JPH1180340A - Production of flame-retardant polyester - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for efficiently producing the subject polyester; by which properties for transportation, storing, and handling are improved by adding a specific organophosphorus compound to the reactive component in the manufacturing process of a specific polyester and copolycondensing the added product. SOLUTION: (B) An phosphorus compound obtained by reacting (i) an organic phosphorus compound of formula I with (ii) itaconic acid and (iii) ethylene glycol by heating, and polycondensing the product by heating the reacted product and removing the component (iii) therefrom under a reduced pressure, and mainly represented by formula II [(n) is >=4 in average] is added to (A) a reactive component in the production process of a polyester preferably comprising a polyethylene terephthalate or polyethylene 2, 6-naphthalenedicarboxylate, and the added mixture is copolycondensed to provide the objective polyester in the method for producing the flame-retardant polyester. The component (i) is ordinary called 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a method for producing a flame-retardant polyester. More specifically, an organophosphorus compound represented by general formula 2, 3, or 4 (hereinafter referred to as general formula 2, general formula 3, or general formula 4) is converted into a specific polyester, ie, polyethylene. Flame-retardant polyester characterized by being added during the production process of terephthalate or polyethylene-2,6-naphthalene dicarboxylate and copolycondensed, ie, flame-retardant polyethylene terephthalate or flame-retardant polyethylene-2 , 6-naphthalene dicarboxylate. In the present invention, the specific polyester is defined as polyethylene terephthalate or polyethylene-2,6-naphthalene dicarboxylate, and the flame-retardant polyester is defined as flame-retardant polyethylene terephthalate or flame-retardant polyethylene-2,
It is defined as 6-naphthalene dicarboxylate.

[0002]

Embedded image (However, the average value of n is 4 or more.)

[0003]

Embedded image (However, the sum of the average values of n and m is 4 or more, and n
There is a relationship of 4n ≧ m between the average value of m and the average value of m. )

[0004]

Embedded image (However, the sum of the average values of n and m is 4 or more, and n
And the average value of m have a relationship of 2n ≧ m. )

[0005]

BACKGROUND OF THE INVENTION One of the polyesters referred to in the present invention is usually called polyethylene terephthalate (PET) and is widely known and used as a material for synthetic fibers or various molded articles. This synthetic fiber has good properties as a fiber such as high strength, high heat resistance, high Young's modulus, excellent dyeability, excellent texture or excellent durability, so it can be used not only for clothing, but also for bedding, interior or tires. It is also used for applications such as code. As molded products, polyethylene terephthalate is applied to applications such as photographic films, bottles, and mechanical parts by utilizing the properties of polyethylene terephthalate such as excellent transparency, excellent heat resistance, and excellent mechanical strength. With the expansion of such a wide range of applications, the production cost of polyester has been gradually reduced, and it is now becoming one of the most common and large-scale production chemical products.

Another is ethylene glycol and 2,6-
Polycondensation products with dicarboxynaphthalene (2,6-naphthalenedicarboxylic acid), generally polyethylene-
It is called 2,6-naphthalene dicarboxylate (PEN). This has been recognized as having higher strength, higher heat resistance or excellent dimensional stability, and has recently been put to practical use as a material for films and molded products. This is essentially the conversion of polyethylene terephthalate terephthalic acid to 2,6
-Polycarboxynaphthalene is replaced only by the structure, and polyester generally refers to the former, but since the present invention is effectively applied to both, the present invention uses the same for the former. Included in the polyester range.

[0007] Ordinary polyethylene terephthalate is roughly produced by the following two methods. One is an older method, now called transesterification, in which dimethyl terephthalate (referred to as DMT or dimethyl terephthalate) and excess are first placed in a reactor called transesterifier. Of ethylene glycol diester of terephthalic acid (hereinafter referred to as Structural Formula 5) which is mainly represented by Structural Formula 5, and then referred to as an autoclave. In this method, the product is transferred to a polycondensation machine, and the polycondensation reaction is allowed to proceed under heating and reduced pressure. Finally, the high-viscosity product in the autoclave is discharged at a nitrogen gas pressure to produce the product. The other is a relatively new method, in which terephthalic acid and an excess of ethylene glycol are first charged to a reactor called an esterification machine, and heated under atmospheric pressure or pressure in the presence of a catalyst. The reaction is carried out to produce Structural Formula 5, and then the product is transferred to an autoclave for producing polyester, and thereafter produced in the same manner as in the previous method.

