JPH0720925B2 - Complex ester and plasticizer composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention can be used for plasticizing vinyl resin or vinyl chloride resin, such as those used as agricultural greenhouses for covering crops or for keeping greenhouses warm. It relates to a composition. More specifically, the present invention provides the general formula [I] RO (COXCOOCH ₂ CH ₂ SCH ₂ CH ₂ O) nCOYCOOR [I] where R is a monofunctional alcohol residue having 4 to 9 carbon atoms, X and Y represents the same or different linear saturated or unsaturated aliphatic dicarboxylic acid residue or aromatic dicarboxylic acid residue having 3 to 8 carbon atoms, and n is an integer of 1 or 2.] The present invention relates to a plasticizer composition in which volatility is eliminated, cold resistance is enhanced, and long-term weather resistance is achieved by using a complex ester having the same or different groups. This plasticizer can be used for plasticizing vinyl resin or vinyl chloride resin.

[Conventional technology]

A lot of literatures have already been reported on the technology for producing complex esters, patents have been filed, and low-viscosity polyesters are marketed. The inventor of the present application has conducted various studies for the purpose of achieving an excellent production technique for a complex ester, and a method of carrying out transesterification reaction between a large excess of dibasic acid diester and diol (JP-A-60-45547). , And a method for conducting a transesterification reaction between an ester alcohol and a diester (JP-A-61-76442). In addition, the catalyst for esterification reaction was studied, and polyol polytitanic acid ester or acid, or polytitanic acid, or polytitanic acid having polyol polytitanic acid structure was used as an excellent catalyst for esterification and transesterification reaction. I was found to be
60-219140, Japanese Patent Application 60-280220, Japanese Patent Application 61-132618).

On the other hand, a method for producing various complex esters using a titanium catalyst or polytitanate ester is described in U.S. Pat.Nos. 2,628,974, 2703811, 3194664, among which the complex ester is produced. 2 moles of dibasic acid and 2 moles of monofunctional alcohol or a 10 percent excess are used per mole of stoichiometric diol. Furthermore, it is described in this patent that thiodiglycol can be used as a diol component, but there is no description of a specific compound.

[Problems to be Solved by the Present Invention]

The composite ester of the invention filed by the inventor of the present invention exhibits excellent plasticity with respect to vinyl chloride resin, but the invention of the present application is superior to that in general and has excellent cold resistance, long-term weather resistance, low volatility, and plasticity. Was completed from the need to obtain a complex ester plasticizer composition having

[Means for solving problems]

A thiodiglycol was used to produce a complex ester or a heterogeneous complex ester according to the same method as described above for producing the complex ester of the invention filed by the present inventor, and using this as a plasticizer, The performance was evaluated and it was found that the performance was better than expected.

It is particularly necessary that this complex ester be produced according to the production technique of the invention for which the above-mentioned inventors of the present application have applied. That is, the ester mixture obtained by the conventional method for producing a complex ester using a stoichiometric amount of a dicarboxylic acid, a diol, and a monofunctional alcohol does not have half the target proportion of the complex ester.

On the other hand, the complex ester and the heterogeneous complex ester are disclosed by the inventors of the present invention as described above (JP-A-60-45547, JP-A-61-7).
6442) or an unpublished (Japanese Patent Application No. 61-75233) patent application, a method of partially utilizing these methods, and a direct esterification method using the above polytitanic acid catalyst. When it is produced, the proportion of complex esters in the produced ester mixture is high, and therefore its viscosity is low, and when it is used as a plasticizer, dioctyl phthalate (hereinafter referred to as DOP) has the best plasticity and volatility on the market.
It is possible to obtain a very excellent plasticizer having more excellent plasticity and volatility resistance than that of (abbreviated) and less coloring even when used for a long time.

That is, thiodiglycol is used as a diol component, dicarboxylic acid is used in a large excess of 2 mol or more, preferably 3 to 4 mol per 1 mol of thiodiglycol, and a monofunctional alcohol corresponding thereto is used. The above object of the present application can be achieved.

