JP2008133372A - Polyester-based plasticizer, and vinyl chloride-based resin composition containing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a polyester-based plasticizer with high oil resistance, and to provide a vinyl chloride-based resin composition containing the same. <P>SOLUTION: The polyester-based plasticizer is 500-10,000 mPa s in viscosity at 25°C, being produced from a 4-8C aliphatic dibasic acid and a dihydric alcohol, wherein the dihydric alcohol is a crude 1,2-butanediol containing at least acetoxyhydroxybutane or diacetoxybutane. In this plasticizer, the terminals are blocked with a hydroxy group and an acetate residue, wherein the terminal blocked rate for the acetate residue is 20-80%. The vinyl chloride-based resin composition contains 10-200 pts.wt. of the above plasticizer based on 100 pts.wt. of a vinyl chloride-based resin. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a polyester plasticizer and a vinyl chloride resin composition containing the same.

  Plasticizers can be added to various plastics, including vinyl chloride resins, to lower their melt viscosity and facilitate molding processability, and to provide plastics with performance such as flexibility, elasticity, and cold resistance. Is widely used to adapt to various uses of plastics.

  Monomeric plasticizers such as di-2-ethylhexyl phthalate and di-2-ethylhexyl adipate are common as plasticizers used for such purposes, but durability such as oil resistance and migration resistance Polyester plasticizers have been awarded for applications that require a large amount of water.

  Examples of polyester plasticizers include polyhydric alcohols such as ethylene glycol, 1,2-propanediol, 1,3-butanediol, and 1,4-butanediol, and polybasic acids such as phthalic acid, adipic acid, and sebacic acid. Is generally produced by terminal treatment with a monohydric alcohol in consideration of performance such as compatibility with plastic and plasticizing efficiency (see, for example, Patent Document 1) .) On the other hand, Patent Document 2 discloses a crude product containing acetoxy compounds such as acetoxyhydroxybutane and diacetoxybutane, which is a by-product during the production of 1,4-butanediol by reaction of butadiene and acetic acid as a polyhydric alcohol. By using 1,2-butanediol, a polyester plasticizer end-capped with acetic acid resulting from the condensation reaction can be obtained without the addition of a terminal treatment agent such as a monohydric alcohol or a monobasic acid. It is shown.

As described above, polyester plasticizers are used in applications where durability is required, especially oil resistance. However, in recent years, the level of demand for oil resistance has increased, and these conventional polyester-based plasticizers have been increasingly used. Responding to plasticizers is becoming difficult.
Japanese Patent Publication No. 63-10727 Japanese Patent Publication No. 63-10728

  The present invention has been made to improve the above-mentioned drawbacks of the prior art, and an object thereof is to provide a polyester plasticizer excellent in oil resistance and a vinyl chloride resin composition containing the same.

  As a result of intensive studies to solve the above problems, the present inventor is a polyester plasticizer produced from an aliphatic dibasic acid having 4 to 8 carbon atoms and a dihydric alcohol, and the dihydric alcohol is The present inventors have found that a polyester plasticizer which is crude 1,2-butanediol and has a specific end-capping structure gives a vinyl chloride resin composition having excellent oil resistance, thereby completing the present invention.

That is, the gist of the present invention is a polyester plasticizer produced from an aliphatic dibasic acid having 4 to 8 carbon atoms and a dihydric alcohol and having a viscosity at 25 ° C. of 500 to 10,000 mPa · s, Is a crude 1,2-butanediol containing at least acetoxyhydroxybutane or diacetoxybutane, and the end is blocked with a hydroxyl group and an acetate residue, and the endblocking rate with the acetate residue is 20 to 80% And a vinyl chloride resin composition containing 10 to 200 parts by weight of the polyester plasticizer per 100 parts by weight of the polyester plasticizer.

  According to the present invention, it is possible to provide a polyester plasticizer excellent in oil resistance and a vinyl chloride resin composition containing the same.

Hereinafter, the present invention will be described in more detail.
The polyester plasticizer of the present invention is a polyester plasticizer produced from an aliphatic dibasic acid having 4 to 8 carbon atoms and a dihydric alcohol and having a viscosity of 500 to 10,000 mPa · s at 25 ° C. The alcohol is a crude 1,2-butanediol containing at least acetoxyhydroxybutane or diacetoxybutane, and the end is blocked with a hydroxyl group and an acetate residue, and the endblocking rate with the acetate residue is 20 to 80 %.

  In the polyester plasticizer of the present invention, examples of the aliphatic dibasic acid having 4 to 8 carbon atoms include succinic acid, glutaric acid, adipic acid, azelaic acid, sebacic acid, and the like, one or more of them. Among them, adipic acid is particularly preferable.

