JP2013048560A - Culture vessel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a culture vessel for culturing harvested microorganisms, animal and plant tissues and the like by adding a culture medium to the harvested microorganisms, animal and plant tissues and the like, excellent in transparency, flexibility and steam sterilizability.SOLUTION: The culture vessel is formed of a hydrogenated block copolymer prepared by hydrogenating ≥90% total unsaturated bonds of a copolymer comprising at least two polymer blocks [A] with an aromatic vinyl compound-derived repeating unit as a main ingredient and at least one polymer block [B] with a chain conjugated diene compound-derived repeating unit as a main ingredient, and satisfying the ratio of wA to wB (wA:wB) to be 30:70-60:40, wherein wA represents a weight fraction of the total polymer blocks [A] in the whole block copolymer and wB represents a weight fraction of the total polymer blocks [B] in the whole block copolymer.

Description

  The present invention relates to a culture container, and more specifically, a culture container excellent in transparency, flexibility, and steam sterilization resistance for culturing microorganisms, animal and plant tissues by adding a medium to the collected microorganisms, animal and plant tissues. About.

  Disposable bioreactors as culture vessels are devices that use plastic sterilized containers and bags, and are used to process biological materials (for example, to cultivate microorganisms, animal and plant tissues, etc.) Is done. A disposable bioreactor includes a support structure made of metal, wood, and the like, and a flexible plastic container disposed in the support structure, a flexible plastic bag, a feed tube, a sampling port, and a filter. There are things with a vent with a filter and an exhaust with a filter. These disposable bioreactors are in the form of flexible plastic bags with a capacity of 1 to 5 liters for small ones and stainless steel support structures with a capacity of 10 to 2000 liters for large ones. The thing provided with the flexible plastic bag etc. are used.

Plastic films or sheets for forming flexible plastic bags are required to have acid / alkali resistance, flexibility, fusion by high frequency fusion or heat fusion, and other polyolefin-based materials such as polypropylene and polyethylene. Are preferably used.

However, for example, in the case of polypropylene proposed in Patent Documents 1 and 2 and the like, it has excellent heat resistance and can be sterilized at 125 ° C. for 30 minutes or more, but has a high elastic modulus and poor flexibility. However, the transparency is remarkably low and the content visibility is inferior. In addition, for example, polyethylene proposed in Patent Documents 3 to 4 has excellent flexibility, but has low heat resistance and cannot withstand high-pressure steam sterilization, so γ-ray sterilization or electron beam sterilization is necessary. In addition, since it is a crystalline polymer like polypropylene, the thick-walled bag has problems such as low transparency and poor content visibility.

Patent Document 5 proposes a cell culture bag made of a polymer mixture comprising a poly (ethylene butylene) polystyrene block copolymer / polypropylene / ethylene acrylate copolymer, which has good transparency and high-pressure steam sterilization. However, it is described that it does not deform. However, what is disclosed is an example of a small cell culture bag having a thickness of about 150 cc and a thin sheet having a thickness of about 150 μm, and transparency in a thicker, large-capacity container is not shown. Moreover, it is unclear whether high-pressure steam sterilization is possible in the presence of the content liquid.

  Patent Document 6 discloses a multilayer film using a vinylcyclohexane-based polymer and describes that it can be used for packaging materials and flexible containers. However, the disclosed block copolymer has a high ratio of vinylcyclohexane block to the whole polymer of 65 to 97% by weight, and is a low-flexibility block copolymer. It does not balance heat resistance.

Japanese Utility Model Publication No. 1-99200 Japanese Patent Laid-Open No. 5-219834 JP-A-3-277268 JP 2005-245424 A JP-A-3-65177 Special table 2003-517951

The present invention has been made in view of such circumstances, and is excellent in flexibility, high-frequency fusion or fusion by heat fusion, etc., has high heat resistance, can be sterilized under high pressure steam, and has high transparency and excellent contents. It aims at providing the culture container which has visibility.

As a result of diligent studies to improve the drawbacks of these prior arts, the present inventor has found that at least two polymer blocks [A] mainly composed of a repeating unit derived from a specific aromatic vinyl compound, and a chain conjugated diene. It is formed from a block copolymer hydride obtained by hydrogenating 90% or more of all unsaturated bonds of a block copolymer composed of at least one polymer block [B] having a repeating unit derived from a compound as a main component. Is used as a container for culturing microorganisms, animal and plant tissues, etc., is highly transparent, has excellent contents visibility, has high heat resistance and is capable of steam sterilization, and has flexibility, high-frequency fusion and heat fusion. The inventors have found that a culture vessel excellent in fusion property, oxygen permeability, and the like by adhesion can be obtained, and the present invention has been achieved.

  Thus, according to the present invention, at least two polymer blocks [A] having a repeating unit derived from an aromatic vinyl compound as a main component and at least 1 having a repeating unit derived from a chain conjugated diene compound as a main component. The weight fraction of all polymer blocks [A] in the whole block copolymer is wA, and the weight fraction of all polymer blocks [B] in the whole block copolymer is comprised of two polymer blocks [B]. A block copolymer obtained by hydrogenating 90% or more of all unsaturated bonds of a block copolymer in which the ratio of wA to wB (wA: wB) is 30:70 to 60:40 when the rate is wB A container for culturing microorganisms, animal and plant tissues formed from hydrides is provided.

