JPH08289918A - Seal material for medicine and medical care - Google Patents

Abstract

PURPOSE: To provide a seal material for medicine and medical care, which is a high strength rubber plug or the like for preventing the content from the pollution by the rubber piece. CONSTITUTION: A seal material for medicine and medical care is obtained by curing a curable composition containing saturated hydrocarbon polymer having alkenyl group and hydrosilyl compound. This seal material for medicine and medical care prevents the content from the pollution by robber pieces, provides excellent gas permeability resistance, safety and easy production since a vulcanizing agent is not used.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a novel pharmaceutical / medical sealing material using a saturated hydrocarbon polymer which can be crosslinked by a hydrosilylation reaction.

[0002]

2. Description of the Related Art Conventionally, saturated hydrocarbon rubber polymers represented by butyl rubber have excellent gas permeation resistance, and therefore medical and medical seals such as medical rubber stoppers, syringe gaskets and vacuum blood collection rubber stoppers. It has been used as a material. In addition to gas permeation resistance, these sealing materials are cross-linked in order to satisfy various characteristics such as chemical resistance, non-elution resistance, sterilization resistance, needle stick resistance, and self-sealing property, and in addition to being shaped. It is common.

Since such a sealing material is usually crosslinked by vulcanization, additives such as a vulcanization accelerator and a vulcanization activator are required. However, there is a problem that these are eluted during sterilization, or sulfurous acid gas is generated when incinerating used products, and improvement is required. Further, in terms of productivity, there are problems that large-scale equipment and complicated processes are required, and productivity is poor.

Therefore, the use of a thermoplastic elastomer which can be injection-molded in a short time by a thermoplastic processing machine without vulcanization molding is proposed in Japanese Patent Laid-Open No. 58-58057. Specifically, it is a stopper for a medical container made of a polymer mixture of butyl rubber and a thermoplastic elastomer,
This rubber product lacks toughness, and rubber pieces and fine particles fall and mix with the contents in the container when the rubber stopper is plugged into the mouth of the medical container or when the injection needle is pierced into the rubber stopper. was there.

In order to improve this drawback, use of a dynamically crosslinked thermoplastic elastomer in which butyl rubbers almost completely crosslinked in crystalline polypropylene are dispersed in JP-A-6-237972 and JP-A-6-245977. Is proposed. This rubber stopper is an injection-moldable material having low needle puncture resistance, no problem in resealing property after puncture, good gas barrier property, tough mechanical properties and excellent rubber elasticity. However, this material requires heating to 180 to 220 ° C. when melting polypropylene and the like, and addition of a vulcanization accelerator and the like for crosslinking.

[0006]

The object of the present invention is to apply a novel crosslinking method which does not require vulcanization,
Another object of the present invention is to provide a medical / medical sealing material that can be molded using an injection molding machine or the like and that can be molded at a relatively low temperature and has heat resistance and the like that cannot be achieved by a thermoplastic elastomer.

[0007]

That is, the present invention relates to a medical / medical sealing material obtained by curing a curable composition containing the following components (A), (B) and (C) as essential components. Is. (A) Saturated hydrocarbon rubber polymer containing at least one alkenyl group in the molecule, (B) Curing agent containing at least two hydrosilyl groups in the molecule, (C) Hydrosilylation catalyst.

The component (A) used in the present invention is a saturated hydrocarbon rubber polymer having at least one alkenyl group in the molecule. Here, the saturated hydrocarbon rubber-based polymer is a concept that means a rubber-based polymer that does not substantially contain a carbon-carbon unsaturated bond other than an aromatic ring, and constitutes the main chain excluding the alkenyl group. It means that the repeating unit is composed of a saturated hydrocarbon. Further, the alkenyl group refers to a group having one carbon-carbon double bond. In the present invention, the component (A) contains 1 to 1 alkenyl groups in one molecule.
It is desirable to have ten, preferably two to five. The polymer forming the skeleton of the saturated hydrocarbon rubber-based polymer which is the component (A) is obtained by polymerizing (1) an olefin compound having 1 to 6 carbon atoms such as ethylene, propylene, 1-butene and isobutylene as a main monomer. It can be obtained by a method such as (2) homopolymerization of a diene compound such as butadiene or isoprene, or copolymerization of the above olefin compound and a diene compound, followed by hydrogenation. In terms of easy introduction of a functional group at the terminal, easy control of molecular weight, and increase in the number of terminal functional groups, isobutylene-based polymer, hydrogenated polybutadiene-based polymer or hydrogenated polyisoprene-based polymer Is desirable.

