JPH0132814B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing a neopentyl polyol fatty acid ester. In more detail,
The present invention relates to a method for efficiently producing a neopentyl polyol fatty acid ester of good quality by reacting a neopentyl polyol and a fatty acid ester in the presence of a base catalyst to perform alcoholysis.

Neopentyl type polyol fatty acid ester is
Because it has excellent heat resistance, lubricity, and surface activity, it is a useful compound that is widely used mainly in lubricating oils, metal processing oils, resin additives, and emulsifiers.

Conventionally, the method for producing neopentyl polyol fatty acid ester has followed the usual method for producing polyhydric alcohol fatty acid ester. (1) Neopentyl polyol and fatty acid are dehydrated and condensed in the presence of a trace amount of a base catalyst or an acid catalyst. Method and (2) Neopentyl polyol and a trace amount of fatty acid esters such as fatty acid methyl ester, fatty acid lower alkyl ester such as fatty acid ethyl ester, and fatty acid glyceride (0.1 to 1.0 weight based on the total amount of neopentyl polyol and fatty acid ester) %) is known, but each method has the following drawbacks.

That is, the first method requires the reaction to be carried out at a high temperature, usually 200 to 300°C, and therefore has the disadvantage that it consumes a large amount of energy and the product is likely to be colored. The second method uses alcohols that are relatively highly reactive, such as methanol, ethanol, propylene glycol, and glycerin, and have high solubility in fatty acid esters such as fatty acid lower alkyl esters and fatty acid glycerides, and have melting points. In the case of using alcohols with a low alcohol content, the alcoholysis reaction can be easily carried out in a liquid state at a relatively low temperature, and is an extremely useful method that has been widely practiced industrially. However, this method is not necessarily suitable as a method for producing neopentyl polyol fatty acid ester using alcohol such as neopentyl polyol. In the case of alcohols such as neopentyl polyols, which have extremely low solubility and reactivity with fatty acid esters, and also have a high melting point,
At a high temperature comparable to the first method (i.e. 200
This is because there is a problem in that it is difficult to obtain good results unless alcoholysis is performed (at a temperature exceeding .degree. C.) or in the presence of a special solvent. Therefore, it is difficult to say that the second method is particularly superior to the first method.

As a result of intensive studies to overcome the drawbacks of such conventional methods, the inventors of the present invention have developed a technique for producing neopentyl polyol fatty acid esters by alcoholysis by reacting neopentyl polyols with fatty acid esters. By heating and dissolving the raw material neopentyl polyol and fatty acid ester using a base catalyst without substantially using a solvent, the raw material neopentyl polyol and fatty acid ester exhibit compatibility, homogenize, and react, and easily produce the desired neopentyl polyol fatty acid ester. It has been found that the method can be manufactured economically and advantageously. The present invention has been made based on this knowledge.

That is, the present invention involves reacting a neopentyl polyol and a fatty acid ester to produce a neopentyl polyol fatty acid ester by alcoholysis, without using substantially any solvent, and reacting the raw material neopentyl polyol and fatty acid ester under heating. The present invention provides a method for producing a neopentyl polyol fatty acid ester, characterized in that the reaction is carried out using a base catalyst of 3 to 15% by weight based on the total amount of the neopentyl polyol fatty acid ester.

The neopentyl polyol used in the present invention has two or more hydroxyl groups in one molecule and has a partial skeleton. It is a polyhydric alcohol represented by neopentyl glycol, trimethylolethane, trimethylolpropane, trimethylolbutane, pentaerythritol, dipentaerythritol, and tripentaerythritol.