The block copolymer hydride used in the present invention has a polymer block [A] having a high glass transition temperature and excellent heat resistance, and a polymer block [B] having a low glass transition temperature and excellent flexibility. It is amorphous and has low moisture absorption, low moisture permeability, acid resistance and alkali resistance. By using such a block copolymer hydride, the transparency is high and the contents are visible. It is possible to provide a culture vessel that is excellent in heat resistance, high in heat resistance and capable of high-pressure steam sterilization, and excellent in flexibility, fusion by high frequency fusion or heat fusion, oxygen permeability, and the like. Moreover, the culture container of the present invention is non-toxic to microorganisms, animal and plant tissues and the like.

It is a top view which shows the container for culture | cultivation described in Example 1 and 2 of this invention.

The culture vessel of the present invention is formed by molding a block copolymer hydride obtained by hydrogenating a carbon-carbon unsaturated bond of a specific block copolymer.

1. Block Copolymer The block copolymer used in the present invention contains at least two polymer blocks [A] and at least one polymer block [B].

  The polymer block [A] is mainly composed of a structural unit derived from an aromatic vinyl compound, and the content of the structural unit derived from the aromatic vinyl compound in the polymer block [A] is usually 90% by weight. Above, preferably 95% by weight or more, more preferably 99% by weight or more. Further, the component other than the structural unit derived from the aromatic vinyl compound in the polymer block [A] can include a structural unit derived from a chain conjugated diene and / or a structural unit derived from another vinyl compound, The content is usually 10% by weight or less, preferably 5% by weight or less, more preferably 1% by weight or less. When there are too few structural units derived from the aromatic vinyl compound in the polymer block [A], the heat resistance of the resin composition of the present invention may be lowered.

  The plurality of polymer blocks [A] may be the same as or different from each other as long as the above range is satisfied.

  The polymer block [B] is mainly composed of a structural unit derived from a chain conjugated diene compound, and the content of the structural unit derived from the chain conjugated diene compound in the polymer block [B] is usually 50. % By weight or more, preferably 70% by weight or more, more preferably 90% by weight or more. When the structural unit derived from the chain conjugated diene compound is in the above range, the resin composition of the present invention is excellent in the balance of flexibility, fusion property by high frequency fusion or thermal fusion. Moreover, as a component other than the structural unit derived from the chain conjugated diene compound in the polymer block [B], a structural unit derived from an aromatic vinyl compound and / or a structural unit derived from another vinyl compound can be included, Its content is usually 30% by weight or less, preferably 10% by weight or less. As the content of the structural unit derived from the aromatic vinyl compound in the polymer block [B] increases, the transparency of the resin composition of the present invention is improved. There is a possibility that the flexibility of the composition is lowered and the fusion property by high frequency fusion or heat fusion is lowered.

  When there are a plurality of polymer blocks [B], the polymer blocks [B] may be the same as or different from each other as long as the above range is satisfied.

  Specific examples of the aromatic vinyl compound used in the present invention include styrene, α-methylstyrene, 2-methylstyrene, 3-methylstyrene, 4-methylstyrene, 2,4-diisopropylstyrene, 2,4- Dimethylstyrene, 4-t-butylstyrene, 5-t-butyl-2-methylstyrene, 4-monochlorostyrene, dichlorostyrene, 4-monofluorostyrene, 4-phenylstyrene and the like are polar in terms of hygroscopicity Those containing no groups are preferred, and styrene is particularly preferred.

Specific examples of the chain conjugated diene compound used in the present invention include 1,3-butadiene, isoprene, 2,3-dimethyl-1,3-butadiene, 1,3-pentadiene, and the like. In view of the properties, those containing no polar group are preferred, and 1,3-butadiene and isoprene are particularly preferred.

Examples of other vinyl compounds used in the present invention include chain vinyl compounds and cyclic vinyl compounds. Specifically, ethylene, propylene, 1-butene, 1-pentene, 1-hexene, 1-heptene, Chain olefins such as 1-octene, 1-nonene, 1-decene, 1-dodecene, 1-eicocene, 4-methyl-1-pentene, 4,6-dimethyl-1-heptene; cyclic olefins such as vinylcyclohexane Those that do not contain a polar group are preferred in terms of acid resistance and alkali resistance, chain olefins are more preferred, and ethylene and propylene are particularly preferred.

The number of polymer blocks [A] in the block copolymer used in the present invention is usually 5 or less, preferably 4 or less, more preferably 3 or less. When there are a plurality of polymer blocks [A] and / or polymer blocks [B], the weight average molecular weight of the polymer block having the maximum and minimum weight average molecular weight in the polymer block [A] is expressed as Mw (A1 ) And Mw (A2), and when the weight average molecular weight of the polymer block having the largest and smallest weight average molecular weight in the polymer block [B] is Mw (B1) and Mw (B2), respectively, the Mw ( The ratio between A1) and Mw (A2) (Mw (A1) / Mw (A2)) and the ratio between Mw (B1) and Mw (B2) (Mw (B1) / Mw (B2)) Each is usually 2.0 or less, preferably 1.5 or less, more preferably 1.2 or less.

The form of block of the block copolymer used in the present invention may be a chain type block or a radial type block, but a chain type block is preferred because of excellent mechanical strength. The most preferred form of the block copolymer of the present invention is a triblock copolymer in which the polymer block [A] is bonded to both ends of the polymer block [B], and a polymer on both ends of the polymer block [A]. It is a pentablock copolymer in which the block [B] is bonded and the polymer block [A] is bonded to the other end of the both polymer blocks [B].

