JP2013170148A - Sucrose aromatic monocarboxylate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sucrose aromatic monocarboxylate which is excellent in compatibility with amorphous resins and crystalline resins, and improves their moldability, physical properties, flexibility and impact resistance, and the like, can control thermal coloration, and is excellent in thermal stability.SOLUTION: A sucrose aromatic monocarboxylate is an ester of sucrose with an aromatic monocarboxylic acid represented by general formula (I) (wherein, R-Rare each independently a group selected from H, alkyl or alkoxy), having the content of substituted products of ≤penta-substituted products in an amount of ≤2.0 wt.%, and a halogen content of ≤100 ppm.

Description

  The present invention is an excellent sucrose aromatic as a resin modifier that is excellent in phase solubility with an amorphous resin or a crystalline resin and improves molding processability, physical properties, flexibility, impact resistance, etc. The present invention relates to a sucrose aromatic monocarboxylic acid ester which is a monocarboxylic acid ester and has excellent thermal stability and can suppress coloring due to heating.

  As resin modifiers, sucrose derivatives such as sucrose benzoate are known, and molding processability and physical properties of amorphous resins such as ABS resin, polyvinyl chloride resin, epoxy resin and unsaturated polyester resin are known. Or improving the flexibility and impact resistance of crystalline polyester (Patent Documents 1 to 3).

  However, since sucrose benzoate is a sucrose derivative, when it is added as a modifier, there is a problem in the hue of products made of these resins and the thermal stability of the hue. That is, sucrose benzoate is generally produced using an organic solvent, but first, coloring occurs in the heating process for removing the organic solvent in the production process. More specifically, since the melting point of sucrose benzoate is 80 to 90 ° C., the removal of the organic solvent used in the production process usually requires heating at 100 ° C. or higher, preferably 110 ° C. or higher. However, under such heating conditions of 100 ° C. or higher, coloring of sucrose benzoate proceeds. The degree of coloring tends to become more prominent as the proportion of components having a low esterification degree in sucrose benzoate increases or the average degree of ester substitution decreases. In addition, if we try to shorten the processing time using special processing equipment (for example, a thin film distillation apparatus) and suppress the thermal history of sucrose benzoate when removing the organic solvent, the coloring is suppressed as much as possible. However, after adding sucrose benzoate to the resin, there is a problem that coloring occurs due to a heat history when the resin is processed and molded.

  For this reason, sucrose benzoate has never been satisfactory as a resin modifier requiring optical transparency.

JP-A-52-81362 Japanese Patent Publication No.62-15582 JP-A-6-255274

  The present invention is an excellent sucrose aromatic as a resin modifier that is excellent in phase solubility with an amorphous resin or a crystalline resin and improves molding processability, physical properties, flexibility, impact resistance, etc. An object of the present invention is to provide a sucrose aromatic monocarboxylic acid ester which is a monocarboxylic acid ester and can suppress coloring due to heating and has excellent thermal stability.

  As a result of diligent research aimed at solving the above-mentioned problems, the present inventors suppressed coloring when receiving a thermal history by suppressing the halogen content in the sucrose aromatic monocarboxylic acid ester to a low level. The present invention was completed by finding out what can be done and further studying it.

（式中、Ｒ¹〜Ｒ⁵は、独立に、水素原子、アルキル基およびアルコキシ基から選択される基である。）
で示される芳香族モノカルボン酸とのエステルであって、５置換体以下の置換体の含有量が２．０重量％以下、かつ、ハロゲンの含有量が１００ｐｐｍ以下であるショ糖芳香族モノカルボン酸エステルに関する。 That is, the present invention
Sucrose and general formula (I)

(In the formula, R ^{1 to} R ⁵ are groups independently selected from a hydrogen atom, an alkyl group, and an alkoxy group.)
The sucrose aromatic monocarboxylic acid is an ester with an aromatic monocarboxylic acid represented by the formula: It relates to acid esters.

  The sucrose aromatic monocarboxylic acid ester preferably has an average degree of substitution of 7.0 or more.

  The sucrose aromatic monocarboxylic acid ester preferably has a hue in a 50% toluene solution of APHA 10 or less.