[0008]

Embedded image In a usual method for producing polyethylene-2,6-naphthalene dicarboxylate, a diol component having a slightly flexible structure may be added as a crystallization accelerator.
Essentially, the former terephthalic acid only replaces 2,6-dicarboxynaphthalene, and is produced in much the same way as polyethylene terephthalate.

In the present invention, the "polyester production process" starts from an ester exchange machine or an esterification machine used in the production of polyester,
The entire chemical or physical process that ends in a polycondensation machine called an autoclave. In recent years, polyesters have also been produced by a continuous method, but the principle is exactly the same, so that in this case also, the whole process of polyester production starts from transesterification or esterification and ends with polycondensation.

The flame-retardant polyester was used in 1970 (197).
It has been widely studied to meet the demand for flame retardancy of synthetic fibers that started around 0), and after many changes, the present copolycondensation type flame retardant polyester has been completed.

[0011] Flame-retardant polyethylene terephthalate is disclosed in JP-A-52-47891 and JP-A-52-91.
Nos. 878, 52-97981 and 52
As described in, for example, JP-A-98089, the conventionally used flame retardants include an organic phosphorus compound represented by Structural Formula 1 (hereinafter, referred to as Structural Formula 1), itaconic acid, and fly. An ethylene glycol solution of an organic phosphorus compound represented by Structural Formula 6 (hereinafter referred to as Structural Formula 6), which is obtained by heating and reacting ethylene glycol, is generally used. A flame-retardant polyester is produced by a copolycondensation reaction. The ethylene glycol solution of the structural formula 6 is added so that the phosphorus content of the finished flame retardant polyester is 0.3 to 1.0%, and copolycondensed.

A flame retardant polyethylene-2,6-naphthalene dicarboxylate is also disclosed in JP-A-7-9743.
No. 6, as described in the publication, usually, an ethylene glycol solution of structural formula 6 is used as a flame retardant,
Manufactured in exactly the same way as the former.

The structural formula 6 as a flame retardant has the property of being easily copolycondensed with a polyester.
The flame-retardant polyester using this can be produced by adding the flame retardant in the polyester production process and by co-polycondensation without changing the conditions as in ordinary polyester. It is said that the most preferable time when these copolycondensation type flame retardants are added in the polyester production process is at the end of the reaction in an ester exchanger or an esterifier, or at the start of a reaction in an autoclave. I have.

[0014]

Embedded image

[0015]

Embedded image

[0016]

Structural formula 6 is an extremely viscous liquid which is difficult to handle if isolated. The conventional flame retardant containing this as a main component is usually produced as a solution of ethylene glycol. Transported, stored, and used. Moreover, despite the fact that this solution contains a considerable amount of ethylene glycol, it is still a highly viscous liquid, so handling it requires 5%.
It is necessary to lower the viscosity by heating to 0 ° C. or higher. In addition, the Fire Service Law designates dangerous goods as Class 4 and Class 3 petroleum, so transportation, storage and handling must follow the regulations of the Fire Service Law, which is troublesome. further,
Since the phosphorus content of this flame retardant is as low as 4 to 5%, the transportation cost per phosphorus unit cannot be neglected.

A first object of the present invention is to remove the ethylene glycol under reduced pressure by heating the ethylene glycol solution represented by the structural formula 6, and to have a high phosphorus content and a high softening point as a product of the polycondensation reaction. By using the general formula 2 as a flame retardant, while maintaining the advantage of the excellent copolycondensation with the polyester which the structural formula 6 has, the disadvantage of the conventional liquid flame retardant is its transportation. The purpose is to improve the storage, handling and handling, and to make the production of flame-retardant polyester more efficient. The same applies to general formula 3 or general formula 4.

A second object is to use a high phosphorus content solid flame retardant from which the excess ethylene glycol contained in conventional liquid flame retardants has been removed, thereby reducing the per-batch production of polyester. The purpose is to improve the productivity of flame-retardant polyester by increasing the production amount and shortening the copolycondensation time required per batch.