In the block copolymer used in the present invention, the weight fraction of the whole polymer block [A] in the whole block copolymer is wA, and the weight of the whole polymer block [B] in the whole block copolymer. When the fraction is wB, the ratio of wA to wB (wA: wB) is 30: 70-60: 40, preferably 35: 65-55: 45, more preferably 40: 60-50: 50. is there. When wA is too high, the heat resistance of the resin composition of the present invention is increased, but the flexibility is low, the fusion property by high frequency fusion or heat fusion is lowered, and when wA is too low, steam sterilization is performed. Heat resistance at is poor.

  The molecular weight of the block copolymer is a polystyrene-reduced weight average molecular weight (Mw) measured by GPC using THF (tetrahydrofuran) as a solvent, and is usually 30,000 to 200,000, preferably 40,000 to 150,000. More preferably, it is 50,000-100,000. The molecular weight distribution (Mw / Mn) of the block copolymer is preferably 3 or less, more preferably 2 or less, and particularly preferably 1.5 or less.

  In the production method of the block copolymer used in the present invention, for example, when producing a block copolymer having three polymer blocks, an aromatic vinyl compound is contained as a monomer component for forming the polymer block [A]. A first step of polymerizing the monomer mixture (a1) to be polymerized, a second step of polymerizing the monomer mixture (b1) containing a chain conjugated diene compound as a monomer component for forming the polymer block [B], As a monomer component for forming the combined block [A], a monomer mixture (a2) containing an aromatic vinyl compound (however, the monomer mixture (a1) and the monomer mixture (a2) may be the same or different) is polymerized. A third step to be performed.

  As a method for polymerizing each polymer block using the monomer mixture, any of radical polymerization, anionic polymerization, cationic polymerization, coordinated anionic polymerization, coordinated cationic polymerization and the like may be used. When a method of conducting radical polymerization, anionic polymerization, cationic polymerization, etc. by living polymerization, particularly a method of living anionic polymerization, is used, the hydrogenation reaction in the polymerization operation and the post-process becomes easy, and the resulting block copolymer Improved transparency of coalescence.

  The polymerization is usually carried out in the presence of a polymerization initiator in a temperature range of 0 ° C to 100 ° C, preferably 10 ° C to 80 ° C, particularly preferably 20 ° C to 70 ° C. In the case of living anionic polymerization, as an initiator, for example, monoorganolithium such as n-butyllithium, sec-butyllithium, t-butyllithium, hexyllithium, phenyllithium; dilithiomethane, 1,4-dilithiobutane, 1,4 -Polyfunctional organolithium compounds such as dilithio-2-ethylcyclohexane can be used.

The polymerization reaction form may be either solution polymerization or slurry polymerization. However, when solution polymerization is used, it is easy to remove reaction heat. In this case, an inert solvent in which the polymer obtained in each step is dissolved is used. Examples of the inert solvent that can be used include aliphatic hydrocarbons such as n-butane, n-pentane, isopentane, n-hexane, n-heptane, and isooctane; cyclopentane, cyclohexane, methylcyclopentane, methylcyclohexane, Examples include alicyclic hydrocarbons such as decalin, bicyclo [4.3.0] nonane, and tricyclo [4.3.0.1 ^2,5 ] decane; aromatic hydrocarbons such as benzene and toluene. Among these, alicyclic hydrocarbons are preferable because they can be used as they are as an inert solvent for the hydrogenation reaction described later, and the solubility of the block copolymer is good. These solvents may be used alone or in combination of two or more. The amount of these solvents used is usually 200 to 2000 parts by weight with respect to 100 parts by weight of all the monomers used.

  In the case where each monomer mixture is composed of two or more components, a randomizer or the like can be used in order to prevent only a certain component chain from becoming long. In particular, when the polymerization reaction is performed by anionic polymerization, it is preferable to use a Lewis base compound or the like as a randomizer.

  Examples of usable Lewis base compounds include ether compounds such as dimethyl ether, diethyl ether, diisopropyl ether, dibutyl ether, tetrahydrofuran, diphenyl ether, ethylene glycol diethyl ether, ethylene glycol methyl phenyl ether; tetramethylethylenediamine, trimethylamine, triethylamine, pyridine. And the like; tertiary amine compounds such as potassium-t-amyl oxide, alkali metal alkoxide compounds such as potassium-t-butyl oxide; phosphine compounds such as triphenylphosphine; These Lewis base compounds may be used alone or in combination of two or more.

2. Block copolymer hydride The block copolymer hydride used in the present invention comprises a carbon-carbon unsaturated bond in the main chain and side chain of the block copolymer, and a carbon-carbon unsaturated bond in the aromatic ring. The hydrogenation rate is usually 90% or more, preferably 97% or more, more preferably 99% or more. The higher the hydrogenation rate, the better the transparency and heat resistance of the resin composition of the present invention. The hydrogenation rate of the block copolymer hydride used in the present invention can be determined by measurement by ¹ H-NMR.

  There are no particular restrictions on the hydrogenation method or reaction mode of the unsaturated bond, and it may be carried out according to a known method. However, a hydrogenation method that can increase the hydrogenation rate and has little polymer chain cleavage reaction is preferred. Examples of such a preferable hydrogenation method include a method using a catalyst containing at least one metal selected from nickel, cobalt, iron, titanium, rhodium, palladium, platinum, ruthenium, rhenium and the like. As the hydrogenation catalyst, either a heterogeneous catalyst or a homogeneous catalyst can be used, and the hydrogenation reaction is preferably carried out in an organic solvent.

