JP2003139666A - Method for extracting and analyzing soluble oligomer in heat resistant resin - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for extracting and analyzing soluble oligomer contained in resin having softening point of 200 deg.C or above conveniently. SOLUTION: In the method for extracting soluble oligomer contained in resin having softening point of 200 deg.C or above, oligomer is extracted from the resin using a solvent containing carbon, hydrogen and another element under such temperature conditions as not lower than 15 deg.C but lower than the critical temperature of the solvent and the softening point of the resin and under pressurization conditions. The method for analyzing soluble oligomer contained in resin having softening point of 200 deg.C or above includes an operation for extracting soluble oligomer by that extracting method.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a method for extracting and analyzing a soluble oligomer in a heat resistant resin.

[0002]

2. Description of the Related Art A resin having a softening point of 200.degree. C. or higher and heat resistance (hereinafter sometimes referred to as "heat resistant resin").
Are widely used as materials for electronic parts such as connectors and structural materials used under high temperature conditions. It is known that the heat-resistant resin may contain a soluble oligomer, and the soluble oligomer may cause a decrease in strength and durability at high temperature of the heat-resistant resin. Therefore, it is very important to extract soluble oligomers and measure and analyze the amount thereof in order to improve the physical properties of the heat-resistant resin and to control quality.

However, unlike resins having low heat resistance, it has been difficult to extract soluble oligomers from heat resistant resins. It was difficult to extract soluble oligomers from wholly aromatic polyesters, which are particularly difficult to penetrate into solvents among heat-resistant resins. The Soxhlet extraction method is known as the extraction method. However, the Soxhlet extraction method has a problem that when the resin is a heat-resistant resin, no matter how the temperature conditions are adjusted, the oligomer cannot be extracted or the extraction takes a lot of time in many cases. Therefore, a simple method for extracting a soluble oligomer from a heat-resistant resin, especially from a wholly aromatic polyester resin has been demanded.

On the other hand, as an extraction method other than the Soxhlet extraction method, in Japanese Patent Publication No. 8-510065, a mixture of methylene chloride, ethanol, toluene, and acetone is used as a solvent, which is lower than a supercritical condition of 50 to 50. 1
Under the temperature condition of 50 ° C., 500 to 2500 psi (3.5
The apparatus and method for extracting an additive from a polymer to obtain a sample for analysis under a pressure condition of ~ 18 MPa) are described. When the apparatus and method are applied to a heat resistant resin, an oligomer It was not described that it could be extracted.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to provide a method for easily extracting a soluble oligomer contained in a resin having a softening temperature of 200 ° C. or higher and further analyzing it.

[0006]

Means for Solving the Problems The inventors of the present invention have conducted extensive studies on a method for extracting and analyzing a soluble oligomer in a heat resistant resin, and using a solvent containing an element other than carbon and hydrogen as a solvent. It was found that it is possible to extract a soluble oligomer from a heat-resistant resin when the extraction operation is performed under pressure conditions and at a temperature lower than both the critical temperature and the softening temperature of the resin at a temperature of 15 ° C. or higher. Has been completed.

That is, the present invention is a method of extracting a soluble oligomer contained in a resin having a softening temperature of 200 ° C. or higher, using a solvent containing carbon, hydrogen and an element other than those, and having a softening temperature of 15 ° C. or higher. Provided is a method for extracting an oligomer from a resin under a temperature condition that is lower than a critical temperature and lower than a softening temperature of the resin and under a pressure condition. The present invention also provides a method for analyzing a soluble oligomer contained in a resin having a softening temperature of 200 ° C. or higher, which comprises the step of extracting the soluble oligomer by the above-mentioned extraction method, and analyzing the soluble oligomer in the resin. .

