) or (II): 0.01 to 5 parts by weight is blended with (A) 100 parts by weight of a polycarbonate resin. A polycarbonate resin composition, characterized in that: Embedded image (Wherein, R ¹ is a C1-15 alkylene group, alkenylene group or arylene group, and R ² may be the same or different, H, an alkyl group of C1-4,
—CH ₂ OH group, —CO ₂ CH ₃ group or phenyl group, and X represents —CH ₂ — group, —CHR ³ — group, —O (CH
₂ CH ₂ O) q- group (q = 1~5), - O- groups, -NH
Or a —PH— group, R ³ is a C1-4 alkyl group, and R ⁴ is H, a C1-30 alkyl group, a cycloalkyl group, an alkenyl group, an aryl group, an arylalkyl group, Arylalkenyl group, alkoxyalkyl group, acyl group, halogen group, halogenated alkyl group,
It is an amino group or an aminated alkyl group. n and m are
Independently, are integers from 1 to 10, and j and k are independently
It is 0 or 1. ) 2. The composition according to claim 1, wherein the compound having a cyclic acetal group is a compound represented by the general formula (I) wherein n = m = 2. 3. The compound having a cyclic acetal group is a compound represented by the general formula (II) wherein n = 2.
A composition as described. 4. The composition according to claim 3, wherein X = —CH ₂ —. 5. The composition according to claim 3, wherein X = —O—.