The heterogeneous catalyst that can be used can be used in the form of a metal or a metal compound or supported on a suitable carrier. Examples of the carrier include activated carbon, silica, alumina, calcium carbonate, titania, magnesia, zirconia, diatomaceous earth, silicon carbide, calcium fluoride and the like. The amount of the catalyst supported is usually 0.1 to 60% by weight, preferably 1 to 50% by weight, based on the total amount of the catalyst and the carrier. As the supported catalyst, for example, a catalyst having a specific surface area of 100 to 500 m ² / g and an average pore diameter of 100 to 1000 mm, preferably 200 to 500 mm is preferable. The value of the specific surface area is a value calculated by measuring the nitrogen adsorption amount and using the BET equation, and the value of the average pore diameter is a value measured by a mercury intrusion method.

  Usable homogeneous catalysts include, for example, catalysts in which nickel, cobalt, titanium or iron compounds and organometallic compounds (for example, organoaluminum compounds, organolithium compounds) are combined; rhodium, palladium, platinum, ruthenium, rhenium, etc. An organometallic complex catalyst or the like can be used.

  Examples of nickel, cobalt, titanium, or iron compounds include acetylacetonate compounds, carboxylates, and cyclopentadienyl compounds of various metals. Examples of the organoaluminum compound include alkylaluminums such as triethylaluminum and triisobutylaluminum; aluminum halides such as diethylaluminum chloride and ethylaluminum dichloride; and alkylaluminum hydrides such as diisobutylaluminum hydride.

  Examples of organometallic complex catalysts include transition metal complexes such as dihydrido-tetrakis (triphenylphosphine) ruthenium, dihydrido-tetrakis (triphenylphosphine) iron, bis (cyclooctadiene) nickel, and bis (cyclopentadienyl) nickel. Is mentioned.

  These hydrogenation catalysts may be used alone or in combination of two or more. The usage-amount of a hydrogenation catalyst is 0.01-100 weight part normally with respect to 100 weight part of polymers, Preferably it is 0.05-50 weight part, More preferably, it is 0.1-30 weight part.

  When the hydrogenation reaction temperature is usually 10 ° C. to 250 ° C., preferably 50 ° C. to 200 ° C., more preferably 80 ° C. to 180 ° C., the hydrogenation rate increases and molecular cleavage also decreases. The hydrogen pressure is usually from 0.1 MPa to 30 MPa, preferably from 1 MPa to 20 MPa, more preferably from 2 MPa to 10 MPa, the hydrogenation rate is increased, molecular chain breakage is reduced, and operability is excellent.

  The block copolymer hydride obtained by the above method is prepared by removing the hydrogenation catalyst and / or the polymerization catalyst from the reaction solution containing the block copolymer hydride by, for example, filtration, centrifugation, or the like. Recovered from. Examples of the method for recovering the block copolymer hydride from the reaction solution include a steam coagulation method in which the solvent is removed by steam stripping from a solution in which the block copolymer hydride is dissolved, and the solvent is removed under reduced pressure heating. Known methods such as a direct desolvation method and a coagulation method in which a solution is poured into a poor solvent of a block copolymer hydride to precipitate and solidify can be exemplified.

  The form of the recovered block copolymer hydride is not limited, but it is usually in the form of a pellet so that it can be easily molded after that. When the direct desolvation method is used, for example, the molten block copolymer hydride can be extruded from a die into a strand shape, cooled, and then cut with a pelletizer into pellets for various moldings. When using the coagulation method, for example, after drying the obtained coagulated product, it is extruded in a molten state by an extruder, and in the same manner as above, pelletized to be used for culture containers such as microorganisms and animal and plant tissues. .

  The molecular weight of the block copolymer hydride used in the present invention is a weight average molecular weight (Mw) in terms of polystyrene measured by GPC using THF as a solvent, and is usually 30,000 to 200,000, preferably 40,000. ˜150,000, more preferably 50,000 to 100,000. When the Mw is in the range, the mechanical strength and heat resistance of the culture container of the present invention are improved. Further, the molecular weight distribution (Mw / Mn) of the block copolymer hydride is preferably 3 or less, more preferably 2 or less, and particularly preferably 1.5 or less. When Mw and Mw / Mn are within the above ranges, the mechanical strength and heat resistance of the block copolymer hydride of the present invention are improved.

3. Formulation agent The block copolymer hydride used in the culture vessel of the present invention contains a formulation component for improving the performance of the culture vessel within a range that does not affect the culture of microorganisms, animal and plant tissues, etc. be able to. Ingredients include antioxidants, ultraviolet absorbers for preventing the death of cultured tissues due to ultraviolet rays, polymers other than the block copolymer hydrides for improving resin properties, lubricants, surfactants, inorganics It is a filler and may be used alone or in combination of two or more. These compounding agents are minimized so as not to elute into the contents of the culture vessel.

[Antioxidant]
In this invention, thermal stability can also be improved by mix | blending antioxidant with a block copolymer hydride. Since the culture container of the present invention is presumed to be disposable, it may be blended to such an extent that it does not undergo oxidative degradation when the block copolymer hydride is heated and melted and formed into a container. Examples of the antioxidant include phosphorus-based antioxidants, phenol-based antioxidants, sulfur-based antioxidants, and the like, and phosphorus-based antioxidants with less coloring are preferable.
[Ultraviolet absorber]
In the present invention, in order to prevent the cultured tissue from being killed by ultraviolet rays, in addition to the above antioxidant, an ultraviolet absorber such as a benzophenone ultraviolet absorber, a salicylic acid ultraviolet absorber, or a benzotriazole ultraviolet absorber is blended. be able to.
[Polymers other than block copolymer hydrides]
Polymers other than block copolymer hydrides that can be blended to improve the characteristics of the culture vessel include olefin polymers such as ethylene / propylene copolymer and propylene / ethylene / 1-butene copolymer; Isobutylene polymers such as isobutylene, isobutylene / isoprene hydride, polyisoprene, isoprene / butadiene random copolymer, butadiene / styrene random copolymer, isoprene / styrene random copolymer, butadiene / styrene block copolymer Hydrides of diene polymers such as polymers, isoprene / styrene block copolymers; petroleum resins such as 1,3-pentadiene petroleum resins, cyclopentadiene petroleum resins, aromatic petroleum resins and their hydrides; Can be mentioned.
[Lubricant]
Lubricants used from the viewpoint of moldability and blocking resistance include hydrocarbon release agents, fatty acid release agents, alcohol release agents; aliphatic ester release agents; fatty acid amide release agents; fatty acids Metal soap release agents; silicone release agents and the like.

