JP4742535B2 - Polyarylene sulfide oxide, solid article and method for producing the same - Google Patents

Description

  The present invention relates to a polyarylene sulfide oxide (hereinafter also referred to as PPSO) excellent in heat resistance, chemical resistance and moisture absorption resistance, and a method for producing the same. The polyarylene sulfide oxide of the present invention is a compound useful in a wide variety of industrial applications such as bag filters, various filters, and electrical materials that require moisture absorption resistance.

  Since polyarylene sulfide oxide has a high melting point and high chemical resistance, melt molding and solution molding are practically difficult, and in reality, molding after oxidation reaction treatment is difficult to adopt industrially. It was. From such a current situation, it can be said that it is very significant to make the polyarylene sulfide compound an article having the desired form before the oxidation reaction treatment, and to carry out the oxidation reaction treatment while maintaining the form to obtain the desired product in a desired form. .

Up to now, a method for oxidizing a polyarylene sulfide compound in the presence of a liquid is a method in which polyphenylene sulfide sulfone (hereinafter referred to as PPSS) is dissolved in concentrated sulfuric acid, and then hydrogen peroxide is dropped to oxidize (for example, Patent Documents 1 and 2), a method of dissolving polyphenylene sulfide (hereinafter referred to as PPS) in concentrated nitric acid and oxidizing (for example, refer to Patent Document 3), PPS with hydrogen peroxide or hypochlorite A method of oxidizing (for example, see Patent Document 4), a method of oxidizing PPS with peracetic acid or equilibrium peracetic acid prepared with hydrogen peroxide and acetic acid (for example, see Patent Documents 5 to 9), PPS with ozone There has been proposed a method (for example, see Patent Document 10) in which oxidation is performed by any of the techniques of Patent Documents 5 to 7 after oxidation.
British Patent No. 1234008 (pages 5-8) GB 1365486 (page 2-3) Japanese Patent Laid-Open No. 10-87998 (page 5) Japanese Patent Publication No. 60-35370 (page 5-8, Table I-III) Japanese Patent Laid-Open No. 10-87832 (page 3) JP 7-3027 A (page 6) Japanese Patent Laid-Open No. 5-230760 (page 3) JP 2000-328444 A (page 5-6, Table 1) JP-A-63-182413 (page 6-9) JP 7-3024 A (Page 6-7)

  However, the methods of Patent Documents 1 to 3 have a problem in that the polyarylene sulfide compound is once dissolved in the liquid and processed, so that the form before the oxidation reaction treatment cannot be maintained. On the other hand, the method of patent documents 4-10 is a method which can be processed, maintaining the form before an oxidation reaction process. However, for example, in the method of Patent Document 4, only a part of the surface layer of the article is oxidized, and the product is very brittle and cracks are generated. Moreover, although the method of patent documents 5-9 has described the example using the equilibrium peracetic acid formed from peracetic acid or the mixture of hydrogen peroxide and acetic acid for oxidation reaction, such a method is described simply. Only by the treatment, a polyarylene sulfide oxide having sufficient physical properties could not be obtained. Moreover, the polyarylene sulfide oxide obtained by the methods of Patent Documents 5 to 9 has a problem of high hygroscopicity. That is, there are essential problems such as a dimensional change of the solid article due to moisture absorption and a decrease in electrical characteristics of the solid article due to moisture absorption. As described above, in the methods proposed so far, there are many problems in the physical properties of the resulting polyarylene sulfide oxide and the production method thereof, and the methods have not been put to practical use. Accordingly, an object of the present invention is to provide a polyarylene sulfide oxide having excellent characteristics that can be satisfied for industrial use. Another object of the present invention is to produce this polyarylene sulfide oxide by a simple and efficient method that ensures process safety.

  As a result of intensive studies to solve these problems, the present inventors have found a polyarylene sulfide oxide having excellent characteristics that can be satisfied for industrial use. It has also been found that this polyarylene sulfide oxide can be produced by a simple and efficient method that ensures process safety.

That is, the present invention has a crystallinity of 30 % or more in the measurement of wide-angle X-ray diffraction, a heat of fusion in the measurement of a differential scanning calorimeter (DSC) of 15 J / g or less , and thermogravimetry (TGA). In the measurement, the polyarylene sulfide oxide has a residual carbide amount of 1% by weight or more .

  Moreover, this invention is a solid article which consists of said polyarylene sulfide oxide and has a form chosen from a powder, a fiber, a fabric, a film, and paper.

In the present invention, a solid article made of a polyarylene sulfide compound having a crystallinity of 50% or more in wide-angle X-ray diffraction measurement is maintained in the presence of a liquid containing 3 wt% to 10 wt% of an oxidizing agent. The crystallinity in wide-angle X-ray diffraction measurement is 30 % or more by performing an oxidation reaction treatment at a temperature of 50 ° C. to 70 ° C. for 2 hours or longer , and a differential scanning calorimeter (DSC) This is a method for producing a solid article for producing a solid article comprising a polyarylene sulfide oxide having a heat of fusion of 15 J / g or less in measurement and a residual carbide content of 1 wt% or more in measurement of thermogravimetric (TGA). .

  As described above, the polyarylene sulfide oxide is a compound useful for industrial use. According to the present invention, the polyarylene sulfide oxide is further excellent in high heat resistance, chemical resistance, moisture absorption resistance, electrical insulation, and the like. And solid articles useful for various industrial purposes can be obtained. In addition, the production method of the present invention is a method for producing a solid article made of polyarylene sulfide oxide having a desired shape by a simple and efficient method and using an industrially excellent method using a reagent that is easily available industrially. It is a manufacturing method to obtain. It can be said that it is significant to obtain the target oxide by an oxidation reaction treatment in a safe process while maintaining the form before oxidation.

The present invention is described in detail below.

<Polyarylene sulfide compound>
In the present invention, the polyarylene sulfide compound as a reaction raw material is represented by the general formula (1)

(R represents at least one of hydrogen, halogen, an aliphatic substituent substituted with an arbitrary functional group within an allowable range of valence, and an aliphatic substituent substituted with an aromatic substituent. ) Or a repeating unit represented by formula (2) to (8) having a repeating unit of 1.0 or less, preferably 0.3 or less, per mole of the repeating unit. )

(R represents hydrogen, halogen, an aliphatic substituent substituted with an arbitrary functional group within an allowable range of valence, or an aliphatic substituent substituted with an aromatic substituent, and R ′ represents Represents an aliphatic substituent substituted with an arbitrary functional group within an allowable range of valence.)).

  Substituents R and R ′ are preferably hydrogen or an aliphatic substituent having 1 to 4 carbon atoms. Specific examples include hydrogen, methyl group, ethyl group, n-propyl group, iso-propyl group, n-butyl group, Examples include iso-butyl group and tert-butyl group. Among these, a methyl group, an ethyl group, an iso-propyl group, and a tert-butyl group are preferable, and a methyl group is more preferable. Specific examples of the polyarylene sulfide compound include poly-p-phenylene sulfide, poly-p-tolylene sulfide, poly-p-chlorophenylene sulfide, poly-p-fluorophenylene sulfide, and the like. Poly-p-phenylene sulfide and poly-p-tolylene sulfide are preferable, and poly-p-phenylene sulfide is more preferable.

  Further, the solid article made of the polyarylene sulfide compound used in the present invention may be in any form such as powder, fiber, fabric, film, paper, and other molded articles. Specific examples of the fiber form include a thread wound around a bobbin, a skein, and the like. Specific examples of the fabric include a nonwoven fabric, a woven fabric, and a knitted fabric. It is particularly preferred that the solid article has a form selected from fibers, fabrics, films and paper. The solid article may contain various additives and other polymers as long as they do not interfere with the present invention.

Furthermore, the polyarylene sulfide compound constituting the solid article needs to have a crystallinity of 50 % or more . It is more preferably a weight average molecular weight (Mw) 30000 or more. The weight average molecular weight (Mw) is more preferably 40000 or more. As a conventional method, it has been known to use polyarylene sulfide having a low degree of crystallinity as a starting material in order to increase the treatment efficiency of the oxidation reaction treatment and shorten the reaction time. However, the inventors have rather high crystallinity, and by using a polyarylene sulfide compound having crystallinity and molecular weight in the specific range, the crystallinity and molecular weight are not impaired even in the oxidation reaction treatment. The physical properties of the resulting polyarylene sulfide oxide were found to be greatly improved. On the other hand, when polyarylene sulfide having a low crystallinity was used as a starting material, it was found that the crystallinity was further lowered by the subsequent oxidation reaction treatment, and as a result, the product was very brittle and greatly deteriorated physical properties. It was. Furthermore, it has been found that when the degree of crystallinity of the polyarylene sulfide before the reaction is high, the polymer molecules are regularly arranged, so that a crosslinking reaction is likely to occur. As the cross-linking proceeds, the physical properties of the resulting polyarylene sulfide oxide are further improved. A solid article made of polyarylene sulfide having such crystallinity and weight average molecular weight can be obtained, for example, by the following method.

  That is, using sodium hydrosulfide as a sulfur source and p-dichlorobenzene as an organic monomer, using sodium acetate as a polymerization aid during polymerization, the polymerization aid is 0.04 times mol or more with respect to sodium hydrosulfide. The polyphenylene sulfide having a weight average molecular weight (Mw) of 30,000 or more can be obtained by polymerization for about 4 hours under the condition that the excess of p-dichlorobenzene with respect to sodium hydrosulfide is 2.0 mol% or more.

Further, in order to obtain a solid article comprising a polyarylene sulfide compound having a crystallinity of 50 % or more, the method varies depending on the form of the solid article. For example, when the solid article is a fiber or a film, a known method is used. These can be obtained by controlling the stretching speed and stretching ratio, and controlling the heat treatment conditions after stretching.

  When the solid article is a fiber or a fabric, the thickness (single yarn fineness) of the fiber constituting the article is preferably 0.1 to 10 dtex, more preferably 0.5 to 9 dtex, still more preferably 1 to 7 dtex, Particularly preferred is 2.0 to 6.0 dtex.

<Reaction liquid>
In the present invention, the liquid used for the oxidation reaction treatment can be arbitrarily used as long as it maintains the form of the solid article made of the polyarylene sulfide compound, and uniformly dissolves the oxidizing agent used for the oxidation reaction treatment. It is preferable. Among these, a liquid containing an organic acid, an organic acid anhydride, or a mineral acid is preferable. Further, the liquid may be either alone or as a mixture. Also, water or a mixture containing water may be used. Specific examples of the liquid include water, acetone, methanol, ethanol, acetonitrile, tetrahydrofuran, chloroform, N-methylpyrrolidone, ethyl acetate, pyridine, organic acids and organic acid anhydrides described later. Specific examples of the organic acid include formic acid, acetic acid, trifluoroacetic acid, propionic acid, butyric acid, maleic acid and the like. As the organic acid anhydride, the following general formula (a)

(R ¹ and R ² each represent an aliphatic substituent having 1 to 5 carbon atoms, an aromatic substituent, or an aliphatic substituent substituted with an aromatic substituent, and R ¹ and R ² are And may be linked to form a cyclic structure.), And specific examples thereof include acetic anhydride, trifluoroacetic anhydride, propionic anhydride, butyric anhydride, maleic anhydride, and succinic anhydride. , Phthalic anhydride, benzoic anhydride, and anhydrous chlorobenzoic acid. Specific examples of the mineral acid include nitric acid, sulfuric acid, hydrochloric acid, phosphoric acid and the like. Preferred are water, acetic acid, trifluoroacetic acid, acetic anhydride, trifluoroacetic anhydride, sulfuric acid and hydrochloric acid, and more preferred are water, acetic acid, trifluoroacetic acid and sulfuric acid. Among them, particularly preferred is a liquid in which water, acetic acid and sulfuric acid are mixed. More preferable mixed composition ratios are: water: 5 to 20% by weight, acetic acid: 60 to 90% by weight, and sulfuric acid: 5 to 20% by weight, and give particularly good results at concentrations in this range.

