JP2023051362A - Resin composition for container - Google Patents

Abstract

To provide a resin composition for a container which enables molding of a container that is excellent in moldability, transparency and steam-resistant sterilization property.SOLUTION: A resin composition for a container contains a cyclic olefinic resin, and 0.01 pts.mass or more and 10 pts.mass or less of a chain-like hydrocarbon-based processing aid with respect to 100 pts.mass of the cyclic olefinic resin. A glass transition temperature (Tg) of the cyclic olefinic resin is set at 125°C or higher and 200°C or lower, and a number average molecular weight (Mn) of the chain-like hydrocarbon-based processing aid is set at 100 or more and 5,000 or less.SELECTED DRAWING: None

Description

TECHNICAL FIELD The present invention relates to a resin composition, and more particularly to a resin composition for containers used as a material for molding containers.

Conventionally, resin compositions have been used as materials for various molded articles for automobiles, electronic parts, optical parts, household appliance parts, and the like. As such a resin composition, for example, Patent Document 1 discloses a hydrogenated crystalline cyclic olefin ring-opening polymer having a repeating unit derived from a polycyclic norbornene-based monomer, and describes a resin composition containing a predetermined amount of wax and a nucleating agent. According to this resin composition, even if injection molding is performed at a relatively low mold temperature, the crystallization proceeds sufficiently, and a molded article that is less likely to be deformed by the influence of heat can be obtained. Moreover, according to this resin composition, it is possible to obtain an LED light reflector that maintains excellent light reflectance for a long period of time without lowering even under high-temperature conditions, with good moldability.

WO2012/033076

However, the resin composition described in Patent Document 1 has insufficient moldability for use as a material for molding a container having a complicated shape. Further, there is room for improvement in terms of improving the transparency and steam sterilization resistance of the container molded using the resin composition.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a resin composition for a container which is excellent in moldability and capable of being molded into a container having excellent transparency and steam sterilization resistance.

The inventor of the present invention made earnest studies to solve the above problems. Then, the present inventors have developed a resin composition containing a cyclic olefin resin and a predetermined amount of a chain hydrocarbon-based processing aid for the cyclic olefin resin, wherein the glass transition of the cyclic olefin resin is A resin composition in which the temperature (Tg) is within a predetermined range and the number average molecular weight (Mn) of the chain hydrocarbon-based processing aid is within a predetermined range is used to mold a container having a complicated shape. It was found that excellent moldability can be exhibited even when used as a material for. Further, the inventors have found that a container having excellent transparency and resistance to steam sterilization can be formed by using the resin composition, and completed the present invention.

That is, the object of the present invention is to advantageously solve the above problems, and the resin composition for containers of the present invention comprises a cyclic olefin-based resin and A resin composition for containers containing 0.01 parts by mass or more and 10 parts by mass or less of a chain hydrocarbon-based processing aid, wherein the cyclic olefin resin has a glass transition temperature (Tg) of 125° C. or more and 200° C. or less. and the number average molecular weight (Mn) of the chain hydrocarbon-based processing aid is 100 or more and 5,000 or less. Thus, a resin composition containing a cyclic olefin-based resin and a predetermined amount of a chain hydrocarbon-based processing aid for the cyclic olefin-based resin, wherein the glass transition temperature (Tg) of the cyclic olefin-based resin is A resin composition in which the number average molecular weight (Mn) of the chain hydrocarbon-based processing aid is within the predetermined range is within the predetermined range, and is excellent in moldability, particularly when molding a container having a complicated shape. Even when used as a material, it can exhibit excellent moldability. By using this resin composition, a container having excellent transparency and steam sterilization resistance can be molded.
In addition, in the present invention, the "glass transition temperature (Tg)" of the cyclic olefin resin can be measured by the method described in the Examples of the present specification.
In the present invention, the "number average molecular weight (Mn)" of the chain hydrocarbon-based processing aid refers to a standard polystyrene conversion value obtained by gel permeation chromatography (GPC) using tetrahydrofuran as a developing solvent.

Here, the resin composition for a container of the present invention further contains 0.01 parts by mass or more and 0.5 parts by mass or less of a hydrogenated styrene-conjugated diene block copolymer with respect to 100 parts by mass of the cyclic olefin resin. It is preferably contained in proportion. Furthermore, when the hydrogenated styrene-conjugated diene block copolymer is contained in the above-mentioned predetermined ratio, a container having improved steam sterilization resistance and moisture resistance can be molded.

In the container resin composition of the present invention, the chain hydrocarbon-based processing aid preferably comprises a chain saturated hydrocarbon. By using a chain hydrocarbon-based processing aid composed of a chain saturated hydrocarbon, it is possible to mold a container with further improved transparency.

ADVANTAGE OF THE INVENTION According to this invention, it is excellent in moldability, and can provide the resin composition for containers which can mold a container excellent in transparency and steam sterilization resistance.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail. Here, the resin composition for containers of the present invention can be used as a material for molding various containers. Among others, the container resin composition of the present invention can be suitably used as a material for molding a container having a complicated shape.

(Resin composition for containers)
The resin composition for containers of the present invention comprises a cyclic olefin resin and a chain hydrocarbon processing aid, and optionally components other than the cyclic olefin resin and the chain hydrocarbon processing aid (hereinafter referred to as (referred to as "other ingredients"). The container resin composition of the present invention contains a chain hydrocarbon processing aid in a proportion of 0.01 parts by mass or more and 10 parts by mass or less with respect to 100 parts by mass of the cyclic olefin resin. The glass transition temperature (Tg) is 125° C. or higher and 200° C. or lower, and the number average molecular weight (Mn) of the chain hydrocarbon-based processing aid is 100 or higher and 5,000 or lower.