On the other hand, as the fatty acid ester, an ester of a fatty acid and a monohydric or trihydric alcohol is used. Specifically, methanol, ethanol, isopropanol, n-propanol, butanol,
ethylene glycol mono-lower alkyl ether,
Fatty acid esters of lower monohydric alcohols such as carbitol (also known as diethylene glycol mono-lower alkyl ether), fatty acid esters of lower dihydric alcohols such as ethylene glycol, propylene glycol, and butanediol, and fatty acid esters of lower trihydric alcohols such as glycerin. It can be cited as a representative example. Among them, glycerin fatty acid ester is in the form of glycerin trifatty acid ester and is used in plants and animals such as beef tallow, hydrogenated beef tallow, palm oil, palm kernel oil, coconut oil, olive oil, soybean oil, rapeseed oil, cottonseed oil, linseed oil, castor oil, lard, and fish oil. It is one of the most suitable and advantageous fatty acid esters for use in the method of the present invention because it can be obtained in large quantities and at low cost as a fatty oil. There are three types of glycerin fatty acid esters: glycerin monofatty acid esters (monoglycerides), glycerin difatty acid esters (diglycerides), and glycerin trifatty acid esters (triglycerides). Monoglycerides and diglycerides can also be used. The same applies to other lower trihydric alcohol fatty acid esters, and in the case of lower dihydric alcohol fatty acid esters, either monoesters or diesters can be used.

Although there are no particular restrictions on the fatty acid component constituting this fatty acid ester, fatty acids having about 5 to 24 carbon atoms are usually more preferably used in view of the intended use of the resulting neopentyl polyol fatty acid ester. This fatty acid component may be either a saturated fatty acid or an unsaturated fatty acid, and its carbon chain is not limited to a straight chain type, but may be a branched type. moreover,
A fatty acid having a substituent such as a hydroxyl group may also be used. Of course, these fatty acids are not limited to those derived from natural products, and may be synthetic fatty acids.

Typical examples of the above fatty acids include valeric acid, isovaleric acid, caproic acid, enanthic acid, caprylic acid,
pelargonic acid, capric acid, lauric acid, tridecanoic acid, 2-methyltetradecanoic acid, 5-methyltetradecanoic acid, 2,2-dimethyltetradecanoic acid, myristic acid, palmitic acid, margaric acid, stearic acid, oleic acid, linoleic acid, Examples include linolenic acid, ricinoleic acid, elaidic acid, erucic acid, arachidic acid, behenic acid, and lignoceric acid.

The above-mentioned neopentyl polyols and fatty acid esters do not necessarily need to be used alone, and two or more types of each can also be used in combination.

The ratio of neopentyl polyol and fatty acid ester used in the method of the present invention depends on the type and molecular weight of both raw materials, as well as the average degree of substitution of the desired neopentyl polyol fatty acid ester (i.e., the composition ratio of monoester, diester, triester, etc.) Although it varies depending on the product, the ratio of neopentyl polyol to fatty acid ester is usually 5 by weight.
It is carried out at a ratio of ~70:30-95, preferably 10-60:40-90, more preferably 15-55:45-85. Generally, as the proportion of neopentyl polyol used increases, the average degree of substitution of the obtained neopentyl polyol fatty acid ester tends to decrease.

The base catalyst used in the method of the present invention includes alkali metal carbonates such as lithium carbonate, sodium carbonate, and potassium carbonate, alkaline earth metal carbonates such as magnesium carbonate, calcium carbonate, and barium carbonate, lithium hydroxide, and sodium hydroxide. ,
Alkali metal hydroxides such as potassium hydroxide, alkaline earth metal hydroxides such as magnesium hydroxide, calcium hydroxide, barium hydroxide, sodium oxide, magnesium oxide, calcium oxide,
Alkali metal or alkaline earth metal oxides such as barium oxide, alkali metal hydrogen carbonates such as sodium hydrogen carbonate and potassium hydrogen carbonate, ammonium salts such as ammonium carbonate and ammonium hydrogen carbonate, sodium methylate, sodium ethylate, Alcoholates such as potassium methylate and potassium butyrate, alkali metals such as sodium metal, potassium metal, and sodium-potassium alloys, fatty acid salts such as sodium acetate, potassium acetate, and soaps, triethylamine, tributylamine, N,N-dimethyl Ethanolamine, laurylamine, 1,8-diazabicyclo[5.4.0]undecene-7,1,4,5,6
-tetrahydropyrimidine, formamidine, N
- Typical examples include organic bases such as ethylmorpholine. Among these, alkali metal carbonates and alkali metal hydroxides are most suitable because they have particularly excellent catalytic effects, are inexpensive, and are easy to handle.