  In the method of uniformly dispersing the compounding agent in the block copolymer hydride used in the present invention, for example, the compounding agent is dissolved in a suitable solvent and added to the block copolymer hydride solution, and then the solvent is added. Of removing block copolymer hydride containing compounding agent; kneading compounding agent by melting block copolymer hydride in biaxial kneader, roll, brabender, extruder, etc. Method; and the like.

4). Culture Container The culture container of the present invention is primarily intended for use as a disposable bioreactor. The shape of the container is usually a bag shape, a cylindrical shape, a bag shape or the like, but is not particularly limited. The size of the container is not particularly limited, but usually the inner volume is about 0.1 to 2000 liters. The thickness of the container is not particularly limited, but is usually about 0.1 to 2 mm, preferably about 0.2 to 1 mm. Those that are self-supporting in the container itself can be used as they are, but those that are large in size and are not self-supporting are used by being supported by a metal support structure. The culture vessel of the present invention can also be provided with a feed tube, a sampling port, a filter vent, a filter exhaust port, and the like. An external stirrer can also be attached.

The method for forming the culture vessel is not particularly limited, but usually, a specific block copolymer hydride is formed into a sheet by a molding method such as extrusion molding, calender molding, inflation molding, etc., and the resulting sheet is in a preferred shape. After being cut into pieces, they can be fused and joined together by high-frequency fusion or heat fusion to form a container having a desired shape. Moreover, it can also shape | mold into a container by methods, such as well-known blow molding, injection molding, injection blow molding, extrusion molding, and inflation molding. The molding conditions of the sheet are appropriately selected depending on the molding method. For example, in the case of the melt extrusion molding method, the resin temperature is usually 170 to 250 ° C., preferably 180 to 230 ° C., more preferably 190 to 220 ° C. It is selected appropriately. If the resin temperature is too low, the fluidity deteriorates and the molded sheet is liable to be damaged, such as the skin and die lines. If the resin temperature is too high, decomposition of the block copolymer hydride is caused by thermal decomposition. It is not preferable because it tends to cause defects such as elution of substances, or a decrease in molecular weight and mechanical strength.

Hereinafter, the present invention will be described more specifically with reference to examples and comparative examples. The present invention is not limited only to these examples. In the following examples and comparative examples, parts and% are based on weight unless otherwise specified.

The measurement methods for various physical properties are shown below.
(1) Weight average molecular weight (Mw) and molecular weight distribution (Mw / Mn)
The molecular weights of the block copolymer and the hydride of the block copolymer were measured at 38 ° C. as standard polystyrene conversion values by gel permeation chromatography (GPC) using tetrahydrofuran as an eluent. As a measuring apparatus, HLC8020GPC manufactured by Tosoh Corporation was used.
(2) Hydrogenation rate The hydrogenation rate of the main chain and aromatic ring of the block copolymer hydride was calculated by measuring the ¹ H-NMR spectrum.
(3) Light transmittance measured with block copolymer hydride and resin extruded sheet used in Comparative Example according to JIS K 7361.
(4) JIS K 7171 using a bending tester (Bent Grapho II, manufactured by Toyo Seiki Co., Ltd.) with an injection-molded test piece (thickness: 4 mm) of the flexural modulus block copolymer hydride and the resin used in the comparative example. This was measured under the condition of 23 ° C.
(5) Tensile strength and tensile elongation block copolymer hydride and resin extruded sheet used in Comparative Example, JIS K using Tensilon Universal Tester (product name “RTC-1125A” manufactured by ORIENTIC) It was measured by the method of 7127. The test piece was subjected to a tensile test until it broke at a distance of 10 cm between chucks under the conditions of type 5 and 23 ° C. The strength at break was defined as tensile strength, and the elongation at break was defined as tensile elongation.
(6) The eluate block copolymer hydride and the resin pellets used in the comparative examples were used, and the eluate test was conducted in accordance with the 15th revised Japanese Pharmacopoeia "Plastic Pharmaceutical Container Test Method". Ultraviolet absorption and potassium permanganate reducing substances were evaluated.

[Reference Example 1] Synthesis of block copolymer hydride [P1] In a reactor equipped with a stirrer sufficiently purged with nitrogen, 550 parts of dehydrated cyclohexane, 25.0 parts of dehydrated styrene, 0.475 n-dibutyl ether The polymerization was started by adding 0.68 parts of n-butyllithium (15% cyclohexane solution) while stirring at 60 ° C. The mixture was reacted at 60 ° C. for 60 minutes with stirring. At this point in time as measured by gas chromatography, the polymerization conversion was 99.5%.
Next, 50.0 parts of dehydrated isoprene was added and stirring was continued for 30 minutes. At this time, the polymerization conversion rate was 99%.
Thereafter, 25.0 parts of dehydrated styrene was further added and stirred for 60 minutes. The polymerization conversion rate at this point was almost 100%. Here, 0.5 part of isopropyl alcohol was added to stop the reaction. The obtained block copolymer (p1) had a weight average molecular weight (Mw) of 61,700 and a molecular weight distribution (Mw / Mn) of 1.05.