In the isobutylene-based polymer, all of the monomer units may be formed from isobutylene units, and the monomer unit having copolymerizability with isobutylene is preferably contained in the isobutylene-based polymer in an amount of 50% ( % By weight, the same below), more preferably 30% or less, particularly preferably 10% or less. Examples of such a monomer component include olefins having 4 to 12 carbon atoms,
Examples thereof include vinyl ether, aromatic vinyl compounds, vinylsilanes, allylsilanes and the like. Specific examples of such a copolymer component include, for example, 1-butene, 2-butene, 2-methyl-1-butene, 3-methyl-1-butene, pentene, 4-methyl-1-pentene, hexene,
Vinyl cyclohexane, methyl vinyl ether, ethyl vinyl ether, isobutyl vinyl ether, styrene, α-methyl styrene, dimethyl styrene, pt-
Butoxystyrene, p-hexenyloxystyrene, p
-Allyloxystyrene, p-hydroxystyrene, β-
Pinene, indene, vinyldimethylmethoxysilane, vinyltrimethylsilane, divinyldimethoxysilane, divinyldimethylsilane, 1,3-divinyl-1,1,
3,3-tetramethyldisiloxane, trivinylmethylsilane, tetravinylsilane, allyldimethylmethoxysilane, allyltrimethylsilane, diallyldimethoxysilane, diallyldimethylsilane, γ-methacryloyloxypropyltrimethoxysilane, γ-methacryloyloxypropylmethyldimethoxy Examples include silane.

In the hydrogenated polybutadiene-based polymer and other saturated hydrocarbon-based polymers as well as in the case of the isobutylene-based polymer, in addition to the monomer unit as the main component,
Other monomer units may be contained. Further, in the saturated hydrocarbon rubber-based polymer used as the component (A) in the present invention, butadiene, isoprene, 1,13-tetradecadiene, 1,9-decadiene, and 1 are included in the range in which the object of the present invention is achieved. A small amount of a monomer unit such as a polyene compound such as 5,5-hexadiene that leaves a double bond after polymerization,
Preferably, it may be contained in the range of 10% or less.

The number average molecular weight (GPC method, polystyrene conversion) of the saturated hydrocarbon rubber polymer is 500 to 100.
It is preferably about 000, and particularly 1000 to 400
A liquid material having a liquidity of about 00 and a material having fluidity are preferable from the viewpoint of easy handling. Regarding the method of introducing the alkenyl group into the saturated hydrocarbon rubber-based polymer of the component (A), various proposals can be made. However, the method of introducing the alkenyl group after the polymerization and the method of introducing the alkenyl group during the polymerization The methods of introduction can be broadly divided.

Examples of the method of introducing an alkenyl group after polymerization include those described in JP-A No. 64-11102. For example, in the case of a polymer having a hydroxyl group at the terminal, the main chain, or the side chain, the hydroxyl group is -ONa or -O.
General formula (1) CH ₂ ═CH—R ¹ —Y (1) (wherein Y is a halogen atom such as chlorine atom or iodine atom, R ¹ is —R ² —, —R ^2- OC (= O)-or
—R ² —C (═O) — (R ² is a divalent hydrocarbon group having 1 to 20 carbon atoms, and a preferred specific example is an alkylene group,
And a divalent organic group represented by a cycloalkylene group, an arylene group and an aralkylene group.

[0013]

Embedded image A divalent group selected from the above is particularly preferable. By reacting the organic halogen compound represented by the formula (1), a saturated hydrocarbon rubber-based polymer having a terminal alkenyl group is produced. As a method of converting the terminal hydroxyl group of the terminal hydroxy-saturated hydrocarbon rubber-based polymer into an oxymetal group, alkali metals such as Na and K; metal hydrides such as NaH; N
A metal alkoxide such as aOCH ₃ ; a method of reacting with caustic soda, caustic alkali such as caustic potash, and the like.

