JP2903089B2 - Manufacturing method of halogen-containing thermoplastic resin moldings - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a halogen-containing thermoplastic resin molding having excellent properties such as processability, appearance, strength, hydrophilicity, oil / solvent resistance, and gas barrier properties. The method relates to a method for producing the same.

2. Description of the Related Art Vinyl chloride polymers are relatively inexpensive resins and have excellent properties such as transparency, mechanical properties, workability, etc., so that films, sheets, hoses, flexible containers, canvas, leather, It is used for a wide range of applications including waterproof sheets, shoe soles, sponges, wire covering materials, and daily necessities.

The vinyl chloride polymer is a resin having the above-mentioned advantages, but has disadvantages such as poor processability, hydrophilicity, oil and solvent resistance, gas barrier properties, and adhesion to a substrate.

Therefore, in order to improve the processability, hydrophilicity, and other properties of a vinyl chloride polymer, a polymer blend of a vinyl chloride polymer with a modifying resin has been performed. Incorporation of a saponified vinyl acetate copolymer has been performed.

For example, JP-A-52-69955 discloses a vinyl chloride polymer barrier packaging composition consisting essentially of a mixture of a vinyl chloride polymer and 10 to 30% by weight of an ethylene / vinyl alcohol copolymer. Have been.

JP-A-60-238345 discloses thermoplastic resins (including vinyl chloride polymers), saponified ethylene-vinyl acetate copolymers, and groups I, II and III of the periodic table.
A resin composition comprising a salt or an oxide containing at least one element selected from the group is disclosed, and it is described that this composition has significantly improved compatibility.

JP-B-59-39464 discloses a vinyl chloride polymer-polyurethane alloy obtained by reacting a polyol with a polyisocyanate in the presence of a vinyl chloride polymer. However, no consideration is given to combining this coexisting reaction polymer alloy with a vinyl alcohol-based polymer.

However, the method of blending a saponified ethylene-vinyl acetate copolymer with a halogen-containing thermoplastic resin such as a vinyl chloride-based polymer is difficult due to the hydrophilicity, oil / solvent resistance, and gas. Although properties such as barrier properties are improved,
Both resins are inherently hardly compatible with each other, so that it is difficult to perform long-run molding, and there is a problem that a molded product obtained by melt molding shows foreign matters and coloring, and also deteriorates mechanical properties.

In this regard, the composition described in Japanese Patent Application Laid-Open No. 60-238345 has an effect of improving compatibility in terms of compatibility, but there is naturally a limit to the improvement of compatibility by the addition of salts and oxides, and practical use is not practical. From a technical point of view, there is still room for improvement.

The present invention is to improve the various properties by blending a vinyl alcohol-based polymer with a halogen-containing thermoplastic resin, by using a specific coexisting reaction composition as at least a part of the halogen-containing thermoplastic resin, the conventional It tries to solve the problem.

Means for Solving the Problems That is, the method for producing a halogen-containing thermoplastic resin-based molded article of the present invention comprises a polyurethane content of 10 to 10 obtained by reacting a polyol and a polyisocyanate in the presence of a vinyl chloride-based polymer. Halogen-containing thermoplastic resin (A) 100 comprising 90 to 100% by weight of a vinyl chloride polymer-polyurethane coexisting reaction composition (a1) and 0 to 99.9% by weight of another halogen-containing polymer (a2) It is characterized in that 0.1 to 100 parts by weight of a melt-moldable vinyl alcohol-based polymer (B) is blended with parts by weight and melt-molded.

 Hereinafter, the present invention will be described in detail.

Halogen-Containing Thermoplastic Resin (A) The halogen-containing thermoplastic resin (A) may be a vinyl chloride polymer-polyurethane coexisting reaction composition (a1) alone, or may be a coexisting reaction composition (a1) and another halogen-containing resin. It consists of a polymer (a2).