Since the resin composition for containers of the present invention contains the cyclic olefin resin having the predetermined properties and the chain hydrocarbon-based processing aid in a predetermined ratio, it has excellent moldability. Even when used as a material for molding a container having a complicated shape, it can exhibit excellent moldability. By using the resin composition for containers of the present invention, containers having excellent transparency and steam sterilization resistance can be molded.

<Cyclic olefin resin>
Since the resin composition for a container of the present invention contains a cyclic olefin resin, it can be molded into a container having excellent transparency and moisture resistance.
Examples of cyclic olefin resins include ring-opening polymers of cyclic olefins, hydrogenated ring-opening polymers of cyclic olefins, and copolymers of cyclic olefins and chain olefins.
These cyclic olefin resins can be used singly or in combination of two or more.

<< Ring-opening polymer of cyclic olefin >>
A ring-opening polymer of a cyclic olefin is a polymer obtained by ring-opening polymerization of one or more types of cyclic olefins.

Specific examples of cyclic olefins include monocyclic cyclic olefins such as cyclopentene, cyclohexene, cyclooctene, cyclopentadiene, and 1,3-cyclohexadiene;

bicyclo[2.2.1]hept-2-ene (common name: norbornene), 5-methyl-bicyclo[2.2.1]hept-2-ene, 5,5-dimethyl-bicyclo[2.2. 1]hept-2-ene, 5-ethyl-bicyclo[2.2.1]hept-2-ene, 5-butyl-bicyclo[2.2.1]hept-2-ene, 5-ethylidene-bicyclo[ 2.2.1]hept-2-ene, 5-hexyl-bicyclo[2.2.1]hept-2-ene, 5-octyl-bicyclo[2.2.1]hept-2-ene, 5- Octadecyl-bicyclo[2.2.1]hept-2-ene, 5-methylidene-bicyclo[2.2.1]hept-2-ene, 5-vinyl-bicyclo[2.2.1]hept-2- bicyclic cyclic olefins such as ene, 5-propenyl-bicyclo[2.2.1]hept-2-ene;

tricyclo[5.2.1.0 ^2,6 ]deca-3,8-diene (common name: dicyclopentadiene), tricyclo[4.3.0.12,5]deca-3,7-diene, tricyclo [5.2.1.0 ^2,6 ]deca-3-ene, tricyclo[6.2.1.0 ^2,7 ]undeca-3,9-diene, tricyclo[6.2.1.0 ^{2, 7} ]undec-4,9-diene, tricyclo[6.2.1.0 ^2,7 ]undec-9-ene, 5-cyclopentyl-bicyclo[2.2.1]hept-2-ene, 5-cyclohexyl -bicyclo[2.2.1]hept-2-ene, 5-cyclohexenylbicyclo[2.2.1]hept-2-ene, 5-phenyl-bicyclo[2.2.1]hept-2-ene tricyclic cyclic olefins such as

Tetracyclo[6.2.1.1 ^3,6 . 0 ^2,7 ]dodeca-4-ene, tetracyclo[4.4.0.12,5.17,10]dodeca-3-ene, 9-methyltetracyclo[6.2.1.1 ^3,6 . 0 ^2,7 ]dodeca-4-ene, 9-ethyltetracyclo[6.2.1.1 ^3,6 . 0 ^2,7 ]dodeca-4-ene, 8-ethyltetracyclo[4.4.0.12,5.17,10]dodeca-3-ene, 9-methylidenetetracyclo[6.2.1. 1 ^{3, 6} . 0 ^2,7 ]dodeca-4-ene, 9-ethylidenetetracyclo[6.2.1.1 ^3,6 . 0 ^2,7 ]dodeca-4-ene, 9-vinyltetracyclo[6.2.1.1 ^3,6 . 0 ^2,7 ]dodeca-4-ene, 9-propenyl-tetracyclo[6.2.1.1 ^3,6 . 0 ^2,7 ]dodeca-4-ene, tetracyclo[9.2.1.0 ^2,10 . 0 ^3,8 ]tetradeca-3,5,7,12-tetraene (also referred to as 1,4-methano-1,4,4a,9a-tetrahydrofluorene), tetracyclo[7.4.0.02,7. 110,13]tetradeca-2,4,6,11-tetraene, tetracyclo[10.2.1.0 ^2,11 . 0 ^4,9 ]4-ring cyclic olefins such as pentadeca-4,6,8,13-tetraene (also referred to as 1,4-methano-1,4,4a,9,9a,10-hexahydroanthracene);

9-Cyclopentyl-tetracyclo[6.2.1.1 ^3,6 . 0 ^2,7 ]dodeca-4-ene, 9-cyclohexyl-tetracyclo[6.2.1.1 ^3,6 . 0 ^2,7 ]dodeca-4-ene, 9-cyclohexenyl-tetracyclo[6.2.1.1 ^3,6 . 0 ^2,7 ]dodeca-4-ene, pentacyclo[6.6.1.1 ^3,6 . 0 ^{2, 7} . 0 ^9,14 ]-4-hexadecene, pentacyclo[6.5.1.1 ^3,6 . 0 ^{2, 7} . 0 ^9,13 ]-4-pentadecene, pentacyclo[7.4.0.0 ^2,7 . 1 ^{3, 6} . 1 ^10,13 ]-4-pentadecene, 9-phenyl-cyclopentyl-tetracyclo[6.2.1.1 ^3,6 . 0 ^2,7 ]dodeca-4-ene, heptacyclo[8.7.0.1 ^2,9 . 1 ^{4, 7} . 1 ^{11, 17} . 0 ^{3, 8} . 0 ^12,16 ]-5-eicosene, heptacyclo[8.7.0.1 ^2,9 . 0 ^{3, 8} . 1 ^{4, 7} . 0 ^{12, 17} . 1 ^13,16 ]-14-eicosene and other cyclic olefins having five or more rings.
These cyclic olefins can be used alone or in combination of two or more.