According to the above-mentioned method, a terminal alkenyl group-containing saturated hydrocarbon rubber-based polymer having almost the same molecular weight as the terminal hydroxy-saturated hydrocarbon rubber-based polymer used as a starting material can be obtained, but a higher molecular weight polymer is obtained. If desired, obtain two halogen atoms in one molecule such as methylene chloride, bis (chloromethyl) benzene, bis (chloromethyl) ether before reacting with the organohalogen compound of the general formula (1). The molecular weight can be increased by reacting it with a polyvalent organic halogen compound containing the above, and then by reacting with the organic halogen compound represented by the general formula (1), it has a higher molecular weight and has an alkenyl group at the terminal. A saturated hydrocarbon rubber polymer can be obtained.

Specific examples of the organic halogen compound represented by the general formula (1) include allyl chloride, allyl bromide, vinyl (chloromethyl) benzene, allyl (chloromethyl) benzene, allyl (bromomethyl) benzene, allyl ( Chloromethyl) ether, allyl (chloromethoxy) benzene, 1-hexenyl (chloromethoxy) benzene, allyloxy (chloromethyl)
Examples thereof include, but are not limited to, benzene and the like. Of these, allyl chloride is preferable because it is inexpensive and easily reacts.

Further, there is a method of introducing an alkenyl group into a polymer having a halogen atom such as an isobutylene polymer having a covalently bound chlorine atom. JP-A-63-105
Methods described in Japanese Patent Application Laid-Open No. 005, 005, Japanese Patent Application Laid-Open No. 4-154815 and the like can be mentioned. For example, a method of performing a Friedel-Crafts reaction using various alkenylphenyl ethers, a method of reacting allyltrimethylsilane or the like in the presence of a Lewis acid to carry out a substitution reaction between a chlorine atom and an allyl group, and various phenols. Examples of the method include a Friedel-Crafts reaction using a group to introduce a hydroxyl group into the polymer, and then using the above alkenyl group-introducing method in combination.

As a method of introducing an alkenyl group during polymerization, for example, a compound having a halogen atom as an initiator and a chain transfer agent, and a carbon atom to which the halogen atom is bonded is bonded to an aromatic ring carbon And / or a cationic polymerizable monomer containing a halogen atom, wherein the carbon atom to which the halogen atom is bonded is a tertiary carbon atom, and an isobutylene-containing monomer is used with a Lewis acid as a catalyst. In the cationic polymerization, a method for producing an isobutylene-based polymer having an allyl terminal by adding allyltrimethylsilane to the polymerization system can be mentioned. Further, an isobutylene system having an alkenyl group at the end of a main chain or a side chain by adding a non-conjugated diene such as 1,9-decadiene or an alkenyloxystyrene such as p-hexenyloxystyrene to a polymerization system. A method for producing a polymer may be mentioned (JP-A-4-28830).
99 publication).

The composition used as the cationic polymerization catalyst is
The Lewis acid which is a component is MX'n (M is a metal atom, X'is
Halogen atom, n is a positive integer), for example
BCl₃, Et₂AlCl, EtAlCl₂, AlCl
₃, SnCl_Four, TiCl _Four, VCl_Five, FeCl₃,
 BF₃But not limited to
is not. Of these Lewis acids, BCl₃, SnC
l_Four, BF₃And the like, and more preferable ones
TiCl_FourIs mentioned. The amount of Lewis acid used starts
0.1 to 10 times the molar number of the agent and chain transfer agent is preferable.
More preferably 2 to 5 times.

The curing agent which is the component (B) of the present invention is not limited as long as it has at least two hydrosilyl groups in the molecule. Here, the hydrosilyl group refers to a SiH group. When two hydrogen atoms are bonded to the same Si atom, the number of hydrosilyl groups is calculated to be two. As the component (B), polyorganohydrogen siloxane is mentioned as one of the preferable ones, and its structure will be specifically described as follows.

[0020]

Embedded image Examples thereof include chain-like and cyclic ones. Also,
As the component (B), an organic curing agent containing at least two polyorganohydrogensiloxane residues in the molecule is also preferable. Preferred examples of the organic curing agent include organic curing agents represented by the following formula (2).

R ⁴ Xa (2) (X is a polyorganohydrogensiloxane residue containing at least one hydrosilyl group, and R ⁴ is 2 to 2 carbon atoms.
2000 1 to 4 valent hydrocarbon groups. a is an integer selected from 2 to 4. ) In formula (2), X represents a polyorganohydrogensiloxane residue containing at least one hydrosilyl group.