[Method for producing complex ester]

As one method for producing the complex ester used as the plasticizer of the present invention, a transesterification method with thiodiglycol using a large excess of dicarboxylic acid diester is performed to obtain the complex ester of the present invention. The technology of Japanese Patent Laid-Open No. 60-45547 is used.

As another method of the complex ester of the present invention, a dehydration esterification reaction is carried out by using 3 or 4 mol of dicarboxylic acid, 5 or 7 mol or more of monofunctional alcohol to 1 mol of thiodiglycol. The products of the formula below (ester alcohols and diesters) are obtained.

HOCH ₂ CH ₂ SCH ₂ CH ₂ OH + (m + 1) HOCOXCOOH + (2m + 1)
ROH → ROCOXCOOCH ₂ CH ₂ SCH ₂ CH ₂ OH + mROCOXCOOR where R and X are the residues of alcohol and acid, respectively, and m is 2 or 3 molar amount depending on whether the number of moles of dicarboxylic acid used is 3 or 4.

ROCOXCOOCH ₂ CH ₂ SCH ₂ CH is obtained by using polytitanic acid as a catalyst for the dehydration esterification reaction, and then heating the mixture under reduced pressure to carry out transesterification of the resulting ester alcohol and diester mixture for dealcoholization. _{2 The} desired product is obtained as a mixture of OCOXCOOR and m-1 mol of ROCOXCOOR. In the above method, except that thiodiglycol is used as the diol, JP-A-61-7 is used.
It uses the technology of 6442.

As another method for producing the complex ester of the present invention, a reaction between 1 mol of an anhydride of dicarboxylic acid and 1 mol of thiodiglycol is carried out in a dicarboxylic acid diester, and then an excess amount of a different dicarboxylic acid is added, and a necessary amount is further added. When the dehydration esterification reaction is carried out in the presence of the monofunctional alcohol, the product of the following formula is obtained.

X (CO) ₂ O + HO (CH ₂ ) ₂ S (CH ₂ ) ₂ OH → [HOCOXCOO (CH ₂ ) ₂ S (CH ₂ ) ₂ OH] [HOCOXCOO (CH ₂ ) ₂ S (CH ₂ ) ₂ OH] ＋ HOCOYCOOH + ROH → ROCOXCOOCH ₂ CH ₂ SCH ₂ CH ₂ OCOYCOOR ＋ mROCOOYCOOR (at the same time HOCOXCOOCH ₂ CH ₂ SCH ₂ CH ₂ OH ＋ ROCOYCOOR → ROCOXCOOCH ₂ CH ₂ SCH ₂ CH ₂ OCOYCOOR) The production technique of heterogeneous complex ester of 1) is utilized. Here, R, X, and Y respectively represent the residues of monofunctional alcohol, dicarboxylic acid anhydride, and dicarboxylic acid.

Further, as another method for producing the complex ester of the present invention, polytitanic acid is mainly used as a catalyst in the direct esterification method, and a reaction is started by adding a large excess of 3 to 4 mol of dicarboxylic acid to 1 mol of thiodiglycol. Then, a monofunctional alcohol is added and a dehydration esterification reaction is carried out to obtain the desired product via the intermediate of the following formula.

HOCH ₂ CH ₂ SCH ₂ CH ₂ OH + (m + 2) HOCOXCOOH → intermediate = HOCOXCOOCH ₂ CH ₂ SCH ₂ CH ₂ OCOXCOOH + mHOCOXCOOH → [+ ROH] → complex ester [I] Use of polytitanic acids as a catalyst for this dehydration esterification reaction Although preferred, the use of polytitanic acids not only accelerates dehydration esterification, but also has the advantage that very low acid value esters can be obtained and thus highly pure esters can be obtained.