<Coexisting reaction composition (a1)> The vinyl chloride polymer-polyurethane coexisting reaction composition (a1) is obtained by reacting a polyol and a polyisocyanate in the presence of a vinyl chloride polymer.

As a reaction method, a method in which a polyol is added to a powdery or particulate vinyl chloride polymer to be impregnated, and then a polyisocyanate is added to form a polyurethane in the vinyl chloride polymer powder or particles. It is preferably adopted. In addition, a method in which a powdery or particulate vinyl chloride-based polymer, a polyol and a polyisocyanate are mixed together to form a polyurethane is used.

The content of polyurethane in the resulting coexisting reaction composition is
It is necessary that the content be in the range of 10 to 90% by weight, and when the content of the component is less than or greater than this range, the effect of improving the compatibility is insufficient.

Here, as the vinyl chloride polymer, in addition to a homopolymer of vinyl chloride, a copolymer of vinyl chloride and one or more comonomers is used. Other comonomers include vinyl acetate, ethylene, vinylidene chloride and the like.

As a polyol among urethane raw materials, for example,
Polyester polyols (condensed polyester polyol, lactone polyester polyol, polycarbonate diol, etc.), polyether polyols and the like are used. Among these, the condensed polyester polyols include adipic acid, succinic acid, azelaic acid, pimelic acid, sebacic acid, dicarboxylic acids such as phthalic acid or lower alkyl esters thereof, ethylene glycol, 1,4
-Butanediol, 1,6-hexanediol, aliphatic diols having no side chain such as 1,10-decamethylene glycol, 1,2-propylene glycol, 1,3-butanediol, 2,5-dimethyl-2 , 5-hexanediol, 2,2-diethyl-1,3-propanediol, neopentyl glycol and the like, and a reaction with an aliphatic diol having a side chain. Examples of the polyether polyol include polyethylene glycol, polypropylene glycol, polytetramethylene glycol, glycerin-based polyalkylene ether glycol, and the like.

Among the urethane raw materials, examples of the polyisocyanate include tetramethylene diisocyanate, pentamethylene diisocyanate, hexamethylene diisocyanate, lysine diisocyanate, cyclohexylmethane diisocyanate, 2,2,4- or 2,4,4-trimethylhexamethylene diisocyanate, and isopropylidene. Aliphatic or alicyclic diisocyanates such as bis (4-cyclohexyl isocyanate), methylcyclohexane diisocyanate, isophorone diisocyanate, and 2,4-
Or 2,6-tolylene diisocyanate, diphenylmethane-4,4'-diisocyanate, 3-methyldiphenylmethane-4,4'-diisocyanate, m- or p-
Phenylene diisocyanate, chlorophenylene-2,4
-Diisocyanate, naphthalene-1,5-diisocyanate, xylylene diisocyanate, tetramethyl xylylene diisocyanate, adducts of polyhydric alcohol and polyisocyanate, and the like are used.

In the urethanization reaction, a chain extender such as a polyhydric alcohol and a polyamine may be used.

<Other halogen-containing polymer (a2)> Examples of the halogen-containing polymer (a2) other than the coexisting reaction composition (a1) include a vinyl chloride polymer, a vinylidene chloride polymer, a chlorinated polyethylene, and a chlorinated polypropylene. Chlorinated ethylene-vinyl acetate copolymer, chlorosulfonated polyethylene, and the like. In particular, a vinyl chloride polymer, that is, a homopolymer of vinyl chloride or a copolymer of vinyl chloride and another comonomer is important.