The method for preparing the ring-opening polymer of cyclic olefin is not particularly limited, and a known method for ring-opening polymerization of the cyclic olefin described above, such as metathesis polymerization, can be used.

<<Hydrogenated product of ring-opening polymer of cyclic olefin>>
The hydrogenated product of the ring-opened cyclic olefin polymer is obtained by hydrogenating the above-mentioned ring-opened cyclic olefin polymer.
The method of hydrogenating the ring-opening polymer of the cyclic olefin is not particularly limited, and a known method can be used. and a method of hydrogenating the carbon-carbon double bond in the ring-opening polymer by adding a known hydrogenation catalyst containing a transition metal.
Moreover, the hydrogenation rate is preferably 90% or more, more preferably 95% or more, and even more preferably 99% or more.
The hydrogenation rate can be measured by the method described in the examples of this specification.

<<Copolymer of Cyclic Olefin and Chain Olefin>>
A copolymer of a cyclic olefin and a chain olefin is usually a polymer obtained by addition copolymerization of a cyclic olefin and a chain olefin.

As the cyclic olefin, the same cyclic olefins as those used in the preparation of the ring-opening polymer of the cyclic olefin described above can be used.

Specific examples of chain olefins are not particularly limited as long as they are copolymerizable with the cyclic olefins described above. 2 to 20 linear or branched olefins may be mentioned.

A method for preparing a copolymer of a cyclic olefin and a chain olefin is not particularly limited, and a known method for copolymerizing a cyclic olefin and a chain olefin described above can be used.

-Glass transition temperature (Tg)-
In the container resin composition of the present invention, the glass transition temperature (Tg) of the cyclic olefin-based resin described above is 125° C. or higher, preferably 130° C. or higher, more preferably 135° C. or higher. It is 200° C. or lower, preferably 190° C. or lower, and more preferably 180° C. or lower. When the glass transition temperature of the cyclic olefin resin is 125°C or higher, the resin composition for containers has excellent moldability. Further, when the glass transition temperature of the cyclic olefin resin is 200° C. or less, a container can be molded in which deformation at high temperatures is suppressed.

<Chain hydrocarbon-based processing aid>
The chain hydrocarbon-based processing aid contained in the container resin composition of the present invention is a component that improves the moldability of the cyclic olefin-based resin. As the chain hydrocarbon-based processing aid, for example, a chain hydrocarbon-based processing aid composed of a chain saturated hydrocarbon or a chain hydrocarbon-based processing aid composed of a chain unsaturated hydrocarbon can be used. can.

Examples of chain hydrocarbon-based processing aids composed of chain saturated hydrocarbons include polyethylene, polypropylene, paraffin, and hydrogenated polybutene. Examples of chain hydrocarbon-based processing aids composed of chain unsaturated hydrocarbons include polybutene. Among these, from the viewpoint of further improving the transparency of the container, the chain hydrocarbon-based processing aid is preferably a chain hydrocarbon-based processing aid composed of chain saturated hydrocarbons, polyethylene, hydrogenated Polybutene is more preferred.
These chain hydrocarbon-based processing aids can be used singly or in combination of two or more.

In addition, the number average molecular weight (Mn) of the chain hydrocarbon-based processing aid is 100 or more, preferably 200 or more, more preferably 500 or more, and 5,000 or less. It is preferably 000 or less, more preferably 2,000 or less. If the chain hydrocarbon-based processing aid has a number average molecular weight of 100 or more, a container with excellent transparency can be formed. Further, when the number average molecular weight of the chain hydrocarbon-based processing aid is 5,000 or less, mold contamination can be prevented when molding a container using the container resin composition of the present invention. .

The ratio of the chain hydrocarbon-based processing aid contained in the resin composition for containers of the present invention is 0.01 parts by mass or more and 0.05 parts by mass with respect to 100 parts by mass of the cyclic olefin resin. It is preferably 1 part or more, more preferably 0.1 part by mass or more, 10 parts by mass or less, preferably 5 parts by mass or less, and more preferably 1 part by mass or less. If the content of the chain hydrocarbon-based processing aid is at least the above lower limit, the transparency of the container can be further enhanced. Further, when the content of the chain hydrocarbon-based processing aid is equal to or less than the above upper limit, the moldability of the resin composition for containers can be further improved.

<Other ingredients>
The resin composition for containers of the present invention is not particularly limited as long as it does not impair the effects of the present invention, and can optionally contain other components. Other components include, for example, various additives. Additives are not particularly limited, and examples thereof include antioxidants, ultraviolet absorbers, light stabilizers, near-infrared absorbers, lubricants, and release agents. Furthermore, the resin composition for containers of the present invention may contain, as other components, resin components other than the cyclic olefin resin (hereinafter referred to as "other resin components").

The resin composition for containers of the present invention preferably contains a hydrogenated styrene-conjugated diene block copolymer as another resin component. If the styrene-conjugated diene block copolymer hydride is contained, the moisture resistance of the container can be improved.

<Styrene-conjugated diene block copolymer hydride>
Here, the hydrogenated styrene-conjugated diene block copolymer includes a styrene block mainly composed of repeating units derived from a styrene monomer and a diene block mainly composed of repeating units derived from a conjugated diene monomer. It is a hydride of a styrene block-conjugated diene block copolymer having

Specific examples of styrene-based monomers that give styrene blocks include styrene, α-methylstyrene, 2-methylstyrene, 3-methylstyrene, 4-methylstyrene, 2,4-diisopropylstyrene, 2,4- Examples include dimethylstyrene, 4-t-butylstyrene, 5-t-butyl-2-methylstyrene, 4-monochlorostyrene, dichlorostyrene, 4-monofluorostyrene, and 4-phenylstyrene, which are polar in terms of hygroscopicity. Those containing no groups are preferred, with styrene being particularly preferred.
In addition to repeating units derived from styrene-based monomers, the styrene block contains other monomer units such as repeating units derived from other vinyl compounds and repeating units derived from chain conjugated diene compounds. may The content ratio of these other monomer units is usually 10% by mass or less, preferably 5% by mass or less, relative to the total styrene blocks.