<Oxidizing agent>
The oxidizing agent used in this reaction can be arbitrarily used as long as it dissolves uniformly in the liquid and gives a polyarylene sulfide oxide having the characteristics defined in the present invention. In particular, a combination of an oxidant and a liquid capable of subjecting a solid article made of polyarylene sulfide to an oxidation reaction treatment while maintaining its form is preferable. The oxidizing agent is preferably at least one selected from inorganic salt peroxides and hydrogen peroxide solutions, and is selected from one or more selected from inorganic salt peroxides and hydrogen peroxide solutions, and organic acids and organic acid anhydrides. Peroxides (including peracids) formed from a mixture of one or more of them may be used. Preferred examples of the inorganic salt peroxide used as the oxidizing agent include persulfates, perborates, and percarbonates. Here, examples of the salt include alkali metal salts, alkaline earth metal salts, ammonium salts, and the like, among which sodium salts, potassium salts, and ammonium salts are preferable. Specific examples thereof include sodium persulfate, potassium persulfate, ammonium persulfate as persulfates, sodium perborate, potassium perborate, ammonium perborate as perborate, and percarbonate as percarbonate. Examples thereof include sodium and potassium percarbonate. Specific examples of peracids formed from a mixture of hydrogen peroxide and an organic acid or organic acid anhydride include performic acid, peracetic acid, trifluoroperacetic acid, perpropionic acid, perbutyric acid, perbenzoic acid, and m-chloroperbenzoic acid. Of these, sodium persulfate, sodium perborate, performic acid, peracetic acid, and trifluoroperacetic acid are preferable, and sodium perborate, peracetic acid, and trifluoroperacetic acid are more preferable.

<Oxidant concentration>
The concentration of the oxidizing agent is important for safety management in the industrial production process. From the viewpoint of processing efficiency, a high concentration is preferable, but from the form and apparent volume of the solid article made of the polyarylene sulfide compound, the solid article is diluted with the liquid to a concentration that can be sufficiently immersed in the liquid containing the oxidizing agent, or It is possible to lower the concentration from the viewpoint of safety.

When using a peracid as an oxidizing agent, the concentration of the peracid is 3 to 10% by weight, more preferably 3 to 8% by weight. A good reaction result can be obtained at a concentration within this range, and a highly safe process can be constructed. If it is higher than this, its stability and safety are very sensitive to temperature. In particular, a high concentration of peracid exceeding 20% by weight is not preferable because it is difficult to control its stability and process safety. .

In addition, when inorganic salt peroxide is used as the oxidizing agent, it is optional to dilute with a solvent from the form or apparent volume of a solid article made of a polyarylene sulfide compound to a concentration that can be sufficiently immersed, or to reduce the concentration from a safety aspect. Is possible. Preferably they are 3 weight%-10 weight%, More preferably, they are 3 weight%-8 weight%.

  When a peracid or peroxide formed from a mixture of hydrogen peroxide and an organic acid is used, the concentration of the peracid or peroxide is preferably 10% by weight or less.

When a peracid or peroxide formed from a mixture of hydrogen peroxide and an organic acid anhydride is used, the concentration of the peracid or peroxide is preferably 3 to 15% by weight, particularly preferably 3%. % By weight to 8% by weight.

  When the concentration is within the above range, a particularly safe reaction result and a highly safe process can be constructed. If it is higher than this, its stability and safety are very sensitive to temperature. In particular, a high concentration of peracid exceeding 20% by weight is not preferable because it is difficult to control its stability and process safety. .

  For example, using a differential scanning calorimeter (DSC-60: Shimadzu Corporation), the sample amount is weighed within a range of 5 mg to 8 mg in an air atmosphere, and the temperature is measured in a stainless steel 4.9 MPa (50 atm) pressure-resistant sealed container. The thermal behavior of the peracetic acid solution when the program is set to 30 ° C to 200 ° C (temperature rise from 30 ° C to 200 ° C at a rate of 10 ° C / min) is decomposed in the case of 40% peracetic acid solution. The temperature is 110 ° C. and the calorific value is 770 J / g. In the case of equilibrium peracetic acid prepared by using equal amounts of acetic acid and 34.5% hydrogen peroxide water to a theoretical peracetic acid concentration of 40%, the decomposition temperature is 133 ° C. and the calorific value is 704 J / g. On the other hand, a liquid mixture prepared by using equal weight of acetic anhydride and 34.5% hydrogen peroxide solution to a theoretical peracetic acid concentration of 40% has a decomposition temperature of 132 ° C. and 445 J / g, which is about 60% of the calorific value. . The theoretical peracetic acid concentration of 9% is a decomposition temperature of 110 ° C. and 230 J / g, which is about one third of the calorific value, which is very small. Therefore, it is very important to ensure the safety of the oxidation reaction treatment process by reducing the oxidant concentration.

<Reaction temperature and time>
The oxidation treatment is not particularly limited as long as a polyarylene sulfide oxide having the characteristics defined in the present invention is obtained, but it is preferably performed at a temperature not higher than the boiling point of the liquid used. When the temperature is higher than the boiling point, the system is pressurized, the decomposition of the oxidant is often promoted and complicated equipment is required, and strict process management tends to be required in terms of safety. Specific oxidation reaction treatment temperature varies according to the boiling point of the liquid used, to the extent that the boiling point of the liquid is allowed, 50 ° C. to 70 ° C., especially preferred. For example, when the liquid is acetic acid, an oxidation reaction treatment temperature of 50 ° C. to 70 ° C. is preferable, and particularly good reaction results are obtained at temperatures in this range.

  The oxidation reaction treatment time is not particularly limited as long as the polyarylene sulfide oxide having the characteristics specified in the present invention can be obtained, and the specific time depends on the reaction temperature and the concentration of the oxidizing agent. For example, when the liquid is acetic acid, it is about 2 hours at 60 ° C. and 10 wt% oxidant concentration.

Usually, 2 to 8 hours are preferable under the conditions of 60 ° C. and 5% by weight of oxidizing agent. Further, when a peracid formed from a mixture of an acid anhydride represented by the general formula (a) and hydrogen peroxide is used as an oxidizing agent, the oxidation reaction treatment is efficiently performed in a short time while ensuring safety. It is preferable. For example, in the case of using equilibrium peracetic acid in which the theoretical peracetic acid concentration is adjusted to 40% using equal weight of acetic acid and 34.5% hydrogen peroxide water, any of the fiber bundles, fabrics, and felts is subjected to an oxidation reaction treatment. Is about 8 hours under a temperature condition of 60 ° C., whereas that of a mixed liquid prepared by using an equal weight of acetic anhydride and 34.5% aqueous hydrogen peroxide to a theoretical peracetic acid concentration of 40% is about 2 Time and very efficient.

<Oxidation reaction treatment method>
Although there is no restriction | limiting in particular in the processing system for performing this oxidation reaction process, The thing of batch type, continuous type, or those combination is also employable. Further, either a single-stage process or a multistage process can be employed.

  Here, the batch type means that a solid article composed of a polyarylene sulfide compound and a liquid containing an oxidant are charged into an arbitrary reaction vessel and subjected to an oxidation reaction treatment at an arbitrary concentration, temperature and time, and then polyarylene sulfide. It means a treatment system for taking out oxide or liquid. The continuous system means a system in which a solid article made of a polyarylene sulfide compound or a liquid containing an oxidizing agent is allowed to flow through a reaction vessel at an arbitrary flow rate and is subjected to an oxidation reaction treatment. In the continuous type, a solid article comprising a polyarylene sulfide compound fixed in an arbitrary form is subjected to an oxidation reaction treatment by circulating or circulating a liquid containing an oxidizing agent, or a liquid containing an oxidizing agent. Any method can be employed in which an arbitrary reaction vessel is charged and a solid article composed of a polyarylene sulfide compound is continuously circulated or circulated therethrough for an oxidation reaction treatment.

  Further, the multistage process means a process in which unit processes of oxidation reaction treatment adopting a batch type or a continuous type are constructed in a plurality or in stages. Specifically, the oxidation reaction treatment is divided into a plurality of times, and when each treatment is performed, a method of newly preparing a liquid containing an oxidant for performing the oxidation reaction treatment and performing the subsequent oxidation reaction treatment is exemplified. . Such a method is preferable in that the oxidation reaction can be promoted. Specifically, it is preferably used in that the oxidation reaction treatment time can be shortened and the reaction can be performed at a lower temperature. In particular, an oxidation reaction that can occur by diluting with a liquid so that it is sufficiently immersed or reducing the concentration to ensure safety, due to the effect of the form and apparent volume of a solid article made of a polyarylene sulfide compound This multi-stage process is preferable in that it can suppress the extension of processing time and eliminate the need for excessive temperature rise. By adopting this process, safety is ensured without extending the oxidation reaction time and temperature rise. Process construction.

  Further, the method for contacting the solid article comprising the polyarylene sulfide compound and the liquid containing the oxidizing agent in the oxidation reaction treatment is a method of immersing the solid article comprising the polyarylene sulfide compound in the liquid containing the oxidizing agent, Any method of spraying or spraying a liquid containing an oxidizing agent on a solid article composed of a polyarylene sulfide compound immobilized in a form can be employed.

  Next, the polyarylene sulfide oxide obtained by this reaction will be described.

<Polyarylene sulfide oxide>
By the oxidation reaction treatment described above, the thioether portion in the polyarylene sulfide compound is oxidized to obtain a polyarylene sulfide oxide. Furthermore, the oxidation reaction treatment according to a preferred embodiment not only oxidizes the thiol moiety in the polyarylene sulfide compound, but also causes crosslinking between the molecular chains of the polymer.

That is, the polyarylene sulfide oxide obtained by the present invention is
General formula (9)

(R ″ represents hydrogen, halogen, an aliphatic substituent substituted with an arbitrary functional group within an allowable range of valence, or an aliphatic substituent substituted with an aromatic substituent. R ″ may be linked to each other to form a crosslinked structure. R ″ may be a polymer chain made of polyarylene sulfide oxide. R ′ ″ is a polymer chain made of polyarylene sulfide oxide. M represents an integer of 0 to 3. X represents 0, 1, or 2), or the above repeating unit as a main structural unit And 1.0 mol or less, preferably 0.3 mol or less of the general formulas (10) to (16) per mol of the repeating unit.

(R ″ represents hydrogen, halogen, an aliphatic substituent substituted with an arbitrary functional group within an allowable range of valence, or an aliphatic substituent substituted with an aromatic substituent, and R ′ '' 'Represents an aliphatic substituent substituted with an arbitrary functional group within an allowable range of valence, and R or R ′ between molecules may be linked to each other to form a crosslinked structure. R ″ and R ″ ″ may be a polymer chain composed of polyarylene sulfide oxide. R ′ ″ represents a polymer chain composed of polyarylene sulfide oxide, and m is any one of 0 to 3. Represents an integer, n represents an integer of 0 to 2, and X represents 0, 1, or 2). Moreover, among the repeating units represented by the general formula (9), the ratio of the structural units in which X is 1 or 2 in the structural units in which X is 0, 1, or 2 is preferably 0.5 or more. More preferably, it is 0.7 or more.

<Residual carbide amount of polyarylene sulfide oxide>
The cross-linking generated in the oxidation reaction treatment process in the present invention means forming a bridge structure between polymer molecules in the process of oxidizing the polyarylene sulfide compound, and the carbon atom contained in the structure of the repeating unit, It means that atoms selected from either a sulfur atom or an oxygen atom are bonded to form a bridge structure. A part of the degree of crosslinking can be grasped by solid NMR analysis and thermogravimetric (TGA) measurement of the polyarylene sulfide oxide. In particular, in the TGA measurement, by measuring the amount of carbide remaining after the thermogravimetric change evaluation under a nitrogen atmosphere, it is possible to grasp the proportion of the crosslinked structure between carbon atoms in the crosslinked structure. For example, using a differential heat / thermogravimetric simultaneous measurement device (DTG-50: Shimadzu Corporation), a sample amount of about 10 mg is precisely weighed in a nitrogen atmosphere, and the temperature program is set to 30 ° C. to 900 ° C. on a platinum cell container. The amount of remaining carbide when measured by setting (from 30 ° C. to 900 ° C. at a rate of 10 ° C./min) is almost quantitatively determined by the PPS fiber (“Torcon (registered trademark)” manufactured by Toray Industries, Inc.). In the present invention, 13.2% by weight of carbide remains in the example of the PPSO fiber obtained after the oxidation reaction treatment, and a crosslinked structure of carbon atoms is formed by the oxidation reaction treatment, whereas the residue is not detected due to heat loss. Can be confirmed. In the present TGA measurement, the polyarylene sulfide oxide needs to have a residual carbide amount of 1% by weight or more , and particularly preferably has a residual carbide amount of 5% by weight or more. Within this range, it has particularly excellent characteristics regarding heat resistance and chemical resistance. The amount of residual carbide referred to here means the weight percent of the amount of residual carbide after measurement with respect to the weight of the polyarylene sulfide oxide before measurement in the thermogravimetric (TGA) measurement.

