JPS6116952A - Preparation of vinyl chloride resin composition - Google Patents

Abstract

PURPOSE:To produce a composition for forming a tube having smooth surface without lowering molding properties of extrusion, by dissolving or swelling an acrylic resin in a plasticizer, blending it with vinyl chloride resin. CONSTITUTION:An acrylic resin is dissolved or swelled in a plasticizer, and blended with vinyl chloride resin. An acrylic ester (co)polymer, polyacrylic acid methyl ester, etc. shown by the formula CH2=CR-COOR<1> (R is H, or lower alkyl; R<1> is 1-18C alkyl) is used as the acrylic resin. <=100pts.wt. acrylic resin is blended with 100pts.wt. plasticizer and stirred at 20-200 deg.C.

Description

[Detailed description of the invention] "Industrial application field" The present invention relates to a blood transfusion tube and a dialysis tube.

The present invention relates to a method for producing a vinyl chloride resin composition suitable for molding medical tubes such as heart-lung tubes and various cannulae.

``Prior Art'' Medical tubes preferably allow blood to flow smoothly, and are also preferably transparent so that blood flow can be observed. As the material for these medical tubes and cannulae, plasticized vinyl chloride resin is often used because it has excellent transparency and can provide desired flexibility. Medical tubes are usually manufactured by extrusion molding, but in order to facilitate extrusion molding, a vinyl chloride resin composition with a small amount of acrylic resin such as polymethyl methacrylate added as a molding aid may be used. (``Polyvinyl chloride, its chemistry and industry'' (published by Asakura Shoten), p. 209, Fukisho).

However, although simply adding and mixing acrylic resin to vinyl chloride resin has the effect of improving extrusion, the acrylic resin is not completely and uniformly mixed with the vinyl chloride resin during extrusion molding, resulting in so-called "one piece" on the tube surface. When unevenness is formed due to unmelted particles of the acrylic resin called acrylic resin, and especially when spots are formed on the inner surface of the tube, the flow of the liquid is disturbed and air bubbles are drawn in, making it difficult to use as a medical tube. I wasn't able to use it satisfactorily. Of course, the amount of puttu generated was.

The particle size of the acrylic resin varies and is affected by the molecular weight and tube molding temperature.

"Problems to be Solved by the Invention" The inventors of the present invention have intensively studied methods for manufacturing medical tubes with no lumps and a smooth surface. Rather than blending, the acrylic resin is dissolved in a plasticizer in advance, or the acrylic resin is swollen with a plasticizer, and then tri-blended with a vinyl chloride resin. The present invention was completed by discovering that a tube with a smooth surface without any bumps can be manufactured without deteriorating its properties.

That is, one object of the present invention is to provide a method for producing a vinyl chloride resin composition, which makes it possible to obtain a molded article having a smooth surface without bumps.

"Structure of the Invention" The gist of the present invention is a method for producing a vinyl chloride resin composition containing an acrylic resin.

Acrylic resin is accepted! 1! A method for producing a vinyl chloride resin composition, which is characterized in that the composition is mixed with a vinyl chloride thread resin after being dissolved in a 1:1 solution or swollen with a plasticizer.

The present invention will be described in detail.

The acrylic resin contained in the vinyl chloride resin composition is
It is not particularly limited. Usually, a polymer whose main component is an acrylic acid monomer such as acrylic acid, methacrylic acid, or an ester thereof is used.
It may be a 4L German polymer or a copolymer. Furthermore, the comonomer to be copolymerized with the acrylic acid monomer may be another acrylic acid monomer or a comonomer other than the acrylic acid monomer. In the present invention, one of the various noacrylic acid monomers has the following general formula [1] 0H2=OR-00OR' . . . [1
[In the formula, R represents a hydrogen atom or a lower alkyl group, and R' represents an alkyl group having 7 to 1 carbon atoms. ] Preferred are acrylic esters represented by the following.

Specifically, examples include methyl acrylate, ethyl acrylate, n-propyl acrylate, 1-propyl acrylate, n-butyl acrylate, 1-butyl acrylate, and λ-ethylhexyl acrylate. , acrylic acid-
n-octyl, dodecyl acrylate, hexadecyl acrylate, octadecyl acrylate, methyl methacrylate, ethyl methacrylate, propyl methacrylate, n-butyl methacrylate, 1-butyl methacrylate, hemosil methacrylate, methacrylic acid -n-octyl, 2-ethylhexyl methacrylate, decyl methacrylate,
Examples include, but are not limited to, cyclohexyl methacrylate and octadecyl methacrylate.