[0022]

Embedded image Examples thereof include chain-like and cyclic ones. Among the various hydrosilyl group-containing groups described above, the following are particularly preferable in that the hydrosilyl group-containing curing agent which is the component (B) of the present invention has good compatibility with various organic polymers such as the component (A). .

[0023]

[Chemical 4] In the formula (2), R ⁴ is 1 to 4 having 2 to 2000 carbon atoms.
It is a valent hydrocarbon group, and in view of compatibility with various organic polymers and reactivity of the hydrosilyl group, a saturated hydrocarbon group is particularly preferable. Further, as the component (B), an organic curing agent having no polyorganohydrogensiloxane residue can also be used. A preferred example of such an organic curing agent is represented by the following formula (3).

R ⁵ Xb (3) (X is a group containing at least one hydrosilyl group other than the polyorganohydrogensiloxane residue, R ⁵ is a monovalent to tetravalent hydrocarbon group having 2 to 2000 carbon atoms, b is 1
In integer) formula selected from 4 (3), Specific examples of a _{X, -Si (H) n (} CH 3) 3-n, -Si (H) n (C 2 H
_{5) 3-n, -Si (} H) n (C 6 H 5) 3-n, (n = 1
A group containing only one silicon atom such as —SiH ₂ (C ₆ H ₁₃ ),

[0025]

Embedded image And a group containing two or more silicon atoms. In the formula (3), R ⁵ is a monovalent to tetravalent hydrocarbon group having 2 to 2000 carbon atoms, which is less likely to impair the compatibility with various organic polymers, and the reactivity of the hydrosilyl group is also taken into consideration. If so, a saturated hydrocarbon group or the like is particularly preferable.

The number of hydrosilyl groups contained in the formulas (2) and (3) may be at least two in one molecule, but is preferably 2 to 15 and particularly preferably 3 to 12. When the composition of the present invention is cured by a hydrosilylation reaction, if the number of the hydrosilyl groups is less than 2, the curing is slow and a curing failure often occurs. Also,
When the number of the hydrosilyl groups exceeds 15, (B)
The curing agent as a component may have poor stability, and a large amount of hydrosilyl groups may remain in the cured product even after curing, causing voids and cracks. The molecular weight of the component (B) is preferably 30,000 or less. As a method for producing the hydrosilyl group-containing hydrocarbon-based curing agent that is the component (B) of the present invention, any method may be used. For example, a hydrocarbon-based curing agent having a Si-Cl group in the molecule is LiAlH.
₄ , SB in the curing agent after being treated with a reducing agent such as NaBH ₄
A method of reducing an i-Cl group to a Si-H group, an organic compound such as a hydrocarbon compound having a functional group X in the molecule, and a functional group Y and a hydrosilyl group which react with the functional group X in the molecule at the same time. With a compound having a hydrosilyl group in the molecule after the reaction by selectively hydrosilylating a polyhydrosilane compound having at least two hydrosilyl groups with respect to an organic compound such as a hydrocarbon compound containing an alkenyl group. A method for obtaining the remaining product is exemplified.

Of the above-mentioned methods, the method can be preferably used because the manufacturing process is generally simple. In this case, two or more hydrosilyl groups of some polyhydrosilane compounds may react with an alkenyl group in an organic compound such as a hydrocarbon compound to increase the molecular weight. It can be used as an ingredient without any problem.

The molar ratio of the hydrosilyl group and the alkenyl group of the components (A) and (B) produced as described above is preferably 0.2 to 5.0, more preferably 0.4 to 2.
5 is particularly preferred. When the molar ratio is less than 0.2,
When the composition of the present invention is cured, only a cured product with insufficient tackiness and low tackiness is obtained, and when the molar ratio is more than 5.0, the hydrosilyl group active in the cured product after curing is also obtained. Since a large amount remains, cracks and voids tend to occur, and a uniform and strong cured product tends not to be obtained.