<PPSO crystallinity>
The polyarylene sulfide oxide obtained by the present invention has crystallinity. In other words, the crystallinity in the measurement of a wide angle X-ray diffraction of 30% or more, good Ri is preferably 50% or more. Within this range, the polyarylene sulfide oxide has particularly excellent characteristics with respect to physical properties. Here, the degree of crystallinity is a value calculated from the peak area ratio derived from the crystalline structure in the total diffraction peak area, which is observed in the wide-angle X-ray diffraction measurement. For example, using a wide-angle X-ray diffractometer (RINT2100: Rigaku), a peak area ratio derived from a crystalline structure when a film having a sample thickness of about 70 μm is measured with a Cu source (λ = 1.5406 Å). Can be calculated. In the present invention, as described above, the polyarylene sulfide to be subjected to the oxidation reaction treatment is a polyarylene sulfide having a relatively high crystallinity and molecular weight. It is possible to obtain a polyarylene sulfide oxide having crystallinity.

<PPSO infusibility>
Further, the polyarylene sulfide oxide has a heat of fusion of 15 J / g or less, preferably 10 J / g or less, more preferably 5 J / g or less, particularly preferably, as measured with a differential scanning calorimeter (DSC). It means a polyarylene sulfide oxide having a heat of fusion of 1 J / g or less, and more preferably a compound in which substantially no melting peak is observed. Within this range, it has particularly excellent characteristics regarding heat resistance and chemical resistance. Here, the DSC measurement conditions were as follows: a differential scanning calorimeter (RDC220: Seiko Instruments) at a nitrogen flow rate of 20 mL / min under a nitrogen atmosphere, and a temperature program of 30 ° C. to 500 ° C. within a sample amount of 5 mg to 10 mg. (Temperature rises from 30 ° C to 340 ° C at 10 ° C / min., Hold for 2 minutes, then drop to 30 ° C by 10 ° C / min. Temperature drop, hold for 2 minutes, then to 500 ° C at 10 ° C / min. It is the amount of heat of fusion when it is set and measured. Such a polyarylene sulfide oxide having a heat of fusion of 15 J / g or less can be produced by setting the oxidation reaction treatment conditions to the above-described preferred conditions.

<Use for PPSO>
The polyarylene sulfide oxide thus obtained has extremely high heat resistance and excellent chemical resistance against alkali, concentrated sulfuric acid and concentrated nitric acid. It is a useful compound and can be widely used for applications requiring heat resistance and chemical resistance. In addition, since it has excellent moisture absorption resistance, the dimensional change at the time of moisture absorption is small, and the electrical characteristics are not significantly reduced by moisture absorption, so that it can be widely used for electrical materials. Moreover, since the form before an oxidation reaction process is hold | maintained, the solid article of a desired shape can be obtained by shaping in a desired shape before an oxidation reaction process. Specifically, filter applications such as bag filters, chemical filters, food filters, chemical filters, oil filters, engine oil filters, air purification filters, paper applications such as electrical insulation paper, heat resistant work wear applications such as fire clothes, Dryer canvas, paper felt, sewing thread, heat-resistant felt, release material, battery separator, heart patch, artificial blood vessel, artificial skin, printed circuit board substrate, copy rolling cleaner, safety clothing, laboratory work clothes, warm clothing, difficulty It can be used for fuel clothing, ion exchange base materials, oil retaining materials, heat insulating materials, electrode separators, protective films, heat insulating materials for construction, cushion materials, liquid absorbent cores, brushes, and the like. Among them, filter applications, paper applications, heat resistant work wear applications are preferable, heat resistant bag filters as filter applications, electrical insulation paper as paper applications, fire fighting clothes as heat resistant work clothes applications, etc., but limited to these applications Is not to be done. These solid articles may contain various additives and other polymers as long as they do not interfere with the present invention.

  EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, this invention is not limited to this. The manufacturer grades of the reagents used here correspond to the first level.

(1) Differential scanning calorimetry (DSC) measurement conditions Using a differential scanning calorimeter (RDC220 (Seiko Instruments)), under a nitrogen atmosphere, a nitrogen flow rate of 20 mL / min, a sample amount of 5 mg is weighed, and a temperature program: 30 ° C. After raising the temperature from 10 to 340 ° C. at 10 ° C./min, hold for 2 minutes, lowering the temperature from 340 ° C. to 30 ° C. at 10 ° C./min, holding for 2 minutes, and then increasing from 30 ° C. to 500 ° C. at 10 ° C./min. The heat of fusion was measured from the DSC curve when warmed.

(2) Thermogravimetric (TGA) measurement conditions Using a differential thermal / thermogravimetric simultaneous measurement device (DTG-50 (Shimadzu Corporation)), weigh accurately about 10 mg of sample in a nitrogen atmosphere and place on a platinum cell container. Temperature program: Thermogravimetric change was measured from a TGA curve when the temperature was raised from 30 ° C. to 900 ° C. at 10 ° C./min. The weight percent of the remaining carbide after the measurement relative to the weight of the polyarylene sulfide oxide before the measurement was calculated and used as the amount of the remaining carbide.

(3) Wide-angle X-ray diffraction measurement conditions Using an X-ray diffractometer (RINT2100 (Rigaku)), X-ray diffraction was measured with a Cu source (λ = 1.5406 angstrom), and the total diffraction peak area observed The crystallinity was calculated from the peak area ratio (%) derived from the occupied crystalline structure.

(4) Evaluation conditions for chemical resistance A solid article made of a polyarylene sulfide compound or a solid article made of a polyarylene sulfide oxide subjected to an oxidation reaction is respectively 10% caustic soda water, 30% caustic soda water, 48% sulfuric acid water, The sample was immersed in concentrated sulfuric acid, 10% nitric acid, concentrated nitric acid (59% nitric acid) at 93 ° C. for 1 week, and the sample shape was observed when immersed and pinched with tweezers to evaluate chemical resistance. In addition, the judgment of chemical resistance is ○ mark when the shape is held both in the chemical solution and when pinched from the chemical solution with tweezers, the shape is held in the chemical solution, but the shape is broken when pinched with tweezers The case was marked with Δ, and the case of dissolving in a chemical solution was marked with ×, and the result was described.

(5) Electrical insulation measurement conditions: Measured according to the method of JIS standard K6911. In the case of volume resistivity, measurement was performed under a temperature condition near room temperature with a DC voltage of 100 V, a main electrode diameter of 50 to 70 mm, and an electrode load of 5 kgf. In the case of the dielectric breakdown strength, the measurement was performed under a temperature condition near room temperature at a main electrode diameter of 20 to 25 mm, an electrode load of 250 to 500 g, a power supply frequency of 60 Hz, and a voltage increase rate of about 0.2 to 1.0 kV / s.

(6) Weight average molecular weight measurement conditions The weight average molecular weight (GPC) was measured using the following apparatus, eluent and sample solution prepared by the operation and conditions.

1) Preparation of eluent Activated alumina (1/20 weight relative to 1-CN) was added to 1-chloronaphthalene (1-CN), stirred for 6 hours, and then filtered through a G4 glass filter. This was deaerated using an aspirator while applying an ultrasonic cleaner.

2) Sample solution preparation 5 mg of polymer and 5 g of 1-CN were weighed into a sample bottle. This was put into a high temperature filtration apparatus (SSC-9300 manufactured by Senshu Kagaku) set at 210 ° C. and heated for 5 minutes (1 minute preheating, 4 minutes stirring). The sample was removed from the high temperature filtration device and left to reach room temperature.

3) GPC measurement environment device: Senshu Science SSC-7100
Column name: Senshu Science GPC3506 × 1
Eluent: 1-chloronaphthalene (1-CN)
Detector: Differential refractive index detector Detector sensitivity: Range 8
Detector polarity: +
Column temperature: 210 ° C
Pre-temperature bath temperature: 250 ° C
Pump bath temperature: 50 ° C
Detector temperature: 210 ° C
Sample-side flow rate: 1.0 mL / min
Reference side flow rate: 1.0 mL / min
Sample injection amount: 300 μL
Calibration curve preparation sample: polystyrene.

(7) Hygroscopicity A solid article made of polyarylene sulfide oxide was treated in a high temperature and high humidity tank (20 ° C., 65 RH%) for 24 hours, and the moisture absorption rate was measured. The moisture absorption rate was calculated from [(weight after treatment−weight before treatment) / weight before treatment] × 100 (%).

Example 1
800 mL of acetic acid (manufactured by Kanto Chemical Co., Inc.) and 46.16 g (0.30 mmol; manufactured by Mitsubishi Gas Chemical Company) of sodium perborate tetrahydrate were put into a reaction vessel, and stirred at 60 ° C. for dissolution. Next, 4.03 g of poly-p-phenylene sulfide (PPS) fiber (“Torcon (registered trademark)” manufactured by Toray Industries, Inc .; fiber length: about 200 m, single yarn fineness: 4.5 dtex) was immersed in the reaction solution. The oxidation reaction treatment was performed at 60 ° C. for 10 hours. The weight of the fiber increased by 24.3% and 5.01 g of poly-p-phenylene sulfone (PPSO) fiber was obtained. In the differential scanning calorimeter (DSC) measurement, this fiber disappeared in the melting peak near the melting point (285 ° C.) of PPS, and no melting peak was observed at any observed temperature, and the fiber was an infusible fiber. . In addition, the chemical resistance was also excellent, and the shape was completely retained in all of the evaluation target chemicals in the chemical solution and when taken out from the chemical solution. Furthermore, as a result of measuring the thermogravimetric (TGA), the amount of remaining carbide was 10.2% by weight with respect to the PPSO fiber. The moisture absorption rate was about 5.1%. In addition, wide-angle X-ray diffraction was evaluated. As will be described later, the moisture absorption rate of the PPS fiber is about 0.8%, and the moisture absorption rate is relatively high due to the oxidation of the PPS fiber, but it has a sufficient level of moisture resistance in practical use.

Example 2
Instead of PPS fiber, 3.65 g of PPS fabric (“Torcon (registered trademark)” manufactured by Toray Industries, Inc .; size: 12.5 × 4.0 cm, single yarn fineness: 3.0 dtex) was used in the same manner as in Example 1. An oxidation reaction treatment was performed. The weight of the fabric increased by 29.0% to obtain a fabric composed of 4.71 g of PPS oxide (PPSO fabric). This fabric loses the melting point of PPS in DSC measurement, no melting peak is observed at any of the observed temperatures, is an infusible fabric, and has no substantial variation in size before and after treatment. Was retained. Further, the chemical resistance, the amount of residual carbides by TGA measurement, hygroscopicity and the like were also evaluated in the same manner as in Example 1.

Example 3
Instead of PPS fiber, PPS felt 4.79 g (“Torcon (registered trademark)” manufactured by Toray Industries, Inc .; size: 9.5 × 9.0 cm, single yarn fineness: 2.2 dtex) was used in the same manner as in Example 1. An oxidation reaction treatment was performed. The weight of the felt was increased by 30.5% to obtain 6.25 g of felt composed of PPS oxide (PPSO felt). In this felt, the melting point of the PPS fiber disappears in DSC measurement, the melting peak is not observed at any observed temperature, the felt is infusible, and there is no substantial change in size before and after the treatment. The form was retained. Further, the chemical resistance, the amount of residual carbides by TGA measurement, hygroscopicity and the like were also evaluated in the same manner as in Example 1.

Example 4
Instead of sodium perborate tetrahydrate, sodium perborate monohydrate (manufactured by Mitsubishi Gas Chemical Company) was used, and an oxidation reaction treatment was performed in the same manner as in Example 1. The weight of the fiber increased by 24.0% and a similar infusible PPSO fiber was obtained. Evaluation was performed in the same manner as in Example 1.