  The sucrose aromatic monocarboxylic acid ester preferably has a hue of APHA 30 or less in a 50% toluene solution after heating at 160 ° C. for 3 hours.

  The present invention also relates to a resin modifier comprising the sucrose aromatic monocarboxylic acid ester.

  Furthermore, the present invention relates to a method for producing a sucrose aromatic monocarboxylic acid ester having a hue in a 50% toluene solution of APHA of 10 or less, comprising a step of setting the halogen content to 100 ppm or less. The present invention relates to a method for producing a monocarboxylic acid ester.

  The sucrose aromatic monocarboxylic acid ester of the present invention has excellent compatibility with amorphous resins and crystalline resins, and can improve molding processability, physical properties, flexibility, impact resistance, and the like. On the other hand, it also has an excellent feature that coloring due to heating can be suppressed. Therefore, it can be used as a modifier for resins that require optical transparency.

  In addition, the sucrose aromatic monocarboxylic acid ester of the present invention has a high esterification ratio of the alcohol portion of sucrose, that is, a relatively low ratio of low-substituted products, and therefore has more excellent thermal stability. Show.

  Furthermore, according to the production method of the present invention, a sucrose aromatic monocarboxylic acid ester exhibiting such excellent characteristics can be easily produced without using a special treatment facility (for example, a thin film distillation apparatus). Therefore, it is industrially advantageous in terms of manufacturing cost.

<Object>
In the aromatic monocarboxylic acid (I) of the sucrose aromatic monocarboxylic acid ester of the present invention, R ^{1 to} R ⁵ are preferably each independently a hydrogen atom or an alkyl group, and all are hydrogen atoms. More preferably, benzoic acid or one of them (preferably R ³ ) is an alkyl group and the remainder is a hydrogen atom.

  As an alkyl group, a C1-C20 thing is mentioned, Among these, a C1-C5 thing is preferable, More preferably, they are a methyl group, an ethyl group, a propyl group, or an isopropyl group. Examples of the alkoxy group include those having 1 to 20 carbon atoms, and among these, those having 1 to 5 carbon atoms are preferable, and a methoxy group, an ethoxy group, a propyloxy group, or an isopropyloxy group is more preferable.

  The sucrose aromatic monocarboxylic acid ester of the present invention preferably has a high ratio of esterification of the alcohol part of sucrose. Specifically, the content of a substituted product having 5 or less substituents is 2.0% by weight. Hereinafter, it is preferably 1.0% by weight or less, more preferably 0.5% by weight or less, and still more preferably 0.3% by weight or less. Here, the 5-substituted product refers to a product in which 5 hydroxyl groups out of a total of 8 hydroxyl groups of sucrose are esterified with an aromatic monocarboxylic acid. In the present specification, for the sake of convenience, a substitution product having 5 or less substitutions is referred to as a low substitution product, and the other substitution product is referred to as a high substitution product.

  In addition, another preferred example of the sucrose aromatic monocarboxylic acid ester of the present invention is one having a content of 6 substituents or less and less than 5% by weight.

  The sucrose aromatic monocarboxylic acid ester of the present invention preferably has a large average value of the esterification rate of the alcohol portion of sucrose (hereinafter referred to as “average ester substitution degree” or “average substitution degree”). Specifically, the average ester substitution degree is, for example, 7.0 or more, and preferably 7.3 or more.

  In the sucrose aromatic monocarboxylic acid ester of the present invention, the halogen content is 100 ppm or less. Examples of the halogen include fluorine, chlorine, bromine, iodine, etc. Among them, the chlorine content has a great influence.

  The preferred halogen content is 90 ppm or less, more preferably 60 ppm or less, still more preferably 30 ppm or less, and even more preferably 20 ppm or less. The preferable chlorine content is 80 ppm or less, more preferably 55 ppm or less, still more preferably 25 ppm or less, and still more preferably 17 ppm or less.

  In the sucrose aromatic monocarboxylic acid ester of the present invention, the hue in a 50% toluene solution is preferably 10 or less. In the sucrose aromatic monocarboxylic acid ester of the present invention, the hue in a 50% toluene solution after heating at 160 ° C. for 3 hours is preferably 30 or less, more preferably 25 or less, and still more preferably 15 It is as follows. When the hue exceeds 30, when used as a resin modifier, the appearance (hue) and optical transparency of the resin tend to be lowered.