Furthermore, when both catalysts are used together, the catalytic effect is further improved.

In the present invention, it is necessary that the amount of the base catalyst be 3 to 15% by weight based on the total amount of the neopentyl type polyol and fatty acid ester as raw materials. If the amount of the base catalyst is less than the lower limit of the above range, not only will the catalytic effect be extremely insufficient, but also the inherently poor affinity between the neopentyl polyol and the fatty acid ester will not be improved, so the two will not be compatible and alcoholysis will occur. is not proceeding smoothly. Therefore, the desired neopentyl polyol fatty acid ester is hardly produced or produced only in a very small amount. Furthermore, even if the base catalyst is used in a large amount exceeding the upper limit of the above range, the catalytic effect will not change, but rather the viscosity of the reaction mixture (reaction mass) during the reaction will increase significantly, making stirring difficult, or This is not preferable because the ratio of saponification reactions in which fatty acid salts are produced as by-products from fatty acid esters increases.

The optimum amount of this base catalyst to be used varies depending on conditions such as the type of neopentyl polyol, fatty acid ester, and base catalyst, and the reaction temperature, but it is generally 5 to 10% by weight based on the total amount of neopentyl polyol and fatty acid ester. %, the most favorable results are obtained.

In the present invention, the reaction temperature of alcoholysis is
The temperature is usually 50 to 200°C, preferably 70 to 180°C, and particularly preferably 90 to 160°C. When the temperature is below the lower limit of the above range, the reaction rate is low;
Further, even if alcoholysis is carried out at a temperature higher than the upper limit, there is no noticeable advantage, but rather it becomes disadvantageous in terms of energy consumption, and the reaction product tends to be colored, which is not preferable.

The alcoholysis reaction can be carried out satisfactorily under normal pressure, but if by-produced alcohols are removed from the reaction system by keeping it under reduced pressure or by blowing inert gas such as nitrogen gas,
The reaction can further proceed in the direction of producing the desired fatty acid ester.

Furthermore, the reaction time for alcoholysis varies depending on various conditions such as the type of neopentyl polyol, fatty acid ester, and base catalyst, their usage ratio, reaction temperature, reaction pressure, and type of reactor, but it is usually 10 minutes to 10 minutes. 20 hours, preferably 30 minutes ~
15 hours, more preferably 1 to 10 hours.

Next, various methods can be adopted to carry out the alcoholysis described above, but for example, (1) alcoholysis is carried out by charging the three components, neopentyl polyol, fatty acid ester, and base catalyst into a reactor at the same time. (2) A method in which both a fatty acid ester and a base catalyst are charged into a reactor in advance to partially saponify the fatty acid ester, and then a neopentyl polyol is charged and alcoholysis is carried out (for example, the fatty acid ester used in the reaction is If about 5 to 30% by weight of the ester is saponified in advance, alcoholysis will proceed more smoothly.) (3) After charging only the fatty acid ester into the reactor in advance, the neopentyl polyol and the base catalyst are added. Any method such as simultaneous charging and alcoholysis can be adopted.

As the reactor, a tank reactor or a tube reactor equipped with a heating device and a stirring device is usually used, but the reactor is not limited thereto. Further, a cooling device or a pressure reducing device may be attached as necessary.

As the reaction method, any of a batch method, a semi-batch method, and a continuous method can be adopted.

In the method of the present invention, fatty acid salts (i.e., soaps) are produced simultaneously with alcoholysis in which neopentyl polyol fatty acid esters are produced by the reaction of neopentyl polyols and fatty acid esters in the presence of a base catalyst. A resulting saponification reaction also occurs. and,
The saponification reaction improves the compatibility between the neopentyl polyol and the fatty acid ester, which originally have little compatibility, and this acts to promote alcoholysis (that is, the reaction for producing the neopentyl polyol fatty acid ester).

In the present invention, the progress and end point of the reaction can be roughly determined by measuring the change in viscosity, since the viscosity of the reaction mixture tends to increase as the reaction progresses. More precisely, the remaining amount of unreacted raw materials and the content of products in the reaction mixture can be determined by analyzing by gas chromatography or liquid chromatography.