As the hydrosilylation catalyst which is the component (C) of the present invention, any catalyst can be used. Specifically, chloroplatinic acid, platinum simple substance, solid platinum supported on a carrier such as alumina / silica / carbon black, a platinum-vinylsiloxane complex such as Pt (ViMe ₂ SiOSiMe ₂ Vi) ) N Pt [(MeViSiO) ₄ ] m, platinum-phosphine complex such as Pt (PPh ₃ ) ₄ Pt (PBu ₃ ) ₄ , platinum-phosphite complex such as Pt [P (OPh) ₃ ] ₄ Pt [P (OBu ) ₃ ] ₄ (in the formula, Me is a methyl group, Bu is a butyl group, Vi is a vinyl group, Ph is a phenyl group, and n and m are integers) and Pt (acac) ₂ . Also, Ashby U.S. Pat. Nos. 3,159,601 and 3
Also included are the platinum-hydrocarbon composites described in 159662, as well as the platinum alcoholate catalysts described in Lamoreaux US Pat. No. 3,209,972.

As an example of a catalyst other than the platinum compound,
Is RhCl (PPh₃)₃, RhCl₃, Rh / Al
₂O₃, RuCl₃, IrCl₃, FeCl₃, AlC
l₃, PdCl₂・ 2H₂O, NiCl₂, TiC
l_Four, And the like. These catalysts used alone
It is also possible to use two or more kinds in combination. In terms of catalytic activity
Chloroplatinic acid, platinum-olefin complex, platinum-vinyl chloride
Roxane complex, Pt (acac)₂Etc. are preferred. catalyst
The amount is not particularly limited, but the alkene in the component (A) is
10 for 1 mol of ru radical^-1-10 ^-8for the range of mol
It is good to be there. Preferably 10^-2-10^-6range of mol
Good to use in. Further, the hydrosilylation catalyst is generally
It is very expensive and corrosive, and also generates a large amount of hydrogen gas.
As the cured product may foam, 10^-1Less than a mole
It is better not to use it.

In the present invention, since the curable composition is cured by the addition reaction of the Si-H group to the alkenyl group using the hydrosilylation catalyst, the curing rate is very fast, which is convenient for line production. . In addition, a storage stability improver may be added for use as a one-pack composition in terms of simplification of the process. The storage stability improver may be an ordinary stabilizer known as a storage stabilizer for the hydrosilyl group-containing curing agent which is the component (B),
It is not particularly limited. Specifically, a compound containing an aliphatic unsaturated bond, an organic phosphorus compound, an organic sulfur compound, a nitrogen-containing compound, a tin compound, an organic peroxide and the like can be preferably used. More specifically, 2-
Benzothiazolyl sulfide, benzothiazole, thiazole, dimethyl acetylene dicarboxylate, diethyl acetylene dicarboxylate, BHT, butylhydroxyanisole, vitamin E, 2- (4-morphogenyldithio) ) Benzothiazole, 3-methyl-1
-Butene-3-ol, acetylenically unsaturated group-containing organosiloxane, acetylene alcohol, 3-methyl-
1-butyl-3-ol, diallyl fumarate, diallyl maleate, diethyl fumarate, diethyl maleate
G, dimethyl maleate, 2-pentene nitrile, 2,
3-dichloropropene and the like are mentioned, and thiazole and benzothiazole are particularly preferable from the viewpoint of compatibility of pot life / rapid curing property. The amount of storage stability improver used is (A)
It is preferable to use it in the range of 10 ⁻⁶ to 10 ⁻¹ mol with respect to ¹ mol of the Si—H group-containing compound of the component and the component (B). If it is less than 10 ⁻⁶ , the storage stability of the component (B) will not be sufficiently improved, and if it exceeds 10 ⁻¹ mol, curing may be hindered. The storage stability improvers may be used alone or in combination of two or more.

In addition to the above-mentioned essential components, the curable composition of the present invention may contain a reinforcing agent, a filler, an antioxidant, an ultraviolet absorber, if necessary, in addition to the above-mentioned essential components.
A pigment, a surfactant and the like can be added appropriately. Among these, specific examples of the reinforcing agent and the filler include calcium carbonate, clay, talc, titanium oxide, zinc white, diatomaceous earth, barium sulfate, fine silica powder, carbon black and the like.

Further, a plasticizer for adjusting the flow characteristics and facilitating molding such as injection molding may be added. The plasticizer is added to improve the fluidity of the composition, and a generally used plasticizer can be used, but it is compatible with the saturated hydrocarbon polymer used in the present invention. A good one is preferable. Specific examples of the plasticizer include, for example, polybutene, hydrogenated polybutene, α-methylstyrene oligomer, liquid polybutadiene, hydrogenated liquid polybutadiene, paraffin oil, naphthene oil, atactic polypropylene and the like, but among them, preferred Hydrocarbon compounds such as hydrogenated polybutene, hydrogenated liquid polybutadiene, paraffin oil, naphthene oil and atactic polypropylene which do not contain a saturated bond are preferable.