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in detail below. The solvent used in the present invention contains carbon, hydrogen and other elements. For the extraction of soluble oligomers contained in a resin having a softening temperature of 200 ° C. or higher, a solvent consisting of only carbon and hydrogen has been used in the past, but surprisingly, in addition to carbon and hydrogen, other elements such as The present inventors have found that a soluble oligomer can be extracted by using a solvent containing oxygen, nitrogen and the like. As the solvent used in the present invention, acetone, methanol, ethanol, 2
-It is preferably at least one selected from the group consisting of propanol, tetrahydrofuran, dioxane, methylene chloride, chloroform, acetonitrile, N-methylpyrrolidone, dimethylformamide, pyridine and ethyl acetate. Further, in order to perform the analysis after extraction easily and with high accuracy, it is preferable that the purity is as high as 99% or more.

The resin from which soluble oligomers are extracted in the present invention is a resin having a softening temperature of 200 ° C. or higher. In the present invention, the softening temperature of a resin means a melting point for a resin having a melting point and a deflection temperature under load for a resin having an unclear melting point. Even if the resin has a softening temperature of 200 ° C or higher, especially a wholly aromatic polyester resin,
Aromatic polyether resin, polyether sulfone resin,
The method of the present invention is preferably applicable to a polyether ether ketone resin, a polyphenylene sulfide resin, a polyimide resin, an aramid resin, a fluororesin resin or a mixture of two or more kinds of the above resins, and particularly preferably to a wholly aromatic polyester resin. it can.

In the present invention, the soluble oligomer has a repeating structural unit of a polymer constituting the heat resistant resin to be extracted in the molecule, and the degree of polymerization of the repeating structural unit is 5 or less, or the molecular weight is It is an organic compound that is 1000 or less, and is an organic compound that is soluble in the solvent used for extraction. The soluble oligomer in the present invention also includes a monomer. In the method of the present invention, not all oligomers and monomers can be extracted, and the extractable oligomers and monomers change depending on the solvent. Therefore, the oligomers and monomers that can be extracted in the present invention are soluble in the solvent selected. The oligomers and monomers that are soluble in the selected solvent are called soluble oligomers. Further, in the present invention, a polymer and / or a monomer contained in the heat resistant resin and having a polymerization degree of the repeating structural unit of the polymer constituting the heat resistant resin of 5 or less is used in the process of molding or using the heat resistant resin. The soluble oligomer also includes an organic compound that is a derivative formed by changing the structure and is soluble in the solvent used for extraction.

In the present invention, the heat-resistant resin can be analyzed regardless of its shape as long as it is in a solid state. For example, the method of the present invention can be applied to any of fibrous, film-like, molded, elastomeric, coating-like, powder-like, pellet-like, and powdered by crushing the heat-resistant resin. It is preferable to do so because the analysis result can be obtained with good reproducibility in a short time.

The heat resistant resin in the present invention may contain an inorganic composition. For example, glass fiber, silica alumina fiber, alumina fiber, fibrous reinforcing material such as carbon fiber, needle-like reinforcing material such as aluminum borate whiskers, potassium titanate whiskers; glass beads, silica, talc, mica, graphite, w Inorganic fillers for reinforcement and modification purposes such as rustite, dolomite, aluminum powder, iron powder, aluminum hydroxide, and inorganic phosphorus compounds are usually included in the heat-resistant resin during the extraction operation, so they are included. May be. Depending on the solvent used, it dissolves in the solvent, but since it does not affect the analysis result because it can be separated during analysis, it may be included.

Further, the heat-resistant resin may contain a monomer, an oligomer, or an organic substance other than the polymer, which is composed of a repeating structural unit of a polymer constituting the heat-resistant resin. Even if it has been extracted by the method of the present invention, the total weight of the extracted organic substances and soluble oligomers can be measured, and the variation in the value depending on the production lot can be used for quality control. Further, since the organic matter is separated from the soluble oligomer during the analysis operation, the soluble oligomer can be analyzed. The above-mentioned organic substances contained in the heat-resistant resin include flame retardants such as halogen compounds and organic phosphorus compounds; plasticizers such as aromatic esters and chlorinated paraffins;
Release agents such as waxes, oils and metal soaps; coloring agents such as dyes and pigments; antioxidants such as phenol compounds, amine compounds, phosphorus compounds, benzophenone compounds, carbodiimide compounds; heat stabilizers; One or more usual additives such as an ultraviolet absorber, an antistatic agent and a surface modifier may be contained.