<Production method>
(Halogen removal process)
The sucrose aromatic monocarboxylic acid ester according to the present invention can be produced by a production method comprising a step of setting the halogen content to 100 ppm or less.

  As the step of setting the halogen content to 100 ppm or less, any method that is usually used in this field can be used as long as the object can be achieved. Specific examples of such a method include, for example, sucrose. And subjecting an ester obtained by subjecting to a monocarboxylic acid and an aromatic monocarboxylic acid to an esterification reaction. The washing with water can be carried out by a conventional method, for example, adding water to the mixture after completion of the esterification reaction, stirring the mixture in a hot water bath, and allowing to stand to separate and remove the aqueous phase. Can be implemented. The hot water bath temperature is preferably 40 to 60 ° C. If it is 40 ° C. or lower, there is a tendency to be insufficiently washed. The stirring is not particularly limited as long as it is a time sufficient for the halide ions and other halogen-containing compounds to move to the aqueous phase, and it is usually sufficient to perform the stirring for about 30 minutes. The number of washings varies depending on the raw materials used, ester reaction conditions, etc., but when using high-purity raw materials with few impurities (for example, high-purity benzoyl chloride (> 99.5%), etc.), It is enough to go about 8 times.

  In the present invention, it is effective to use a raw material having a low halogen content in advance in order to set the halogen content in the sucrose aromatic monocarboxylic acid ester to 100 ppm or less. Therefore, it is preferable to use a high-purity halogenated aromatic monocarboxylic acid as the esterifying agent. Examples of such a high-purity halogenated aromatic monocarboxylic acid include high-purity benzoyl chloride (> 99.5%) (manufactured by Kawaguchi Chemical Co., Ltd.).

  As described above, after passing through the step of setting the halogen content in the sucrose aromatic monocarboxylic acid ester to 100 ppm or less, the solvent used in the esterification reaction is distilled off by a conventional method, whereby the target product of the present invention is obtained. Can be obtained. In this case, since the halogen content is 100 ppm or less in advance, in the present invention, the solvent can be distilled off by a conventional method without using a special treatment facility (for example, a thin film distillation apparatus). Thus, the desired product with suppressed coloring can be obtained.

(Ester synthesis)
In the present invention, the esterification reaction between sucrose and an aromatic monocarboxylic acid can be carried out by a conventional method, for example, according to the method for producing sucrose benzoate described in JP-A-61-4839. be able to.

  That is, it can be produced by subjecting sucrose, which is a raw material, and a chloride of an aromatic monocarboxylic acid to an esterification reaction in a mixed solution of a hydrophilic solvent and water in the presence of an alkaline compound. Suitable hydrophilic solvents include, for example, ketone solvents such as acetone, methyl ethyl ketone, and cyclohexanone, ether solvents such as dioxane and tetrahydrofuran, ester solvents such as methyl acetate, and alcohol solvents such as tertiary butanol. Can be used.

  Examples of the alkaline compound include sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, sodium hydrogen carbonate, potassium hydrogen carbonate, ammonia, trimethylamine, and triethylamine.

  The mixing ratio of the hydrophilic solvent and water is preferably such that the water content of the uniform liquid layer composed of both is 7 to 80%. This is because these hydrophilic solvents dissolve the aromatic monocarboxylic acid chloride or product ester, which is one of the raw materials, while the other raw material sucrose alone does not dissolve or reacts at all. From the point of view of efficiency, it only dissolves to the extent that it is not practically used. However, by mixing water, which is a good solvent for sucrose, it becomes possible to dissolve sucrose to the extent that the mixed solution is practically used. It is. Therefore, by utilizing such properties of the hydrophilic solvent, the reaction rate of sucrose and the aromatic monocarboxylic acid chloride can be regulated, and as a result, the sucrose / aromatic monocarboxylic acid chloride Depending on the charged amount (molar ratio), it is possible to produce esters having different ratios of low substitution products and different degrees of average ester substitution. For example, by increasing the amount of aromatic monocarboxylic acid chloride charged relative to the amount of sucrose, an ester having a relatively low proportion of low-substituted products or a relatively large average degree of ester substitution is obtained. On the contrary, by reducing the amount of aromatic monocarboxylic acid chloride charged relative to the amount of sucrose, a relatively high proportion of low-substituted products or a relatively high degree of average ester substitution A small ester body can be obtained.