The curable composition of the present invention does not require vulcanization despite being crosslinked and can be molded by using an injection molding machine or the like, and can be molded at a relatively low temperature, and has flexibility and gas permeation resistance. Provided is a pharmaceutical / medical sealing material which has satisfactory toughness, heat resistance, and the like, which are not satisfied by a thermoplastic elastomer, while satisfying the requirements of antibacterial property, sterilization resistance, and non-elution property. Hereinafter, the present invention will be described in more detail with reference to Examples. Production Example 1 A 1 L pressure-resistant glass autoclave was equipped with a stirring blade, a three-way cock, and a vacuum line, and the polymerization container was dried by heating at 100 ° C. for 1 hour while pulling a vacuum in the vacuum line, and then cooled to room temperature. The pressure was returned to normal pressure with nitrogen using a cock.

Then, while flowing nitrogen from one of the three-way cocks, a molecular syringe was put into the autoclave using a syringe.
Solvent dried by sieve treatment, methylene chloride 15
5 mL and n-hexane 348 mL were introduced. Then D
10 in which 7.5 mmol of CC (compound A below) was dissolved
mL of methylene chloride solution was added. Then, 3.0 mmol of the additive α-picoline was added.

Next, the isobutylene dehydrated by passing through a column packed with barium oxide was 112.8.
After connecting the pressure-resistant glass liquefied gas sampling tube with a needle valve containing g to a three-way cock, the container body was immersed in a dry ice-acetone bath at -70 ° C, and the inside of the polymerization vessel was cooled for 1 hour while stirring. . After cooling, after decompressing the inside with a vacuum line, the needle valve was opened and isobutylene was introduced into the polymerization vessel from the pressure-resistant glass liquefied gas sampling tube. After that, the pressure was returned to normal pressure by flowing nitrogen from one of the three-way cocks, cooling was further continued for 1 hour under stirring, and the inside of the polymerization vessel was maintained at -70 ° C.

Next, 7.1 g of TiCl ₄ (37.5 mm)
ol) was added from a three-way cock using a syringe to start polymerization, and 1 hour later, 20.8 g (150 mmol) of 1,9-decadiene was added. After reacting for a further 8 hours, the catalyst was deactivated by pouring the reaction mixture into water. Next, the organic layer was washed three times with pure water and then separated, and methylene chloride, n-hexane, and 1,
By distilling off 9-decadiene under reduced pressure, an allyl-terminated isobutylene polymer was obtained.

The structure of Compound A is as shown below.

[0039]

[Chemical 6] Production Example 2 A 1 L pressure-resistant glass autoclave was equipped with a stirring blade, a three-way cock and a vacuum line, and the polymerization container was dried by heating at 100 ° C. for 1 hour while drawing a vacuum in the vacuum line, and then cooled to room temperature and then three-way. The pressure was returned to normal pressure with nitrogen using a cock.

Then, while flowing nitrogen from one of the three-way cocks, the molecular weight was adjusted to the autoclave using a syringe.
Solvent dried by sieve treatment, methylene chloride 20
4 mL and n-hexane 336 mL were introduced. Then D
10 mL of methylene chloride solution containing 5.0 mmol of CC was added. Further subsequently, 1.0 mmol of the additive α-picoline was added.

Next, 37.5 g of isobutylene dehydrated by passing through a column filled with barium oxide was used.
After the pressure-resistant glass liquefied gas sampling tube with a needle valve was connected to a three-way cock, the container body was immersed in a dry ice-acetone bath at -70 ° C, and the inside of the polymerization vessel was cooled for 1 hour while stirring. After cooling, after decompressing the inside with a vacuum line, the needle valve was opened and isobutylene was introduced into the polymerization vessel from the pressure-resistant glass liquefied gas sampling tube. After that, the pressure was returned to normal pressure by flowing nitrogen from one of the three-way cocks, cooling was further continued for 1 hour under stirring, and the inside of the polymerization vessel was maintained at -70 ° C.

