JPH083013B2 - Vinyl chloride resin composition - Google Patents

Description

TECHNICAL FIELD The present invention relates to a vinyl chloride resin composition having excellent antistatic properties.

(Prior Art) Vinyl chloride-based copolymers are widely used as various molded articles, sheets, and films because they are inexpensive, have good moldability, and have excellent properties. However, a molded product of a vinyl chloride-based copolymer is easily charged with electricity, which causes various obstacles. In order to prevent such electrification, it has been attempted to impart conductivity to the vinyl chloride copolymer.

As the vinyl chloride-based copolymer having conductivity, a resin composition obtained by blending a surfactant, carbon black, metal powder, conductive fibers, etc. (JP-A-59-49967 and JP-A-59-18734). Gazette) and a resin composition whose surface is coated with a surfactant (JP-A-56-10539). However, since the surfactant easily bleeds and falls off from the surface of the molded body, the antistatic effect is not maintained. If carbon black, metal powder, conductive fibers, etc. are added, the antistatic effect will not be maintained, but in order to obtain the desired conductivity, it is necessary to add a large amount of these conductive substances.
Therefore, it becomes expensive. A vinyl chloride resin composition having a noble metal or metal oxide adhered to its surface by vapor deposition, sputtering or the like has an excellent antistatic effect, but is expensive and has low productivity.

In order to solve such a drawback, there is a vinyl chloride resin molded product in which a conductive coating material in which a conductive material such as carbon black or metal powder is dispersed is used and which is applied on the surface. Although this molded article is inexpensive and exhibits an excellent antistatic effect, the conductive material is heterogeneous with respect to the resin, so that there is still a risk of bleeding or dropping.

(Problems to be Solved by the Invention) The present invention is to solve the above-mentioned conventional problems, and an object thereof is to provide a vinyl chloride resin composition that is inexpensive and has excellent antistatic properties. Especially.

(Means for Solving Problems) According to the present invention, by incorporating a monomer unit having conductivity into the skeleton of a vinyl chloride-based copolymer, and further introducing a metal salt forming a complex with this monomer unit. However, it was completed based on the inventor's knowledge that the antistatic property can be remarkably improved without bleeding or dropping.

The vinyl chloride resin composition of the present invention comprises a vinyl chloride copolymer having a vinyl chloride unit and a (meth) acryloic acid polyalkylene oxide ester unit represented by the following formula (1), lithium trifluoromethanesulfonate, At least one kind of polyhalogenated organic strong acid metal salt of lithium trifluoroacetate and lithium pentapropionate is contained, whereby the above object is achieved.

Here, R ₁ is a hydrogen atom or a methyl group, R ₂ is a polyoxyalkylene group having a degree of polymerization of _{2 to} 23, X is a hydrogen atom or an aliphatic or aromatic hydrocarbon group having 1 to 6 carbon atoms. Is.

The vinyl chloride unit is contained in the copolymer in an amount of 55 to 96% by weight, preferably 64 to 93% by weight. If it is less than 55% by weight, the properties as a vinyl chloride copolymer will be lost. If it exceeds 96% by weight, the desired antistatic property cannot be obtained.

The (meth) acrylic acid polyalkylene oxide ester unit is contained in the copolymer in an amount of 4 to 45% by weight, preferably 5% by weight.
It is contained in the range of up to 40% by weight. If it is less than 4% by weight, the desired antistatic property cannot be obtained. If it exceeds 45% by weight, properties such as thermal stability as a vinyl chloride copolymer are lost.

Examples of the (meth) acrylic acid polyalkylene oxide ester include polypropylene glycol methacrylate, polyethylene glycol methacrylate, polyethylene glycol polypropylene glycol methacrylate, polyethylene glycol polybutylene glycol methacrylate, methoxy polyethylene glycol methacrylate, methoxy polyethylene glycol acrylate, phenoxy polyethylene glycol acrylate,
Examples include butoxydiethylene glycol acrylate.

The vinyl chloride-based copolymer having a vinyl chloride unit and a (meth) acrylic acid polyalkylene oxide ester unit further contains a polyhalogenated organic strong acid metal salt to obtain a resin composition. The introduction of the polyhalogenated organic strong acid metal salt improves the antistatic property of the vinyl chloride copolymer. The polyhalogenated organic strong acid metal salt is contained in the resin composition in the range of 0.1 to 10% by weight. . If it is less than 0.1% by weight, the desired antistatic property cannot be obtained. Ten
When the amount is more than wt%, the polyhalogenated organic strong acid metal salt bleeds from the resin composition, which is not preferable. The polyhalogenated organic strong acid metal salt used in the present invention is at least one kind of polyhalogenated organic strong acid metal salt selected from lithium trifluoromethanesulfonate, lithium trifluoroacetate and lithium pentapropionate.