[0019]

According to the present invention, an organic phosphorus compound represented by the structural formula 1, itaconic acid and ethylene glycol are reacted under heating, and subsequently, polycondensation is performed while removing ethylene glycol under heating and reduced pressure. The resulting organic phosphorus compound represented by the general formula 2 is added to a process for producing a polyester selected from polyethylene terephthalate and polyethylene-2,6-naphthalene dicarboxylate and copolycondensed. A method for producing a flame-retardant polyester is provided.

According to another aspect of the present invention, structural formula 1
The organic phosphorus compound, itaconic acid and ethylene glycol represented by are reacted under heating, followed by adding terephthalic acid or dimethyl terephthalate to carry out an esterification or transesterification reaction.
An organic phosphorus compound mainly represented by the general formula 3 obtained by co-polycondensation while removing ethylene glycol under reduced pressure, is a polyester selected from polyethylene terephthalate and polyethylene-2,6-naphthalene dicarboxylate. And a process for producing a flame-retardant polyester by copolycondensation.

According to still another aspect of the present invention, the organophosphorus compound represented by the structural formula 1, itaconic acid and ethylene glycol are reacted under heating,
6-dicarboxynaphthalene or dimethyl-2,6-
An esterification or transesterification reaction is carried out by adding naphthalene dicarboxylate, and thereafter, an organic compound represented by the general formula 4 mainly obtained by copolycondensation while removing ethylene glycol under heating and reduced pressure. Provided is a method for producing a flame-retardant polyester, which comprises adding a phosphorus compound to a process for producing a polyester selected from polyethylene-terephthalate and polyethylene-2,6-naphthalene dicarboxylate and copolycondensing.

Structural formula 1 usually comprises 9,10-dihydro-9
It is called -oxa-10-phosphaphenanthrene-10-oxide and is a white solid having a melting point of 117 ° C. It is manufactured using 2-hydroxybiphenyl and phosphorus trichloride as raw materials, and has use as a raw material for a stabilizer of a polymer compound or a flame retardant. Also,
It is known that it undergoes an addition reaction with itaconic acid to produce an organic phosphorus compound represented by Structural Formula 7 (hereinafter, referred to as Structural Formula 7). Structural formula 7 is supposed to be used as a flame retardant for polyester similarly to structural formula 6, but its purification is difficult and there are some problems in production. It has not been.

[0023]

Embedded image The addition of general formula 1 with itaconic acid is an exothermic reaction,
It proceeds smoothly at 20 to 130 ° C. However, since Structural Formula 7 has its melting point around 200 ° C., and at the most preferable temperature for the reaction, Structural Formula 7 precipitates during the reaction,
The addition reaction between Structural Formula 1 and itaconic acid cannot be carried out smoothly without a solvent. Therefore, the addition reaction between Structural Formula 1 and itaconic acid is usually carried out in the presence of ethylene glycol, and Structural Formula 7 is esterified at a stroke to lead to Structural Formula 6. The ethylene glycol used here also has the purpose of reducing the viscosity of the reaction mixture,
2.5 to 3.5 times the theoretical amount of Structural Formula 6. The amount used corresponds to 5 to 7 times the theoretical amount of the flame retardant according to the present invention in the general formula 2. The ethylene glycol solution of structural formula 6 is represented by structural formula 1,
About 120 to 2 of itaconic acid and ethylene glycol
It is manufactured by reacting at 00 ° C for 5 to 10 hours. Typically, the resulting product is a 60% or less ethylene glycol solution of structural formula 6.

Thus, the phosphorus content of the conventional liquid flame retardants finished in this way is low and a higher amount of flame retardant with excess ethylene glycol, which has to be finally removed in the production of flame-retardant polyesters. I had to charge the fuel. This is usually a factor that lowers the volumetric efficiency of the autoclave, and it is necessary to remove excess ethylene glycol contained in the flame retardant, which is a factor that delays the time required for the copolycondensation reaction. Had also become.

However, the phosphorus-containing flame retardant represented by the general formula 2 obtained by subjecting the ethylene glycol solution of the structural formula 6 to a polycondensation reaction while heating and removing the ethylene glycol under reduced pressure has a relatively high softening point. It is characterized by a high phosphorus content of 8.3%, and when this flame retardant is used for the production of flame-retardant polyester, it occupies an unnecessary space in the autoclave as compared with the conventional method. The absence of this increases the production of flame retardant polyester per batch and also reduces the time required to remove excess ethylene glycol. Therefore, the productivity of the flame-retardant polyester is improved.