Next, the polymer solution was transferred to a pressure-resistant reactor equipped with a stirrer, and a silica-alumina supported nickel catalyst (manufactured by JGC Catalysts & Chemicals, product name “E22U”, nickel supported amount 60% as a hydrogenation catalyst) ) 4.0 parts and 100 parts dehydrated cyclohexane were added and mixed. The inside of the reactor was replaced with hydrogen gas, and hydrogen was supplied while stirring the solution. A hydrogenation reaction was carried out at a temperature of 170 ° C. and a pressure of 4.5 MPa for 6 hours. The weight average molecular weight (Mw) of the block copolymer hydride (P1) after the hydrogenation reaction was 65,300, and the molecular weight distribution (Mw / Mn) was 1.06.

After completion of the hydrogenation reaction, the reaction solution was filtered to remove the hydrogenation catalyst, and then a phenol-based antioxidant pentaerythrityl tetrakis [3- (3,5-di-t-butyl-4- Hydroxyphenyl) propionate] (manufactured by BASF, product name “Irganox (registered trademark) 1010”) 1.0 part of xylene solution in which 0.05 part by weight was dissolved was added and dissolved.
Next, the solution is filtered through a Zeta Plus (registered trademark) filter 30H (Cuno, pore size 0.5 to 1 μm), and further with another metal fiber filter (Nichidai Corp., pore size 0.4 μm). After filtering to remove fine solids, using a cylindrical concentrating dryer (manufactured by Hitachi, Ltd.), at a temperature of 260 ° C. and a pressure of 0.001 MPa or less, from the solution, cyclohexane, xylene and other solvents The volatile components were removed, extruded in a strand form in a molten state from a die directly connected to a concentration dryer, cooled, and then cut with a pelletizer to obtain 95 parts of a block copolymer hydride [P1] pellet. The resulting block copolymer hydride [P1] had a weight average molecular weight (Mw) of 64,600 and a molecular weight distribution (Mw / Mn) of 1.11. The hydrogenation rate was almost 100%.

[Example 1]
(Extruded film)
100 parts of the block copolymer hydride [P1] pellets obtained in Reference Example 1 were heated at 50 ° C. for 4 hours using a hot air dryer in which air was circulated to remove dissolved air, and then ethylene. 0.01 parts of bis-stearic acid amide powder (product name “Kao wax EB-P” manufactured by Kao Corporation) was added and mixed uniformly. This pellet was melted at a molten resin temperature of 200 ° C., a T-die temperature of 180 ° C., and a roll temperature of 50 using a T-die film melt extrusion molding machine (T-die width 600 mm) having a resin melt kneader equipped with a 40 mmφ screw. A sheet [SP1] having a thickness of 500 μm and a width of 500 mm was extruded under a molding condition of ° C., and was wound up and collected on a roll.

(Extruded tube)
100 parts of the block copolymer hydride [P1] pellets obtained in Reference Example 1 were heated at 50 ° C. for 4 hours using a hot air dryer in which air was circulated to remove dissolved air, and then ethylene. 0.01 parts of bis-stearic acid amide powder (product name “Kao wax EB-P” manufactured by Kao Corporation) was added and mixed uniformly. A tube extrusion die was placed in a resin melt kneader equipped with a 40 mmφ screw, and the pellets were subjected to a tube [CP1 with an outer diameter of 6 mm and an inner diameter of 4 mm under molding conditions of a molten resin temperature of 190 ° C. and a die temperature of 170 ° C. ] Was extruded, wound up and collected.

(injection molding)
To 100 parts of the block copolymer hydride [P1] pellets obtained in Reference Example 1, 0.01 parts of ethylenebisstearic acid amide powder was added and mixed uniformly as described above. Using this pellet, a test piece [MP1] having a thickness of 4 mm was molded under molding conditions of a resin temperature of 240 ° C. and a mold temperature of 40 ° C. using an injection molding machine.

(Evaluation of resin for culture vessels)
Using the obtained block copolymer hydride [P1] pellets, extruded sheet [SP1], and test piece [MP1], evaluation of light transmittance, flexural modulus, tensile strength, tensile elongation, and eluate was performed. did. The light transmittance was 91%, the flexural modulus was 725 MPa, the tensile strength was 45 MPa, and the tensile elongation was 530%. As a result of the eluate test, foaming disappeared within 3 minutes, pH difference was -0.03, ultraviolet absorption was 0.007, and potassium permanganate reducing substance was 0.15 ml. From these results, the block copolymer hydride [P1] is excellent in transparency, has flexibility and sufficient mechanical strength, has low elution properties, and can be adapted as a medical plastic. It was found that the material has excellent characteristics.

(Culture container)
Using two sheets of extruded sheet [SP1] cut to a length of 600 mm and a width of 250 mm and an extruded tube [CP1], the joint portion was heat-sealed with a heat sealer, and the internal capacity shown in FIG. A culture vessel 1 was prepared. The container can be opened and closed by fusing and fixing a feed tube 2, a sampling tube 3, an exhaust tube 4, and an extraction tube 5 at the bottom, and a metal cock 6 at the end of the tube. I made it.