The vinyl chloride-based copolymer used in the vinyl chloride-based resin composition of the present invention may contain other monomer units copolymerizable with vinyl chloride within a range that does not impair the antistatic property. Examples of the monomer include ethylene,
Olefin such as propylene, vinyl acetate such as vinyl acetate and vinyl propionate, methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, lauryl (meth) acrylate, etc. There are non-functional (meth) acrylates and vinylidene chloride. Such a monomer unit is contained in order to improve Tg, viscosity and solubility of the copolymer.

As a method for synthesizing the copolymer, any known polymerization method can be used, and examples thereof include an emulsion polymerization method, a suspension polymerization method, a solution polymerization method, and a precipitation polymerization method. As a medium for the precipitation polymerization method, lower alcohols, especially methanol, are preferable because they are inexpensive. In the precipitation polymerization method, the copolymer is obtained as a fine powder, which facilitates molding. Polymerization temperature is 35 ~
The range is 70 ℃.

The vinyl chloride copolymer used in the vinyl chloride resin composition of the present invention has good solubility in an organic solvent. Examples of the soluble solvent include ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone, esters such as ethyl acetate and butyl acetate, chlorinated solvents such as ethylene dichloride and chloromethane, tetrahydrofuran and dimethylformamide. , Polar solvents such as dimethyl sulfoxide.

(Examples) The present invention will be described below with reference to Examples.

Example 1 An autoclave with a stirrer made of stainless steel with an internal volume of 20 was charged with 6 kg of methanol, 1 kg of water and α- as a polymerization initiator.
30 g of cumyl peroxy neodecanoate (Park Mill ND, manufactured by NOF CORPORATION) was charged. After exhausting the autoclave for 5 minutes with an aspirator, vinyl chloride monomer
2.1 Kg was added.

The 3 stainless steel containers (additional containers) that can be suspended are evacuated, and polyethylene glycol polybutylene glycol monomethacrylate (polyethylene glycol component polymerization degree 10, polybutylene glycol monomethacrylate component polymerization degree 5) (Blemmer 55PET-800: Japan (Oil and Fat Co.) (450 g) and 1 kg of methanol were charged by suction, and 1.45 kg of vinyl chloride monomer was then press-fitted. This addition container was shaken, the contents were mixed and dissolved in methanol, then hung on a spring balance, a flexible tube was attached to the valve at the bottom of the container, and it was connected to the addition nozzle of the polymerization reactor. .

The stirrer of the autoclave was rotated at 250 rpm and warm water was passed through the jacket to raise the temperature to 43 ° C. The polymerization reaction started at 43 ° C. At this point, the valve of the addition container was opened, and 47 g of a methanol solution of the monomer was added. afterwards,
As the polymerization progresses, every 5 minutes 53g 13 times, 62g
The addition of the monomer solution was repeated 13 times and 23 times from 59 g. 5 minutes after the addition is complete, place the autoclave at 25 ° C.
The polymerization reaction was stopped by cooling to. The internal pressure of the autoclave was 2.2 Kg / cm ² G at the start of the reaction and 2.9 Kg / cm at the end of the reaction.
It was cm ² G.

After completion of the polymerization reaction, unreacted vinyl chloride monomer was released into the atmosphere. Further, nitrogen gas was passed through the autoclave to completely remove the vinyl chloride monomer, and then the methanol slurry of the copolymer was taken out and filtered. The filtrate was vacuum dried at 50 ° C. for 24 hours to obtain 1.2 kg of a white powdery granular copolymer. The copolymer contained 71.1% by weight of vinyl chloride units and 28.9% by weight of polyethylene glycol polybutylene glycol monomethacrylate units. The average degree of polymerization of the copolymer was 1017.

The solubility of this copolymer in an organic solvent is such that when the copolymer is dissolved in a tetrahydrofuran / cyclohexanone mixed solvent (weight ratio 3/1) at 12% by weight, it completely dissolves to form a transparent solution. If a uniform casting film could be prepared using the solution, the solubility was considered good. If the above conditions were not satisfied, the solubility was evaluated as poor.

The copolymer was dissolved in a tetrahydrofuran / cyclohexane mixed solvent (weight ratio 3/1) to obtain a 12 wt% concentration solution. Further, to 50 g of this copolymer solution, 0.3 g of lithium trifluoroacetate was added to obtain a resin composition solution. This solution was poured into a glass plate, dried at room temperature for about 24 hours, and further dried under reduced pressure at 50 ° C. for 48 hours to prepare a casting film having a thickness of about 100 μm. The surface specific resistance value, volume specific resistance value, transparency and bleeding property of this film were measured as follows. The results of these measurements are shown in Table 1.

(1) Surface specific resistance value and volume specific resistance value After the casting film was left at 20 ° C. and 60% RH for 3 to 4 hours, it was measured according to JIS C-2318 using a digital electrometer TR-8652 (manufactured by Advantest). The resistance value was measured.

(2) Transparency The casting film was visually evaluated to have good transparency and poor transparency.

(3) Bleedability The castig film was allowed to stand at room temperature, and the case where cloudiness or a deposit was observed on the film surface was rated as bad, and the case where it was not observed at all was rated good.