Further, when the heat resistant resin of the present invention is blended with a small amount of resin having a softening temperature of less than 200 ° C., or the heat resistant resin to be analyzed in the present invention is present as a component of the polymer alloy. In some cases, soluble oligomers of the heat resistant resin in the blend can be extracted and analyzed by the method of the present invention.

In the method of the present invention, pressure is applied together with the solvent in the liquid phase under a temperature condition in which the heat resistant resin is not softened. When the heat-resistant resin is softened, the heat-resistant resin starts to decompose, the decomposed product may be mixed in the soluble oligomer contained in the heat-resistant resin, and the resin may deform and block the piping of the device. Absent. Also, when the temperature of the solvent is higher than the critical temperature, the reactivity with the resin increases,
It is not preferable because it may react with a part or all of the resin to decompose the heat resistant resin. On the other hand, if the temperature is 15 ° C or lower, the extraction time becomes long, which is not convenient and is not preferable. The temperature condition for the extraction is appropriately determined according to the critical temperature of the solvent and the softening temperature of the heat-resistant resin, but the reaction temperature is not lower than the boiling point of the solvent used in the extraction at atmospheric pressure and is 10 ° C or more lower than the critical temperature of the solvent. The conditions are preferably set, and the range of 90 ° C or higher and 200 ° C or lower is more preferable.

Regarding the pressure condition of the reaction, it is necessary to carry out under pressure in order to enhance the permeability of the solvent into the heat resistant resin, and it is preferably 3 MPa or more. If the pressure is too high, the cost of the container increases, so 20 MPa or less is preferable. More preferably 5 MPa or more and 15 MPa or less.

In the present invention, the method of extracting the soluble oligomer is not particularly limited, and may be a batch reaction or a flow reaction. The extraction may be carried out with stirring or without stirring. As the heat source, a substance whose temperature can be controlled within the range used for extraction is preferable, and an oven used for gas chromatography or the like, a fluidized bed sand bath, a salt (molten salt) bath, the above-mentioned Tokukaihei No. 8-5100.
The device described in Japanese Patent Publication No. 65 is exemplified.

The extraction time depends on the type of heat resistant resin, the temperature,
The time for extracting a sufficient soluble oligomer from the heat-resistant resin may be appropriately determined according to the conditions such as the pressure and the type of solvent, but is preferably in the range of 5 minutes to 120 minutes, and preferably 10 minutes to 3 minutes.
The range of 0 minutes is more preferable. Moreover, in order to increase the yield of the soluble oligomer, it is also preferable to repeat the above-mentioned extraction twice or more.

The weight ratio of the solvent to the heat-resistant resin is appropriately determined depending on the combination of the heat-resistant resin and the solvent used and the volume of the container used for extraction. Generally, the solvent is 1 time the heat-resistant resin. The range is preferably 100 times or more and 100 times or less, more preferably 5 times or more and 50 times or less.

In the method of the present invention, after the extraction is completed, the soluble oligomer obtained by the extraction can be analyzed. In addition, in the present invention, the analysis of a soluble oligomer means performing a structural analysis of each component of the oligomer and / or quantifying the component of the soluble oligomer.

In order to analyze the extracted soluble oligomer, first, the soluble oligomer is separated. The method for separating the soluble oligomer is not particularly limited, but a chromatography method is usually used. Examples of the chromatography method include a liquid chromatography method, a size exclusion chromatography method, a supercritical fluid chromatography method, a gas chromatography method and a thin layer chromatography method, which are easy to analyze and have good separation. , Liquid chromatography, size exclusion chromatography and gas chromatography are preferred.