Comonomers other than the acrylic acid monomer copolymerized with these acrylic esters include acrylonitrile, methacrylonitrile, vinyl acetate, beer propionate, vinyl laurate, dibutyl maleate, diethyl maleate, diethyl fumarate. , diptyl fumarate, vinyl methyl ether, vinyl butyl ether h
Examples include 1-butadiene and styrene, which are copolymerized into the acrylic resin within a range that does not impair various physical properties such as extrusion performance and thermal stability of the vinyl chloride resin composition.

Alternative acrylic resins include, for example, polymethyl acrylate and polymethyl methacrylate.

Mether-butadiene-sterene methacrylate copolymer (
MBS). The molecular weight of these acrylic resins is generally in the range of 300,000 to ZSO0,000, and the particle size is preferably 100 μm or less.

In the present Genmei method, the plasticizer to dissolve or swell the acrylic resin may be one commonly used as a plasticizer for vinyl chloride resins.

It is not particularly limited. For example, phthalic acid di-n-
Butyl, di-n-butyl phthalate, di-λ-enalhexyl phthalate, diisooctyl phthalate, octyldecyl phthalate, diisodecyl phthalate, butylbenzyl phthalate.

Phthalic acid plasticizers such as di-ethylhexyl isophthalate or higher alcoholic acid esters having about 73 carbon atoms, n-octyl-n-decyl trimellitate, IJ-,2-ethylhexyl trimellitate, Trimellitic acid plasticizers such as triisodecyl trimellitate and tri-n-octyl trimellitate, dicoethylhexyl adipate, di-n-decyl adipate, diisodecyl adipate, dicoethylhexyl azelain, dibutyl sebacate, insects Fatty acid ester thread plasticizers such as dicoethylhexyl basate, tributyl phosphate, 1·'-Ω-ethylhexyl phosphate, coethylhexyl diphenyl phosphate, Nisdel phosphate plasticizers for tricresyl phosphate notes, adipic acid A polyester obtained by esterifying the terminal carboxylic acid group of a polycondensate of adipic acid and propylene glycol with co-ethylhexanol, a polyester obtained by esterifying the terminal carboxylic acid group of a polycondensate of adipic acid and propylene glycol with two-ethylhexanol, The terminal carboxylic acid group of the M condensate of adipic acid and he-3-butanediol is esterified with Koech's Ruhexal L [VolJ ester.

A polyester obtained by polycondensing azelaic acid and ethylene glycol and esterifying it with the terminal carboxylic acid group t-noethylhenol, azelaic acid and 3-
Polyester in which the terminal carboxylic acid group of a polycondensate with butanediol is esterified with ethylhexanol, polyester in which the terminal carboxylic acid group of a polycondensate of phthalic acid and ethylene glycol is esterified with coethylhexanol, and adipic acid Polymeric yarn plastics such as polyester with lauric acid esterified in the terminal hydroxyl group of M condensate with ethylene glycol, polyester with lauric acid esterified in the terminal hydroxyl group of polycondensate of adipic acid and ↓, 123-butanediol, etc. agent, epoxidized soybean oil, epoxidized linseed oil, epoxy ratio? 1tIJj
Examples include epoxy plasticizers such as it-fatty acid-Ω-ethylhexyl and liquid epoxy resin, and these may be used alone or in combination of two or more. In the method of the present invention,
From the point of view of economy, 7-tal Sameitocho plasticizer is generally used, but in order to maintain the performance required for vinyl chloride resin compositions, trimellitic acid plasticizers, fatty acid ester plasticizers, and phosphate esters are also used. Plasticizers and polymeric plasticizers may be used alone or in combination.

Epoxy plasticizers5 are usually used in combination with other plasticizers for the purpose of improving thermal stability.

The vinyl chloride resin used in the method of the present invention includes vinyl chloride or a mixture of vinyl chloride and a comonomer copolymerizable with it. All those manufactured by conventional methods such as the above can be used. Therefore, examples of comonomers that can be copolymerized with vinyl chloride include vinyl esters such as vinyl acetate, vinyl globion, and vinyl laurate; acrylic esters such as methyl acrylate, ethyl acrylate, and butyl acrylate; methyl methacrylate; Methacrylic acid esters such as ethyl methacrylate.

Tuma-A-[? Esters.

Vinyl methyl ether, vinyl methyl ether.

Vinyl ethers such as vinyl octyl ether.

Vinyl cyanides such as acrylonitrile and methacrylonitrile, α-olefins such as ethylene, propylene and styrene, and vinylidene chloride.