Next, 13.7 g (72.0 m) of TiCl _{4 was used.}
(mol) was added from a three-way cock with a syringe to start polymerization, and 1 hour later, 19.9 g (144 mmol) of 1,9-decadiene was added. 6 more
After reacting for a period of time, the catalyst was deactivated by pouring the reaction mixture into water. Next, the organic layer was washed with pure water three times and then separated, and methylene chloride, n-hexane, and 1,9-decadiene were distilled off under reduced pressure to obtain an allyl-terminated isobutylene polymer. Production Example 3 A 3 L pressure-resistant glass autoclave was equipped with a stirring blade, a three-way cock and a vacuum line, and the polymerization container was dried by heating at 100 ° C. for 1 hour while pulling a vacuum in the vacuum line to room temperature. After cooling to normal pressure, the pressure was returned to normal pressure with nitrogen using a three-way cock.

Thereafter, while flowing nitrogen from one of the three-way cocks, methylene chloride 61, a solvent dried by molecular sieve treatment on the autoclave using a syringe, was used.
8 mL and 1001 mL of n-hexane were introduced. Then 50 mL of methylene chloride solution in which 15 mmol of DCC was dissolved was added. Further subsequently, 6.0 mmol of the additive α-picoline was added.

Next, a pressure-resistant glass liquefied gas sampling pipe with a needle valve containing 224 g of isobutylene dehydrated by passing through a column filled with barium oxide was connected to a three-way cock, and then the container body was placed at -70 ° C. Was immersed in a dry ice-acetone bath, and the inside of the polymerization vessel was cooled for 1 hour while stirring. After cooling, after decompressing the inside with a vacuum line, the needle valve was opened and isobutylene was introduced into the polymerization vessel from the pressure-resistant glass liquefied gas sampling tube.
After that, the pressure was returned to normal pressure by flowing nitrogen from one of the three-way cocks, cooling was further continued for 1 hour under stirring, and the inside of the polymerization vessel was maintained at -70 ° C.

Next, 14.2 g (75 mmo) of TiCl _{4 was} used.
1) was added from a three-way cock using a syringe to start polymerization, and after 1 hour, allylsilane 10.3 was added.
g (90 mmol) was added. After reacting for an additional 1 hour, the reaction mixture was poured into methanol to stop the reaction. After stirring for a while, the mixture was allowed to stand and the polymer was precipitated and separated.

The polymer obtained in this way is re-n
-Dissolved in hexane and washed with pure water three times, the solvent was distilled off to obtain an allyl-terminated isobutylene-based polymer. The yield was calculated from the yields of the polymers obtained in Production Examples 1, 2, and 3, and Mn and Mw / Mn were measured by the GPC method.
Further, the terminal structure was subjected to 300 MHz ¹ H-NMR analysis to determine the protons (protons derived from the initiator: 6.
It was determined by measuring and comparing the resonance signal intensities of 5 to 7.5 ppm, and vinyl protons derived from the polymer end: 4.5 to 5.9 ppm). The results are shown in Table 1.

[0047]

[Table 1] Production Example 4 To 300 g of hydrogenated polyisoprene having hydroxyl groups at both ends (trade name: Epoll, manufactured by Idemitsu Petrochemical Co., Ltd.), 50 mL of toluene was added and dehydrated by azeotropic degassing. t-BuO
What melt | dissolved K48g in THF200mL was inject | poured. After reacting for 1 hour at 50 ° C., allyl chloride 4
7 mL was added dropwise over about 30 minutes. 50 ℃ after dropping
The reaction was continued for another hour. After completion of the reaction, 30 g of aluminum silicate was added to the reaction solution to adsorb the generated salt
Was added and stirred at room temperature for 30 minutes. About 2 by filtration and purification
50 g of allyl-terminated hydrogenated polyisoprene was obtained as a viscous liquid. It was confirmed by 300 MHz ¹ H-NMR analysis that an allyl group was introduced into 92% of the ends.
The viscosity measured by E-type viscometer is 302 poise (23 ° C).
Met.