Terephthalic acid or dimethyl terephthalate and, if necessary, ethylene glycol are added to the ethylene glycol solution of the structural formula 6 to carry out an esterification or transesterification reaction. Thus, General Formula 3 which is one of the flame retardants according to the present invention can be produced. Naturally, as the content of the terephthalic acid of the general formula 3 increases, the phosphorus content in the flame retardant decreases. However, only a large amount of a flame retardant obtained by co-polycondensation of terephthalic acid is required, and the use of such a flame retardant does not reduce the productivity of the flame-retardant polyester. Therefore, the flame retardant represented by the general formula 3 is also added in the process of producing the polyester similarly to the flame retardant represented by the general formula 2, and can be used for the purpose of producing a flame-retardant polyester more efficiently.

In addition, 2,6-dicarboxynaphthalene or dimethyl-
2,6-naphthalene dicarboxylate and, if necessary, ethylene glycol and copolycondensation in the same manner as the former, yielding a flame retardant represented by the general formula 4.
And general formula 4 also has the same purpose as general formula 3,
It can be used for the production of flame retardant polyester.

In general, general formula 3 represents flame-retardant polyethylene terephthalate, and general formula 4 represents flame-retardant polyethylene-terephthalate.
Most preferably, they are used for 2,6-naphthalene dicarboxylate, respectively, but in the present invention, no limitation is required.

Each of the general formulas 2, 3 and 4 is a glassy solid having a high softening point and does not fall under the category of dangerous goods under the Fire Service Law. It is both safe and convenient.

When the ethylene glycol solution of the structural formula 6 is subjected to a polycondensation reaction by removing the ethylene glycol under reduced pressure while heating the ethylene glycol solution to produce the general formula 2, if a catalyst is present, the reaction is accelerated. At the same time as saving time,
The molecular weight of the general formula 2 can be increased. The same can be said for manufacturing the general formula 3 or the general formula 4.

In general, as a catalyst for the polyester polycondensation reaction, a mixture of two or more metal catalysts such as antimony trioxide, germanium oxide, calcium acetate, cobalt acetate, manganese acetate or zinc acetate may be used. Many. Fortunately, general formulas 2, 3, and 4
In the production of polyester, all the catalysts used in the production of the polyester are effective. Therefore, if the same type of catalyst is used, there is little concern that harmful effects will occur in the production of the flame-retardant polyester.

If the ethylene glycol solution of the structural formula 6 is heated to reduce the pressure inside the reactor, ethylene glycol boils and is removed from the system. With the removal of ethylene glycol, the stoichiometric equilibrium is lost, and as a corrective action, structural formula 6 self-condenses to produce more ethylene glycol. If the generated ethylene glycol is also removed, the polycondensation reaction proceeds to increase the molecular weight, thereby producing a flame retardant represented by the general formula 2. The final reaction conditions at this time are a temperature of 200 to 250 ° C. and a degree of vacuum of 0.
01 to 3 Torr and the reaction time is 3 to 20 hours.

Here, if a catalyst is present, the time required for the polycondensation reaction is shortened, and general formula 2 having a larger molecular weight is obtained. As a catalyst actually used, Sb ₂ O ₃ −
(AcO) ₂ Ca-based, Sb ₂ O ₃ — (AcO) ₂ Mn
_{System, Sb 2 O 3 - (AcO} ) 2 Co -based, Sb ₂ O ₃ -
(AcO) ₂ Zn-based, GeO _2- (AcO) ₂ Ca-based,
GeO _2- (AcO) ₂ Mn, GeO _2- (AcO)
₂ Co-based or GeO ₂ - (AcO) ₂ is Zn-based and the like, this addition to, any of the catalysts used during polycondensation of polyester may be used.

Also, for example, dimethyl terephthalate and Sb ₂ O ₃
-(AcO) ₂ Zn-based catalyst and, if necessary, ethylene glycol are added to bring the mixture to about 200 ° C.,
The transesterification reaction between dimethyl terephthalate and ethylene glycol proceeds to produce methanol. Methanol is distilled out of the reactor simultaneously with the production. When the production of methanol is completed, the copolycondensation reaction proceeds while reducing the pressure inside the reactor to remove ethylene glycol. The final reaction conditions are the same as in the general formula 2, and a phosphorus-containing flame retardant having a high softening point represented by the general formula 3 is produced.