Regarding the number of moles of the monofunctional alcohol used, it is generally common to use an excess amount with respect to the acid to increase the reaction rate. Although the above-mentioned US patent describes the use of an excess amount of 10%, the above-mentioned ROCOXCOOCH is said to be used in excess and particularly when a titanium-based catalyst is used to carry out the esterification reaction at a high temperature for a long time. An ester alcohol corresponding to ₂ CH ₂ SCH ₂ CH ₂ OH is produced. It is considered that a small amount of this ester alcohol is always by-produced when the esterification reaction is carried out in the presence of the above-mentioned three components. Therefore, in order to prevent the by-production of the ester alcohol, a dehydration esterification reaction is carried out and then the reaction is conducted under reduced pressure. It is necessary to heat and stir to remove the volatile monofunctional alcohol. It is considered that such a reaction for removing the by-product ester alcohol is in accordance with the method for producing the complex ester described above, and based on such an idea, the treatment after the dehydration esterification reaction is performed by the above-mentioned inventors. Can also be considered as utilization of the technology applied for by The amount of the monofunctional alcohol used can be reduced particularly by using solid polytitanic acid, and it is also adopted in a method of increasing the reaction rate by partial addition of the monofunctional alcohol.

Use more than 2 mol and at least 0.3 mol excess of acid anhydride with thiodiglycol when producing bis compound ROCOXCOOCH ₂ CH ₂ SCH ₂ CH ₂ OCOYCOOR using dicarboxylic acid anhydride When the reaction is carried out in this way, the reaction between the diol and the anhydride can be quantitatively carried out, and a complex ester can be produced in a high yield according to such a method.

The dicarboxylic acids used in these reactions are mainly adipic acid, maleic acid, phthalic acid, and their anhydrides, but malonic acid, succinic acid, glutaric acid, suberic acid or dihydrophthalic acid, and tetrahydrophthalic acid. It may be an acid. However, in the case of a heterogeneous complex ester, at least one of them must be an acid anhydride.

The most commonly used monofunctional alcohols are economically cheap, but butanol or octanol is selected, but alcohols having a straight chain or a side chain having 4 to 9 carbon atoms are used. Is preferably hexyl alcohol having 6 carbon atoms.

The various composite esters and heterogeneous composite esters produced in this manner can be effectively used as a plasticizer for resins such as polyvinyl chloride. That is, specifically shown in the examples, but when the plasticizing efficiency is measured using 50 parts or 80 parts of a plasticizer per 100 parts of resin, both are less than dioctyl phthalate DOP, which receives the best evaluation in the market. Dioctyl adipate, a plasticizer with excellent plasticity that shows the same effect as the amount used, even if left for a long time.
It has excellent compatibility without bleeding phenomenon that leaches to the surface like DOA, and it has low volatility especially corresponding to its molecular weight, and when heated for a long time, DOP and DOA volatilize and disappear, resulting in film or sheet The hardness increases and becomes harder, but with the complex esters found here, 100
It has the excellent feature that it hardly volatilizes even if it is heated for 7 weeks or more and retains the same hardness as the original. Furthermore, what is of interest is that it also has very good cold resistance. The flexible temperature measured using the
It has been found to have good performance in the range of ℃ to −32.2 ℃.

Examples are shown below, but the combination of dicarboxylic acid, thiodiglycol and monoalcohol is not limited to the description of the examples.

Example 1 Thiodiethylene glycol butyl adipate butyl maleate Maleic anhydride 39.2 g (0.4 mol), thiodiethylene glycol 48.8 g (0.4 mol) and dibutyl adipate 40 g
(0.15 mol) was placed in a dehydration esterification reactor to carry out a reaction between maleic anhydride and thiodiethylene glycol as a preliminary reaction. Dibutyl adipate is a solvent that allows the reaction to be carried out uniformly and the anhydride to react normally. If nothing is added, the acid anhydride will remain 100% unreacted. Stir at 60 ℃ to react, and measure the% anhydride, the% anhydride is 4.5
It decreased to 3.5% after hours and 1.2% after 6.5 hours.

For the mol% of anhydride, take a small sample in acetone, add 1 ml of it to 3 ml of 10% pyridine water, leave it for 10 minutes to make the anhydride acid, and then titrate with 1 / 20N alkali to obtain Aml. Obtained. Similarly, 1 ml of the sample was added to 3 ml of a 1: 1 mixture of toluene-aniline, left for 15 minutes to change the acid anhydride to the acid anilide, and then titrated in the same manner to obtain Bml. (AB) / B means the mol% of the anhydride in the acid. In the following examples, the anhydride was measured by this method to carry out the reaction sufficiently. It should be noted that the acid anhydride% seems to temporarily drop in a system that does not contain esters such as dibutyl adipate (DBA), but it will increase again to reach equilibrium at a value of 10 to 20% and 100% reaction of the acid anhydride will occur. Can not.