Specific examples of the conjugated diene monomer that provides the diene block include linear conjugated diene compounds such as 1,3-butadiene, isoprene, 2,3-dimethyl-1,3-butadiene, and 1,3-pentadiene. 1,3-butadiene and isoprene are particularly preferred from the viewpoint of hygroscopicity.

The diene block may contain, in addition to repeating units derived from a conjugated diene monomer, other monomeric units such as repeating units derived from styrene monomers and repeating units derived from other vinyl compounds. . From the viewpoint of further suppressing the occurrence of mold contamination when molding a container using the container composition of the present invention, the content ratio of these other monomer units relative to the total diene block is It is usually 10% by mass or less, preferably 5% by mass or less.

Specific examples of hydrogenated styrene-conjugated diene block copolymers include styrene-ethylene/butene block copolymer (SEB), styrene-ethylene/butylene-styrene block copolymer (SEBS), styrene-ethylene/propylene- Styrene block copolymer (SEPS) and the like are included.

The weight average molecular weight (Mw) of the hydrogenated styrene-conjugated diene block copolymer is preferably 30,000 or more, more preferably 40,000 or more, and further preferably 50,000 or more. It is preferably 200,000 or less, more preferably 150,000 or less, even more preferably 100,000 or less. If the weight average molecular weight of the hydrogenated styrene-conjugated diene block copolymer is within the above range, the mechanical strength and heat resistance of the container molded using the container resin composition are improved.

The molecular weight distribution (Mw/Mn) of the hydrogenated styrene-conjugated diene block copolymer is preferably 3 or less, more preferably 2 or less, and even more preferably 1.5 or less. If the weight average molecular weight of the hydrogenated styrene-conjugated diene block copolymer is within the above range, the mechanical strength and heat resistance of the container molded using the container resin composition are further improved.
The weight average molecular weight and molecular weight distribution of the hydrogenated styrene-conjugated diene block copolymer can be determined as polystyrene equivalent values by gel permeation chromatography using tetrahydrofuran as a solvent.

As the hydrogenated styrene-conjugated diene block copolymer, for example, commercially available products can be used. In addition, the hydrogenated styrene-conjugated diene block copolymer can be obtained by obtaining a styrene-conjugated diene block copolymer according to a known method, and then obtaining a conjugated diene block main chain and It may be obtained by hydrogenating the carbon-carbon unsaturated bond of the side chain. At that time, the hydrogenation rate of the styrene-conjugated diene block copolymer is 90% or more, preferably 97% or more, more preferably 99% or more. The higher the hydrogenation rate, the easier it is to form a container with excellent transparency and steam sterilization resistance. The hydrogenation rate of the hydrogenated styrene-conjugated diene block copolymer can be obtained by measurement by ¹ H-NMR.
Here, the method for hydrogenating the unsaturated bond, the reaction form, and the like are not particularly limited, and the hydrogenation may be carried out according to known methods.

The ratio of the hydrogenated styrene-conjugated diene block copolymer that can be contained in the resin composition for containers of the present invention is 0.01 part by mass or more with respect to 100 parts by mass of the cyclic olefin resin. Preferably, it is more preferably 0.05 parts by mass or more, still more preferably 0.08 parts by mass or more, preferably 0.5 parts by mass or less, and preferably 0.3 parts by mass or less More preferably, it is 0.25 parts by mass or less. If the content of hydrogenated styrene-conjugated diene block copolymer is at least the above lower limit, the transparency of a container molded using the resin composition for containers can be further improved. Further, if the content of hydrogenated styrene-conjugated diene block copolymer is equal to or less than the above upper limit, the moisture resistance of a container molded using the resin composition for containers can be further improved.

(Method for preparing resin composition for container)
The method for preparing the resin composition for containers of the present invention is not particularly limited. A suitable preparation method includes, for example, a method of kneading the above components in a molten state, and then obtaining a resin composition in the form of pellets. At that time, as a device used for melting and kneading, known devices such as open type mixing rolls, non-open type Banbury mixers, extruders, kneaders, and continuous mixers can be used.
Here, the temperature during melt-kneading is not particularly limited, but is preferably 180° C. or higher, more preferably 200° C. or higher, still more preferably 220° C. or higher, preferably 350° C. or lower, and 320° C. or lower. More preferably, 300° C. or less is even more preferable.

The method for molding a container using the resin composition for containers of the present invention is not particularly limited, and known molding methods can be used.

EXAMPLES The present invention will be specifically described below based on examples, but the present invention is not limited to these examples. In the following description, "%" and "parts" representing amounts are based on mass unless otherwise specified.
In Examples and Comparative Examples, various physical properties were measured and evaluated according to the following methods.

<Glass transition temperature>
The glass transition temperature of the cyclic olefin-based resin obtained in each production example was measured using a differential scanning calorimeter (DSC7000X, manufactured by Hitachi High-Tech Science Co., Ltd.) based on JIS K7121 under the conditions of a heating rate of 10 ° C./min. measured in

<Hydrogenation rate>
¹ H-NMR measurement was performed to determine the hydrogenation rate of the hydrogenated product of the ring-opening polymer of the cyclic olefin.

<Number average molecular weight (Mn)>
The number average molecular weight (Mn) of the processing aids used in Examples and Comparative Examples was determined by using a gel permeation chromatography (GPC) system HLC-8320 (manufactured by Tosoh Corporation) with an H type column (manufactured by Tosoh Corporation). Measured by gel permeation chromatography (GPC) using tetrahydrofuran as a developing solvent at a temperature of 40° C., and calculated as a standard polystyrene conversion value.