Vinyl alcohol-based polymer (B) As the vinyl alcohol-based polymer (B), a melt-moldable homopolymer or copolymer of vinyl alcohol,
For example, polyvinyl alcohol having a relatively low polymerization degree, partially saponified polyvinyl acetate, post-modified polyvinyl alcohol (acetalized product, ketalized product, cyanoetherified product, etc.), a monomer copolymerizable with vinyl acetate (for example, ethylene) Olefins such as propylene, isobutene, α-octene, α-octadecene, unsaturated carboxylic acids or salts thereof, partial alkyl esters, complete alkyl esters, nitriles, amides, anhydrides, unsaturated sulfonic acids or salts thereof, other than vinyl acetate And saponified copolymers of vinyl acetate and the like. However, the copolymerization ratio of a monomer copolymerizable with vinyl acetate is required to be 75 mol% or less for ethylene and 30 mol% or less for monomers other than ethylene.

Among them, ethylene-vinyl acetate copolymers having an ethylene content of 20 to 75 mol% (preferably 25 to 60 mol%) and a degree of saponification of the vinyl acetate portion of 50 mol% or more (preferably 70 mol% or more) When the copolymerization is out of the above range, the effect of improving the properties of the halogen-containing thermoplastic resin (A) is insufficient. In addition, as long as it has the above-mentioned copolymer composition, it may contain a small amount of comonomer.

Among the vinyl alcohol polymers (B), a low ash / low alkali metal vinyl alcohol polymer having a melting temperature of 200 ° C. or lower and having an ash content and an alkali metal content of a certain amount or less is preferable. .

Since the halogen-containing thermoplastic resin is generally molded at a temperature of 200 ° C. or less, if the melting temperature exceeds 200 ° C., the vinyl alcohol polymer does not completely melt, and the compatibility dispersion is incomplete. Desirable physical properties cannot be obtained as a composition molded article.

If the ash content and the alkali metal content exceed predetermined amounts, the halogen-containing thermoplastic resin is likely to be colored or decomposed during molding.

Generally, a saponified vinyl acetate copolymer is produced by saponifying a vinyl acetate copolymer with an alkali catalyst. However, industrial water and reagents used contain metal salts as impurities, and the saponification catalyst (alkali metal hydroxide) remains as an alkali metal acetate after the reaction. Therefore, these impurities and the alkali metal acetate are contained in the resin precipitated and filtered from the saponification solution. Resin copolymerization component content, degree of saponification, or saponification conditions, but cannot be stated unconditionally, but usually the ash content in the saponified vinyl acetate copolymer obtained above is, for example, about 5,000 to 50,000 ppm, The alkali metal content is, for example, about 4000 to 40,000 ppm.

Also, in the production of polyvinyl alcohol or a subsequently modified product, an acid or alkali is used as a catalyst,
When an acid is used as a catalyst, a metal hydroxide or a carbonate is used in the neutralization step after the reaction, so that a considerable amount of alkali metal is contained.

Here, the ash content means that the saponified vinyl acetate copolymer is placed on a platinum evaporating dish, carbonized using an electric heater and a gas burner, placed in an electric furnace at 400 ° C, heated to 700 ° C, and further heated to 700 ° C. After completely incinerated for 3 hours, taken out of the electric furnace, allowed to cool for 5 minutes, left in a desiccator for 25 minutes, and weighed out the ash.

The alkali metal is quantified by an atomic absorption method using a solution obtained by ashes a saponified vinyl acetate copolymer in the same manner as in the ash measurement and then dissolving the ash in a hydrochloric acid aqueous solution under heating.

In the present invention, the ash content defined above is 300 p
pm or less, preferably 50 ppm or less, more preferably 20 ppm
It is particularly preferable to use a low ash / low alkali metal ethylene-vinyl acetate copolymer saponified product having an alkali metal content of 200 ppm or less, preferably 35 ppm or less, more preferably 5 ppm or less. The ash content and alkali metal content are preferably as small as possible within the above range, but from the industrial point of view, there is a limit to purification, so the lower limit is about 1 ppm for ash content and about 0.5 ppm for alkali metal content.

To obtain the vinyl alcohol polymer having a low ash content and a low alkali metal content as described above, the powder, particles and pellets of the polymer are sufficiently washed with an acid, particularly a weak acid in an organic solvent such as water or methanol, and the ash content is reduced. After removing salts causing alkali metal or alkali metal, it is more preferable to wash with water or an organic solvent such as methanol to remove the acid attached to the resin, and then dry the resin. The water used for preparing or washing the aqueous solution described above or below is deionized water.