  Further, as the dihydric alcohol, it is essential that it is a crude 1,2-butanediol containing at least acetoxyhydroxybutane or diacetoxybutane. As the crude 1,2-butanediol, butadiene and acetic acid are used. What is obtained as a by-product in the production of 1,4-butanediol by reaction is preferred. Specific examples of the crude 1,2-butanediol obtained as the by-product include, for example, about 65% by mass of 1,2-butanediol, about 5% by mass of acetoxyhydroxybutane, and about 30% by mass of diacetoxybutane. The crude 1,2-butanediol manufactured by Mitsubishi Chemical Corporation.

  Examples of the dihydric alcohol include, in addition to the crude 1,2-butanediol, 1,2-propylene glycol, 1,3-butanediol, 1,4-butanediol, 2-methyl-1,3- Propanediol, 2,2-dimethyl-1,3-propanediol, 3-methyl-1,5-pentanediol and the like may be used in combination, but these dihydric alcohols other than crude 1,2-butanediol Is preferably less than 50% by weight of the total dihydric alcohol, particularly preferably less than 30% by weight.

  The polyester plasticizer of the present invention needs to have a viscosity at 25 ° C. in the range of 500 to 10,000 mPa · s from the viewpoint of balance between oil resistance and other performance or workability, and at 25 ° C. The viscosity is preferably 1000 to 5000 mPa · s.

  In addition, the polyester plasticizer of the present invention has a terminal blocking rate of 20 to 20% determined by the following formula, from which the terminal is blocked with a hydroxyl group and an acetate ester residue, from the balance between compatibility and oil resistance. It is essential to be 80%. If the terminal blocking ratio is lower than 20%, the oil resistance tends to be improved, but the compatibility with the vinyl chloride resin is deteriorated and the polyester plasticizer tends to bleed on the resin surface, whereas it is higher than 80%. As a result, sufficient oil resistance cannot be obtained.

Terminal blocking ratio with acetic acid = [{A × 56/60} / {(A × 56/60) + B}] × 10
0 (%)
Here, A: mass (mg) of acetic acid per 1 g of polyester plasticizer generated by hydrolysis of polyester plasticizer, B: hydroxyl value (KOHmg / g)

  The polyester plasticizer of the present invention is prepared by a conventionally known method, for example, the aliphatic dibasic acid and dihydric alcohol in the presence of a catalyst, usually at a temperature of 180 to 240 ° C., preferably 200 to 230 ° C. The reaction is carried out with an esterification reaction while removing water produced by the reaction, and after the reaction has progressed to some extent, the system is depressurized and the excess dihydric alcohol is removed while gradually increasing the degree of vacuum. Manufactured. At that time, for example, the amount of the dihydric alcohol used is in the range of 1.2 to 3.0 times mol with respect to 1 mol of the aliphatic dibasic acid, and acetoxyhydroxybutane or diacetoxybutane contained in the dihydric alcohol. When the content ratio is 10 to 45 weights and / or the degree of vacuum at the end of the reaction is in the range of 200 to 5 torr, a polyester plasticizer having the above-mentioned end-capping ratio with acetic acid can be produced.

  The polyester plasticizer of the present invention is used for improving the workability of a plastic, imparting flexibility, etc., among them, for halogen-containing resins such as vinyl chloride resins, vinylidene chloride resins, chlorinated polyolefin resins, etc. It is preferably used as a plasticizer for a vinyl chloride resin, and is particularly suitable for constituting a vinyl chloride resin composition as a plasticizer for a vinyl chloride resin. Here, examples of the vinyl chloride resin include a homopolymer or copolymer of vinyl chloride, or a mixture thereof, and the production method thereof is not limited, and suspension polymerization, emulsion polymerization, bulk polymerization. Etc. can be used.

  In a particularly preferred vinyl chloride resin composition, the content as a plasticizer is 10 to 200 parts by weight, preferably 20 to 150 parts by weight of the polyester plasticizer of the present invention per 100 parts by weight of vinyl chloride resin. It is considered as a range. If the amount of the polyester plasticizer used is too small, the effect of improving the workability during the molding process will be insufficient. On the other hand, if it is too large, the polyester plasticizer will easily bleed on the surface of the vinyl chloride resin composition.

  The vinyl chloride resin composition has other plasticizers that are usually used without departing from the object of the present invention, such as dibutyl phthalate, di-2-ethylhexyl phthalate, diisononyl phthalate, Phthalic acid diester such as diisodecyl phthalate, adipic acid diester such as di-2-ethylhexyl adipate, diisononyl adipate, trimellitic triester such as tri-2-ethylhexyl trimellitic acid, phosphoric acid such as triphenyl phosphate Esters and epoxy plasticizers such as epoxidized soybean oil may be used in combination.

