JPS639982B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Application Field] The present invention relates to a composite molded product of a vinyl chloride resin composition and an addition polymerizable silicone rubber. [Prior art] Vinyl chloride resins are made flexible by adding plasticizers or polymeric elastomers, and have excellent transparency, adhesive properties, and high-frequency processability, making them suitable for medical devices, food packaging, etc. It has been widely used. However, in the field of medical devices, vinyl chloride resin products have poor antithrombotic properties and tissue compatibility, which causes various problems when used in direct contact with blood or used in the body for long periods of time. On the other hand, although silicone is expected to be used as a medical material due to its excellent antithrombotic properties and tissue compatibility, its usage is still limited due to its high price and low mechanical strength. In order to compensate for the advantages and disadvantages of both, many attempts have been made to compound vinyl chloride resins by kneading silicone oil or coating them. However, with soft vinyl chloride resins, it has generally been thought that it is difficult to firmly integrate them with silicone due to the influence of additives such as plasticizers. In order to overcome this problem, various methods have been proposed, such as applying a primer treatment to the surface of a soft vinyl chloride resin and then forming a silicone layer, but the process is complicated and many primers use ethyl acetate. Since solvents such as , toluene, etc. are used, there is concern that they may remain, and even if they are once bonded, they may peel off over time. On the other hand, according to JP-A No. 54-156083, etc., there is a method in which the surface of a vinyl chloride resin is treated with low-temperature plasma in advance, and then a cured layer of a condensation type room-temperature curing silicone rubber is formed. 58−
According to Publication No. 32773, a hardened layer is formed in advance on the surface of a vinyl chloride resin material by plasma treatment, etc., and then a silicone resin layer made of dimethylpolysiloxane or dimethylpolysiloxane modified with an alkyl group is formed and improved. It is proposed that. [Purpose of the invention] It is clear that silicone resin can be fixed by these methods, but plasma treatment is difficult to completely treat the inside of a tube with a narrow diameter or a long tube-like object and form a hardened layer. It is. The present inventors have developed an anti-thrombotic method directly applied to the surface of a soft vinyl chloride resin molded product, which has been considered difficult in the past, without forming a hardened layer such as plasma treatment or performing any pretreatment such as primer treatment. As a result of intensive research into silicone and vinyl chloride resin with the aim of forming a silicone adhesive layer with excellent properties, we discovered that there is a combination of a soft vinyl chloride resin and silicone that provides strong adhesion. 58-203699 and Japanese Patent Application No. 58-203700. After that, further studies were conducted with the aim of finding a manufacturing method that would be advantageous. [Structure of the Invention] While conducting further improvement studies, the present inventors discovered that by adding organohydrogen polysiloxane to a soft vinyl chloride resin, adhesion with almost all addition polymerization type silicone rubbers was achieved. After discovering that this is possible, they conducted extensive research and completed the present invention. That is, the present invention provides at least an organohydrogensiloxane unit per 100 parts by weight of vinyl chloride resin.
Soft chlorinated resin, characterized by providing a hardened layer of addition polymerized silicone rubber on the surface of a molded product made of a soft vinyl chloride resin composition containing 0.01 to 10 parts by weight of organohydrogen polysiloxane of 30 mol% or more. An object of the present invention is to provide a composite molded product of a vinyl resin composition and an addition-polymerized silicone rubber. The soft vinyl chloride resin composition in the present invention includes vinyl chloride homopolymer, vinyl chloride-ethylene copolymer, vinyl chloride-vinyl acetate copolymer, vinyl chloride-ethylene-vinyl acetate terpolymer, The main ingredients are vinyl chloride-based copolymers such as vinyl chloride-acrylic acid copolymers and vinyl chloride-urethane copolymers, and organohydrogen polysiloxanes, plasticizers, stabilizers, etc. are blended with them. It is something that The organohydrogenpolysiloxane is a polysiloxane containing an organohydrogensiloxy group represented by the general formula (1), and contains at least 30 mol% or more, preferably 40 mol% or more, of organohydrogensiloxane units. More preferably, it is an organohydrogenpolysiloxane having at least one vinyl group in its molecule, which is represented by general formula (2) and has excellent compatibility with vinyl chloride resins. [In the formula, R ₁ : hydrogen group or monovalent hydrocarbon group having 3 or less carbon atoms, R ₂ to _{R 5} : monovalent hydrocarbon group having 6 or less carbon atoms, m: 0 or a positive integer of 100 or less ,
n: Positive integer between 3 and 100] [In the formula, R ₁ , R ₂ : one is a vinyl group and the other is a vinyl group or a monovalent hydrocarbon group having 3 or less carbon atoms,
_R3 to _R7 : monovalent hydrocarbon group having 6 or less carbon atoms,
X: 0 or a positive integer of 100 or less; Y: a positive integer of 3 or more and 100 or less Although it varies depending on the content of hydrogen siloxy groups, it is generally 0.01 to 10 parts by weight, preferably 0.5 to 5.0 parts by weight, per 100 parts by weight of vinyl chloride resin.