Here, as the weak acid, acetic acid, propionic acid, glycolic acid, lactic acid, adipic acid, azelaic acid, glutaric acid, succinic acid, benzoic acid, isophthalic acid, terephthalic acid and the like are used. Usually, those having a pKa at 25 ° C of 3.5 or more are useful.

After the treatment with the weak acid, before or after washing with water or an organic solvent such as methanol, a diluted strong acid such as oxalic acid or maleic acid at 25 ° C.
Further treatment with an aqueous solution of an organic acid having a pKa of 2.5 or less, phosphoric acid, sulfuric acid, nitric acid, hydrochloric acid or the like is desirable. Thereby, the removal of the alkali metal is more efficiently performed.

Mixing ratio The ratio of the vinyl chloride polymer-polyurethane coexisting reaction composition (a1) to the halogen-containing thermoplastic resin (A) is 0.1%.
It is necessary that the content be 1% by weight to 100% by weight, and the remainder is a halogen-containing polymer (a2) other than the above, such as a normal vinyl chloride polymer. When the proportion of the coexisting reaction composition (a1) is less than 0.1% by weight, the compatibility when the vinyl alcohol-based polymer (B) is blended becomes insufficient, and the moldability, the appearance and physical properties of the molded product are impaired.

The mixing ratio of the vinyl alcohol polymer (B) to 100 parts by weight of the halogen-containing thermoplastic resin (A) composed of the coexisting reaction composition (a1) or the other halogen-containing polymer (a2) is 0.1%. It is selected from the range of ~ 100 parts by weight. A more preferred range is 0.5 to 50 parts by weight.

If the amount of the vinyl alcohol-based polymer (B) is too small, the effect of improving the properties of the halogen-containing thermoplastic resin (A) is lost, and if the amount is too large, the intrinsic properties of the halogen-containing thermoplastic resin (A) are impaired.

Other additives In the present invention, in addition to the above components, if necessary,
Plasticizer, antioxidant, stabilizer, stabilizing aid, ultraviolet absorber, dye / pigment, filler, lubricant, antistatic agent, surfactant, chelating agent, reinforcing material, foaming agent, flame retardant, impact resistance improvement A known additive for a polyvinyl chloride resin, such as an agent, can be blended. Further, other thermoplastic resins can be blended as long as the spirit of the present invention is not impaired.

Blending order The vinyl chloride polymer-thermoplastic polyurethane coexisting reaction composition (a1), the other halogen-containing polymer (a2), the vinyl alcohol polymer (B), and other additives can be added simultaneously or optionally. And then subjected to melt molding.

Melt molding As the melt molding method, a calendar molding method, an extrusion molding method, an injection molding method, a blow molding method and the like can be adopted.

Function and Effect of the Invention In the present invention, at the time of melt molding a blend of a halogen-containing thermoplastic resin (A) and a vinyl alcohol-based polymer (B), at least a part of the halogen-containing thermoplastic resin (A) is used. Since the specific vinyl chloride polymer-polyurethane coexisting reaction composition (a1) was used, the lack of compatibility between the vinyl alcohol polymer (B) and the halogen-containing thermoplastic resin (A) was effectively improved, and the molding thereof was performed. The effect of improving the properties and physical properties of the halogen-containing thermoplastic resin (A) by the vinyl alcohol-based polymer (B) is remarkably improved.

Therefore, in the case of calender molding, plate-out is not recognized, and in the case of extrusion molding, long-run molding is possible, and coloring of the obtained molded product is effectively suppressed, and the appearance and physical properties are favorable. .

EXAMPLES Next, the production method of the present invention will be further described with reference to examples.