* Representative physical properties of Epoll (from technical data) Hydroxyl group content (meq / g) 0.90 Viscosity (poise / 30 ° C) 700 Average molecular weight (VPO measurement) 2500 Production example 5 Stirrable 2 L 1,3,5,7 in the glass reactor of
-500 g of tetramethylcyclotetrasiloxane (2.
08 mol), 600 g of toluene, bis (1,3-divinyl-1,1,3,3-tetramethyldisiloxane) platinum complex catalyst (8.0 × 10 −7 mol) were added, and the mixture was placed under nitrogen 8
Heated to 0 ° C. 28.7 g (0.208 mol) of 1,9-decadiene and 58 of toluene with sufficient stirring.
g mixture was added over 1 hour. After the total amount was added, the residual amount of 1,9-decadiene was quantified by gas chromatography, and stirring was continued at 80 ° C. until it disappeared. The reaction mixture was concentrated to obtain 110 g of Si-H group-containing curing agent as a residue. This product was found by GPC analysis to be compound B having the structure of the following formula as the main product. Further, the above-mentioned various analyzes revealed that the Si-H group content of this product was 0.967 mol / 100 g.

[0049]

[Chemical 7] Examples 1 to 4 and Comparative Example Compound (B) which is the component (A) obtained in Production Examples 1 and 2 and component (B) obtained in Production Example 5 or compound C which is the component (B) having the structure shown below. ,

[0050]

Embedded image Further, fine silica powder (manufactured by Nippon Aerosil Co., Ltd.), and bis (1,3-divinyl-1,1,3,3-) as a catalyst.
Tetramethyldisiloxane) platinum complex catalyst (8.3 × 1
0-5 mmol / μl, xylene solution), storage stability improver (dimethyl maleate), and plasticizer (paraffinic process oil) were weighed as shown in Table 2 and mixed to prepare a sample.

[0051]

[Table 2] An injection molding machine (M-32 type) manufactured by Meiki Seisakusho was used for each of the above-mentioned samples, and a JIS K6301 dumbbell No. 3 type mold was used. The rotation speed of the screw was 50 rpm, and the temperature was controlled at 23 to 30 ° C. The mold temperature was 120 ° C. and a molded product was obtained in a hold for 10 minutes. Dumbbell tensile properties of the obtained molding (measured by JI
According to SK6301), the hardness was measured. Table 3 shows the results.

[0052]

[Table 3] As is clear from Table 3, these molded products have sufficient strength, and when used as a rubber stopper, the rubber piece does not drop when the stopper is plugged or the injection needle is punctured. Example 5 A cured product obtained by curing the curable composition of Example 1 is JIS
According to Z0208, the moisture permeability was measured, and the cured product was treated with J
The transmission coefficient was measured according to IS Z1707. Moreover, in order to evaluate the heat resistance, the same cured product was treated at 150 ° C. for 15
It was kept for 00 hours or more, and the presence or absence of surface melting was observed. The results are shown in Table 4.

Example 6 Evaluations were made in the same manner as in Example 5 except that the curable composition of Example 2 was used. The results are shown in Table 4.

[0054]

[Table 4] As shown in Table 4, it can be confirmed that this cured product is excellent in low gas / water vapor permeability and further excellent in heat resistance by using the saturated hydrocarbon rubber polymer.

[0055]

EFFECTS OF THE INVENTION The curable composition of the present invention is excellent in productivity such that it can be molded at a relatively low temperature using an injection molding machine. Further, since it also has strong mechanical properties, rubber pieces and fine particles do not drop when the injection needle is punctured. Further, it is a medical / medical sealing material having excellent gas permeation resistance and also having heat resistance and the like which cannot be achieved by a thermoplastic elastomer. Further, the curable composition of the present invention utilizes a hydrosilylation reaction for cross-linking, and since a vulcanizing agent or the like is not added, it is very safe as compared with a vulcanized rubber which is also excellent in heat resistance. It is expensive.

Claims (4)

[Claims] 1. A medical / medical sealing material obtained by curing a curable composition containing the following components (A), (B) and (C) as essential components; (A) at least one in a molecule A saturated hydrocarbon rubber-based polymer containing an alkenyl group, (B) a curing agent containing at least two hydrosilyl groups in the molecule, and (C) a hydrosilylation catalyst. 2. The pharmaceutical / medical seal material according to claim 1, wherein the polymer as the component (A) is a polymer having a total amount of repeating units derived from isobutylene of 50% by weight or more. 3. The pharmaceutical / medical sealing material according to claim 1, wherein the curing agent as the component (B) is a polyorganohydrogensiloxane containing at least two hydrosilyl groups in the molecule. 4. The medical / medical sealing material according to claim 1, wherein the curing agent as the component (B) is an organic compound containing a polyorganohydrogensiloxane residue having at least one hydrosilyl group.