Then add 175.2 g (1.2 mol) of adipic acid to the reaction system,
As a catalyst, 0.8 g of polytitanic acid having a polyol polytitanic acid structure described separately was added. Butanol 177.6g (2.
4 mol) was weighed and 0.4 mol of it was added to start the reaction, and the dehydration esterification reaction was carried out while separating a small amount of water distilled together with a small amount of azeotropic auxiliary agent toluene with a separator. At first, water was distilled out from the reactor at 160 ℃, but the temperature gradually increased and butanol was added according to the ratio of water to be dehydrated while maintaining the temperature of 180-195 ℃. When 42 ml of water was discharged, 30 g (0.4 mol) of excess butanol was added to proceed the esterification, and the acid value of the reaction solution was 1.2 after 2 hours, 0.5 after 4 hours, and 0.3 after 7 hours. After the reaction, the mixture was stirred under reduced pressure of 25 mmHg at 180 ° C for 1 hour to remove excess butanol and butanol produced by the transesterification reaction, then cooled to 85 ° C, and water 3 ml
Was added and stirred again for 1 hour, 10 g of activated clay was added and the mixture was filtered to remove the catalyst. Then washed with alkaline water containing 0.5 g of caustic soda and hot water to adjust the acid value to 0.03, and then distilled 18
1 g of DBA was recovered and 121 g of thiodiethylene glycol butyl adipate butyl maleate was obtained as a residual liquid. The viscosity at 21 ° C. was 80.5 centipoise. To 100 parts of a polyvinyl chloride resin having a degree of polymerization of 1050, 2 parts of dibutyltin maleate and 0.5 part of dibutyltin malcaptide and 50 parts or 80 parts of the above plasticizer are added,
Knead for 3 minutes in a roll kneader at 0-165 ℃, then 170-175
A 1 mm sheet was prepared by carrying out a preheating for 3 minutes under a pressure of 100 atm at a temperature of 1 ° C. for 1 minute. The surface hardness of the 50PHR and 80PHR sheets respectively was measured by leaving them at 21 ° C for 48 hours.
The average of the distance from the reference line made by connecting the values of 50 PHR and 80 PHR measured using was drawn parallel lines to the reference line and the amount of the plasticizer showing the same hardness as the hardness of DOP50PHR was obtained. . This value is described below as plasticization efficiency. Its value is
A value of 40 was shown, and when 40 parts were used with respect to 100 parts of polyvinyl chloride, the hardness was equivalent to 50 parts of DOP, and it was proved that it was a very excellent plasticizer. The results of liquid chromatography analysis show that n = 1,2,3,4 is expected to be a mixture of several complex esters with a compound considered to be thiodiethylene glycol bisbutyl adipate or bisbutyl maleate in addition to the expected oligomers. Is. These had a boiling point of 260 ° C or higher under a reduced pressure of 0.1 mm and were difficult to purify by distillation. The heating test of the PVC sheet showed little coloration, and the weight loss on heating was very slight, and even after heating at 100 ° C for 7 weeks, 50P
Both HR and 80PHR maintain almost the same surface hardness as at the beginning. 50
The flexible temperature measured using the PHR sheet was -31.9 ° C, and the 50PHR DOP sheet measured as a control was -26.7 ° C.

The polytitanic acid catalyst used was 1 mol of tetrabutoxytitanium added to a solution of 3 mol of 2 ethylhexanol and 1/4 mol of pentaerythritol, heated and stirred at 180-195 ° C for 6 hours to remove 4 mol of butanol and then 1.5 mol. Water is added again and the mixture is heated and stirred at 180-195 ° C., and the 2-ethylhexanol produced under reduced pressure is distilled to obtain polytitanic acid having a polyol polytitanic acid structure.
It was created by activating by heating and stirring for 1 hour.