<Molding of color plate test piece>
Color plate test pieces were molded using the resin compositions prepared in Examples and Comparative Examples. At this time, molding was performed under the following conditions.
Pre-drying temperature of resin composition: (Tg-20) ° C.
Pre-drying time: 4 hours Drying conditions: Vacuum drying Injection molding machine: Roboshot α-100B manufactured by Fanuc Corporation
Mold: length 65mm, width 65mm, thickness 3mm
Cylinder temperature: (Tg + 140) ° C.,
Mold temperature: (Tg-10) ℃
Injection pressure: 70MPa
In each of the pre-drying temperature, the cylinder temperature, and the mold temperature of the resin composition, "Tg" is the temperature of the cyclic olefin resin contained in the resin compositions obtained in Examples and Comparative Examples. It refers to the glass transition temperature.

<Molding of 96-well plate>
Using the resin compositions prepared in Examples and Comparative Examples, five 96-well plates were molded as waste shots. At this time, molding was performed under the following conditions.
Pre-drying temperature of resin composition: (Tg-20) ° C.
Pre-drying time: 4 hours Pre-drying conditions: Vacuum drying Injection molding machine: J110EL III manufactured by JSW
Mold: Mold for 96-well plate (according to ANSI/SBS standard) Cylinder temperature: (Tg + 160) ° C
Mold temperature: (Tg-40) ℃
Injection pressure: 80MPa
In each of the pre-drying temperature, the cylinder temperature, and the mold temperature of the resin composition, "Tg" is the cyclic olefin resin contained in each resin composition obtained in Examples and Comparative Examples. refers to the glass transition temperature of
Then, under the above conditions, 20 96-well plates similar to the above were molded.

<Light transmittance>
For the color plate test piece molded as described above, the total light transmittance was measured using a turbidity meter (NDH 300A manufactured by Nippon Denshoku Industries Co., Ltd.) according to the method of JIS K7105. And it evaluated according to the following references|standards. The higher the total light transmittance, the higher the transparency of the container molded using the container resin composition.
A: total light transmittance of 90% or more B: total light transmittance of 80% or more and less than 90% C: total light transmittance of 70% or more and less than 80%

<Haze change after steam sterilization>
The haze of the color plate test piece molded as described above was measured using a haze meter (manufactured by Nippon Denshoku Industries Co., Ltd., product name "NDH 2000") to obtain a haze value (H1). After measuring the haze, this color plate test piece was subjected to steam sterilization at 121° C. for 20 minutes using an autoclave (SX-700, manufactured by Tomy Industry Co., Ltd.). After steam sterilization, the color plate specimen was taken out and allowed to stand at 25° C. for 72 hours. Then, the haze was measured for the color plate test piece after steam sterilization to obtain the haze value (H2), and the haze change (ΔH) was calculated based on the following formula.
ΔH = H2 - H1
And it evaluated according to the following references|standards. It means that the smaller the haze change (ΔH) point, the better the steam sterilization resistance of the container molded using the resin composition.
A: ΔH is less than or equal to 0.5 points B: ΔH is more than 0.5 points and less than or equal to 1 point C: ΔH is more than 1 point and less than or equal to 3 points

<Dimensional change after steam sterilization>
Place the color plate test piece molded as described above on a flat surface, fix any one corner so that it contacts the flat surface, and there is no gap between the other three corners and the flat surface It was confirmed. Then, the color plate test piece was subjected to steam sterilization at 121° C. for 20 minutes using a high-pressure steam sterilizer (SX-700, manufactured by Tomy Industry Co., Ltd.). After steam sterilization, the color plate specimen was taken out and allowed to stand at 25° C. for 72 hours. Place the color plate test piece after steam sterilization on the flat surface again, fix any one corner so that it is in contact with the flat surface, and measure the gap between the other three corners and the flat surface with a feeler gauge. It was measured. The largest value among the gaps measured at three locations was taken as the dimensional change value. And it evaluated according to the following references|standards. A smaller dimensional change value means that a container molded from the resin composition is less susceptible to dimensional change after steam sterilization at a high temperature and has excellent steam sterilization resistance.
A: Dimensional change value of 100 μm or less B: Dimensional change value of more than 100 μm and 200 μm or less C: Dimensional change value of more than 200 μm and 500 μm or less D: Dimensional change value of more than 500 μm

<Yellowness>
The yellowness index (YI: yellow index) of the color plate test piece molded as described above is measured in transmission mode using a color difference meter (manufactured by Nippon Denshoku Industries Co., Ltd., SE 2000) in accordance with JISK7373. to obtain the yellowness index (ΔδYI1). At this time, the yellowness index of only air was measured as a blank. Next, the color plate test piece was placed in a constant temperature bath at a temperature of 100 ° C. for 100 hours to perform a heat resistance test, and then the yellowness was measured in the same manner as above to obtain the yellowness (ΔδYI2). Then, the degree of yellowing (ΔδYI) was determined based on the following formula.
ΔδYI=ΔδYI2−ΔδYI1
And it evaluated according to the following references|standards. A smaller value of yellowing index (ΔδYI) means that a container molded using the resin composition has higher transparency.
A: ΔδYI is 0.5 or less B: ΔδYI is more than 0.5 and 1 or less

<Moldability>
The appearance of 20 96-well plates molded as described above was observed, and the number of well plates with molding defects (cracks, warpage, sink marks, voids, etc.) was confirmed. And it evaluated according to the following references|standards. It means that the smaller the number of well plates with molding defects, the better the moldability of the resin composition.
A: The number of well plates with molding defects is 0 B: The number of well plates with molding defects is 1 to 2 C: The number of well plates with molding defects is 3 to 5 D: Molding defects 6 or more well plates with