Example 5
The reaction time was shortened from 10 hours to 8 hours, and an oxidation reaction treatment was performed in the same manner as in Example 1. The fiber weight increased by 23.9%, yielding 4.99 g of PPSO fiber. This fiber was a substantially infusible fiber having a heat of fusion of 3.10 J / g at around 285 ° C. in a differential scanning calorimeter (DSC) measurement. In addition, the chemical resistance was also excellent, and the shape was completely retained in all of the evaluation target chemicals in the chemical solution and when taken out from the chemical solution. Furthermore, as a result of measuring thermogravimetry (TGA), the amount of remaining carbides was 7.6% by weight with respect to PPSO fiber. Wide-angle X-ray diffraction and hygroscopicity were also evaluated in the same manner as in Example 1.

Example 6
800 mL of acetic acid (manufactured by Kanto Chemical Co., Inc.) and 46.16 g (0.30 mmol; manufactured by Mitsubishi Gas Chemical Company) of sodium perborate tetrahydrate were put into a reaction vessel, and stirred and dissolved at 60 ° C. Next, 4.03 g of poly-p-phenylene sulfide (PPS) fiber (“Torcon (registered trademark)” manufactured by Toray Industries, Inc .; fiber length: about 20 m; single yarn fineness: 2.2 dtex) was immersed in the reaction solution. The oxidation reaction treatment was performed at 60 ° C. for 4 hours. The fiber weight increased by 18.4%, yielding 4.77 g of fiber. This fiber had a heat of fusion of 17.01 J / g at around 285 ° C. in a differential scanning calorimeter (DSC) measurement. Further, as in the first stage, 800 mL of acetic acid (manufactured by Kanto Chemical Co., Inc.) and 46.16 g of sodium perborate tetrahydrate (0.30 mmol; manufactured by Mitsubishi Gas Chemical Co., Inc.) were newly prepared in a reaction vessel. The fiber obtained in the first stage was immersed in the reaction solution and subjected to the second stage oxidation reaction treatment of multistage treatment at 60 ° C. for 4 hours. The fiber weight increased 24.3% relative to the initial PPS, yielding 5.01 g of poly-p-phenylene sulfoxide (PPSO) fiber. This fiber was an infusible fiber in which the melting peak near the melting point (285 ° C.) of the PPS fiber disappeared and no melting peak was observed at any observed temperature. In addition, the chemical resistance was also excellent, and the shape was completely retained in all of the evaluation target chemicals in the chemical solution and when taken out from the chemical solution. Furthermore, as a result of measuring thermogravimetry (TGA), the amount of remaining carbide was 12.7% by weight with respect to PPSO fiber. Further, the moisture absorption rate was as low as 5.1%. Further, wide-angle X-ray diffraction and the like were also evaluated in the same manner as in Example 1.

Comparative Example 1
The reaction time was shortened from 10 hours to 3 hours, and an oxidation reaction treatment was performed in the same manner as in Example 1. The fiber weight increased slightly by 4.7%, and further, the oxidation reaction proceeded sufficiently because it had a heat of fusion of 22.01 J / g near 285 ° C. in the differential scanning calorimeter (DSC) measurement. I understand that there is no. As for chemical resistance evaluation, although dissolved in concentrated nitric acid and retained in chemical solution in concentrated sulfuric acid, the shape is broken when pinched with tweezers. Both heat resistance and chemical resistance are It was inferior to that of the PPSO fiber which is the object of the invention. Furthermore, in thermogravimetric (TGA) measurement, the heat disappeared almost quantitatively and no residue was detected. Although the crystallinity is as high as 50%, the target oxidation reaction does not proceed sufficiently, and it can be said that this crystallinity represents the crystallinity of the PPS fiber. Therefore, the hygroscopicity was about 1.2%, indicating a low value for the PPS fiber.

Comparative Example 2
As a result of DSC measurement and chemical resistance evaluation of the PPS fiber described in Example 1 (“Torcon (registered trademark)” manufactured by Toray Industries, Inc.) under the same measurement or evaluation conditions as in the example, the fiber was 285. It has a heat of fusion of 37.10 J / g in the vicinity of ℃, and for chemical resistance evaluation, it dissolves in concentrated nitric acid and retains its shape in concentrated sulfuric acid but is pinched with tweezers. As a result, both heat resistance and chemical resistance were inferior to those of PPSO fiber. Furthermore, in the measurement of thermogravimetry (TGA), the heat disappeared almost quantitatively and no residue was detected. The moisture absorption was as low as about 0.8% for PPS fibers.
The results of Examples 1-6 and Comparative Examples 1-2 are shown in Table 1.

Example 7
Acetic acid 15.0 g (0.15 mol; manufactured by Wako Pure Chemical Industries, Ltd.) and 34.5% hydrogen peroxide water 5.0 g (0.05 mol; manufactured by Kanto Chemical Co., Inc.) were charged into the reaction vessel, and then room temperature (about 20 ° C.). The mixture was stirred until a homogeneous solution was obtained. Next, 69.3 mg of poly-p-phenylene sulfide (PPS) fiber (“Torcon (registered trademark)” manufactured by Toray Industries, Inc .; fiber length: about 2 m; single yarn fineness: 4.5 dtex) was immersed in the reaction solution. When oxidation treatment was performed at 60 ° C. The reaction was completed in 6 hours, and 88.1 mg of poly-p-phenylene sulfoxide (PPSO) fiber having a weight increase of 27.2% was obtained. In the differential scanning calorimeter (DSC) measurement, this fiber disappeared from the melting peak near the melting point (285 ° C.) of the PPS fiber, and no melting peak was observed at any of the observed temperatures. It was. Further, regarding the chemical resistance, the shape was completely maintained in all of the evaluation target chemicals in the chemical solution and at the time of taking out from the chemical solution. Furthermore, as a result of measuring thermogravimetry (TGA), the amount of remaining carbide was 13.2% by weight with respect to PPSO fiber. The moisture absorption rate was a low level of 5.2%. Wide-angle X-ray diffraction and the like were also evaluated in the same manner as in Example 1.

Example 8
The amounts of the oxidant and liquid were changed to 10.0 g of acetic acid (0.10 mol; manufactured by Wako Pure Chemical Industries, Ltd.) and 10.0 g (0.10 mol; manufactured by Kanto Chemical Co., Ltd.) of 34.5% hydrogen peroxide, 60 ° C. as in Example 7 using 71.2 mg of poly-p-phenylene sulfide (PPS) fiber (“Torcon (registered trademark)” manufactured by Toray Industries, Inc .; fiber length: about 2 m; single yarn fineness: 4.5 dtex) Oxidation reaction treatment was performed. The reaction was completed in 7 hours, and 89.2 mg of poly-p-phenylene sulfoxide (PPSO) fiber having a weight increase of 25.2% was obtained. This fiber is an infusible fiber in which the melting peak near the melting point (285 ° C.) of the PPS fiber disappears in any differential scanning calorimeter (DSC) measurement, and no melting peak is observed at any observed temperature. The chemical resistance was also excellent, and the shape was completely retained in all of the evaluation target chemicals in the chemical solution and at the time of removal from the chemical solution. Furthermore, as a result of measuring thermogravimetry (TGA), the amount of remaining carbide was 13.2% by weight with respect to PPSO fiber. Further, the moisture absorption rate was a low level of 5.1%. Wide-angle X-ray diffraction and the like were also evaluated in the same manner as in Example 1.

Example 9
Using acetic acid (manufactured by Kanto Chemical Co., Inc.), 20.0 g of a peracetic acid solution (peracetic acid 23.67 mmol; manufactured by Mitsubishi Gas Chemical Co., Ltd.) adjusted to a peracetic acid concentration of 8% by weight was charged into the reaction vessel, and Stir. Next, 70.6 mg of poly-p-phenylene sulfide (PPS) fiber (“Torcon (registered trademark)” manufactured by Toray Industries, Inc .; fiber length: about 2 m; single yarn fineness: 2.2 dtex) was immersed in the reaction solution. An oxidation reaction treatment was performed at 60 ° C. for 5 hours. The weight increased by 29.8% and 91.6 mg of poly-p-phenylene sulfoxide (PPSO) fiber was obtained. In the differential scanning calorimeter (DSC) measurement, this fiber disappeared in the melting peak near the melting point (285 ° C.) of PPS, and no melting peak was observed at any observed temperature, and the fiber was an infusible fiber. . In addition, the chemical resistance was also excellent, and the shape was completely retained in all of the evaluation target chemicals in the chemical solution and when taken out from the chemical solution. Furthermore, as a result of measuring thermogravimetry (TGA), the amount of remaining carbide was 12.8% by weight with respect to PPSO fiber. Further, the moisture absorption rate was a low level of 5.0%. Wide-angle X-ray diffraction and the like were also evaluated in the same manner as in Example 1.

Example 10
The peracetic acid concentration was changed to 3.6% by weight, and an oxidation reaction treatment was performed in the same manner as in Example 9. The weight of the fiber increased by 27.4% and a similar infusible PPSO fiber was obtained. Wide-angle X-ray diffraction and moisture absorption were also evaluated in the same manner as in Example 1.

Example 11
An oxidation reaction treatment was performed in the same manner as in Example 9 using a 50% by weight aqueous acetic acid solution and a peracetic acid / acetic acid aqueous solution adjusted to a peracetic acid concentration of 4.5% by weight. The weight of the fiber increased by 25.7% and a similar infusible PPSO fiber was obtained. Wide-angle X-ray diffraction and the like were also evaluated in the same manner as in Example 1.

Example 12
Instead of PPS fiber, 1.57 g of PPS felt (“Torcon (registered trademark)” manufactured by Toray Industries, Inc .; size: 8.9 × 3.2 cm; single yarn fineness: 3.0 dtex) was used in the same manner as in Example 9. An oxidation reaction treatment was performed. The weight of the felt increased by 31.2% to obtain 2.06 g of PPSO felt. In this felt, the melting point of the PPS fiber disappears in DSC measurement, the melting peak is not observed at any observed temperature, the felt is infusible, and there is no substantial change in size before and after the treatment. The form was retained. Further, the chemical resistance, the amount of residual carbides by TGA measurement, the moisture absorption rate, and the like were also evaluated in the same manner as in Example 1.

Example 13
Instead of the PPS fiber, 1.54 g of PPS film (“Torcon (registered trademark)” manufactured by Toray Industries, Inc .; size: 9.0 × 21.0 cm) was used, and an oxidation reaction treatment was performed in the same manner as in Example 9. The weight of the film increased by 27.1% to obtain 1.96 g of PPSO film. The melting point of the PPS film disappears in DSC measurement, the melting peak is not observed at any observed temperature, this film is an infusible film, and there is no substantial variation in size before and after processing. The form was retained. Further, the chemical resistance and the amount of residual carbides by TGA measurement were also evaluated in the same manner as in Example 1. Furthermore, as a result of wide-angle X-ray diffraction measurement, the peak area ratio derived from the crystalline structure in the total diffraction peak area of the PPSO film was 56%. Further, the moisture absorption was as low as 4.5%. From comparison with Examples 7-12, although hygroscopicity is low, it is thought that this is the difference by the surface area difference by the difference in a fiber form and a film form, ie, the difference by the contact area with a water | moisture content.

Example 14
Instead of PPS fiber, 5.95 g of PPS paper (“Torcon Paper (registered trademark)” manufactured by Toray Industries, Inc .; size: 20.0 cm × 36.0 cm × 100 μm) was used, and an oxidation reaction treatment was performed in the same manner as in Example 9. It was. The weight of the paper increased by 22.4% and 7.28 g of PPSO paper was obtained. This PPSO paper loses the melting point of the PPS paper in the DSC measurement, no melting peak is observed at any observed temperature, is an infusible paper, and has no substantial variation in size before and after processing. The shape was retained. Further, the chemical resistance and the amount of residual carbides by TGA measurement were also evaluated in the same manner as in Example 1. Further, the moisture absorption rate was as low as 5.7%. Furthermore, as a result of electrical insulation measurement, the volume resistivity was 1.3 × 10 ¹⁶ Ω · cm, and the dielectric breakdown strength was 6.4 kV / mm.

Further, it has been found that the present PPSO paper obtained by oxidizing PPS paper exhibits an effect as a paper application, particularly as an electrical insulating paper. Moreover, in order to show the feature of moisture and heat resistance, the electrical insulation was measured after moisture absorption treatment of this PPSO paper. As a result, the volume resistivity was 1.0 × 10 ¹⁶ Ω · cm, the dielectric breakdown strength was 5.4 kV / mm, and the decrease in electrical characteristics due to moisture absorption was small, indicating that the electrical characteristics could withstand practical use. .