Example 2 Thiodiethylene glycol octyl adipate octyl maleate A procedure similar to that of Example 1 was followed, except that 2 ethylhexanol was used in place of butanol to prepare the above compound. A mixture of 39.2 g (0.4 mol) of maleic anhydride, 48.8 g (0.4 mol) of thiodiethylene glycol and 40 g of dioctyl adipate (DOA) was reacted by stirring at 70 ° C, and the anhydride was reduced to 2.5% after 3.5 hours. After 4 hours, 175.2 g (1.2 mol) of adipic acid was added to start the dehydration esterification reaction in the presence of a small amount of toluene. Reaction temperature 195-205 ℃
The reaction was carried out by adding 156 g (1.2 mol) of 2-ethylhexanol and an excess of 52 g while maintaining the above. The progress of dehydration esterification reaction is rapid and the acid value after 2 hours is 1.0, 4
The acid value after 0.1 hour was 0.11, and the acid value after 5 hours was 0.03.
After completion of the reaction, the mixture was heated and stirred at 180 ° C. under reduced pressure of 3 mmHg for 1 hour to recover excess octanol and 2-ethylhexanol produced by the transesterification reaction, and then 3 ml of water was added at 85 ° C. and the mixture was stirred and filtered with activated clay. The catalyst residue was removed, and the mixture was washed with a small amount of alkali and hot water to obtain an ester mixture having a low acid value. 356 g of DOA was collected at 160-180 ° C. under reduced pressure of 0.3 mmHg to obtain 172 g of thiodiethylene glycol octyl adipate octyl maleate as a residual liquid. The viscosity at 21 ℃ is 143 centipoise, the plasticization efficiency when used as a plasticizer is 45, it has a plasticity superior to DOP, it has low volatility, and the hardness of the sheet hardly changes even when heated at 100 ℃ for 7 weeks. Was also few.

The soft temperature measured using a 50PHR sheet was -29 ° C.

Example 3 thiodiethylene glycol bis2-ethylhexyl adipate adipic acid 233.6 g (1.6 mol), thiodiethylene glycol 48.8 g (0.4 mol), 2-ethylhexanol 208 g
0.8 g of polytitanic acid catalyst was added to the mixture (1.6 mol) to start the dehydration esterification reaction. Then add 195-205 while adding 104 g 2-ethylhexanol and 58 g excess.
The dehydration esterification reaction was carried out at ° C. The acid value after 4 hours is 1.
The acid value decreased to 0.03 after 3, 5.5 hours. 3m according to the usual method
After heating and stirring at 180-190 ℃ for 1 hour at mHg to collect excess octanol and 2-ethylhexanol produced by the transesterification reaction, it was stirred at 85 ℃ for 3 hours with 3 ml of water and the catalyst was filtered with activated clay. It was removed and washed with water containing a very small amount of alkali and hot water to obtain an ester mixture. Then 0.3m
DOA (317 g) was distilled under reduced pressure of mHg at 150 to 165 ° C. to obtain 182 g of thiodiethylene glycol bis-2-ethylhexyl adipate as a residual liquid. The viscosity at 21 ° C is 122 centipoise and its plasticization efficiency is 44. From the peak of the liquid chromatograph, n = 1 is about 60% and n = 2,3,4 decreases in sequence, and a complex ester containing a very small amount of 4 It was a mixture. The volatilization loss after heating was small and even after heating at 100 ° C. for 7 weeks, it was almost slight and the hardness of the vinyl chloride sheet hardly changed. 50PHR
The flexible temperature measured using the sheet was −32.2 ° C., which showed excellent cold resistance.

Example 4 thiodiethylene glycol bisbutyl adipate adipic acid 292 g (2 mol), thiodiethylene glycol
61 g (0.5 mol), 74 g using 0.8 g of polytitanic acid catalyst
A dehydration esterification reaction was started with (1 mol) butanol, and 148 g was sequentially added at 180-195 ° C according to the distillation rate of water.
(2 mol) and an excess amount of 40 g of butanol were added and reacted. Acid value is 22.2 after 6 hours and 4.2, 1 after 9 hours
It was 0.2 after 2 hours and 0.1 after 13 hours. After heating at 180 ° C under a reduced pressure of 25 mmHg to prevent DBA from distilling, butanol excess and butanol produced by transesterification were distilled, 3 ml of water was added, and the mixture was stirred at 85 ° C and filtered with activated clay to filter the catalyst. I removed it. It is washed with water containing a slight amount of alkali and hot water, distilled under reduced pressure, and 117-120 ℃ / 0.3mmHg DBA
Was removed, and 170 g of thiodiethylene glycol bisbutyl adipate was obtained as a residual liquid. Viscosity at 21 ° C is 92
Its plasticization efficiency was 42 in centipoise, showing excellent plasticity and low volatility, and the hardness of the sheet did not become large even in the heating test at 100 ° C. for 7 weeks.