(Production Example 1) Hydrogenated Product A of Ring-Opening Polymer of Cyclic Olefin
Under a nitrogen atmosphere, 0.82 parts of 1-hexene, 0.15 parts of dibutyl ether, and 0.30 parts of triisobutylaluminum were added to 500 parts of dehydrated cyclohexane in a reactor at room temperature (25°C) and mixed. While maintaining at 45 ° C., 40 parts of tetracyclo[4.4.0.12,5.17,10]dodeca-3-ene (hereinafter referred to as "TCD"), tetracyclo[7.4.0.02, 7.110,13] 60 parts of tetradeca-2,4,6,11-tetraene (hereinafter also referred to as “MTF”) and 40 parts of tungsten hexachloride (0.7% toluene solution) as a polymerization catalyst , were continuously added in parallel over 2 hours to polymerize to obtain a polymerization solution. Then, 1.06 parts of butyl glycidyl ether and 0.52 parts of isopropyl alcohol were added to the polymerization solution to deactivate the polymerization catalyst and terminate the polymerization reaction to obtain a reaction solution containing a ring-opening polymer. Gas chromatography analysis of the resulting reaction solution containing the ring-opening polymer revealed that the polymerization conversion rate of each monomer was 99.6%.
Then, 270 parts of cyclohexane as a solvent was added to 100 parts of the reaction solution containing the obtained ring-opening polymer, and a diatomaceous earth-supported nickel catalyst (Nissan Girdler G-96D; nickel-supported catalyst) was added as a hydrogenation catalyst. of 58%), pressurized to 5 MPa with hydrogen, heated to 200° C. with stirring, reacted for 8 hours, and the reaction solution containing the hydrogenated TCD/MTF ring-opening copolymer was obtained. Obtained. This reaction solution is filtered under pressure at a filter pressure of 0.25 MPa using a filter (Funda filter, manufactured by Ishikawajima-Harima Heavy Industries, Ltd.) using diatomaceous earth ("Radiolite #500" manufactured by Showa Chemical Industry Co., Ltd.) as a filter bed. to remove the hydrogenation catalyst. Next, using a cylindrical concentrating dryer (manufactured by Hitachi, Ltd.), the reaction solution is subjected to a temperature of 270° C. and a pressure of 1 kPa or less to remove the solvent cyclohexane and other volatile components, and then melt the hydrogenated product. The mixture was extruded from an extruder in this state in the form of a strand, cooled and then pelletized to obtain a hydrogenated product A of a ring-opening polymer of a cyclic olefin.
The hydrogenated product A of the pelletized ring-opened cyclic olefin polymer had a hydrogenation rate of 99.9% and a glass transition temperature of 161°C.

(Production Example 2) Hydrogenated product B of ring-opening polymer of cyclic olefin
Under a nitrogen atmosphere, 0.82 parts of 1-hexene, 0.15 parts of dibutyl ether, and 0.30 parts of triisobutylaluminum were added to 500 parts of dehydrated cyclohexane in a reactor at room temperature (25°C) and mixed. While maintaining the temperature at 45° C., 76 parts of tricyclo[4.3.0.12,5]deca-3,7-diene (hereinafter referred to as “DCP”) and tetracyclo[4.4.0.12,5. 17,10]dodeca-3-ene (TCD) 70 parts, tetracyclo[7.4.0.02,7.110,13]tetradeca-2,4,6,11-tetraene (MTF) 54 parts, In parallel, 80 parts of tungsten hexachloride (0.7% toluene solution) as a polymerization catalyst was continuously added over 2 hours for polymerization to obtain a polymerization solution. Then, 1.06 parts of butyl glycidyl ether and 0.52 parts of isopropyl alcohol were added to the polymerization solution to deactivate the polymerization catalyst and terminate the polymerization reaction to obtain a reaction solution containing a ring-opening polymer. Gas chromatography analysis of the resulting reaction solution containing the ring-opening polymer revealed that the polymerization conversion rate of each monomer was 99.5%.
Then, 270 parts of cyclohexane was added to 100 parts of the reaction solution containing the obtained ring-opening polymer, and a diatomaceous earth-supported nickel catalyst (G-96D manufactured by Nissan Girdler Co., Ltd.; nickel support rate of 58%) was added as a hydrogenation catalyst. ), pressurized to 5 MPa with hydrogen, heated to 200° C. with stirring, and reacted for 8 hours to obtain a reaction solution containing a hydrogenated DCP/TCD/MTF ring-opening copolymer. rice field. After removing the hydrogenation catalyst from this reaction solution in the same manner as in Production Example 1, pellets of the hydrogenated product B of the ring-opening polymer of cyclic olefin were obtained.
The hydrogenated product B of the pelletized ring-opened cyclic olefin polymer had a hydrogenation rate of 99.8% and a glass transition temperature of 136°C.