Example 15
Using acetic acid (manufactured by Kanto Chemical Co., Inc.), 20.0 g of a peracetic acid solution (peracetic acid 23.67 mmol; manufactured by Mitsubishi Gas Chemical Co., Ltd.) adjusted to a peracetic acid concentration of 8% by weight was charged into the reaction vessel, and Stir. Next, 70.60 mg of poly-p-phenylene sulfide (PPS) fiber (“Torcon (registered trademark)” manufactured by Toray Industries, Inc .; fiber length: about 2 m, fiber thickness: 4.5 dtex) was immersed in the reaction solution. The first stage oxidation reaction treatment of multistage treatment was performed at 60 ° C. for 1 hour. The fiber weight increased by 13.0%, yielding 79.76 mg of poly-p-phenylene sulfide oxide fiber. This fiber had a heat of fusion of 15.90 J / g at around 285 ° C. in a differential scanning calorimeter (DSC) measurement. In the same manner as in the first stage, 20.0 g of peracetic acid solution (peracetic acid 23.67 mmol; manufactured by Mitsubishi Gas Chemical Company) was newly added using acetic acid (manufactured by Kanto Chemical Co., Ltd.) to adjust the peracetic acid concentration to 8 wt%. Next, the poly-p-phenylene sulfide oxide fiber obtained in the first stage is immersed in the reaction solution and subjected to the multistage second stage oxidation reaction treatment at 60 ° C. for 1 hour. It was. The fiber weight increased 29.6% relative to the initial PPS, yielding 91.53 mg of poly-p-phenylene sulfoxide (PPSO) fiber. This fiber was an infusible fiber in which the melting peak near the melting point (285 ° C.) of the PPS fiber disappeared and no melting peak was observed at any observed temperature. In addition, the chemical resistance was also excellent, and the shape was completely retained in all of the evaluation target chemicals in the chemical solution and when taken out from the chemical solution. Furthermore, as a result of measuring thermogravimetry (TGA), the amount of remaining carbides was 13.0% by weight with respect to PPSO fiber. Wide-angle X-ray diffraction and the like were also evaluated in the same manner as in Example 1.

Comparative Example 3
An oxidation reaction treatment was performed in the same manner as in Example 9 using a peracetic acid / acetic acid aqueous solution adjusted to 1.8% by weight with a 20% by weight acetic acid aqueous solution. The fiber weight increased by 12.4%. Since this fiber has a heat of fusion of 15.70 J / g at around 285 ° C. in a differential scanning calorimeter (DSC) measurement, the oxidation reaction does not proceed sufficiently and has an unreacted PPS structure. You can see that In addition, regarding chemical resistance evaluation, although dissolved in concentrated nitric acid and retained in chemical solution in concentrated sulfuric acid, the shape is broken when pinched with tweezers, and PPSO fiber has both heat resistance and chemical resistance. It was inferior to that. Wide-angle X-ray diffraction and the like were also evaluated in the same manner as in Example 1. Although the crystallinity is as high as 50%, the target oxidation reaction does not proceed sufficiently, and the crystallinity can be said to represent the crystallinity of the PPS fiber. Therefore, the moisture absorption rate was about 1.0%, which was a low value close to that of PPS fibers.
The results of Examples 7 to 15 and Comparative Example 3 are shown in Table 2.

Example 16
Acetic anhydride 15.0 g (0.15 mol; manufactured by Wako Pure Chemical Industries, Ltd.) and 34.5% hydrogen peroxide water 5.0 g (0.05 mol; manufactured by Kanto Chemical Co., Inc.) were charged into the reaction vessel, and then room temperature (about 20 ° C. ) Until a uniform solution is obtained. Next, 68.6 mg of poly-p-phenylene sulfide (PPS) fiber (“Torcon (registered trademark)” manufactured by Toray Industries, Inc .; fiber length: about 2 m; single yarn fineness: 4.5 dtex) was immersed in the reaction solution. The oxidation reaction treatment was performed at 60 ° C. The reaction was completed in 2 hours, and 85.4 mg of poly-p-phenylene sulfoxide (PPSO) fiber having a weight increase of 24.4% was obtained. In the differential scanning calorimeter (DSC) measurement, this fiber disappeared from the melting peak near the melting point (285 ° C.) of the PPS fiber, and no melting peak was observed at any of the observed temperatures. It was. In addition, the chemical resistance was also excellent, and the shape was completely retained in all of the evaluation target chemicals in the chemical solution and when taken out from the chemical solution. Furthermore, as a result of measuring thermogravimetry (TGA), the amount of remaining carbide was 13.2% by weight with respect to PPSO fiber. Wide-angle X-ray diffraction and the like were also evaluated in the same manner as in Example 1.

Example 17
The weight of acetic anhydride was changed to 10.0 g (0.10 mol; manufactured by Wako Pure Chemical Industries, Ltd.), and the weight of 34.5% hydrogen peroxide water was changed to 10.0 g (0.10 mol; manufactured by Kanto Chemical Co., Inc.). The oxidation reaction treatment was performed in the same manner as described above. The reaction was completed in 3 hours, and a similar infusible PPSO fiber having a weight increase of 26.0% was obtained and evaluated in the same manner as in Example 1.

Example 18
The weight of acetic anhydride was changed to 17.5 g (0.17 mol; manufactured by Wako Pure Chemical Industries, Ltd.) and the weight of 34.5% hydrogen peroxide water was changed to 2.5 g (0.025 mol; manufactured by Kanto Chemical Co., Inc.). The oxidation reaction treatment was performed in the same manner as described above. The reaction was completed in 5 hours, and a similar infusible PPSO fiber having a weight increase of 26.6% was obtained and evaluated in the same manner as in Example 1.

Example 19
Instead of PPS fibers, 65.1 mg of PPS fabric (“Torcon (registered trademark)” manufactured by Toray Industries, Inc .; size: 1.0 cm × 1.0 cm, single yarn fineness: 4.5 dtex) was used in the same manner as in Example 16. An oxidation reaction treatment was performed. The reaction was completed in 2 hours, and 83.6 mg of PPSO fabric having an increased weight of 28.4% was obtained. This fabric loses the melting point of PPS in DSC measurement, no melting peak is observed at any of the observed temperatures, is an infusible fabric, and has no substantial variation in size before and after treatment. Was retained. Further, the chemical resistance, the amount of residual carbides by TGA measurement, the moisture absorption rate, and the like were also evaluated in the same manner as in Example 1.

  The PPSO fabric obtained by oxidizing the present PPS fabric exhibited an effect as a filter, particularly a bag filter utilizing infusibilities, and a high effect as a heat-resistant work wear, particularly as a fire fighting suit.

Example 20
In the same manner as in Example 16, using 65.3 mg of PPS felt (“Torcon (registered trademark)” manufactured by Toray Industries, Inc .; size: 0.5 cm × 1.0 cm, single yarn fineness: 4.5 dtex) instead of the PPS fiber. An oxidation reaction treatment was performed. The reaction was completed in 2 hours, and 84.9 g of PPSO felt having a weight increase of 30.1% was obtained. This felt is a felt in which the melting point of PPS disappears in DSC measurement, no melting peak is observed at any observed temperature, is infusible felt, and has no substantial variation in size before and after processing. Was retained. Further, the chemical resistance, the amount of residual carbides by TGA measurement, the moisture absorption rate, and the like were also evaluated in the same manner as in Example 1. The PPSO felt obtained by oxidizing this PPS felt exhibited a high effect as a filter, particularly as a bag filter utilizing infusibilities, and as a heat-resistant work wear, particularly as a fire fighting suit.

Example 21
Instead of PPS fiber, 5.95 g of PPS paper (“Torcon Paper (registered trademark)” manufactured by Toray Industries, Inc .; size: 20.0 cm × 36.0 cm × 100 μm) was used, and an oxidation reaction treatment was performed in the same manner as in Example 16. It was. The reaction was completed in 2 hours, the weight increased by 23.4%, and 7.34 g of PPSO paper was obtained. This PPSO paper is a paper in which the melting point of the PPS fiber disappears in DSC measurement, no melting peak is observed at any observed temperature, is infusible, and has no substantial variation in size before and after the treatment. The shape was retained. Further, the chemical resistance was the same as in Example 16, and the moisture absorption rate was 5.4%. Wide-angle X-ray diffraction was also evaluated in the same manner as in Example 1. Furthermore, as a result of electrical insulation measurement, the volume resistivity was 1.2 × 10 ¹⁶ Ω · cm, and the dielectric breakdown strength was 6.0 kV / mm. In addition, as a result of measuring the electrical insulation after moisture absorption treatment of this PPSO paper, the volume resistivity is 1.0 × 10 ¹⁶ Ω · cm, the dielectric breakdown strength is 5.5 kV / mm. It turned out to be small and practical.

  Further, the present PPSO paper obtained by oxidizing PPS paper exhibited a high effect as a paper application, particularly as an electric insulating paper for a motor.

Example 22
The acetic anhydride was changed to 15.0 g of propionic anhydride (0.12 mol; manufactured by Tokyo Chemical Industry Co., Ltd.), and an oxidation reaction treatment was performed in the same manner as in Example 16. The reaction was completed in 10 hours, and a similar infusible PPSO fiber having a weight increase of 26.0% was obtained and evaluated in the same manner as in Example 1.
Table 3 shows the results of Examples 16 to 22 and the results of Comparative Example 2 for reference.

Example 23
111 g of acetic acid (1.85 mol; manufactured by Kanto Chemical Co., Inc.) and 37.0 g of 34.5% hydrogen peroxide water (0.38 mol; manufactured by Kanto Chemical Co., Inc.) were charged into the reaction vessel and stirred at room temperature (about 20 ° C.). did. Next, 19.8 g of PPS staple fiber (“Torcon (registered trademark)” manufactured by Toray Industries, Inc .; single yarn fineness: 2.2 dtex) was immersed in the reaction solution and heated to 60 ° C., followed by 95% sulfuric acid 10. 0 g (0.1 mol; manufactured by Kanto Chemical Co., Inc.) was slowly dropped over 30 minutes to carry out an oxidation reaction treatment. The reaction was completed in 2 hours after the completion of the dropping, and 25.8 g of poly-p-phenylene sulfoxide (PPSO) staple fiber having an increased weight of 30.3% was obtained. In the staple fiber, the melting peak near the melting point (285 ° C.) of the PPS fiber disappears in the differential scanning calorimeter (DSC) measurement, and no melting peak is observed at any observed temperature, and the staple fiber is an infusible fiber. there were. In addition, the chemical resistance was also excellent, and the shape was completely retained in all of the evaluation target chemicals in the chemical solution and when taken out from the chemical solution. Furthermore, as a result of measuring the thermogravimetric (TGA), the amount of remaining carbide was 13.3% by weight with respect to the PPSO fiber. Further, the moisture absorption rate was as low as 5.2%. Wide-angle X-ray diffraction and the like were also evaluated in the same manner as in Example 1.

Example 24
In place of PPS staple fibers, 20.1 g of PPS felt (“Torcon (registered trademark)” manufactured by Toray Industries, Inc .; size 15 cm × 20 cm, single yarn fineness: 3.0 dtex) was used, and an oxidation reaction treatment was performed in the same manner as in Example 23. went. The reaction was completed in 2 hours to obtain 25.9 g of PPSO felt with an increase of 28.9% in weight. This felt is a felt in which the melting point of PPS disappears in DSC measurement, no melting peak is observed at any observed temperature, is infusible felt, and has no substantial variation in size before and after processing. Was retained. Further, the chemical resistance, the amount of residual carbides by TGA measurement, the moisture absorption rate, and the like were also evaluated in the same manner as in Example 1.

Example 25
In the same manner as in Example 23, 4.73 g of PPS fabric (“Torcon (registered trademark)” manufactured by Toray Industries, Inc .; size: 12.5 cm × 5.0 cm, single yarn fineness: 3.0 dtex) was used instead of the PPS fiber. An oxidation reaction treatment was performed. The reaction was completed in 2 hours, the weight increased by 23.5%, and 5.84 g of PPSO fabric was obtained. The melting point of the PPS fiber disappears in DSC measurement, the melting peak is not observed at any of the observed temperatures, the fabric is an infusible fabric, and has no substantial variation in size before and after the treatment. The form was retained. Further, the chemical resistance, the amount of residual carbides by TGA measurement, the moisture absorption rate, and the like were also evaluated in the same manner as in Example 1.