Examples include vinylidene 210genide or vinyl halides other than vinyl chloride such as vinyl bromide, and these comonomers are used in an amount of 30% by weight or less, preferably 10% by weight or less in the constituent components of the vinyl chloride resin. It will be done. Of course, the comonomer.

It is not limited to what is described above.

In the method of the present invention, after dissolving the acrylic resin in a plasticizer,
Alternatively, after being swollen with a plasticizer, it is mixed with a vinyl chloride resin to produce a vinyl chloride resin composition.

Vinyl chloride resin and acrylic resin f: Mixing of the dissolved or swollen plasticizer is carried out, for example, in the following manner.

(2) Mix a plasticizer in which an amount of acrylic resin necessary for forming one composition is dissolved in a predetermined amount of vinyl chloride resin.

■ Add the amount of acrylic resin necessary to form one composition to a predetermined amount of vinyl chloride resin, then take the required amount of the acrylic resin from a concentrated plasticizer solution of acrylic resin and mix it with the plasticizer. .

The dissolution of the acrylic resin in the plasticizer is preferably at most 100 parts by weight of the acrylic resin per 700 parts by weight of the plasticizer!
θ parts by weight, especially at a ratio of -20 parts by weight or less, 20-20
Temperature range of 0℃.

Preferably, it is carried out at a temperature range of 60~/JO"C, while stirring slowly and frequently. 700 parts by weight of polymethyl methacrylate is added to 10θ parts by weight of a plasticizer at a temperature of ioo
It dissolves very easily in 1 hour at ℃. At a temperature lower than -20°C, it takes time to melt, whereas at a temperature higher than 200°C, the plasticizer volatilizes and the acrylic resin or plasticizer tends to deteriorate. If the amount of plasticizer used for the acrylic resin is less than the above regulations, the viscosity may be too high, and in some cases the acrylic resin may not be completely dissolved in a short period of time, causing blistering. Easy to use. Furthermore, acrylic resins swollen with plasticizers also have improved effects on lump formation. In general, phthalate plasticizers such as phthalate-gecoethylhexyl have excellent solubility in acrylic resins, fatty acid ester plasticizers such as adipic acid-gecoethylhexyl, and tri-coethylhexyl trimellitate plasticizers. Mellitic acid plasticizers, polymeric plasticizers, etc. have poor solubility) and often only cause swelling, and the latter three are usually used in combination with phthalic acid plasticizers.

Although the amount of plasticizer contained in a vinyl chloride resin composition varies depending on the moldability, processability, workability, and use of the molded product, it is generally determined based on 100 parts by weight of the vinyl chloride thread resin. The amount is in the range of 30-200 parts by weight, preferably 200 parts by weight. On the other hand, the amount of acrylic resin contained in one composition is 0.7 to 10 parts by weight, preferably 0.1 to 10 parts by weight, based on 100 parts by weight of vinyl chloride resin.
! The weight ranges particularly from 0 to 3 parts by weight.

In addition to the above-mentioned essential components, the composition according to the method of the present invention includes:
Additives commonly used in vinyl chloride thread resins, such as stabilizers, antioxidants, ultraviolet absorbers, filler 1 colorants, mold release agents, etc. may be included.

A vinyl chloride resin composition prepared by the method of the present invention is as follows.

Simply, it is prepared by uniformly blending the above-mentioned essential components and other additives as necessary using a mixing agitator such as a super mixer, a ribbon mixer, or a change can mixer. The composition is.

It can be used as is for extrusion molding of tubes, etc.

Furthermore, specifically, in order to produce a vinyl chloride resin composition from a vinyl nonachloride polymer obtained by, for example, 5M turbid polymerization or bulk polymerization, a vinyl chloride resin, a plasticizer in which an acrylic resin is dissolved, and necessary Add other additives depending on the situation, mix uniformly with a ribbon mixer, etc., and dry up. Furthermore, if necessary, the composition may be heated and melted in a mixer such as a roll or Banbury (Kisa-1 extruder), then formed into a sheet or strand, and then formed into a pellet-like composition using a sheet cutter or pelletizer. .and.

The resin composition is generally made into a molded article by extrusion molding, injection molding, or blow molding. In addition, a polyvinyl chloride resin composition overflowing super mixer, two--
A plastisol composition is prepared by uniformly mixing the mixture using a mixer such as a stirrer.

The sol composition is made into a molded article by rotational molding or slush molding.

"Effects of the Invention" The vinyl chloride resin composition produced by the method of the present invention is produced by dissolving vinyl chloride resin in a state in which an acrylic resin mainly used as a molding aid is once dissolved in a plasticizer or in a state swollen with a plasticizer. Since the acrylic resin is blended into the base resin, the acrylic resin is uniformly contained in the composition without any lumps 9, and even if a molded article is manufactured from the composition, the molded article will not have lumps caused by the acrylic resin. There isn't.