  As a method for the reaction, sucrose and an aromatic monocarboxylic acid chloride are dissolved or suspended in a mixture of a hydrophilic solvent and water, and an equivalent amount or a slight excess of an alkaline compound is mixed with the aromatic monocarboxylic acid chloride. Add or drop sucrose and alkaline compound in the mixed solution, drop the aromatic monocarboxylic acid chloride, or dissolve or suspend sucrose in the mixed liquid and add the aromatic monocarboxylic acid chloride And the alkaline compound can be dropped simultaneously or alternately.

  Although reaction temperature can be employ | adopted to -15 degreeC-100 degreeC, More preferably, it is -10 degreeC-30 degreeC. However, after all the reaction raw materials have been dropped, the reaction may be completed in a high temperature range in order to promote the completion of the reaction.

  It is desirable to keep the pH during the reaction weakly alkaline. On the other hand, under strong alkalinity (for example, pH 13 or higher depending on the reaction temperature, etc.), the side reaction of hydrolysis of the aromatic monocarboxylic acid is remarkable.

  The reaction time is not particularly limited as long as the reaction between the raw materials can sufficiently complete the reaction. Although the specific time depends on the amount of the raw material compound and various conditions, it is usually sufficient to perform for about 1 hour.

<Application>
The sucrose aromatic monocarboxylic acid ester of the present invention is useful as a resin modifier, and in particular, has an excellent feature of being able to suppress coloring due to heating, so that it is a resin that requires optical transparency. It can be used as a modifier.

  Examples of the resin to which the sucrose aromatic monocarboxylic acid ester of the present invention is added include amorphous resins such as ABS resin, polyvinyl chloride resin, epoxy resin and unsaturated polyester, and crystalline resins such as crystalline polyester resin. Can be mentioned. Resin can be suitably selected according to the use. In addition, the sucrose aromatic monocarboxylic acid ester of the present invention to be added to the resin can be appropriately selected in accordance with the type and application of the resin, in terms of the ratio of the low substitution product and the degree of ester substitution.

  The ABS resin is not particularly limited. For example, polybutadiene, styrene-butadiene copolymer, acrylonitrile-butadiene copolymer, chlorinated polyethylene, acrylic rubber (for example, methyl acrylate, ethyl acrylate, Butyl acrylate, etc.) and acrylonitrile, styrene, acrylic acid, acrylic acid amide, 2-chloroethyl vinyl ether, and other rubbery polymers such as acrylonitrile, styrene, α-methylstyrene, methacrylic acid Examples thereof include those obtained by graft polymerization of methyl and the like, and further include acrylonitrile-polybutadiene-styrene graft copolymers. ABS resin may be used individually by 1 type, and may use 2 or more types together.

  The polyvinyl chloride resin is not particularly limited, and for example, vinyl chloride homopolymer resin, chlorinated vinyl chloride resin, one or more monomers copolymerizable with vinyl chloride monomer, A vinyl chloride copolymer resin (for example, vinyl acetate-vinyl chloride copolymer, ethylene-vinyl chloride copolymer, etc.) obtained by random copolymerization or block copolymerization, or a functional group such as a hydroxyl group is grafted to the above resin. And a resin obtained by reacting such a functional group with a reactive compound and graft-bonding them. A polyvinyl chloride resin may be used individually by 1 type, and may use 2 or more types together.

  The epoxy resin is not particularly limited. For example, bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, phenol novolac type epoxy resin, alkylphenol novolac type epoxy resin, phenol biphenyl aralkyl epoxy resin. Aralkyl type epoxy resins, biphenol type epoxy resins, naphthalene type epoxy resins, dicyclopentadiene type epoxy resins, biphenyl type epoxy resins, anthracene type epoxy resins, condensates of phenols and aromatic aldehydes having phenolic hydroxyl groups Examples include epoxidized products, triglycidyl isocyanurate, and alicyclic epoxy resins. An epoxy resin may be used individually by 1 type, and may use 2 or more types together.