Next, this culture vessel is fixed to a gantry, and an LB medium (an aqueous solution of 1% bactotryptone, 0.5% yeast extract, 1% sodium chloride, 0.1% glucose is added to pH 7.5 from the feed tube 2. To 4000 ml). This culture container was excellent in transparency and the contents visibility was good.
All the cocks of the culture vessel containing the contents are closed and removed from the gantry, put into a high-pressure steam sterilizer (product name “SX-700” manufactured by Tommy Seiko Co., Ltd.), and high-pressure steam at 2 atm, 121 ° C. for 30 minutes. Sterilization was performed. After cooling to room temperature, the appearance was visually observed, but no deformation or melting was observed, confirming excellent heat resistance. Further, the contents were visually observed to confirm that the contents were transparent and had no change such as turbidity.
The culture vessel after high-pressure steam sterilization was fixed to a gantry and kept at 25 ° C. for 7 days, but no growth of fungi was observed, indicating that sterilization was performed reliably.

(Culture of Tetrahymena)
Into a newly prepared culture vessel, 4000 ml of distilled water was added and subjected to high-pressure steam sterilization in the same manner as described above. After cooling to room temperature, distilled water was drained from the lower extraction tube 5 to empty the culture vessel. Thereafter, 4000 ml of a culture solution of Tetrahymena (PYD medium: proteose peptone 1%, yeast extract 0.5%, dextrose 0.87%) was put through a feed tube 2 into a sterilized culture vessel. The initial number of viable cells in the culture was measured with a hemocytometer by the Triban Blue dye exclusion test method. The initial number of viable cells in the culture was about 1.2 × 10 ⁴ cells / ml.
After sealing the outlet of the metal cock 6 of the feed tube 2 of the culture container with a rubber stopper, a metal injection needle having a length of 80 cm is inserted from the feed tube 2 through the rubber stopper to the bottom of the culture container, Air that was sterilized through a membrane filter with a pore size of 0.2 μm was supplied at a rate of about 200 cc / min, bubbled from the bottom, and evacuated from the upper exhaust tube 4 through a membrane filter with a pore size of 0.2 μm. For 72 hours. The content solution was sampled and the number of viable cells was counted. As a result, it was confirmed that the contents had grown to about 25 × 10 ⁴ cells / ml, and it was shown that this culture vessel can be used for culturing microorganisms.

[Reference Example 2] Synthesis of block copolymer hydride [P2] As monomers in the polymerization stage, 20.0 parts of styrene, 0.55 parts of n-butyllithium (15% cyclohexane solution), 60.0 parts of isoprene and styrene 96 parts of pellets of block copolymer hydride [P2] were obtained in the same manner as in Reference Example 1 except that 20.0 parts were added to the reaction system in this order for polymerization. The resulting block copolymer hydride had a weight average molecular weight (Mw) of 79,500 and a molecular weight distribution (Mw / Mn) of 1.15. The hydrogenation rate was almost 100%.

[Example 2]
(Extruded film)
Using the block copolymer hydride [P2] pellets obtained in Reference Example 2, a sheet [SP2] having a thickness of 500 μm and a width of 500 mm was formed in the same manner as in Example 1.

(Extruded tube)
Using the block copolymer hydride [P2] pellets obtained in Reference Example 2, a tube [CP2] having an outer diameter of 6 mm and an inner diameter of 4 mm was formed in the same manner as in Example 1.

(injection molding)
Using the block copolymer hydride [P2] pellets obtained in Reference Example 2, a test piece [MP2] having a thickness of 4 mm was molded in the same manner as in Example 1.

(Evaluation of resin for culture vessels)
Using the obtained block copolymer hydride [P2] pellets, extruded sheet [SP2] and test piece [MP2], in the same manner as in Example 1, light transmittance, flexural modulus, tensile strength, tensile elongation And the eluate was evaluated. The light transmittance was 91%, the flexural modulus was 250 MPa, the tensile strength was 41 MPa, and the tensile elongation was 580%. As a result of the eluate test, foaming disappeared within 3 minutes, pH difference was -0.02, ultraviolet absorption was 0.006, and potassium permanganate reducing substance was 0.16 ml. From these results, the block copolymer hydride [P2] is excellent in transparency, has flexibility and sufficient mechanical strength, has low elution properties, and can be adapted as a medical plastic. It was found that the material has excellent characteristics.

(Culture container)
Using the extruded sheet [SP2] and the extruded tube [CP2], the culture container shown in FIG. 1 was prepared in the same manner as in Example 1.

Next, 4000 ml of LB medium was placed in the culture vessel in the same manner as in Example 1. This culture container was excellent in transparency and the contents visibility was good.
Next, this culture vessel was autoclaved in the same manner as in Example 1. The appearance was visually observed, but no deformation or melting was observed, and it was confirmed that the film was excellent in heat resistance. Further, the contents were visually observed to confirm that the contents were transparent and had no change such as turbidity.
The culture vessel after the high-pressure steam sterilization treatment was kept at 25 ° C. for 7 days in the same manner as in Example 1. However, no growth of fungi was observed, and it was found that the sterilization treatment was performed reliably.

(Culture of Tetrahymena)
In the same manner as in Example 1, 4000 ml of the culture solution of Tetrahymena was placed in a newly prepared culture vessel and cultured. It was confirmed that the initial viable cell number in the culture broth was about 1.2 × 10 ⁴ cells / ml and the viable cell number after culture was about 27 × 10 ⁴ cells / ml. It was shown that it can be used for culture.