In particular, tubes formed by extrusion molding have smooth inner surfaces, excellent transparency, and elasticity and roundness that allow them to maintain the shape of the extrusion die. Even when liquid flows through this tube, no turbulence occurs and no air bubbles are trapped.

Therefore, the vinyl chloride resin composition produced by the method of the present invention has high utility value as a molding material for various medical tubes such as blood transfusion tubes, dialysis tubes, and heart-lung tubes.

"Practice" Next, the method of the present invention will be explained in detail with reference to Examples, but the present invention is not limited to the following Examples unless the gist thereof is exceeded.

In addition, "parts" in the examples indicate "parts by weight."

15 Example/ Vinyl chloride resin (average degree of polymerization p/jθ0.10
0 parts suspension polymerization homopolymer, PVc) Dicoethylhexyl phthalate (DOP)
J-0 part polymethyl methacrylate
2 parts (molecular weight approximately 600,000, PMMA) Oa-zn stabilizer
/, Yobe 1j A vinyl chloride resin composition having the above-mentioned compounding density was produced as follows.

(11PMMA (D powder, 2 parts 1 DOP, 2 parts K)
XJ, n.

Stirred at 0C for 6 portions.

After confirming that PMMA is dissolved in DOP, convert this DOP into DOP with PVO1 remaining.

I put it in a super kenkiza with a stabilizer and dried it up.

(Add 2 parts of 21PMMA powder to the DOP!θ part,
Stirred for io minutes at 0°C.

After confirming that PMMA was dissolved in DOP, this DOP'i PVO and a stabilizer were placed in a super mixer and dried up.

(3) PMMAO powder, 2 parts Do P J' O
mK 7JD.

The mixture was stirred at 60°C for 60 minutes.

After confirming that PMMA was dissolved in DOP, this DOP was placed in a super mixer together with PVA and a stabilizer and dried up.

These vinyl chloride resin compositions @, /? At 0℃.

A tube with an inner diameter of 1 and a wall thickness of /■ was extruded using a tube extrusion die. The transparency of the tube was visually judged, and the tube was cut open and the smoothness of the inner surface and the presence or absence of lumps were observed using an optical microscope. The number of particles on the inner surface of length α was measured using a microscopic microscope.

For comparison, the following molding was performed in the same manner as in Example 1, and the observation results are shown in Table 1.

(4) Without pre-dissolving PMMA in plasticizer.

PVO, pMuA, DOP, and stabilizer were placed together in a super mixer and dried.

(5) Dry up pva%DOP and stabilizer in a super mixer, then add PMMA powder.

Nucleation occurred on the surface of the dry up powder.

Table / Table Example λ 7 parts of polymethyl methacrylate (600,000 per molecule) as DOP
700 parts of PVO (p/300 suspension polymerization homopolymer), 700 parts of epoxidized flax oil
, ca-zn stabilizer/, 1 part, stearic acid lubricant θ
- 6 parts were placed in a super mixer and dried up uniformly to obtain a powdered vinyl chloride resin composition. The composition was heated to an inner diameter of about 101 M at a temperature of i, 5''o C and 2σO C.
m, wall thickness approximately 2 cm (extruded into D tube).

The tube had a JIS cough hardness of 7θ and was normally perfectly round.

The transparency of this tube was visually judged, and the smoothness of the inner surface of the tube, the presence or absence of lumps, and the degree of coloration (no Ti coloring after heating for 2 hours in an open environment at 100°C) were examined, and the results are shown in Table 2. friend.

From the results of Table 2 Examples, it was found that acrylic resin was dissolved in plasticizer and
The composition obtained by blending with the vinyl chloride resin showed no sagging in any case, and was found to be suitable as a medical tube molding material.

Claims (3)

[Claims] (1) In the method for producing a vinyl chloride resin composition containing an acrylic resin, the vinyl chloride resin composition is characterized in that the acrylic resin is dissolved in a plasticizer or swollen with a plasticizer and then mixed with a vinyl chloride resin. How things are made. (2) The acrylic resin has the general formula CH_2=CR-COOR^1...[1] [In the formula, R is a hydrogen atom or a lower alkyl group, and R^1 is an alkyl group having 1 to 18 carbon atoms. ] A method for producing a vinyl chloride resin composition according to claim 1, which is a polymer or copolymer of an acrylic ester represented by the following. (3) The method for producing a vinyl chloride resin composition according to claim 2, wherein the acrylic resin is polymethyl acrylate or polymethyl methacrylate.