The detectors of the above-mentioned chromatography method include an ultraviolet absorption detector, a hydrogen flame ionization (FID) detector, a mass spectrometry detector, a fluorescence detector, an NMR detector, an infrared spectroscopy (IR) detector, A parallax refraction (RI) detector, a solvent evaporation type light scattering detector, and the like are used, but not limited thereto. Ultraviolet absorption detectors, mass spectrometry detectors, NMR detectors, RI detectors, and solvent evaporation type light scattering detectors are used as detectors for liquid chromatography method and size exclusion chromatography method, and detection for supercritical fluid chromatography method. FID detector, mass spectrometric detector,
Ultraviolet absorption detector, NMR detector, and solvent evaporation type light scattering detector are FI as detectors for gas chromatography method.
A D detector and a mass spectrometric detector are preferably used. It is preferable that the detector is directly connected to the chromatography device for easy analysis, but the analysis can also be performed by the method of elution with the mobile phase from the chromatography device as it is, or by concentrating it and detecting it by the detector. be able to.

In the extraction operation of the present invention, depending on the combination of the heat-resistant resin and the solvent, precipitation of an insoluble component in the solvent may be observed when the solvent is returned to normal pressure. In such a case, Although the insoluble matter is not limited to a particular method, it is preferable to remove the insoluble matter before it is injected into the chromatography device by filtration or centrifugation. In addition, when the amount of soluble oligomer to be extracted is small or the amount of solvent is large by repeating the extraction operation twice or more, the method is not limited as necessary, but removal of the solvent under reduced pressure, ultrafiltration, etc. It is also possible to reduce the amount of solvent using the method.

For the structural analysis of the soluble oligomer separated by the above method, when the chromatography is used as described above, a usual analysis method can be used. That is, although not particularly limited, there are, for example, a method of comparing retention time with a compound having a known structure, a structure analysis method by mass spectrum, a structure analysis method by NMR spectrum, a structure analysis method by IR spectrum and the like. In addition, the method of quantitative analysis is not particularly limited, for example, an absolute calibration curve method determined from the ratio of the detection peak area of the soluble oligomer to a standard sample, and a standard substance different from the soluble oligomer is added to measure both. There is an internal standard method which is obtained from the ratio of detected peak areas.

The analysis method of the present invention can be preferably used for quality control of resins. In order to perform quality control using the analysis method of the present invention, random sampling is performed from a lot of the heat-resistant resin produced and the weight of the product extracted by the extraction method of the present invention is measured or the soluble oligomer is analyzed by the analysis method. Of the specific soluble oligomer to be controlled is accumulated. From the quantitative data of soluble oligomers, it is possible to estimate the standard deviation of the population, estimate the average value of the population, etc. using the statistical quality control method, and to test the difference from the previously manufactured product. It can be performed. Furthermore, it is possible to create a control chart and manage the process so as to keep it stable.

[0026]

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited thereto.

In the examples and comparative examples described below,
A wholly aromatic polyester was used as the resin to be deposited. The
The wholly aromatic polyester is p-acetoxybenzoic acid 540.
g (3.00 mol), terephthalic acid 125 g (0.75 mol)
), 42 g (0.25 mol) of isophthalic acid, and
270 g (1.00) of 4,4'-diacetoxybiphenyl
(Mol) in a polymerization tank with a stirring blade and nitrogen gas atmosphere
The temperature is raised while stirring under the temperature, and the mixture is polymerized at 330 ° C for 1 hour.
It was Strong stirring while removing acetic acid by-produced during this period
Polymerized below. After that, the system was gradually cooled to obtain
The resin was discharged at 200 ° C. Crush the resulting resin
To obtain particles of 2.5 mm or less. This is the rotor
Treated in a re-kiln under nitrogen atmosphere at 290 ° C for 3 hours
By increasing the flow starting temperature, that is, 4 ° C./min.
Load the resin at a temperature rate of 100 kg / cm ²Under, inner diameter 1
mm when extruding from a nozzle with a length of 10 mm
Melt viscosity of 4800 Pa · sec (48,000 poise)
Particle-like wholly aromatic poly whose temperature at the point is 322 ° C
The ester was obtained.