(Production Example 3) Copolymer C of cyclic olefin and chain olefin
120 kg of bicyclo[2.2.1]hept-2-ene (hereinafter referred to as “NB”) was added to a reaction vessel charged with 258 L of cyclohexane at room temperature (25° C.) under a nitrogen stream, and the mixture was stirred for 5 minutes. rice field. Furthermore, triisobutylaluminum was added as a catalyst so that the concentration in the system was 1.0 mL/L. Then, while stirring, ethylene was circulated at normal pressure to create an ethylene atmosphere in the system. The internal temperature of the autoclave was kept at 70° C., and the internal pressure was increased to 6 kg/cm ² in gauge pressure with ethylene. After stirring for 10 minutes, 0.4 L of a toluene solution containing isopropylidene (cyclopentadienyl) (indenyl) zirconium dichloride and methylalumoxane prepared as a catalyst prepared in advance was added to the system to obtain a reaction between ethylene and NB. A copolymerization reaction was initiated. At this time, the catalyst concentration was 0.018 mmol/L for isopropylidene(cyclopentadienyl)(indenyl)zirconium dichloride and 8.0 mmol/L for methylalumoxane with respect to the entire system. During the polymerization, the temperature was kept at 70° C. and the internal pressure was kept at 6 kg/cm ² in gauge pressure by continuously supplying ethylene into the system. After 60 minutes, the polymerization reaction was terminated by adding isopropyl alcohol to obtain a polymerization solution. After depressurization, the polymerization solution was taken out, and this polymerization solution was brought into contact with an aqueous solution of 5 L of concentrated hydrochloric acid added to 1 m ³ of water at a ratio of 1:1 with strong stirring to transfer the catalyst residue to the aqueous phase. , to obtain a contact mixture. After this contact mixture was allowed to stand, the aqueous phase was separated and removed, and further washed with water twice to purify and separate the organic phase.
Next, the purified and separated polymerization solution was brought into contact with 3 times the amount of acetone under strong stirring to precipitate the copolymer, and then the solid portion (copolymer) was collected by filtration and thoroughly washed with acetone. Furthermore, in order to extract unreacted monomers present in the copolymer, this solid portion was put into acetone so as to be 40 kg/m ³ and then subjected to an extraction operation at 60° C. for 2 hours. . After the extraction treatment, the solid portion was collected by filtration and dried at 130° C. and 350 mmHg for 12 hours under a stream of nitrogen to obtain a copolymer C of cyclic olefin and linear olefin.
Then, in the same manner as in Production Example 1, pellets of copolymer C of cyclic olefin and linear olefin were obtained.
The pelletized copolymer C of cyclic olefin and chain olefin had a glass transition temperature of 138°C.

(Production Example 4) Hydrogenated product D of ring-opening polymer of cyclic olefin
250 parts of dehydrated cyclohexane was added to a reactor at room temperature (25°C) and a nitrogen atmosphere, and then 0.84 parts of 1-hexene, 0.06 parts of dibutyl ether and 0.11 parts of triisobutylaluminum were added and mixed. , while maintaining at 45 ° C., tricyclo[4.3.0.12,5]deca-3,7-diene (DCP) 85 parts, 8-ethyltetracyclo[4.4.0.12,5.17, 10] 15 parts of dodeca-3-ene and 15 parts of tungsten hexachloride (0.7% toluene solution) as a polymerization catalyst are continuously added over 2 hours to polymerize, and a reaction containing a ring-opening polymer A solution was obtained. Gas chromatography analysis of the resulting reaction solution containing the ring-opening polymer revealed that the polymerization conversion rate of each monomer was 100%.
The reaction solution containing the resulting ring-opening polymer was transferred to a pressure-resistant hydrogenation reactor, and a diatomaceous earth-supported nickel catalyst (Nissan Girdler "G-96D" as a hydrogenation catalyst; nickel support rate of 58% ) and 100 parts of cyclohexane were added and reacted at 150° C. and hydrogen pressure of 4.4 MPa for 8 hours. After removing the hydrogenation catalyst from this reaction solution in the same manner as in Production Example 1, pellets of the hydrogenated product D of the ring-opening polymer of the cyclic olefin were obtained.
The pelletized hydrogenated product D of the ring-opening copolymer of cyclic olefin had a hydrogenation rate of 99.6% and a glass transition temperature of 102°C.

(Example 1)
<Preparation of resin composition>
100 parts of a hydrogenated product A of a ring-opening polymer of a cyclic olefin as a cyclic olefin-based resin, and polyethylene (1) (manufactured by Baker Hughes Co., Ltd. , trade name "POLYWAX 2000", number average molecular weight (Mn): 2,000) 0.2 parts, and 0.1 part of hydrogenated styrene-conjugated diene block copolymer (manufactured by Asahi Kasei Corporation, trade name "Tuftec H 1051") After mixing the above parts, they were kneaded at 270° C. and 100 rpm using a kneader (manufactured by Toshiba Machine Co., Ltd., trade name “TEM-35B”) to obtain a resin composition (resin composition for containers).
A color plate test piece and a 96-well plate were molded using the obtained resin composition. Then, using the obtained color plate test piece and 96-well plate, light transmittance, haze change after steam sterilization, dimensional change after steam sterilization, yellowing degree, and moldability were evaluated. Table 1 shows the results.

(Example 2)
Hydrogenated polybutene (manufactured by NOF Corporation, trade name "Polybutene 10SH", number average molecular weight (Mn): 1,000) is used instead of polyethylene as a chain hydrocarbon-based processing aid composed of chain saturated hydrocarbons. bottom. Also, the blending amount of the chain hydrocarbon-based processing aid was changed to 1 part with respect to 100 parts of the cyclic olefin-based resin. Furthermore, the blending amount of hydrogenated styrene-conjugated diene block copolymer was changed to 0.2 parts per 100 parts of cyclic olefin resin. A resin composition (resin composition for containers) was prepared in the same manner as in Example 1 except for the above.
Then, using the obtained resin composition, a color plate test piece and a 96-well plate were molded in the same manner as in Example 1, and various evaluations were performed using the obtained color plate test piece and 96-well plate. rice field. Table 1 shows the results.

(Example 3)
As a processing aid, polybutene (manufactured by NOF Corporation, product The name "Polybutene 10N", number average molecular weight (Mn): 1,000) was used. Also, the blending amount of the chain hydrocarbon-based processing aid was changed to 0.5 parts with respect to 100 parts of the cyclic olefin-based resin. A resin composition (resin composition for containers) was prepared in the same manner as in Example 1 except for the above.
Then, using the obtained resin composition, a color plate test piece and a 96-well plate were molded in the same manner as in Example 1, and various evaluations were performed using the obtained color plate test piece and 96-well plate. rice field. Table 1 shows the results.