Example 2 A solution of a vinyl chloride resin composition was obtained in the same manner as in Example 1 except that 0.4 g of lithium trifluoromethanesulfonate was added to 50 g of the copolymer solution. With respect to this resin composition, a casting film was prepared in the same manner as in Example 1, and the surface resistivity and volume resistivity, transparency and bleeding property were measured. The results are shown in Table 1.

Example 3 A vinyl chloride resin composition solution was obtained in the same manner as in Example 1 except that 0.1 g of lithium pentafluoropropionate was added to 50 g of the copolymer solution. With respect to this resin composition, a casting film was prepared in the same manner as in Example 1, and the surface resistivity and volume resistivity, transparency and bleeding property were measured. The results are shown in Table 1.

Example 4 83.1 wt% vinyl chloride units in the copolymer, and octaethylene glycol monomethacrylate units
A copolymer was obtained in the same manner as in Example 1 except that the content was 16.9% by weight. The average degree of polymerization of this copolymer was 815. The solubility of the copolymer in an organic solvent was measured by the same method as in Example 1.

A solution of a vinyl chloride resin composition was obtained in the same manner as in Example 1 except that 0.20 g of lithium trifluoroacetate was added to 50 g of this copolymer solution. With respect to this resin composition, a casting film was prepared in the same manner as in Example 1, and the surface resistivity and volume resistivity, transparency and bleeding property were measured. The results are shown in Table 1.

Example 5 A solution of a vinyl chloride resin composition was obtained in the same manner as in Example 1 except that 0.1 g of lithium trifluoromethanesulfonate was added to 50 g of the same copolymer solution as in Example 4. With respect to this resin composition, a casting film was prepared in the same manner as in Example 1, and the surface resistivity, volume resistivity, transparency and bleeding property were measured. The results are shown in Table 1.

Example 6 A solution of a vinyl chloride resin composition was obtained in the same manner as in Example 1 except that 0.4 g of lithium pentafluoropropionate was added to 50 g of the same copolymer solution as in Example 4. With respect to this resin composition, a casting film was prepared in the same manner as in Example 1, and the surface resistivity and volume resistivity, transparency and bleeding property were measured. The results are shown in Table 1.

Comparative Example 1 In Example 1, a homopolymer having a vinyl chloride unit of 100% by weight was obtained without using the addition container and thereafter performing no addition. Further, a vinyl chloride resin solution was prepared in the same manner as in Example 1. To this resin solution 50, 0.1 g of lithium trifluoroacetate was added, and a casting film was prepared in the same manner as in Example 1, and the surface specific resistance value and volume specific resistance value, transparency and bleeding property were measured. . The results are shown in Table 1.

Comparative Example 2 A casting film was prepared in the same manner as in Example 1 except that the same vinyl chloride-based copolymer as in Comparative Example 1 did not contain lithium trifluoroacetate. The specific resistance value, transparency, and bleeding property were measured. The results are shown in Table 1.

As is clear from Examples and Comparative Examples, the vinyl chloride resin composition of the present invention has a low volume resistivity value and a surface resistivity value, and is excellent in conductivity. Therefore, the antistatic property is high. It also has good transparency and bleeding properties. Moreover, the vinyl chloride-based copolymer constituting this resin composition has excellent solubility in organic solvents. The resin composition containing no polyhalogenated organic strong acid metal salt has good transparency and bleeding property, but has high volume resistivity value and surface resistivity value and lacks conductivity. Therefore, antistatic cannot be sufficiently performed.

(Effects of the Invention) The vinyl chloride resin composition of the present invention is excellent in conductivity and therefore inexpensive and has excellent antistatic properties. The antistatic property can be maintained for a long time. Moreover, the solubility, transparency and bleeding property are good. Therefore, the resin composition of the present invention can be effectively used for a conductive sheet, a conductive paint, a conductive treatment material, an antistatic property and the like.

Claims (3)

[Claims] 1. A vinyl chloride copolymer having a vinyl chloride unit and a (meth) acrylic acid polyalkylene oxide ester unit represented by the formula (1) is added to lithium trifluoromethanesulfonate, lithium trifluoroacetate and pentafluoropropion. A vinyl chloride resin composition containing at least one metal salt of a polyhalogenated organic strong acid among lithium oxides. Here, R ₁ is a hydrogen atom or a methyl group, R ₂ is a polyoxyalkylene group having a degree of polymerization of _{2 to} 23, X is a hydrogen atom or an aliphatic or aromatic hydrocarbon group having 1 to 6 carbon atoms. Is. 2. The vinyl chloride resin composition according to claim 1, wherein the vinyl chloride unit is contained in the copolymer in an amount of 55 to 96% by weight. 3. The metal salt of a polyhalogenated organic strong acid comprises:
The vinyl chloride resin composition according to claim 1, wherein the vinyl chloride resin composition is contained in the range of 1 to 10% by weight.