Example 26
Instead of PPS fibers, PPS paper 4.49 g (“Torcon Paper (registered trademark)” manufactured by Toray Industries, Inc .; size: 20.0 cm × 34.0 cm × 100 μm) was used, and an oxidation reaction treatment was performed in the same manner as in Example 23. It was. The reaction was completed in 2 hours, the weight increased by 22.5%, and 5.50 g of PPSO paper was obtained. This PPSO paper is a paper in which the melting point of the PPS fiber disappears in DSC measurement, no melting peak is observed at any observed temperature, is infusible, and has no substantial variation in size before and after the treatment. The shape was retained. Further, the chemical resistance, the amount of residual carbides by TGA measurement, the moisture absorption rate, and the like were also evaluated in the same manner as in Example 1. The moisture absorption rate was 5.3%. Furthermore, as a result of electrical insulation measurement, the volume resistivity was 3.5 × 10 ¹⁴ Ω · cm, and the dielectric breakdown strength was 6.0 kV / mm. As a result of measuring the electrical insulation after moisture absorption treatment of this PPSO paper, the volume resistivity is 2.0 × 10 ¹⁴ Ω · cm, the dielectric breakdown strength is 5.3 kV / mm, and the deterioration of the electrical characteristics due to moisture absorption is small. I understood it.

Example 27
The amounts of the oxidizing agent and the liquid used were 120 g of acetic acid (2.0 mol; manufactured by Kanto Chemical Co., Inc.), 38.0% hydrogen peroxide solution 18.0 g (0.18 mol; manufactured by Kanto Chemical Co., Ltd.), 95% sulfuric acid 20. In place of 0 g (0.2 mol; manufactured by Kanto Chemical Co., Inc.), an oxidation reaction treatment was performed in the same manner as in Example 23 using 20.1 g of PPS staple fibers (“Torcon (registered trademark)” manufactured by Toray Industries, Inc.). The reaction was completed in 3 hours, and 26.1 g of PPSO staple fibers having a weight increase of 30.0% were obtained. This staple fiber has a melting point of PPS disappeared by DSC measurement, no melting peak is observed at any observed temperature, is an infusible felt, and has no substantial variation in size before and after the treatment. The form was retained. Further, the chemical resistance, the amount of residual carbides by TGA measurement, the moisture absorption rate, and the like were also evaluated in the same manner as in Example 1.
The results of Examples 23 to 27 are shown in Table 4.

<Production of poly-p-phenylene sulfide resin>
Reference example 1
In a 70 liter autoclave equipped with a stirrer, 8267.0 g (70.0 mol) of 47.5% sodium hydrosulfide, 2975.0 g (71.4 mol) of 96% sodium hydroxide, N-methyl-2-pyrrolidone (NMP ) 11434.5 g (115.5 mol), 516.6 g (6.3 mol) sodium acetate, and 10500.0 g of ion-exchanged water, gradually heated to 230 ° C. over about 3 hours while passing nitrogen at normal pressure After distilling 14770.0 g of water and 280.0 g of NMP, the reaction vessel was cooled to 160 ° C. The residual water content in the system per 1 mol of the charged alkali metal sulfide was 1.08 mol including the water consumed for the hydrolysis of NMP. The amount of hydrogen sulfide scattered was 0.017 mol per mol of the alkali metal sulfide charged.

  Next, 10347.6 g (70.4 mol) of p-dichlorobenzene (p-DCB) and NMP9064.4 g (91.6 mol) were added, the reaction vessel was sealed under nitrogen gas, and the mixture was stirred at 240 rpm. The temperature was raised from 200 ° C. to 270 ° C. at a rate of 0.6 ° C./min and held at 270 ° C. for 140 minutes.

  After 140 minutes at 270 ° C., 2646.0 g (147.0 mol) of ion-exchanged water was injected into the reaction system over 15 minutes, and then cooled to 250 ° C. Next, it was cooled to 200 ° C. at a rate of 1.0 ° C./min, and then rapidly cooled to near room temperature.

  The contents were taken out, diluted with 35 liters of NMP, the solvent and solids were filtered off with a sieve (80 mesh), and the resulting particles were washed several times with 70 liters of warm water and filtered off. This was dried with hot air at 80 ° C. and dried under reduced pressure at 120 ° C. to obtain polyphenylene sulfide. The weight average molecular weight (Mw) of the polyphenylene sulfide at this time was Mw = 40,000 as a result of GPC measurement.

Reference example 2
As a result of carrying out in the same manner as in Reference Example 1 except that the amount of sodium acetate was 229.6 g (2.8 mol), polyphenylene sulfide having a weight average molecular weight Mw = 30,000 was obtained.

<Preparation of poly-p-phenylene sulfide resin composition (preparation of pellets before film production)>
Reference example 3
A slurry was prepared by finely dispersing 50% by weight of spherical calcite-type calcium carbonate having an average particle diameter of 1.0 μm in ethylene glycol. This slurry was filtered through a 1 μm cut filter, and then mixed with the poly-p-phenylene sulfide powder produced in Reference Example 1 or Reference Example 2 using a Henschel mixer so that the calcium carbonate would be 5.0 wt%. Next, the mixture was supplied to a twin screw extruder having two vent holes, and ethylene glycol was removed from the vent holes simultaneously with melt kneading, extruded into a gut shape, cooled in water, and then cut into particle pellets.

  Moreover, only the poly-p-phenylene sulfide powder produced in Reference Example 1 or Reference Example 2 was melt-extruded in the same manner as described above to obtain particle-free pellets.

<Preparation of poly-p-phenylene sulfide film>
Reference example 4
The particle pellets and non-particle pellets prepared in Reference Example 3 were mixed so that the calcium carbonate would be 0.4% by weight. Particle pellets and non-particle pellets were combined in the same weight average molecular weight. Crystallized pellets were processed in a rotary vacuum dryer at 150 ° C. under reduced pressure of 3 mmHg (400 Pa) for 3 hours. Next, this crystallization pellet is supplied to a 90 mm diameter single screw extruder, passed through a filter having a melting temperature of 330 ° C. and a filtration accuracy of 10 μm, and discharged from a stainless steel T die having a lip width of 400 mm and a slit gap of 1.5 mm. The film was cooled and solidified on a metal drum whose surface was kept at 30 ° C. to obtain an amorphous film having a thickness of 650 μm. Next, the amorphous film is wound around a rotating roll group having a surface temperature of 95 ° C. and heated, and subsequently stretched 3.5 times in the machine direction (MD) of the film with a roll having a surface temperature of 25 ° C. did. Next, the film was stretched 3.5 times in the lengthwise and direct direction (TD) of the film in a room where hot air of 100 ° C. circulates in a tenter, and then subjected to a constant length heat treatment for 10 seconds in a room where hot air of 280 ° C. circulates 3.0% limited shrinkage was performed in the width direction at a temperature of 200 ° C. to obtain a poly-p-phenylene sulfide film having a thickness of 50 μm.

  The degree of crystallinity of the films measured by wide-angle X-ray diffraction was 68%, and the weight average molecular weight was not different from that of the poly-p-phenylene sulfide powder prepared in Reference Example 1 or Reference Example 2.

Reference Example 5
Using only the non-particle pellets produced in Reference Example 3, it was supplied to a 90 mmφ single screw extruder in the same manner as in Reference Example 4, passed through a filter having a melting temperature of 330 ° C. and a filtration accuracy of 10 μm, and a lip width of 400 mm, It was discharged from a stainless steel T-die having a slit gap of 1.5 mm and cooled and solidified on a metal drum whose surface was kept at 30 ° C. to obtain an amorphous film having a thickness of 650 μm. Next, the amorphous film is wound around a rotating roll group having a surface temperature of 95 ° C. and heated, and subsequently stretched 3.5 times in the machine direction (MD) of the film with a roll having a surface temperature of 25 ° C. did. Next, the film was stretched 3.5 times in the lengthwise and direct direction (TD) of the film in a room where hot air of 100 ° C. circulates in a tenter, and then subjected to a constant length heat treatment for 10 seconds in a room where hot air of 280 ° C. circulates 3.0% limited shrinkage was performed in the width direction at a temperature of 200 ° C. to obtain a poly-p-phenylene sulfide film having a thickness of 50 μm.

  The crystallinity of the films measured by wide-angle X-ray diffraction was 65%, and the weight average molecular weight was not different from that of the poly-p-phenylene sulfide powder prepared in Reference Example 1 or Reference Example 2.

<Preparation of poly-p-phenylene sulfide fiber>
Reference Example 6
Using the particle-free pellets prepared in Reference Example 3, the fineness is obtained by discharging from the die at a melting temperature of 320 ° C., a discharge rate of 350 g / min, and a drawing speed of 800 m / min, and dropping and cooling the atmosphere maintained at 23 ° C. An undrawn yarn of 4375 dtex was obtained. Next, the undrawn yarn was wound around a rotating roll group having a surface temperature of 98 ° C. and heated, and drawn at a draw ratio of 3.27 and a draw speed of 120 m / min. Next, it is crimped at a crimping degree of 13.0 with a crimper having a surface temperature of 90 ° C., then heat-treated by passing it through an atmosphere maintained at 125 ° C., and then cooled and cut. Thus, poly-p-phenylene sulfide fiber having a single yarn fiber of 2.2 dtex and a length of 50 mm to 80 mm was obtained.

  The degree of crystallinity of the fibers measured by wide-angle X-ray diffraction was 55%, and the weight average molecular weight was not different from that of the poly-p-phenylene sulfide powder prepared in Reference Example 1 or Reference Example 2.

Example 28
The oxidation reaction treatment was carried out in the same manner as in Example 1 using 4.03 g of poly-p-phenylene sulfide (PPS) fiber having a weight average molecular weight Mw of 40,000 and a crystallinity of 55% prepared in Reference Example 6. . The weight of the fiber increased by 24.3% and 5.01 g of poly-p-phenylene sulfone (PPSO) fiber was obtained. In the differential scanning calorimeter (DSC) measurement, this fiber disappeared in the melting peak near the melting point (285 ° C.) of PPS, and no melting peak was observed at any observed temperature, and the fiber was an infusible fiber. . In addition, the chemical resistance was also excellent, and the shape was completely retained in all of the evaluation target chemicals in the chemical solution and when taken out from the chemical solution. Furthermore, as a result of measuring the thermogravimetric (TGA), the amount of remaining carbide was 10.2% by weight with respect to the PPSO fiber, and the crystallinity by wide-angle X-ray diffraction measurement was 45%.

Example 29
The oxidation reaction treatment was carried out in the same manner as in Example 7 using 69.3 mg of poly-p-phenylene sulfide (PPS) fiber having a weight average molecular weight Mw of 40,000 and a crystallinity of 55% prepared in Reference Example 6. . The fiber weight increased by 27.2%, yielding 88.1 mg of poly-p-phenylenesulfone (PPSO) fiber. In the differential scanning calorimeter (DSC) measurement, this fiber disappeared in the melting peak near the melting point (285 ° C.) of PPS, and no melting peak was observed at any observed temperature, and the fiber was an infusible fiber. . In addition, the chemical resistance was also excellent, and the shape was completely retained in all of the evaluation target chemicals in the chemical solution and when taken out from the chemical solution. Furthermore, as a result of measuring the thermogravimetric (TGA), the amount of remaining carbide was 13.2% by weight with respect to the PPSO fiber, and the crystallinity by wide-angle X-ray diffraction measurement was 45%.

Example 30
The oxidation reaction treatment was performed in the same manner as in Example 29 except that the poly-p-phenylene sulfide (PPS) fiber having a weight average molecular weight Mw = 30,000 and a crystallinity of 55% was used. The fiber weight increased by 28.2%, yielding 88.8 mg of poly-p-phenylenesulfone (PPSO) fiber. In the differential scanning calorimeter (DSC) measurement, this fiber disappeared in the melting peak near the melting point (285 ° C.) of PPS, and no melting peak was observed at any observed temperature, and the fiber was an infusible fiber. . In addition, the chemical resistance was also excellent, and the shape was completely retained in all of the evaluation target chemicals in the chemical solution and when taken out from the chemical solution. Further, as a result of measuring the thermogravimetric (TGA), the amount of remaining carbide was 12.8% by weight with respect to the PPSO fiber, and the crystallinity by wide-angle X-ray diffraction measurement was 43%. Further, the moisture absorption rate was as low as 5.2%.