(Example 4)
As the cyclic olefin resin, the cyclic olefin resin B was used in place of the cyclic olefin resin A. Polyethylene (2) (manufactured by Baker Hughes, trade name "POLYWAX600", number average molecular weight (Mn): 600) was used instead of polyethylene (1) as a chain hydrocarbon-based processing aid. The blending amount of polyethylene (2) was set to 3 parts with respect to 100 parts of cyclic olefin resin B. Furthermore, the blending amount of the hydrogenated styrene-conjugated diene block copolymer was changed to 0.3 parts per 100 parts of the cyclic olefin resin. A resin composition (resin composition for containers) was prepared in the same manner as in Example 1 except for the above.
Then, using the obtained resin composition, a color plate test piece and a 96-well plate were molded in the same manner as in Example 1, and various evaluations were performed using the obtained color plate test piece and 96-well plate. rice field. Table 1 shows the results.

(Example 5)
As the cyclic olefin resin, the cyclic olefin resin C was used in place of the cyclic olefin resin A. Polyethylene (3) (manufactured by Baker Hughes, trade name “POLYWAX1000”, number average molecular weight (Mn): 1000) was used instead of polyethylene (1) as a chain hydrocarbon-based processing aid. The blending amount of polyethylene (3) was set to 0.5 parts per 100 parts of the cyclic olefin resin. Additionally, no styrene-conjugated diene block copolymer hydride was used. A resin composition (resin composition for containers) was prepared in the same manner as in Example 1 except for the above.
Then, using the obtained resin composition, a color plate test piece and a 96-well plate were molded in the same manner as in Example 1, and various evaluations were performed using the obtained color plate test piece and 96-well plate. rice field. Table 1 shows the results.

(Comparative example 1)
As the cyclic olefin resin, the cyclic olefin resin D was used in place of the cyclic olefin resin A. A resin composition was prepared in the same manner as in Example 1 except for the above.
Then, using the obtained resin composition, a color plate test piece and a 96-well plate were molded in the same manner as in Example 1, and various evaluations were performed using the obtained color plate test piece and 96-well plate. rice field. Table 1 shows the results.

(Comparative example 2)
A resin composition was prepared in the same manner as in Example 1, except that no chain hydrocarbon-based processing aid was used.
Then, using the obtained resin composition, a color plate test piece and a 96-well plate were molded in the same manner as in Example 1, and various evaluations were performed using the obtained color plate test piece and 96-well plate. rice field. Table 1 shows the results.

(Comparative Example 3)
As a processing aid, polyethylene glycol (manufactured by Sanyo Chemical Co., Ltd., trade name “PEG-600”, number average molecular weight (Mn)), which is a non-chain hydrocarbon processing aid, is used instead of the chain hydrocarbon processing aid. :600) was used. In addition, the blending amount of the non-chain hydrocarbon-based processing aid was set to 1 part with respect to 100 parts of the cyclic olefin-based resin. A resin composition was prepared in the same manner as in Example 1 except for the above.
Then, using the obtained resin composition, a color plate test piece and a 96-well plate were molded in the same manner as in Example 1, and various evaluations were performed using the obtained color plate test piece and 96-well plate. rice field. Table 1 shows the results.

(Comparative Example 4)
A resin composition was prepared in the same manner as in Example 1, except that the amount of the chain hydrocarbon-based processing aid was changed to 12 parts per 100 parts of the cyclic olefin resin.
Then, using the obtained resin composition, a color plate test piece and a 96-well plate were molded in the same manner as in Example 1, and various evaluations were performed using the obtained color plate test piece and 96-well plate. rice field. Table 1 shows the results.

(Comparative Example 5)
As a chain hydrocarbon-based processing aid, polyethylene (4) (manufactured by Sanyo Kasei Co., Ltd., trade name “Sanwax 161-P”, number average molecular weight (Mn): 6,800) was used instead of polyethylene (1). A resin composition was prepared in the same manner as in Example 1, except that it was used.
Then, using the obtained resin composition, a color plate test piece and a 96-well plate were molded in the same manner as in Example 1, and various evaluations were performed using the obtained color plate test piece and 96-well plate. rice field. Table 1 shows the results.

In addition, in Table 1,
"Resin A" represents a hydrogenated product A of a ring-opening polymer of a cyclic olefin,
"Resin B" indicates a hydrogenated product B of a ring-opening polymer of a cyclic olefin,
"Resin C" represents a copolymer C of a cyclic olefin and a chain olefin,
"Resin D" represents a hydrogenated product D of a ring-opening polymer of a cyclic olefin,
"PE" indicates polyethylene;
"PEG" indicates polyethylene glycol.

From Table 1, a cyclic olefin-based resin and a chain hydrocarbon-based processing aid are contained in a predetermined ratio with respect to the cyclic olefin-based resin, and the glass transition temperature of the cyclic olefin-based resin is within a predetermined range. It can be seen that the resin compositions of Examples 1 to 4, in which the number average molecular weight of the hydrocarbon-based processing aid is within a predetermined range, are excellent in moldability. Moreover, it is found that by using the resin compositions of Examples 1 to 4, containers having excellent transparency and steam sterilization resistance can be molded.

ADVANTAGE OF THE INVENTION According to this invention, the resin composition for containers which is excellent in moldability and can be molded into a container excellent in transparency and resistance to steam sterilization can be provided.

Claims (3)

a cyclic olefin-based resin;
A resin composition for containers containing a chain hydrocarbon-based processing aid in an amount of 0.01 parts by mass or more and 10 parts by mass or less relative to 100 parts by mass of the cyclic olefin resin,
The cyclic olefin resin has a glass transition temperature (Tg) of 125° C. or higher and 200° C. or lower,
A resin composition for a container, wherein the chain hydrocarbon-based processing aid has a number average molecular weight (Mn) of 100 or more and 5,000 or less. 2. The container resin according to claim 1, further comprising a hydrogenated styrene-conjugated diene block copolymer in a proportion of 0.01 parts by mass or more and 0.5 parts by mass or less with respect to 100 parts by mass of the cyclic olefin resin. Composition. 3. The resin composition for containers according to claim 1, wherein said chain hydrocarbon-based processing aid comprises a chain saturated hydrocarbon.