  In addition, the vinyl chloride resin composition includes compounding agents generally used for vinyl chloride resins including the above-mentioned combined use plasticizer within a range not impairing the object of the present invention, such as fillers, stabilizers, oxidation agents, and the like. An inhibitor, a flame retardant, an ultraviolet absorber, a colorant, and the like may be added as necessary.

  The vinyl chloride resin composition of the present invention contains a predetermined amount of a vinyl chloride resin, a plasticizer containing the polyester plasticizer of the present invention, and other additives, and a ribbon blender, Henschel mixer, Banbury. It can be obtained by stirring and kneading with a mixing / kneading machine such as a mixer, mill roll or extruder, and further with a molding machine such as a calendar, injection molding machine or extrusion molding machine, film, sheet, container, flooring, etc. The molded product.

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to the following examples unless it exceeds the gist.
<Preparation of polyester plasticizer>
Example 1-1
In a 1 L four-necked flask equipped with a stirrer, a thermometer and a condenser, 292 g of adipic acid, 311 g of crude 1,2-butanediol (composition: 1,2-butanediol 65% by mass, acetoxyhydroxybutane 30% by mass) , Diacetoxybutane (5% by mass), and heated with stirring to 220 ° C. The water generated during this time was continuously removed from the system. Next, 0.05 ml of tetraisopropyl titanate was added, the pressure was gradually reduced, and the water produced was continuously removed from the system. When the degree of vacuum reached 110 torr, the reaction was stopped when the viscosity reached 970 mPa · s at 25 ° C. measured by the following method.
<Viscosity>
The measurement was performed at 25 ° C. using an E-type viscometer manufactured by Tokyo Keiki Co., Ltd.

The obtained polyester-based plasticizer had a hydroxyl value determined by the following method of 113 KOHmg / g and an acid value of 0.57 KOHmg / g.
<Hydroxyl value / Acid value>
Quantification was performed according to JIS K0070.

Further, the terminal blocking ratio with acetic acid calculated by the following method was 28%.
<Terminal blocking ratio with acetic acid>
To 1 g of the obtained polyester plasticizer, 20 ml of ethanol, 1 ml of water and 1 g of calcium hydroxide were added and heated in a boiling state for 1 hour. After cooling, acetic acid was quantified by acid chromatography with hydrochloric acid, and the result was 47 mg per 1 g of the polyester plasticizer. From the amount of acetic acid and the hydroxyl value, the end-capping rate by acetic acid was calculated by the above formula.

Examples 2-1 to 4-1
The amount of crude 1,2-butanediol charged was changed as shown in Table 1, and in the same manner as in Example 1, polyester plasticizers of Examples 2-1 to 4-1 in Table 1 were obtained. Table 1 shows the viscosity, acid value, hydroxyl value, and end capping rate with acetic acid of the obtained polyester plasticizer.

Comparative Example 1-1
In a 1 L four-necked flask equipped with a stirrer, a thermometer, and a condenser tube, 292 g of adipic acid, crude 1,2-butanediol (composition: 1,2-butanediol 65% by mass, acetoxyhydroxybutane 30% by mass, 204 g of diacetoxybutane (5% by mass) was added and heated with stirring to a temperature of 220 ° C., then the degree of vacuum was gradually increased, and the pressure was finally reduced to 30 torr. The water generated during this time was continuously removed from the system. Next, instead of the cooling pipe, a Dean-Stark type water separator and a reflux condenser were attached, 102 g of 2-ethylhexanol and 0.05 ml of tetraisopropyl titanate were added, and 2-ethylhexanol was refluxed at 220 ° C. under reduced pressure. The reaction was carried out, and the reaction was continued until the acid value became 3 KOHmg / g or less. Thereafter, a cooling pipe was attached in place of the Dean-Stark type water separator and the reflux condenser, and the degree of vacuum was gradually increased, and finally, the excess 2-ethylhexanol was removed as a reduced pressure of less than 5 torr. Was reacted for 1 hour to obtain a polyester plasticizer.
The obtained polyester plasticizer whose end was blocked with 2-ethylhexanol had a hydroxyl value of 7 KOH mg / g, an acid value of 0.23 KOH mg / g, and a viscosity at 25 ° C. of 990 mPa · s.

Comparative Examples 2-1 to 4-1
The amount of crude 1,2-butanediol and 2-ethylhexanol charged was changed as shown in Table 1, and the same procedure as in Comparative Example 1 was carried out to obtain polyester plasticizers of Comparative Examples 2-1 to 4-1 in Table 1. . Table 1 shows the viscosity, acid value, and hydroxyl value of the obtained polyester plasticizer.