Example 31
The oxidation reaction treatment was carried out in the same manner as in Example 16 using 68.6 mg of poly-p-phenylene sulfide (PPS) fibers having a weight average molecular weight Mw of 40,000 and a crystallinity of 55% prepared in Reference Example 6. . The fiber weight increased by 24.4%, yielding 85.4 mg of poly-p-phenylenesulfone (PPSO) fiber. In the differential scanning calorimeter (DSC) measurement, this fiber disappeared in the melting peak near the melting point (285 ° C.) of PPS, and no melting peak was observed at any observed temperature, and the fiber was an infusible fiber. . In addition, the chemical resistance was also excellent, and the shape was completely retained in all of the evaluation target chemicals in the chemical solution and when taken out from the chemical solution. Further, as a result of measuring the thermogravimetric (TGA), the amount of remaining carbide is 14.3% by weight with respect to the PPSO fiber, the crystallinity is 44% by the wide angle X-ray diffraction measurement, and the moisture absorption is 5.0. % And a low value.

Example 32
The oxidation reaction treatment was performed in the same manner as in Example 31 except that the poly-p-phenylene sulfide (PPS) fiber having a weight average molecular weight Mw = 30,000 and a crystallinity of 55% was used. The fiber weight increased by 25.7%, yielding 86.2 mg of poly-p-phenylenesulfone (PPSO) fiber. In the differential scanning calorimeter (DSC) measurement, this fiber disappeared in the melting peak near the melting point (285 ° C.) of PPS, and no melting peak was observed at any observed temperature, and the fiber was an infusible fiber. . In addition, the chemical resistance was also excellent, and the shape was completely retained in all of the evaluation target chemicals in the chemical solution and when taken out from the chemical solution. Furthermore, as a result of measuring the thermogravimetric (TGA), the amount of remaining carbide is 12.7% by weight with respect to the PPSO fiber, the crystallinity by the wide-angle X-ray diffraction measurement is 42%, and the moisture absorption is 5.3. % Was a low value.

Example 33
The oxidation reaction treatment was performed in the same manner as in Example 23 using 19.8 g of poly-p-phenylene sulfide (PPS) fibers having a weight average molecular weight Mw of 40,000 and a crystallinity of 55%, which were prepared in Reference Example 6. . The weight of the fiber increased by 30.3% and 25.8 g of poly-p-phenylene sulfone (PPSO) fiber was obtained. In the differential scanning calorimeter (DSC) measurement, this fiber disappeared in the melting peak near the melting point (285 ° C.) of PPS, and no melting peak was observed at any observed temperature, and the fiber was an infusible fiber. . In addition, the chemical resistance was also excellent, and the shape was completely retained in all of the evaluation target chemicals in the chemical solution and when taken out from the chemical solution. Furthermore, as a result of measuring the thermogravimetric (TGA), the amount of remaining carbide was 13.3% by weight with respect to the PPSO fiber, the crystallinity was 44% and the moisture absorption was 5.2% by wide-angle X-ray diffraction measurement. Met.

Example 34
The oxidation reaction treatment was performed in the same manner as in Example 33 except that the poly-p-phenylene sulfide (PPS) fiber having a weight average molecular weight Mw = 30,000 and a crystallinity of 55% was used. The weight of the fiber increased by 29.2% and 25.6 g of poly-p-phenylene sulfone (PPSO) fiber was obtained. In the differential scanning calorimeter (DSC) measurement, this fiber disappeared in the melting peak near the melting point (285 ° C.) of PPS, and no melting peak was observed at any observed temperature, and the fiber was an infusible fiber. . In addition, the chemical resistance was also excellent, and the shape was completely retained in all of the evaluation target chemicals in the chemical solution and when taken out from the chemical solution. Further, as a result of measuring the thermogravimetric (TGA), the amount of remaining carbide is 12.6% by weight with respect to the PPSO fiber, the degree of crystallinity by wide-angle X-ray diffraction measurement is 43%, and the moisture absorption is 5.3. %Met.

Example 35
Similar to the conditions in which the fiber of Example 23 was treated with 20.0 g of poly-p-phenylene sulfide (PPS) film having a weight average molecular weight Mw of 40,000 and a crystallinity of 68% prepared in Reference Example 4. An oxidation reaction treatment was performed. The reaction was completed in 8 h, and 26.1 g of a poly-p-phenylene sulfone (PPSO) film having a weight increase of 30.3% was obtained. In the differential scanning calorimeter (DSC) measurement, the melting peak near the melting point (285 ° C.) of PPS disappeared and no melting peak was observed at any observed temperature, and this film was an infusible film. . In addition, the chemical resistance was also excellent, and the shape was completely retained in all of the evaluation target chemicals in the chemical solution and when taken out from the chemical solution. Furthermore, as a result of measuring the thermogravimetric (TGA), the amount of remaining carbide was 13.2% by weight with respect to the PPSO film, the crystallinity by wide-angle X-ray diffraction measurement was 56%, and the moisture absorption was 4.7. % And a low value.

Example 36
The oxidation reaction treatment was performed in the same manner as in Example 35 except that the poly-p-phenylene sulfide (PPS) film having a weight average molecular weight Mw of 30,000 and a crystallinity of 68% was used. The weight of the film increased by 29.2%, yielding 25.8 g of poly-p-phenylene sulfone (PPSO) film. In the differential scanning calorimeter (DSC) measurement, the melting peak near the melting point (285 ° C.) of PPS disappeared and no melting peak was observed at any observed temperature, and this film was an infusible film. . In addition, the chemical resistance was also excellent, and the shape was completely retained in all of the evaluation target chemicals in the chemical solution and when taken out from the chemical solution. Furthermore, as a result of measuring the thermogravimetric (TGA), the amount of remaining carbide was 12.9% by weight with respect to the PPSO film, the crystallinity by wide-angle X-ray diffraction measurement was 54%, and the moisture absorption was 4.6. %Met.

Example 37
An oxidation reaction treatment was carried out in the same manner as in Example 35 except that the poly-p-phenylene sulfide (PPS) film having a weight average molecular weight Mw of 40,000 and a crystallinity of 65% was prepared in Reference Example 5. The weight of the film increased by 29.5%, yielding 25.9 g of poly-p-phenylene sulfone (PPSO) film. In the differential scanning calorimeter (DSC) measurement, the melting peak near the melting point (285 ° C.) of PPS disappeared and no melting peak was observed at any observed temperature, and this film was an infusible film. . In addition, the chemical resistance was also excellent, and the shape was completely retained in all of the evaluation target chemicals in the chemical solution and when taken out from the chemical solution. Furthermore, as a result of measuring the thermogravimetric (TGA), the amount of remaining carbide is 13.1% by weight with respect to the PPSO fiber, the degree of crystallinity by wide-angle X-ray diffraction measurement is 55%, and the moisture absorption is 4.3. %Met.

Example 38
The oxidation reaction treatment was performed in the same manner as in Example 35, except that the poly-p-phenylene sulfide (PPS) film having a weight average molecular weight Mw of 30,000 and a crystallinity of 65% was prepared in Reference Example 5. The weight of the film increased by 28.3% and 25.7 g of poly-p-phenylene sulfone (PPSO) film was obtained. In the differential scanning calorimeter (DSC) measurement, the melting peak near the melting point (285 ° C.) of PPS disappeared and no melting peak was observed at any observed temperature, and this film was an infusible film. . In addition, the chemical resistance was also excellent, and the shape was completely retained in all of the evaluation target chemicals in the chemical solution and when taken out from the chemical solution. Furthermore, as a result of measuring the thermogravimetric (TGA), the amount of remaining carbide was 12.8% by weight with respect to the PPSO film, the crystallinity by wide-angle X-ray diffraction measurement was 53%, and the moisture absorption was 4.5. %Met.
The results of Examples 28-38 are shown in Table 5.

<Production of poly-p-phenylene sulfide resin>
Reference Example 7
In a 70 liter autoclave equipped with a stirrer, 8267.0 g (70.0 mol) of 47.5% sodium hydrosulfide, 2986.7 g (71.7 mol) of 96% sodium hydroxide, N-methyl-2-pyrrolidone (NMP ) 11434.5 g (115.5 mol) and 10500.0 g of ion-exchanged water were charged and gradually heated to 230 ° C. over about 3 hours while passing nitrogen at normal pressure, and 14770.0 g of water and 280.0 g of NMP were distilled. After dispensing, the reaction vessel was cooled to 160 ° C. The residual water content in the system per 1 mol of the charged alkali metal sulfide was 1.08 mol including the water consumed for the hydrolysis of NMP. The amount of hydrogen sulfide scattered was 0.015 mol per mol of the alkali metal sulfide charged.

  Next, 10368.7 g (70.5 mol) of p-dichlorobenzene (p-DCB) and 9064.4 g (91.6 mol) of NMP were added, the reaction vessel was sealed under nitrogen gas, and stirred at 240 rpm. The temperature was raised from 200 ° C. to 270 ° C. at a rate of 0.6 ° C./min, and held at 270 ° C. for 50 minutes.

  After 50 minutes at 270 ° C., it was rapidly cooled to near room temperature.

  The contents were taken out and filtered through a glass filter, and then 70 liters of warm water was poured and suction filtered. This operation was repeated several times to obtain a PPS cake. This was dried with hot air at 80 ° C. and dried under reduced pressure at 120 ° C. to obtain polyphenylene sulfide. The weight average molecular weight (Mw) of poly-p-phenylene sulfide at this time was Mw = 20,000 as a result of GPC measurement.

Reference Example 8
As a result of carrying out in the same manner as in Reference Example 7 except that the amount of p-DCB was 10338.4 g (70.3 mol), poly-p-phenylene sulfide having a weight average molecular weight Mw = 25,000 was obtained.

Preparation of poly p-phenylene sulfide resin composition (preparation of pellets before film production)
Reference Example 9
A slurry was prepared by finely dispersing 50% by weight of spherical calcite-type calcium carbonate having an average particle diameter of 1.0 μm in ethylene glycol. This slurry was filtered through a 1 μm cut filter, and then mixed with the poly-p-phenylene sulfide powder prepared in Reference Example 7 or Reference Example 8 using a Henschel mixer so that the calcium carbonate would be 5.0 wt%. Next, the mixture was supplied to a twin screw extruder having two vent holes, and ethylene glycol was removed from the vent holes simultaneously with melt kneading, extruded into a gut shape, cooled in water, and then cut into particle pellets.

  Further, only the poly-p-phenylene sulfide powder produced in Reference Example 7 or Reference Example 8 was melt-extruded in the same manner as described above to obtain particle-free pellets.

Preparation of poly-p-phenylene sulfide film Reference Example 10
The particle pellets (weight average molecular weight Mw = 20,000) and non-particle pellets (weight average molecular weight Mw = 20,000) prepared in Reference Example 9 were mixed so that the calcium carbonate would be 0.4 wt%, and the rotary type Crystallized pellets were processed in a vacuum dryer at 150 ° C. under reduced pressure of 3 mmHg (400 Pa) for 3 hours. Next, this crystallization pellet is supplied to a 90 mm diameter single screw extruder, passed through a filter having a melting temperature of 330 ° C. and a filtration accuracy of 10 μm, and discharged from a stainless steel T die having a lip width of 400 mm and a slit gap of 1.5 mm. The film was cooled and solidified on a metal drum whose surface was kept at 30 ° C. to obtain a film of poly-p-phenylene sulfide film having a thickness of 60 μm. The crystallinity of the film measured by wide-angle X-ray diffraction was 56%, and the weight average molecular weight was not different from that of the poly-p-phenylene sulfide powder prepared in Reference Example 7 or Reference Example 8.

Reference Example 11
Using only the non-particle pellets prepared in Reference Example 9 (weight average molecular weight Mw = 20,000), it was supplied to a 90 mm diameter single screw extruder in the same manner as Reference Example 10, melting temperature 330 ° C., filtration accuracy 10 μm. And is discharged from a stainless steel T-die having a lip width of 400 mm and a slit gap of 1.5 mm, cooled and solidified on a metal drum whose surface is kept at 30 ° C., and poly-p-phenylene having a thickness of 60 μm A film of sulfide film was obtained.