Further, it is also possible to produce the general formula 3 by reacting the structural formula 1, ethylene glycol itaconate and terephthalic acid or dimethyl terephthalate at once, and this is also included in the scope of the present invention. The production of the general formula 4 is carried out similarly to the former, except that the dimethyl terephthalate used in the production of the general formula 3 is replaced with dimethyl-2,6-naphthalene dicarboxylate.

The sum of the average value of n in the general formula 2 and the average value of n and m in the general formula 3 or 4 is 4 or more. If the average value or the sum of the average values is less than 4, the softening point of the flame retardant represented by the general formula 2, general formula 3, or general formula 4 will not be sufficiently high, and blocking will occur during transportation or storage. It is not preferable because it is agglomerated and changes into a state that is difficult to handle. The sum of the average value of n in the general formula 2 and the average value of n and m in the general formula 3 or 4 is more preferably 6 or more, and further preferably 10 or more. There is no need to set an upper limit on the average value of n in the general formula 2 and the sum of the average values of n and m in the general formula 3 or 4, and the product having the highest numerical value obtained by a normal synthesis method is used. Even so, it can be used without any hindrance for the purpose of the present invention. Incidentally, the maximum of the average value of n in the general formula 2 obtained by the ordinary synthesis method is about 40, and the general formula 3
Alternatively, the maximum of the sum of the average values of n and m in the general formula 4 is about 90.
Met.

In addition, between n and m in the general formula 3, 4n ≧
m, and 2n ≧ m between n and m in the general formula 4.
There is a relationship. These relationships are limitations provided by the fact that if the phosphorus content of the flame retardant is too low, the efficiency of the production of the flame retardant polyester intended for the present invention is impaired, and the purpose of the efficiency improvement is somewhat reduced. However, if it can be sacrificed, the flame-retardant polyester can be produced smoothly as in the present invention, even outside this limit.

Conventionally, flame-retardant polyethylene terephthalate is prepared by mixing ethylene glycol solutions of structural formulas 5 and 6 and copolycondensing while heating and removing the ethylene glycol under reduced pressure in an autoclave. Being manufactured. The catalyst for the polycondensation reaction is represented by the following structural formula 5
Is generally added at the time of preparing the compound, and the catalyst is rarely added again at the time of copolycondensation. The copolycondensation reaction is carried out at a temperature of 260 to 295 ° C. and a degree of vacuum of 0.01 to 3 Torr, and the end point of the reaction is determined while observing an increase in the stirring torque of the reactor. Generally, the amount of the flame retardant used is adjusted so that the phosphorus content in the flame-retardant polyethylene terephthalate is 0.3 to 1.0% depending on the required degree of flame retardancy.

However, even when the general formula 2, 3 or 4 of the present invention is used as a flame retardant, a flame-retardant polyester can be produced in exactly the same manner as in the conventional method. That is, structural formula 5 or di (hydroxyethyl)
The required amount of general formula 2, general formula 3 or general formula 4 is added to -2,6-naphthalene dicarboxylate and copolycondensed in the same manner as in a normal polyester production method to produce a flame-retardant polyester. Is done. As long as the finished flame-retardant polyester has a constant phosphorus content, any of the conventional methods using the structural formula 6 as a flame retardant and the method of the present invention using the general formula 2, general formula 3 or general formula 4 can be used for any analysis. Even if we make full use of the means, we cannot distinguish them at all. It is understood that this is because the general formula 2, general formula 3 or general formula 4 is rearranged in the polyester by depolymerization or transesterification during the production of the polyester.

As the phosphorus-containing flame retardant of the copolymerization type of the polyester, an organic phosphorus compound represented by the structural formula 8 or 9 is known in addition to the structural formula 6.

[0041]

Embedded image

[0042]

Embedded image (However, φ represents a phenyl group.) If these organophosphorus compounds do not impair the excellent copolymerizability with the polyester represented by the general formula 2, 3, or 4 as long as they do not impair the excellent copolymerizability. The flame-retardant polyester of the present invention can be produced without any trouble when used in combination with the flame retardant of the present invention.