Comparative Example 5-1
A 1-L four-necked flask equipped with a stirrer, a thermometer, and a condenser was charged with 292 g of adipic acid and 360 g of 2-methyl-1,3-propanediol, and heated to 220 ° C. while stirring. The water generated during this time was continuously removed from the system. Subsequently, 0.05 ml of tetraisopropyl titanate was added and the pressure was gradually reduced, and subsequently generated water and 3-methyl-1,3-propanediol were continuously removed from the system. The degree of vacuum was finally less than 5 torr, and the reaction was stopped when the viscosity at 25 ° C. reached 2040 mPa · s.
The obtained polyester plasticizer having a hydroxyl group at the end had a hydroxyl value of 166 KOHmg / g and an acid value of 0.21 KOHmg / g.

Comparative Example 6-1
The amount of crude 1,2-butanediol charged was changed as shown in Table 1, and the same as in Example 1, except that the reduced pressure at the end of the reaction was less than 5 torr and the reduced pressure was maintained for 30 minutes. A polyester plasticizer of Comparative Example 6-1 was obtained. Table 1 shows the viscosity, acid value, hydroxyl value, and end capping rate with acetic acid of the obtained polyester plasticizer.

<Preparation of vinyl chloride resin composition>
Examples 1-2 to 4-2 and Comparative Examples 1-2 to 6-2
50 parts by weight of the polyester plasticizer obtained in Examples 1-1 to 4-1 and Comparative Examples 1-1 to 6-1 to 100 parts by weight of vinyl chloride resin (“MT1300D” manufactured by Vitec) And 3 parts by weight of a stabilizer (“Mark RUP-106” manufactured by Adeka Argus Chemical Co., Ltd.) were blended to prepare a vinyl chloride resin composition. Each vinyl chloride resin composition was sufficiently mixed with a mill roll set at 170 ° C., and then pressed to a thickness of 1 mm and 0.1 mm to obtain a sheet. (Vinyl chloride resin compositions prepared using the polyester plasticizers obtained in Examples 1-1 to 4-1 and Comparative Examples 1-1 to 6-1 are respectively Examples 1-2 to 4-2. And Comparative Examples 1-2 to 6-2.)

About each obtained sheet | seat, the oil resistance and the bleeding state of a plasticizer were evaluated with the following method. The results are summarized in Table 2.
<Oil resistance>
(1) Mixed solvent extraction test: A test piece having a diameter of 5 cm punched from a 1 mm thick press sheet was immersed in about 500 ml of a mixed solvent (isooctane / toluene = 70/30% by volume) at 23 ° C. for 24 hours, and then 80 It dried for 4 hours with the dryer of degreeC. The amount of plasticizer loss (%) was calculated from the weight change before and after the test according to the following formula.
Loss of plasticizer = [(mass of test piece before test−mass of test piece after test) / plasticizer mass in test piece before test] × 100 (%)
(2) Heptane dissolution test: Using a press sheet with a thickness of 0.1 mm, a standard test for equipment standards and containers and packaging of food additives, etc. (Ministry of Health and Welfare Notification No. 370, 1959) Implemented by law.
<Bleed state>
A press sheet having a thickness of 1 mm was left in a thermostatic chamber at 23 ° C. and a relative humidity of 50% for 2 weeks, and then the presence or absence of bleeding of plasticizer on the sheet surface was visually observed.

Claims (6)

  A polyester plasticizer produced from an aliphatic dibasic acid having 4 to 8 carbon atoms and a dihydric alcohol and having a viscosity at 25 ° C. of 500 to 10,000 mPa · s, wherein the dihydric alcohol is acetoxyhydroxybutane or diacetoxybutane Polyester characterized by comprising crude 1,2-butanediol containing at least an amino acid, the terminal is blocked with a hydroxyl group and an acetate residue, and the terminal blocking rate with the acetate residue is 20 to 80% Plasticizer.   The polyester plasticizer according to claim 1, wherein the aliphatic dibasic acid is adipic acid.   The polyester plasticizer according to claim 1 or 2, wherein the crude 1,2-butanediol is a by-product during the production of 1,4-butanediol.   The polyester plasticizer according to any one of claims 1 to 3, comprising a dihydric alcohol other than crude 1,2-butanediol as the dihydric alcohol.   The polyester plasticizer according to claim 4, wherein the content of dihydric alcohol other than crude 1,2-butanediol is less than 50 mass% of the entire dihydric alcohol.   A vinyl chloride resin composition comprising 10 to 200 parts by weight of the polyester plasticizer according to any one of claims 1 to 5 per 100 parts by weight of a vinyl chloride resin.