The following conditions were used as the analysis conditions. Analytical condition 1 Liquid chromatograph HP-1100 type with mass detector manufactured by Hewlett-Packard Co.
-A column ODS type column is installed, 10 µl of an analytical sample solution containing a soluble oligomer is injected, and a column temperature of 40
The soluble oligomer is separated under a gradient elution condition described later at a temperature of 1.0 ° C. and a flow rate of 1.0 ml / min, and introduced into a mass detector equipped with an atmospheric pressure ion source connected to the chromatograph, and the ion is extracted in a negative ion mode. Was detected and mass spectrometry was performed.
The gradient elution conditions were as follows: the mobile phase was an aqueous solution of 0.1% acetic acid and an acetonitrile solution of 0.1% acetic acid, and 0 minutes, 10 minutes, 20 minutes, 35 minutes, and 40 minutes after the start of the gradient. , The ratio of 0.1% acetonitrile solution is 1 each
It was set to be 0%, 10%, 30%, 100%, 100%.

Analytical condition 2 Shimadzu Corporation high performance liquid chromatograph LC-10ATv
L-column ODS type column manufactured by Chemicals Evaluation and Research Institute is attached to p, and an analytical sample solution containing a soluble oligomer is 10 μm.
1 was injected to separate the soluble oligomer under the same gradient elution conditions as the analytical condition 1 at a column temperature of 40 ° C. and a flow rate of 1.0 ml / min, and an ultraviolet-visible detector SPD-10Avp connected to the chromatograph was used. Use, detection wavelength 254nm
It was detected at.

Example 1 2 g of the wholly aromatic polyester described above was filled in a stainless steel container having a volume of 11 ml, and a high-speed solvent extractor ASE-200 manufactured by Dionex Co. was used, and the pressure was 6.9 MP.
a, 2-propanol was introduced so that the temperature was 140 ° C., and the mixture was kept for 10 minutes to extract soluble oligomers. Then, the inside of the container was once returned to atmospheric pressure, 2-propanol was introduced again, and the mixture was held under the above conditions for 10 minutes, and then 2-propanol solution containing the soluble oligomer discharged from the SUS container by nitrogen purge ( About 3
(0 ml) was concentrated under reduced pressure, and tetrahydrofuran was added to 5 m.
The volume was adjusted to 1 and separated and analyzed under the above-mentioned analysis conditions 1.

In the obtained chromatogram, p-hydroxybenzoic acid and p-acetoxybenzoic acid were detected as soluble oligomers at retention times of 7.2 minutes and 26.8 minutes, respectively, but terephthalic acid, isophthalic acid, 4,4'-
Diacetoxybiphenyl was not detected. Further, after the retention time of 28 minutes, elution of soluble oligomers of dimers or more was observed. Of these, 28.0 minutes and 3
Regarding the two components eluted at 0.3 minutes, a dehydration condensation product of 1 molecule of p-hydroxybenzoic acid and 1 molecule of 4,4′-biphenyldiol (hereinafter referred to as oligomer 1), 2 molecules of p-hydroxybenzoic acid and 4 molecules , 4'-biphenyldiol 1
It was found to be a dehydration condensation product of molecules (hereinafter referred to as oligomer 2). The above-mentioned structural analysis of the eluted components was performed as follows. Regarding PHB, when an ion having a mass number of 137 was detected in a mass spectrum obtained under analysis condition 1 and a component detected at 7.4 minutes under analysis condition 2 and a standard substance of p-hydroxybenzoic acid were analyzed. The retention time was the same as the chromatograph of. Regarding p-acetoxybenzoic acid, it was carried out by detecting an ion having a mass number of 179 in the mass spectrum obtained under the analysis condition 1. Regarding the oligomer 1, it was carried out by detecting the ion of mass number 305 in the mass spectrum obtained under the analysis condition 1. Regarding the oligomer 2, it was carried out by detecting the ion having the mass number of 425 in the mass spectrum obtained under the analysis condition 1.