Example 5 Thiodiethylene glycol bishexyl adipate 234 g (1.6 mol) adipic acid, 49 g (0.4 mol) thiodiethylene glycol and 82 g (0.8 mol) n-hexanol
0.8 g of a polytitanic acid catalyst was added to the mixture to start the dehydration esterification reaction using a small amount of toluene, and the temperature was kept at 185 to 200 ° C. The remaining 163 g of hexanol and an excess of 45 g were added and the reaction was carried out. Acid value is 7.5 after 2 hours, 0.1 after 3 hours, 3.
The value was 0.03 after 5 hours, and the esterification reaction was completed extremely rapidly. After heating for 1 hour at 180 ℃ / 3mmHg to remove hexanol, decatalysis is carried out in accordance with the usual method, and after filtering and washing with water, dihexyl adipate (DHA) 150-157 ℃ / 0.3
282 g of mmHg was distilled off to obtain 165 g of thiodiethylene glycol bishexyl adipate. The viscosity at 21 ° C was 92 centipoise, the plasticity efficiency was 40, and the plasticity was excellent. The volatility was low, the weight loss was small after heating, and the hardness hardly increased.

Example 6 Thiodiethylene glycol bis 2-ethylhexyl maleate 148 g (1.5 mol) of maleic anhydride and 73.2 g (0.6 mol) of thiodiethylene glycol, 2 ethylhexyl alcohol
When 39 g (0.3 mol) was added and heated and stirred at 70 ° C to react the anhydride, the amount of the anhydride was 3.1% after 1 hour and after 2.5 hours.
It decreased to 0.5%. 2 Ethylhexanol 156g and 0.8g
The reaction was started by adding the polytitanic acid catalyst of 1), and the dehydration esterification reaction was carried out at 195-205 ° C. while adding the remaining 195 g of octanol and an excess of 15 g. The acid value after 3 hours is 3.1, 7
It was 1.6 after hours and 0.8 after 9 hours. 180 mm under reduced pressure of 3 mmHg
After removing octanol at ℃ and removing the catalyst by a conventional method and washing with water, it was distilled to obtain thiodiethylene glycol bis 2-ethylhexyl maleate as a residual liquid of dibutyl maleate.
Viscosity at 21 ℃ is 139 centipoise and plasticization efficiency is 43
In the heating test at 100 ℃ for 7 weeks, the volatilization loss is approximately 1 / DOP.
Was 4.

Claims (4)

[Claims] 1. A general formula RO (COXCOOCH ₂ CH ₂ SCH ₂ CH ₂ O) nCOYCOOR wherein R is a monofunctional alcohol residue having 4 to 9 carbon atoms, and X and Y are the same or different. Represents a residue of a linear saturated or unsaturated aliphatic dicarboxylic acid or aromatic dicarboxylic acid having 8 carbon atoms, and n is an integer of 1 or 2.]. 2. A general formula RO (COXCOOCH ₂ CH ₂ SCH ₂ CH ₂ O) nCOYCOOR wherein R is a monofunctional alcohol residue having 4 to 9 carbon atoms, and X and Y are the same or different. A linear ester of 8 carbon atoms representing a residue of a saturated or unsaturated aliphatic dicarboxylic acid or aromatic dicarboxylic acid, n is an integer of 1 or 2], a plastic ester containing a complex ester or a mixture of two or more thereof. Agent composition. 3. The plasticizer composition according to claim 2, wherein R is a residue of a saturated aliphatic monohydric alcohol. 4. The plasticizer composition according to claim 2, which is a plasticizer for polyvinyl chloride.