—Preparation of Materials— The following materials were prepared as the halogen-containing thermoplastic resin (A) and the vinyl alcohol-based polymer (B).

Halogen-containing thermoplastic resin (A) <Coexisting reaction composition (a1)> (a1-1) 1 part by weight of calcium stearate and 1 part by weight of zinc stearate are blended in advance and mixed in a Henschel mixer.
Polyvinyl chloride powder with a polymerization degree of 1100 mixed with high-speed stirring for 1 minute
100 parts by weight of 100 parts by weight of a polyester polyol having a molecular weight of 2000 obtained by condensation of adipic acid with 1,4-butanediol / neopentyl glycol (molar ratio: 9/1)
The mixture was added while being heated to 0 ° C, and stirred and mixed at 100 ° C for 10 minutes, and then 9 parts by weight of tolylene diisocyanate was added.
The temperature was raised to 110 ° C., and stirring and mixing were continued for 1 hour to carry out a urethanization reaction.

The reaction product was cooled to room temperature to obtain a powdered polyvinyl chloride-polyurethane coexisting reaction composition. The polyurethane content was 52%.

(A1-2) 100 parts by weight of polyvinyl chloride powder having a polymerization degree of 1100, 1 part by weight of calcium stearate, 1 part by weight of zinc stearate, adipic acid and 1,4-butanediol / neopentyl glycol (9/1 molar ratio) Using 40 parts by weight of the polyester polyol obtained by condensation with 5 parts by weight of diphenylmethane diisocyanate, a powdery polyvinyl chloride-polyurethane coexisting reaction composition was obtained according to the above (a1-1). The polyurethane content was 30%.

(A1-3) 100 parts by weight of polyvinyl chloride powder having a degree of polymerization of 1100, 1 part by weight of calcium stearate, 1 part by weight of zinc stearate, and a polyester having a molecular weight of 2,000 obtained by condensation of sebacic acid with 1,6-hexanediol Using 140 parts by weight of polyol and 12 parts by weight of tolylene diisocyanate,
A powdery polyvinyl chloride-polyurethane coexisting reaction composition was obtained according to the above (a1-1). Polyurethane content is
60%.

<A halogen-containing polymer other than the above (a2)> (a2-1) Polyvinyl chloride having a degree of polymerization of 800 (a2-2) Vinylidene chloride-methyl acrylate copolymer having a methyl acrylate content of 7 mol% Vinyl alcohol-based polymer Combined (B) (B-1) Ethylene content of 44 mol%, degree of saponification of vinyl acetate moiety 9
9.5 mol%, melting point 167 ℃, ash content 6ppm, sodium metal content
2.7 ppm saponified ethylene-vinyl acetate copolymer (B-2) Ethylene content 55 mol%, saponification degree of vinyl acetate portion 7
9.0 mol%, melting point 111 ° C., ash content 15 ppm, sodium metal content 4.0 ppm, saponified ethylene-vinyl acetate copolymer (B-3) dodecene-1 content 5.5 mol%, saponification degree of vinyl acetate portion 99.3 mol%, Saponified dodecene-1 / vinyl acetate copolymer having a melting point of 187 ° C, an ash content of 215 ppm and a sodium metal content of 140 ppm (B-4) Degree of polymerization 500, saponification degree 70.0 mol%, melting point 170 ° C, ash content 12
Polyvinyl alcohol having 0 ppm and a sodium metal content of 70 ppm -Blending composition and molding conditions- After premixing the above materials at the ratios shown in Table 1, extrusion molding was carried out under the following conditions. Hereinafter, "parts" refers to parts by weight.

When the halogen-containing polymer (a2) was polyvinyl chloride, the compounding recipe and extrusion molding conditions were set as follows.