Further, the flame retardant according to the present invention is also used for those which are usually obtained by co-polycondensation of other ester-forming organic compounds and which are usually referred to as modified polyesters. It is possible to produce conductive polyester.

[0044]

EXAMPLES In order to further clarify the present invention, the production examples of the flame retardant according to the present invention, examples of the present invention and comparative examples will be described. In addition,% in an example shall express a weight% unless there is particular notice. Production Example 1 9,10-dihydro-9-oxa-10- was placed in a 3,000 ml hard glass four-necked flask equipped with a stirrer, a thermometer, a gas inlet, and a distillation port.
1,297 g (6 mol) of phosphaphenanthrene-10-oxide (Structural Formula 1) and 1,241 g (6 × 3.33 mol) of ethylene glycol were charged, and the flask was heated. When the temperature of the contents reached 100 ° C., 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide was dissolved in ethylene glycol.
Grams (6 x 1.02 mol) were added. Connect to the pressure reducer through the distillation port of the flask.
The vacuum was maintained at r, and the flask was continuously heated. The contents began to boil at about 115 ° C., so the distillation rate at the distillation port was adjusted to remove only the water produced by the reaction. Subsequently, the degree of vacuum in the flask was gradually reduced, and at the same time, the temperature was increased by heating so that the contents were constantly in a boiling state. While only water generated during this time was immediately removed, the degree of pressure reduction was adjusted so that the temperature of the contents reached a final temperature of 200 ° C. It took 4 hours for the temperature of the contents to reach 185 ° C., and the final degree of vacuum was 430 Torr. Then, the temperature rises with the progress of the reaction,
200 ° C. was reached. Approximately 6 hours after the temperature of the contents reached 185 ° C., no water was produced and distilled off by the reaction. This was regarded as the end point of the reaction, and nitrogen gas was blown into the reactor to return the flask to normal pressure. The reaction mixture is an ethylene glycol solution of structural formula 6,
When cooled, it was a very viscous liquid.

In addition, antimony trioxide (Sb ₂ O ₃ )
0.25 grams and zinc acetate @ (AcO) ₂ Zn.2
Ethylene glycol 10 containing 0.22 grams of H ₂ O
0 grams, while keeping the inside of the flask at 200 ° C,
The degree of vacuum in the flask was gradually increased, and the pressure was reduced to 1 Torr or less while adjusting so that ethylene glycol was distilled out smoothly. Here, the temperature was raised to 220 ° C., and ethylene glycol was continuously distilled off. After about 5 hours, the distillation of ethylene glycol was extremely reduced and was regarded as the end point of the reaction. While slightly pressurizing the contents of the flask with nitrogen gas, the contents were poured into a stainless steel vat and solidified. This was a general formula 2 and was a pale yellow transparent glassy solid. The softening point is 92 ° C. and gel permeation chromatography (G
The average molecular weight measured by PC) was 6,800 and the phosphorus content was 8.31%. Therefore, the average value of n in the general formula 2 was equivalent to 18.1.

In the measurement of the molecular weight by GPC, this product contained a small amount of a part deviating from the normal distribution in the low molecular weight region. It is speculated that it may be the presence of an acid anhydride of the formula 7 or a cyclic ester of the formula 7 with ethylene glycol. Therefore, originally, it is more appropriate that the product is expressed as “mainly an organic phosphorus compound represented by the general formula 2”. Production Example 2 9,10-Dihydro-9-oxa-10- was placed in the same 3,000 ml four-necked flask as in Production Example 1.
Phosphaphenanthrene-10-oxide 864.
A flask was charged with 7 grams (4 moles) and 826.7 grams (4 × 3.33 moles) of ethylene glycol. When the temperature reached 100 ° C. and the contents were dissolved, the mixture was stirred and 530.7 g of itaconic acid (4 × 1.
02 mol), and structural formula 6
Of ethylene glycol was prepared.