  The crystallinity of the film measured by wide-angle X-ray diffraction was 55%, and the weight average molecular weight was not different from that of the poly-p-phenylene sulfide powder prepared in Reference Example 7 or Reference Example 8.

Reference Example 12
The particulate pellets prepared in Reference Example 3 (weight average molecular weight Mw = 40,000) and the non-particle pellets (weight average molecular weight Mw = 40,000) were mixed so that calcium carbonate was 0.4% by weight, and rotated. Crystallized pellets were processed in a vacuum drier at 150 ° C. under reduced pressure of 3 mmHg (400 Pa) for 3 hours. Next, this crystallization pellet is supplied to a 90 mm diameter single screw extruder, passed through a filter having a melting temperature of 330 ° C. and a filtration accuracy of 10 μm, and discharged from a stainless steel T die having a lip width of 400 mm and a slit gap of 1.5 mm. The film was cooled and solidified on a metal drum whose surface was kept at 30 ° C. to obtain a film of poly-p-phenylene sulfide film having a thickness of 60 μm. The weight average molecular weight of the film was not different from that of the poly-p-phenylene sulfide powder produced in Reference Example 1 or Reference Example 2, but the degree of crystallinity by wide-angle X-ray diffraction measurement was 6%.

Reference Example 13
Using only the non-particle pellets prepared in Reference Example 3 (weight average molecular weight Mw = 40,000), it was supplied to a 90 mmφ single-screw extruder in the same manner as in Reference Example 12, and the melting temperature was 330 ° C. and the filtration accuracy was 10 μm. Passed through a filter, discharged from a stainless steel T die with a lip width of 400 mm and a slit gap of 1.5 mm, cooled and solidified on a metal drum whose surface was kept at 30 ° C., and poly-p-phenylene sulfide having a thickness of 60 μm A film film was obtained.

  The weight average molecular weight of the film was not different from that of the poly-p-phenylene sulfide powder prepared in Reference Example 1 or Reference Example 2, but the degree of crystallinity by wide-angle X-ray diffraction measurement was 5%.

<Preparation of poly-p-phenylene sulfide fiber>
Reference Example 14
Using the non-particle pellets prepared in Reference Example 9 (with a weight average molecular weight Mw = 20,000 or with a weight average molecular weight Mw = 25,000), a melting temperature of 320 ° C., a discharge rate of 350 g / min, a drawing speed An undrawn yarn having a fineness of 4375 dtex was discharged from the die at 800 m / min and dropped and cooled in an atmosphere maintained at 23 ° C. Next, the undrawn yarn was wound around a rotating roll group having a surface temperature of 98 ° C. and heated, and drawn at a draw ratio of 3.27 and a draw speed of 120 m / min. Next, it is crimped at a crimping degree of 13.0 with a crimper having a surface temperature of 90 ° C., then heat-treated by passing it through an atmosphere maintained at 125 ° C., and then cooled and cut. Thus, a poly-p-phenylene sulfide fiber having a fiber thickness (single yarn fineness) of 5.0 dtex and a length of 50 mm to 80 mm was obtained.

  The degree of crystallinity of the fibers measured by wide-angle X-ray diffraction was 25%, and the weight average molecular weight was not different from that of the poly-p-phenylene sulfide powder prepared in Reference Example 7 or Reference Example 8.

Comparative Example 4
The oxidation reaction treatment was carried out in the same manner as in Example 33 using 19.8 g of poly-p-phenylene sulfide (PPS) fibers having a weight average molecular weight Mw of 20,000 and a crystallinity of 25% prepared in Reference Example 14. . The weight of the fiber increased by 31.0% and 25.9 g of poly-p-phenylene sulfone (PPSO) fiber was obtained. This fiber was a fiber in which the melting peak near the melting point (285 ° C.) of PPS disappeared by differential scanning calorimetry (DSC), and no melting peak was observed at any observed temperature. The degree of crystallinity by diffraction measurement decreased to almost 0%. In addition, as a result of measuring thermogravimetry (TGA), the amount of remaining carbides was 13.7% by weight with respect to PPSO fiber. In addition, the moisture absorption rate of PPSO fibers obtained by oxidizing PPS fibers having a low molecular weight and low crystallinity is surprisingly 14.9%, which is extremely poor in moisture absorption resistance.

Comparative Example 5
The oxidation reaction treatment was performed in the same manner as in Comparative Example 4 except that the poly-p-phenylene sulfide (PPS) fiber having a weight average molecular weight Mw of 25,000 and a crystallinity of 25% was prepared in Reference Example 14. The weight of the fiber increased by 30.0% and 25.7 g of poly-p-phenylene sulfone (PPSO) fiber was obtained. This fiber was a fiber in which the melting peak near the melting point (285 ° C.) of PPS disappeared by differential scanning calorimetry (DSC), and no melting peak was observed at any observed temperature. The degree of crystallinity by diffraction measurement decreased to almost 0%. In addition, as a result of measuring thermogravimetry (TGA), the amount of remaining carbides was 13.5% by weight with respect to PPSO fiber. Also, the moisture absorption rate is as high as 13.0%, indicating that the moisture absorption resistance is extremely inferior.

Comparative Example 6
The oxidation reaction treatment was performed in the same manner as in Comparative Example 4 except that the poly-p-phenylene sulfide (PPS) film having a weight average molecular weight Mw of 20,000 and a crystallinity of 56% was prepared in Reference Example 10. The film weight increased by 28.7%, yielding 25.5 g of poly-p-phenylenesulfone (PPSO) film. In the differential scanning calorimeter (DSC) measurement, this film is a film in which the melting peak near the melting point of PPS (285 ° C.) disappears, and no melting peak is observed at any observed temperature, and wide-angle X-ray diffraction The crystallinity measured was reduced to almost zero. Moreover, the chemical resistance in concentrated nitric acid was slightly inferior. As a result of measuring the thermogravimetric (TGA), the amount of remaining carbide was 12.9% by weight with respect to the PPSO film. Moreover, even if the crystallinity of the PPS film is high as in this comparative example, it can be seen that when the molecular weight is low, the moisture absorption rate is as high as 9.0%.

Comparative Example 7
The oxidation reaction treatment was performed in the same manner as in Comparative Example 4 except that the poly-p-phenylene sulfide (PPS) film having a weight average molecular weight Mw of 20,000 and a crystallinity of 55% was prepared in Reference Example 11. The weight of the film increased by 29.6% and 25.7 g of poly-p-phenylene sulfone (PPSO) film was obtained. In this differential scanning calorimeter (DSC) measurement, the melting peak near the melting point of PPS (285 ° C.) disappeared and no melting peak was observed at any observed temperature. The crystallinity by diffraction measurement was reduced to almost zero. Moreover, the chemical resistance in concentrated nitric acid was slightly inferior. In addition, as a result of measuring thermogravimetry (TGA), the amount of remaining carbides was 12.6% by weight with respect to the PPSO film, and the moisture absorption was 9.0%.

Comparative Example 8
The oxidation reaction treatment was performed in the same manner as in Comparative Example 4 except that the poly-p-phenylene sulfide (PPS) film having a weight average molecular weight Mw of 40,000 and a crystallinity of 6% was prepared in Reference Example 12. The weight of the film increased by 30.5% and 25.8 g of poly-p-phenylene sulfone (PPSO) film was obtained. In this differential scanning calorimeter (DSC) measurement, the melting peak near the melting point of PPS (285 ° C.) disappeared and no melting peak was observed at any observed temperature. In the measurement of crystallinity by diffraction, virtually no crystallization peak was observed. In addition, the chemical resistance in concentrated nitric acid was slightly inferior. In addition, as a result of measuring thermogravimetry (TGA), the amount of remaining carbides was 13.0% by weight with respect to the PPSO film. It can also be seen that the moisture absorption is 15.0%, which is a PPSO film inferior in moisture absorption resistance.

Comparative Example 9
The oxidation reaction treatment was performed in the same manner as in Comparative Example 4 except that the poly-p-phenylene sulfide (PPS) film having a weight average molecular weight Mw of 40,000 and a crystallinity of 5% was prepared in Reference Example 13. The weight of the film increased by 31.3%, yielding 26.0 g of poly-p-phenylene sulfone (PPSO) film. In this differential scanning calorimeter (DSC) measurement, the melting peak near the melting point of PPS (285 ° C.) disappeared and no melting peak was observed at any observed temperature. In the measurement of crystallinity by diffraction, virtually no crystallization peak was observed. Moreover, the chemical resistance in concentrated nitric acid was slightly inferior. The obtained film was so brittle that a part of the film dropped off when it was touched. As a result of measuring thermogravimetry (TGA), the amount of remaining carbide was 13.2% by weight with respect to the PPSO film, and the moisture absorption was 14.9%.
Table 6 shows the results of Comparative Examples 4 to 9.

  The polyarylene sulfide oxide thus obtained has extremely high heat resistance and excellent chemical resistance against alkali, concentrated sulfuric acid and concentrated nitric acid. It is a useful compound and can be widely used in applications requiring heat resistance, chemical resistance, moisture absorption resistance and the like. Specifically, bug filters, chemical filters, dryer canvas, papermaking felts, sewing threads, heat-resistant felts, food filters, release materials, battery separators, heart patches, artificial blood vessels, artificial skin, printed circuit board substrates, Electrical insulation paper, chemical filter, oil filter, engine oil filter, copy rolling cleaner, air cleaning filter, safety clothing, heat resistant clothing, experimental work clothes, warm clothing, flame retardant clothing, ion exchange base material, oil retaining material, heat insulating material It can be used for separators for electrodes, protective films, heat insulating materials for construction, cushion materials, liquid absorbent cores, brushes, etc., but is not limited to these applications.

Claims (15)

The crystallinity in the measurement of wide-angle X-ray diffraction is 30 % or more, the heat of fusion in the measurement with a differential scanning calorimeter (DSC) is 15 J / g or less , and the residual carbide in the measurement of thermogravimetry (TGA) A polyarylene sulfide oxide having an amount of 1% by weight or more . Polyarylene sulfide oxide of melting peak in the measurement is substantially unrecognized claim 1 Symbol placement of a differential scanning calorimeter (DSC). It consists claim 1 polyarylene sulfide oxide according to any one of 2, a solid article having a powder, fiber, fabric, a form selected from a film and paper. A solid article composed of a polyarylene sulfide compound having a crystallinity of 50% or more in wide-angle X-ray diffraction measurement in the presence of a liquid containing 3% by weight to 10% by weight of an oxidizing agent while maintaining the form , 50 ° C. to 70 ° C. When the oxidation reaction treatment is performed at a temperature of 2 hours or more, the crystallinity in the wide-angle X-ray diffraction measurement is 30 % or more, and the heat of fusion in the measurement with a differential scanning calorimeter (DSC) is 15 J / G or less and a solid article made of a polyarylene sulfide oxide having a residual carbide content of 1% by weight or more in thermogravimetric (TGA) measurement . The manufacturing method according to claim 4 , wherein the solid article is a fiber or a fabric, and the fineness of the fiber constituting the article is 0.1 to 10 dtex. Method for producing a polyarylene sulfide compound, Weight average molecular weight (Mw) 30000 or more in a claim 4 or 5, wherein the solid article. The method for producing a solid article according to any one of claims 4 to 6 , wherein the polyarylene sulfide oxide is one in which residual carbides are substantially recognized in the measurement of thermogravimetry (TGA). The method for producing a solid article according to any one of claims 4 to 7 , wherein the oxidizing agent is at least one selected from inorganic salt peroxide and hydrogen peroxide solution. The method for producing a solid article according to any one of claims 4 to 8 , wherein the liquid contains at least one selected from an organic acid and an organic acid anhydride. The method for producing a solid article according to any one of claims 4 to 9 , wherein the liquid contains a mineral acid. The method for producing a solid article according to any one of claims 4 to 10 , wherein the liquid is a mixture containing water, acetic acid and sulfuric acid, and the oxidizing agent is hydrogen peroxide. The solid article according to claim 3 , wherein the solid article made of polyarylene sulfide oxide is used as an application selected from a filter application, a paper application, and a heat-resistant work wear application. Bag filter comprising a fabric comprising a polyarylene sulfide oxide according to any one of claims 1-2. Electrical insulating paper comprising a paper made of a polyarylene sulfide oxide according to any one of claims 1-2. Fire clothing including fabric consisting of polyarylene sulfide oxide according to any one of claims 1-2.