<Formulation formulation> Coexisting reaction composition (a1) Notation Polyvinyl chloride (a2) Notation (Total amount of (a1) and (a2) is 100 parts) Vinyl alcohol polymer (B) Notation Epoxidized soybean oil 3 parts Stair 0.5 parts of calcium phosphate 0.5 parts of zinc stearate 0.2 parts of stearoylbenzoylmethane <Extrusion molding condition> Extruder: 30 mm diameter extruder T die: 200 mm width, sheet thickness 0.3 mm Screw: Full flight constant pitch, L / D = 20, compression ratio
3.0, rotation speed 30rpm Temperature: C1130 ℃, C2 175 ℃, C3 180 ℃, H 170 ℃,
D 180 ° C Screen: 80 mesh x 2 Take-up rolls: 85-90 ° C Also, when the halogen-containing polymer (a2) is a vinylidene chloride-methyl acrylate copolymer, the formulation and extrusion conditions are as follows. Set to.

<Blending formulation> Coexisting reaction composition (a1) Notation Vinylidene chloride-methyl acrylate copolymer (a2) notation (Total amount of (a1) and (a2) is 100 parts) Vinyl alcohol polymer (B) Notation Epoxy Soybean oil 3 parts Calcium stearate 0.5 parts Zinc stearate 0.5 parts Stearoyl benzoyl methane 0.2 parts <Extrusion molding conditions> Extruder: 40 mm diameter extruder Screw: L / D = 23, compression ratio 3.2, rotation speed 30 rpm (other conditions) The conditions and results are shown in Table 1.

The measurement and evaluation were performed as follows.

Extrusion moldability was determined by the presence or absence of abnormalities such as drawdown and torque change during continuous molding for 8 hours.

The appearance of the molded product is based on the molded product after continuous molding for 8 hours.
Judgment was made based on the presence or absence of coloring, fish eyes, vertical stripes, and the like.

The total light transmittance was measured according to JIS K6745 (1 mm thick sheet).

The impact strength was measured by measuring the Izod impact strength according to JIS K7110. “Non-destructive” in the table indicates that all of the tests were non-destructive for 10 tests, and “>74,>70,>
“61,> 56” indicates that the minimum values in the case of 10 tests are 74, 70, 61, and 56, respectively.

The discharge half-life was measured using an honest meter.
When the halogen-containing thermoplastic resin (A) is used alone, the resin (A) is (a1-1), (a1-2), (a1-3), (a2-1),
Regardless of (a2-2), or when these are used together in an arbitrary ratio, the discharge half-life becomes Δ.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) C08L 27/02-27/20 C08L 29/04 C08L 75/04-75/16

Claims (4)

(57) [Claims] 1. A vinyl chloride polymer-polyurethane coexisting reaction composition (a1) having a polyurethane content of 10 to 90% by weight obtained by reacting a polyol and a polyisocyanate in the presence of a vinyl chloride polymer. 0.1 to 100 parts by weight of a vinyl alcohol-based polymer (B) that can be melt-molded in 100 parts by weight of a halogen-containing thermoplastic resin (A) consisting of 0.1% by weight and another 0 to 99.9% by weight of a halogen-containing polymer (a2) A method for producing a halogen-containing thermoplastic resin-based molded product, comprising blending parts and melt-molding. 2. The low-ash / low-alkali metal vinyl alcohol polymer having a melting temperature of 200 ° C. or less, an ash content of 300 ppm or less, and an alkali metal content of 200 ppm or less. Manufacturing method. 3. A saponified ethylene-vinyl acetate copolymer wherein the vinyl alcohol polymer (B) has an ethylene content of 20 to 75 mol% and a saponification degree of the vinyl acetate portion of 50 mol% or more. Manufacturing method. 4. A saponified ethylene-vinyl acetate copolymer having an ethylene content of 20 to 75 mol% and a degree of saponification of the vinyl acetate portion of 50 mol% or more has a melting temperature of 200 ° C. or less and an ash content of 300 ppm.
4. The process according to claim 3, wherein the saponified product is a low ash / low alkali metal ethylene-vinyl acetate copolymer having an alkali metal content of 200 ppm or less.