[Comparative Example 1]
(Extruded film)
Polyethylene (LDPE manufactured by Ube Maruzen Polyethylene Co., Ltd., product name “UBE polyethylene (registered trademark) F023”) was used and heated at 50 ° C. for 4 hours using a hot air dryer in which air was circulated to remove dissolved air. Thereafter, a sheet [CS1] having a thickness of 500 μm and a width of 500 mm was extruded under the same molding conditions as in Example 1.

(injection molding)
Using the same polyethylene, a test piece [CM1] having a thickness of 4 mm was molded in the same manner as in Example 1.

(Evaluation of resin for culture vessels)
Using the obtained polyethylene extruded sheet [CS1] and test piece [CM1], the light transmittance, the flexural modulus, the tensile strength, and the tensile elongation were evaluated in the same manner as in Example 1. The light transmittance was 72%, the flexural modulus was 180 MPa, the tensile strength was 20 MPa, and the tensile elongation was 680%. Extruded sheet [CS1] and test piece [CM1] were placed in a steam sterilizer in the same manner as in Example 1 and subjected to high-pressure steam sterilization at 121 ° C. for 30 minutes.
From these results, polyethylene (LDPE) has sufficient flexibility and mechanical strength, but its transparency is inadequate, the contents visibility is inferior, the heat resistance is low, and high-pressure steam sterilization is impossible. As a resin for use, improvement in physical properties is desired.

[Comparative Example 2]
(Extruded film)
After using polypropylene (made by Nippon Polypro Co., Ltd., product name “NOVATEC (registered trademark) PP FB3HAT”) and heating at 50 ° C. for 4 hours using a hot air dryer in which air was circulated, the dissolved air was removed. A sheet [CS2] having a thickness of 500 μm and a width of 500 mm was extruded under the same molding conditions as in Example 1.

(injection molding)
Using the same polypropylene, a test piece [CM2] having a thickness of 4 mm was molded in the same manner as in Example 1.

(Evaluation of resin for culture vessels)
Using the obtained extruded polypropylene sheet [CS2] and test piece [CM2], evaluation of light transmittance, bending elastic modulus, tensile strength, and tensile elongation was performed in the same manner as in Example 1. The light transmittance was 50%, the flexural modulus was 1700 MPa, the tensile strength was 34 MPa, and the tensile elongation was 110%. When the extruded sheet [CS1] and the test piece [CM1] were put into a steam sterilization apparatus in the same manner as in Example 1 and subjected to a steam sterilization treatment at 121 ° C. for 30 minutes, the deformation was small and heat resistance was obtained. Was.
From these results, polypropylene has high heat resistance and can be sterilized by steam, but the transparency is poor, the contents visibility is remarkably inferior, and the flexibility is insufficient. Improvement is desired.

[Reference Example 3] Synthesis of block copolymer hydride [P3] As monomers in the polymerization stage, 32.5 parts of styrene, 0.68 parts of n-butyllithium (15% cyclohexane solution), 35.0 parts of isoprene and styrene 94 parts of block copolymer hydride [P3] pellets were obtained in the same manner as in Reference Example 1 except that 32.5 parts were added to the reaction system in this order for polymerization. The resulting block copolymer hydride had a weight average molecular weight (Mw) of 65,500 and a molecular weight distribution (Mw / Mn) of 1.10. The hydrogenation rate was almost 100%.

[Comparative Example 3]
(Extruded film)
Using the block copolymer hydride [P3] pellets obtained in Reference Example 3, a sheet [SP3] having a thickness of 500 μm and a width of 500 mm was formed in the same manner as in Example 1.

(injection molding)
Using the block copolymer hydride [P3] pellets obtained in Reference Example 3, a test piece [MP3] having a thickness of 4 mm was molded in the same manner as in Example 1.

(Evaluation of resin for culture vessels)
Using the extruded sheet [SP3] and the test piece [MP3] of the obtained block copolymer hydride, the light transmittance, the flexural modulus, the tensile strength, and the tensile elongation were evaluated in the same manner as in Example 1. . The light transmittance was 91%, the flexural modulus was 2100 MPa, the tensile strength was 11 MPa, and the tensile elongation was 4%. When the extruded sheet [SP3] and the test piece [MP3] were put into a steam sterilizer in the same manner as in Example 1 and subjected to a steam sterilization treatment at 121 ° C. for 30 minutes, the deformation was small and heat resistance was obtained. Was.
From these results, the block copolymer hydride containing a large amount of styrene component has high transparency and excellent contents visibility, heat resistance and steam sterilization, but it is low in flexibility and cracks when bent. It is unsuitable as a resin for culture vessels.

  The culture vessel formed from the specific block copolymer hydride of the present invention is excellent in transparency, flexibility, heat resistance and low elution, has good content visibility, and has an electron beam and γ In addition to sterilization by wire, steam sterilization treatment is also possible, and it is a culture container suitable for culturing microorganisms, animal and plant tissues, and is useful as a disposable bioreactor.

1: Cultivation container body 2: Feeding tube 3: Sampling tube 4: Exhaust tube 5: Extraction tube 6: Metal cock connected to each tube end

Claims (1)

At least two polymer blocks [A] mainly composed of repeating units derived from an aromatic vinyl compound, and at least one polymer block [B] mainly composed of repeating units derived from a chain conjugated diene compound. When the weight fraction of the entire polymer block [A] in the entire block copolymer is wA, and the weight fraction of the entire polymer block [B] in the entire block copolymer is wB, wA And a block copolymer having a ratio of wB (wA: wB) of 30:70 to 60:40 formed from a hydride of a block copolymer obtained by hydrogenating 90% or more of all unsaturated bonds. Container.

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