Quantification of the above-mentioned eluted components was carried out by an absolute calibration curve method using p-hydroxybenzoic acid as a standard substance.
It was calculated as the content per 1 g of the resin. The results are shown in Table 1.

Comparative Example 1 2 g of wholly aromatic polyester was added to a 100 ml round bottom flask, 100 ml of 2-propanol was added, and the mixture was extracted by the Soxhlet extraction method. After refluxing for 8 hours,
After the solution was concentrated under reduced pressure, the volume was adjusted to 5 ml with tetrahydrofuran, and detection was performed under the above-mentioned analysis condition 1. The results of the same quantitative analysis as in Example 1 are shown in Table 1.

[0034]

[Table 1] (Note 1) N. D. Indicates that all are less than 0.2 ppm by weight.

Comparative Example 2 The soluble polymer was extracted and quantitatively analyzed under the same conditions as in Example 1 except that n-hexane was used instead of 2-propanol used in Example 1. The results are shown in Table 1.

From the results shown in Table 1, in order to analyze the soluble oligomers contained in the wholly aromatic polyester, the Soxhlet extraction method under normal pressure, and even under pressure, other than carbon and hydrogen such as n-hexane can be obtained. In the method using a solvent containing no element (3), extraction was insufficient and satisfactory analysis values were not obtained, whereas in the method of the present invention, good analysis results could be obtained in a short time and easily.

[0037]

According to the method of the present invention, the softening temperature is 20.
Since the soluble oligomer in the resin at 0 ° C. or higher can be easily extracted and analyzed in a short time, the method of the present invention can be widely applied to fibers, films, molded products, elastomers, coating / coating materials, paints and the like. It can be suitably used for the development and quality control of heat-resistant resins used in, and is extremely useful industrially.

   ─────────────────────────────────────────────────── ─── Continued front page    F term (reference) 2G052 AA18 AB11 AD32 AD46 EB11                       ED03 ED09 GA11 GA17 GA24                       JA03                 4D056 AB20 AC04 AC06 AC07 AC08                       AC09 AC11 AC17 BA03 CA21                       CA28 DA01 DA02                 4H006 AA02 AD16 BB12 BB14 BB16                       BB17 BB20 BB21 BB24 BB25                       BC51 BC52 BJ50 BN30

Claims (8)

[Claims] 1. A method of extracting a soluble oligomer contained in a resin having a softening temperature of 200 ° C. or higher, using a solvent containing carbon, hydrogen and an element other than those, and having a temperature of 15 ° C. or higher and lower than a critical temperature of the solvent. And a temperature condition that is lower than the softening temperature of the resin, and under pressure condition, the method for extracting an oligomer from the resin. 2. A method for analyzing a soluble oligomer contained in a resin having a softening temperature of 200 ° C. or higher, which comprises the step of extracting the soluble oligomer by the extraction method according to claim 1, Oligomer analysis method. 3. The method according to claim 1, wherein the temperature condition is a temperature higher than the boiling point of the solvent at atmospheric pressure. 4. The method according to claim 1, wherein the pressurizing condition is a pressure of 3 MPa or more. 5. The solvent is acetone, methanol, ethanol, 2-propanol, tetrahydrofuran, dioxane, methylene chloride, chloroform, acetonitrile, N.
-The method according to any one of claims 1 to 4, which is a solvent containing at least one selected from the group consisting of methylpyrrolidone, dimethylformamide, pyridine, and ethyl acetate. 6. A resin which is a crushed resin.
The method described in any one of. 7. The resin selected from the group consisting of wholly aromatic polyester resins, aromatic polyether resins, polyether sulfone resins, polyether ether ketone resins, polyphenylene sulfide resins, polyimide resins, aramid resins and fluororesins. It is above, The method in any one of Claims 1-6. 8. A quality control method for a heat-resistant resin, which uses the method according to claim 1.