  The unsaturated polyester resin is not particularly limited. For example, the unsaturated polyester resin is synthesized by addition reaction or dehydration condensation reaction of α, β-olefinic unsaturated dicarboxylic acid or its anhydride and glycol. Further, saturated dicarboxylic acids, aromatic dicarboxylic acids or anhydrides thereof, or dicyclopentadiene that reacts with carboxylic acids can be used in combination. Examples of the α, β-olefin unsaturated dicarboxylic acid include maleic acid, fumaric acid, itaconic acid, citraconic acid and anhydrides of these dicarboxylic acids. Examples of dicarboxylic acids used in combination with these α, β-olefinic unsaturated dicarboxylic acids include, for example, adipic acid, sebacic acid, succinic acid, phthalic anhydride, orthophthalic acid, isophthalic acid, terephthalic acid, tetrahydrophthalic acid And tetrachlorophthalic acid. Among these, it is preferable to use fumaric acid as the α, β-olefinic unsaturated dicarboxylic acid and isophthalic acid as the dicarboxylic acid. An unsaturated polyester resin may be used individually by 1 type, and may use 2 or more types together.

  The crystalline polyester resin is not particularly limited. For example, polyethylene terephthalate, poly-1,4-butylene terephthalate, polyethylene-2,6-naphthalate, polycyclohexanedimethanol terephthalate, poly-1,4-butylene. Examples thereof include crystalline polyesters such as diphenyl-4,4′-dicarboxylate, polyethyleneoxybenzoate, poly-1,3-propylene terephthalate, poly-1,6-hexylene terephthalate, and among these, polyethylene terephthalate, poly- 1,4-butylene terephthalate and polyethylene-2,6-nanophthalate are preferred. A crystalline polyester resin may be used individually by 1 type, and may use 2 or more types together.

  In addition, various additives, such as an impact strength modifier, a stabilizer, a lubricant, a filler, a pigment, a foaming agent, and an ultraviolet stabilizer, can be added to these resins as necessary.

  The mixing ratio of the sucrose aromatic monocarboxylic acid ester of the present invention to the resin is preferably 1 to 40 parts, more preferably 1 to 30 parts, relative to 100 parts of the resin. If the amount is less than 1 part, the intended performance tends not to be obtained, and if it exceeds 40 parts, the possibility of bleeding out due to long-term storage or the like increases.

In the present specification, the term “parts” simply means “parts by weight”.
The “average degree of substitution” in the sucrose aromatic monocarboxylic acid ester is a value determined by proton nuclear magnetic resonance ( ¹ H-NMR). Further, the ratio of each substitution product when calculating the ratio of “low substitution product” is a value obtained by liquid chromatography mass spectrometry (LC-MS). The halogen content (ppm) is a value measured by inductively coupled plasma optical emission spectrometry (ICP).

  The present invention will be described in detail based on examples, but the present invention is not limited to these examples.

<Used raw materials>
Sucrose: ≧ 99.9%, Benzoyl chloride manufactured by Shinko Sugar Co., Ltd. (1): High-purity product (> 99.5%), Benzoyl chloride manufactured by Kawaguchi Pharmaceutical Co., Ltd. (2): Normal product> 99.0 (Made by Jiangsu Qiangsheng Chemical Co., Ltd.)

1. Synthesis Example 1
<Sucrose benzoate (proportion of 5-substituted product or less: 0.2%)>
3L of sucrose and 70 parts of water were charged and dissolved in a 1 L five-necked flask equipped with a stirring rod, thermometer, cooling condenser, dropping funnel, pH electrode connected to a pH meter, and then 10 ° C or less in a water bath. While cooling, 100 parts of cyclohexanone containing 106.7 parts of benzoyl chloride (1) was gradually added. Thereafter, while maintaining the temperature at 20 ° C. or lower, 69.0 parts of a 48% sodium hydroxide aqueous solution was added from the dropping funnel at such a rate that the pH was maintained at 10-11. After removing the water bath and stirring for 1 hour at room temperature of 20-30 ° C. to complete the reaction, a small amount of sodium carbonate was added and heated to convert the remaining trace of benzoyl chloride into sodium benzoate. . Thereafter, the aqueous phase was separated and removed by allowing to stand for about 30 minutes.
70 parts of water was newly added, the temperature was raised to 40 to 50 ° C. in a hot water bath, stirred for 30 minutes, and allowed to stand for about 30 minutes to separate and remove the aqueous phase. After the same operation was further repeated 7 times (total number of washings: 8 times), the temperature was raised to 120 ° C., and the solvent was distilled off under reduced pressure to obtain the title sucrose benzoate.
The average degree of substitution, the ratio of each substituent, the ratio of five or less substituents, and the halogen content were measured (the same applies to the objects of the following examples and comparative examples).