The optimum weight part is less than 0.01 part by weight, the adhesion is insufficient, and if it exceeds 10 parts by weight, it becomes too slippery and difficult to process, and the transparency is significantly impaired. become. In particular, for applications requiring transparency, it is suitable to add 0.01 to 10 parts by weight, preferably 1.0 to 5.0 parts by weight, of the vinyl group-containing organohydrogen polysiloxane represented by general formula (2). The plasticizers added to the vinyl chloride resin are not particularly limited, but include phthalate esters such as dioctyl phthalate, which have little adverse effect on adhesion with addition-polymerized silicone, epoxidized soybean oil, Preferably, epoxidized linseed oil or the like is used. Stabilizers that impart heat resistance and thermal stability include metal soaps such as calcium stearate, zinc stearate, barium stearate, magnesium stearate, and aluminum stearate, as well as organic metals of the metals in the above stabilizers. Stabilizers are particularly preferred, and one or more of the metals listed above are used in the stabilizer. However, organotin stabilizers,
Ester stabilizers such as butyl stearate and phosphoric acid stabilizers not only inhibit the curing of addition-polymerized silicone rubber, but also inhibit the effect of organohydrogen polysiloxane added to vinyl chloride resin. Because they are stored away, they cannot be used together. In the present invention, the addition polymerization type silicone rubber is, as is known, a vinyl group-containing polysiloxane represented by the general formula (3), an organohydrogen polysiloxane represented by the general formula (4), and silica as a reinforcing agent. A composition that can be solidified into an elastic body by addition polymerizing a composition made of an inorganic substance such as a platinum-based catalyst using a platinum-based catalyst, and is not particularly limited. Those to which epoxy compounds, carboxylic acid anhydrides, etc. are added as three components also fall into this category. [In the formula, _R1 to _R4 : same or different monovalent hydrocarbon groups having 6 or less carbon atoms, a: positive integer] [In the formula, R ₅ , R ₇ to _{R 10} : Same or different monovalent hydrocarbon groups having 6 or less carbon atoms, R ₆ : Hydrogen group or same or different monovalent hydrocarbon groups having 3 or less carbon atoms ,
b: an integer of 2 or more and 100 or less; c: 0 or a positive integer of 100 or less] The method for producing a composite molded product of a soft vinyl chloride resin composition and an addition-polymerizable silicone rubber in the present invention is not particularly limited. For example, a soft vinyl chloride resin composition to which organohydrogenpolysiloxane is added is kneaded with heated rolls, then pelletized, and the resulting molding material is used to extrude,
The molded product is molded by a pressing method, an injection molding method, etc., and the surface of the molded product is coated with an addition polymerization type liquid silicone rubber by a dipping method, a spraying method, etc., and then an addition polymerization type liquid silicone rubber is coated in a heating furnace, etc. When the rubber is cured, adhesive integration with the molded article is achieved almost at the same time. The present inventors previously wrote in Japanese Patent Application No. 58-203699,
By adding an excessive amount of organohydrogen polysiloxane in addition polymerized liquid silicone rubber to an extent that does not significantly impair the physical properties after solidification, strong adhesion with a specific formulation of soft vinyl chloride resin can be achieved. We have already found that this is achieved, and the adhesion mechanism is based on the organotypic bond in the addition-polymerized liquid silicone rubber against the residual vinyl groups in the vinyl chloride resin or the unsaturated double bonds generated by heating. It is estimated that this is the result of an addition reaction of hydrogen siloxy groups. The present invention is based on this technology, and is based on the fact that it has been discovered that by adding organohydrogen polysiloxane to soft vinyl chloride resin in advance, it becomes possible to bond with addition polymerized silicone rubber. The adhesion mechanism is based on the addition reaction of organohydrogensiloxy groups of organohydrogenpolysiloxane blended in soft vinyl chloride resin to vinyl groups in addition polymerizable silicone rubber, and It can be assumed that this is the result of the addition reaction of the organohydrogensiloxy group in the addition-polymerizable silicone rubber to the vinyl groups remaining in the rubber or to the unsaturated double bonds generated by heating, which proceeded in both directions. Here, an addition reaction between the organohydrogensiloxy groups of the organohydrogenpolysiloxane in the soft vinyl chloride resin composition and the vinyl groups in the vinyl chloride resin occurs during heating and kneading of the composition, and the organohydrogenpolysiloxane Although it is possible that the activity will decrease, since there is no catalyst in this soft vinyl chloride resin composition that can act as a catalyst for the addition reaction,
It is considered that this reaction rarely occurs inside the soft vinyl chloride resin composition. That is, the organohydrogenpolysiloxane added to the soft vinyl chloride resin composition starts an addition reaction only when it comes into contact with an addition-polymerizable liquid silicone rubber containing a platinum-based catalyst and is heated. death,
It is thought that this contributes to improving adhesive strength. [Effects of the Invention] The thus obtained composite molded product of the soft vinyl chloride resin composition and the addition-polymerized silicone rubber is strongly adhesively integrated, and exhibits the toughness of the soft vinyl chloride resin. Although it has rigidity, its surface is extremely smooth and coated to match the excellent antithrombotic properties and tissue compatibility of addition polymerized silicone rubber, making it suitable for a variety of applications, especially in the medical field. It is very useful. Hereinafter, the effects of the present invention will be explained with reference to Examples. Example 1 0.04 parts by weight of zinc stearate in terms of metal weight per 100 parts by weight of vinyl chloride resin (700D manufactured by Toyo Soda Co., Ltd.)