The reaction product obtained by the method of the present invention contains, in addition to the target neopentyl polyol fatty acid ester, fatty acid salts, unreacted neopentyl polyol, unreacted fatty acid ester, unreacted base catalyst, and the like. These unreacted raw materials and by-products other than the neopentyl polyol fatty acid ester in the reaction product are extracted, converted to other derivatives,
It can be easily removed by appropriately combining known methods such as filtration and crystallization, and a highly pure neopentyl polyol fatty acid ester can be obtained. Further, the reaction product of the present invention can be used as it is for various purposes such as metal working oil, lubricating oil, resin additive, emulsifier, etc. without any particular purification.

According to the method of the present invention, neopentyl polyol fatty acid ester can be easily and economically advantageously produced at a much lower reaction temperature than conventional methods, even though no solvent is used. In addition, the neopentyl polyol fatty acid ester obtained by the method of the present invention has an extremely low degree of coloration and a good color tone, and the production ratio of esters with a low degree of substitution such as monoesters and diesters, which are generally of great utility value. It has the excellent feature of high

As described above, the method of the present invention easily and economically advantageously carries out the alcoholysis of fatty acid esters with neopentyl polyols, which has not necessarily been an advantageous method for producing neopentyl polyol fatty acid esters in the past. This method makes it possible to obtain products of good quality and is also suitable as a method for industrial implementation.

Next, the present invention will be explained in more detail based on examples.

Example 1 A 1-volume reactor equipped with a stirrer was charged with 150 g of pentaerythritol, 350 g of beef tallow, and 25 g of potassium carbonate, and alcoholysis was performed at 150°C. About 1 hour and 20 minutes after the start of the reaction, the reaction mixture began to foam, gradually thickened, and had a remarkable tendency to become homogeneous as a whole. After a total of 6 hours of reaction, 511 g of a fairly viscous, uniform, opaque, pale yellow liquid product was obtained. This solidified upon cooling to room temperature. After trimethylsilyl etherification treatment of the reaction product, analysis by gas chromatography revealed that pentaerythritol tallow fatty acid ester was 41.5% by weight.
(Monoester/Diester = 67/33 (weight ratio))
It was found that the remaining components were beef tallow fatty acid potassium, pentaerythritol, beef tallow fatty acid glycerides (mono-, di-, and triglycerides), glycerin, etc.

Comparative Example Alcoholysis was attempted at 150° C. in the same manner as in Example 1 except that potassium carbonate was changed to 5 g.

About 4 hours after the start of the reaction, the reaction mixture started to foam slightly, but no tendency towards thickening or homogenization was observed. Immediate phase separation into two phases was observed: and solid phase (pentaerythritol phase). Thereafter, the reaction was further continued under stirring for a total of 12 hours, but the reaction mixture was hardly observed to tend to thicken or become homogenized, so the reaction was stopped. After the reaction mixture separated into two phases, a portion of the liquid phase and a portion of the solid phase were collected and analyzed by gas chromatography. As a result, the liquid phase was mostly tallow fatty acid triglyceride, with some beef tallow. It was found that it also contains fatty acid diglyceride and tallow fatty acid monoglyceride. In addition, the solid phase part is mainly composed of pentaerythritol,
Some fatty acid potassium was also detected. However, only a small amount of the target pentaerythritol tallow fatty acid ester was detected in the solid phase.

Example 2 275 g of coconut oil and 10 g of potassium hydroxide were charged into the same reactor as in Example 1, heated at 120°C for 1 hour to partially saponify the coconut oil, and then 225 g of pentaerythritol and 20 g of potassium carbonate were charged. death,
Alcoholysis was performed by heating to 120°C. About 10 minutes after the start of the alcoholysis reaction, the reaction mixture became noticeably prone to foaming, thickening, and homogenization. After a total of 4 hours of alcoholysis reaction, the reaction mixture became a homogeneous, opaque, and white liquid, and 512 g of reaction product was finally obtained. This solidified upon cooling to room temperature. When the reaction product was analyzed in the same manner as in Example 1, it was found that pentaerythritol palm fatty acid ester was
46.5% by weight (monoester/diester = 73/27
(weight ratio)), and the remainder was found to be palm fatty acid potassium, pentaerythritol, palm fatty acid glycerides (mono-, di-, and triglycerides), glycerin, etc.