Example 2
<Sucrose benzoate (proportion of 5-substituted product or less: 0.0%)>
The title sucrose benzoate was obtained in the same manner as in Example 1 except that 113.8 parts of benzoyl chloride (1) and 73.6 parts of 48% sodium hydroxide aqueous solution were used and the number of washings was 5 times.

Comparative Example 1
<Sucrose benzoate (proportion of 5-substituted product or less: 0.2%)>
The title sucrose benzoate was obtained in the same manner as in Example 1 except that the number of washings was one.

Comparative Example 2
<Sucrose benzoate (proportion of 5-substituted product or less: 0.1%)>
The title sucrose benzoate was obtained in the same manner as in Example 1 except that benzoyl chloride (2) was used in place of benzoyl chloride (1) and the number of washing was changed to 8.

Comparative Example 3
<Sucrose benzoate (proportion of 5-substituted product or less: 0.1%)>
The title sucrose benzoate was obtained in the same manner as in Comparative Example 2 except that the number of washings was three.

Comparative Example 4
<Sucrose benzoate (proportion of 5-substituted product or less: 0.0%)>
The title sucrose benzoate was obtained in the same manner as in Example 2 except that the number of washings was one.

2. Evaluation <Hue>
The hue of each ester 25 g obtained in the above Examples and Comparative Examples was determined according to the method described in JIS K2421. That is, each sample was diluted to 50% with toluene, and the numerical value of the APHA standard solution (Hazen color number: APHA) that was judged to be the same when the hue of the diluted solution was compared with the naked eye was recorded.
<Hue stability>
5 g of each ester obtained in the above Examples and Comparative Examples was put into a test tube and heated in an oil bath at 160 ° C. for 3 hours. About each sample obtained in this way, the hue was determined by the same method as described in the section of <Hue> above.

  The results are shown in Table 1.

  As shown in Table 1, in Examples 1 and 2 of the present invention, not only the product hue was excellent as APHA 10 or less, but also changed to hue (APHA) after heating at 160 ° C. for 3 hours. Was not seen, indicating high thermal stability. On the other hand, in Comparative Examples 1 to 4, a large change in hue was observed before and after heating, and the degree of change was observed to increase as the halogen content increased.

  The sucrose aromatic monocarboxylic acid ester of the present invention has excellent compatibility with amorphous resins and crystalline resins, and can improve molding processability, physical properties, flexibility, impact resistance, and the like. On the other hand, since it has the outstanding feature that coloring by heating can be suppressed, it is useful as a modifier for resins, particularly resins that require optical transparency.

Claims (6)

Sucrose and general formula (I)

(In the formula, R ^{1 to} R ⁵ are groups independently selected from a hydrogen atom, an alkyl group, and an alkoxy group.)
The sucrose aromatic monocarboxylic acid is an ester with an aromatic monocarboxylic acid represented by the formula: Acid ester. The sucrose aromatic monocarboxylic acid ester according to claim 1, having an average degree of substitution of 7.0 or more. The sucrose aromatic monocarboxylic acid ester according to claim 1 or 2, wherein the hue in a 50% toluene solution is APHA 10 or less. The sucrose aromatic monocarboxylic acid ester according to any one of claims 1 to 3, wherein the hue in a 50% toluene solution after heating at 160 ° C for 3 hours is APHA 30 or less. The resin modifier which comprises the sucrose aromatic monocarboxylic acid ester of any one of Claims 1-4. A method for producing a sucrose aromatic monocarboxylic acid ester having a hue in a 50% toluene solution of APHA of 10 or less, which comprises a step of setting the halogen content to 100 ppm or less. Production method of acid ester.