parts by weight, calcium stearate 0.02 parts by weight,
A basic soft vinyl chloride resin formulation (Table 1) was prepared by adding 50 parts by weight of diethylhexyl phthalate and 5 parts by weight of epoxidized soybean oil. On the other hand, as organohydrogenpolysiloxane No. 1, n-hexane contains 70% by weight of methylhydrogenpolysiloxane, which has a viscosity of about 40CS at 25°C and has about 70mol% of methylhydrogensiloxane units in one molecule. A solution was prepared. Further, as organohydrogen polysiloxane No. 2 having a vinyl group in the molecule, an n-hexane solution containing 70% by weight of polysiloxane represented by formula (5) was prepared. Next, to the above basic soft vinyl chloride resin formulation, organohydrogenpolysiloxanes No. 1 and No. 2 were added in the amounts shown in Table 1, and as a comparative example, they were not added, respectively, using a blender. At
After kneading at 190°C for about 7 minutes, the mixture was granulated. Each of these molding materials was press-molded at 180°C for 5 minutes to obtain a sheet with a thickness of 0.5 m/m. 20 from this sheet
Two sheets each with a size of m/m x 50 m/m were prepared, and the commercially available addition-polymerizable liquid silicone rubber shown in Table 1 was coated with a thickness of 1 m/m and a contact area of 20 m/m x 50 m/m each on the top and bottom.
m/m x approx. 25m/m with scissors,
The addition polymerization type liquid silicone rubber was cured by heating for 60 minutes in a 100°C temperature bath. The thus obtained test pieces were subjected to a 180° peel test at room temperature and their adhesive strengths were compared. The results are shown in Table 1, and it is clear that the soft vinyl chloride resin composition of the present invention can be firmly bonded and integrated with a general commercially available addition polymerization type liquid silicone rubber.

[Table] Example 2 Vinyl chloride resin (S-101 manufactured by Sumitomo Chemical Co., Ltd.)
To 100 parts by weight, 0.04 parts by weight of zinc stearate, 0.01 parts by weight of calcium stearate, 40 parts by weight of dioctyl phthalate, 6 parts by weight of epoxidized soybean oil, and methylhydrogen polysiloxane represented by formula (6). After mixing 1.2 parts by weight of a 50wt% n-hexane solution of
A tube of m/m was molded. On the other hand, a 20wt% toluene solution of addition polymerized liquid silicone rubber (KE-1920, manufactured by Shin-Etsu Chemical Co., Ltd.) was prepared. Next, the tube was cut into a length of 1 m, and about 10 c.c. of the toluene solution of the liquid silicone rubber was collected with a syringe, and the tube was fixed vertically and injected into the tube from above. Coating was performed only on the inside. After air-drying for 30 minutes, the tube was heated at 105° C. for 95 minutes in a hot-air dryer to obtain a two-layer tube (tube A) having a soft vinyl chloride resin on the outside and an addition-polymerized silicone rubber on the inside. A two-layer tube was prepared in exactly the same manner without adding methylhydrogen polysiloxane (comparative example tube).
I got it. These two tubes were immersed in a 30 wt % ethanol aqueous solution to remove internal air, and then ultrasonically cleaned for about 30 minutes. After cleaning, each tube was removed, cut lengthwise with a knife, and visually observed.
In the tube A of the present invention, the soft vinyl chloride resin layer and the addition-polymerized silicone rubber layer remained neatly adhered, whereas the inner surface of the tube of the comparative example had small pieces of peeled silicone rubber. It was observed that the addition-polymerizable silicone rubber was peeled off in a tube-like shape over several centimeters.

Claims (1)

[Scope of Claims] 1. A soft vinyl chloride resin composition containing 0.01 to 10 parts by weight of an organohydrogen polysiloxane containing at least 30 mol% of organohydrogen siloxane units based on 100 parts by weight of the vinyl chloride resin. A composite molded article of a soft vinyl chloride resin composition and an addition-polymerized silicone rubber, which is characterized by providing a cured layer of an addition-polymerized silicone rubber on the surface of the molded article. 2. A composite of the soft vinyl chloride resin composition and addition polymerizable silicone rubber according to claim 1, characterized in that the organohydrogen polysiloxane has at least one vinyl group in the molecule. Molded object. 3. Claim No. 3, characterized in that the metal in the stabilizer used in the soft vinyl chloride resin composition is one or more of calcium, zinc, barium, magnesium, and aluminum. A composite molded product of the soft vinyl chloride resin composition according to item 1 and addition polymerizable silicone rubber.