Example 3 400 g of hydrogenated beef tallow and 10 g of sodium hydroxide were placed in the same reactor as in Example 1, and heated at 110° C. for 1 hour to partially saponify the hydrogenated beef tallow. Then, 30 g of sodium carbonate was charged, followed by 100 g of pentaerythritol gradually over 1 hour.
About 30 minutes after the start of charging of pentaerythritol, the reaction mixture tended to thicken and become more homogeneous. After charging pentaerythritol,
The alcoholysis reaction was further carried out at 110° C. for 7 hours, and as a result, 517 g of a viscous, homogeneous, white, and opaque liquid reaction product was obtained. This solidified upon cooling to room temperature. When the reaction product was analyzed in the same manner as in Example 1, it contained 36.5% by weight of pentaerythritol hydrogenated tallow fatty acid ester (monoester/diester/triester = 58/37/5 (weight ratio)), The rest is hydrogenated beef tallow fatty acid sodium, pentaerythritol, hydrogenated beef tallow fatty acid glycerides (mono-, di-, and triglycerides),
It turned out to be glycerin.

Example 4 300 g of stearic acid monoglyceride (also known as glycerin monostearate), 200 g of dipentaerythritol, and 20 g of potassium carbonate were placed in the same reactor as in Example 1, and the alcoholysis reaction was carried out at 140°C for 4 hours. 508 g of a viscous, homogeneous, opaque liquid reaction product (white, solidified on cooling to room temperature) was obtained. The reaction product is shown in Example 1.
As a result of quantitative analysis using the same method as above, it was found to contain 42.1% by weight of dipentaerythritol stearate (monoester/diester = 82/18 (weight ratio)), with the remainder being potassium stearate, dipentaerythritol, and stearin. It turned out to be acid monoglyceride, glycerin, etc.

Example 5 350 g of propylene glycol dilauric acid ester, 150 g of trimethylolethane and 35 g of potassium carbonate were charged into the same reactor as in Example 1, and by-produced propylene glycol was distilled off at a temperature of 160°C and a reduced pressure of 5 mmHgabs. As a result of carrying out the alcoholysis reaction for 5 hours, 485 g of a viscous, uniform, opaque liquid reaction product (pale yellow, solidified when cooled to room temperature) was obtained. The reaction product was analyzed in the same manner as in Example 1 and found to contain 48.0% by weight of trimethylolethane laurate (monoester/diester = 69/31 (weight ratio)), with the remainder being potassium laurate. , trimethylolethane, propylene glycol laurate (mono- and diester), etc.

Claims (1)

[Claims] 1 Neopentyl-type polyol fatty acid is produced by alcoholysis by reacting a neopentyl-type polyol selected from the group consisting of pentaerythritol, dipentaerythritol, trimethylolethane, trimethylolpropane, and neopentyl glycol with a fatty acid ester. In producing the ester, the reaction is carried out without using substantially any solvent, using a base catalyst of 3 to 15% by weight based on the total amount of the raw material neopentyl polyol and fatty acid ester under heating. A method for producing neopentyl polyol fatty acid ester. 2. The method for producing a neopentyl polyol fatty acid ester according to claim 1, wherein the fatty acid ester is an ester of a fatty acid having 5 to 24 carbon atoms and a mono- to trihydric alcohol. 3. The method for producing a neopentyl polyol fatty acid ester according to claim 1, wherein the fatty acid ester is a fatty acid glyceride. 4. The method for producing a neopentyl polyol fatty acid ester according to claim 1, wherein the base catalyst is an alkali metal base catalyst. 5. The method for producing a neopentyl polyol fatty acid ester according to claim 1, wherein the base catalyst is at least one selected from alkali metal carbonates and alkali metal hydroxides. 6. The method for producing a neopentyl polyol fatty acid ester according to claim 1, wherein alcoholysis is carried out at 50 to 200°C.