Next, dimethyl terephthalate 7
76 grams and 100 grams of an ethylene glycol solution containing 0.25 grams of antimony trioxide and 0.22 grams of zinc acetate were added. The temperature of the content was raised to 130 ° C. by heating the flask, and the content was dissolved. The mixture was further heated while stirring. The temperature of the contents is 1
The heating and decompression of the flask were adjusted so that the methanol produced by the reaction at 50 to 200 ° C. was removed smoothly. After the production of methanol was completed, the degree of vacuum in the flask was gradually increased at 200 ° C. so that ethylene glycol was removed. Finally, the inside of the flask was evacuated to 1 Torr or less, and the temperature was gradually increased while watching the boiling state in the flask to reach 220 ° C., and the copolycondensation reaction was continued at that temperature for 5 hours. Then, almost no ethylene glycol was distilled off, so the reaction was regarded as completed. The contents were discharged into a stainless steel vat at a low nitrogen pressure, cooled and solidified. The product was of general formula 3 and was a slightly yellowish glassy solid. Its softening point is 88 ° C and the average molecular weight is 9,80.
0 and the phosphorus content was 5.48%. Therefore, the sum of the average values of n and m in the general formula 3 corresponds to 34.8, and n =
m. Production Example 3 9,10-dihydro-9-oxa-10- was placed in the same 3,000 ml four-necked flask as in Production Example 1.
Phosphaphenanthrene-10-oxide 605.
3 grams (2.8 moles) and ethylene glycol 86
Eight grams (2.8 x 5 moles) were charged and the flask was heated. When the temperature of the contents reached 100 ° C., the contents were dissolved, and 368.7 g of itaconic acid (2.8 × 1.012 mol) was added with stirring. An ethylene glycol solution of Structural Formula 6 was obtained in the same manner as in the production method of Structural Formula 6 of Production Example 1.

Here, dimethyl terephthalate 1,63
1.2 grams (2.8 x 3 moles) and 300 grams of an ethylene glycol solution containing 0.35 grams of antimony trioxide and 0.61 grams of zinc acetate were added. The transesterification reaction was completed by adjusting the heating and the degree of vacuum so that methanol was distilled off smoothly when the contents of the flask were heated to 150 to 200 ° C. Subsequently, while gradually increasing the degree of vacuum in the flask while maintaining this temperature,
Ethylene glycol was removed to allow the copolycondensation reaction to proceed. By the end of the reaction, under a vacuum of 1 Torr or less,
The reaction temperature was 220 ° C. and required 5 hours. The product has the general formula 3, a softening point of 83.5 ° C. and a phosphorus content of 3.
25% and the average molecular weight was 10,500. Therefore, the sum of the average values of n and m in the general formula 3 was 44.3, and 3n = m. Production Example 4 9,10-Dihydro-9-oxa-10- was placed in the same 3,000 ml four-necked flask as in Production Example 1.
Phosphaphenanthrene-10-oxide 562.
1 gram (2.6 mol) and ethylene glycol 87
0.0 grams (2.6 x 5.4 moles) were charged and the flask was heated. At about 90 ° C., the contents of the flask had dissolved, and while stirring, 342.4 grams (2.6 × 1.012 moles) of itaconic acid were added. In the same manner as in Production Example 1, an ethylene glycol solution represented by Structural Formula 6 was obtained.

Here, dimethyl terephthalate 201
9.6 g (2.6 × 4 mol) and 300 g of an ethylene glycol solution containing 0.35 g of antimony trioxide and 0.61 g of zinc acetate were added, and thereafter, as in Production Example 3, General formula 3 was obtained. The softening point of the product was 83 ° C., the phosphorus content was 2.72% and the average molecular weight was 11,300. Therefore, n of the general formula 3
And the average value of m was 49.6, and 4n = m. Production Example 5 Using the same four-necked flask with a 3,000 ml internal volume as in Production Example 1, 864.7 g of 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide ( 4 mol), ethylene glycol 82
6.7 grams (4 x 3.33 moles) and itaconic acid 5
From 30.7 g (4 × 1.02 mol), an ethylene glycol solution of structural formula 6 was obtained in exactly the same manner as in Production Example 2.

To this was added 100 g of an ethylene glycol solution containing 977 g (4 mol) of dimethyl-2,6-naphthalene dicarboxylate, 0.5 g of antimony trioxide and 0.87 g of zinc acetate. An organophosphorus compound corresponding to the general formula 4 was obtained in the same manner as in Production Example 2. It was a yellowish glassy solid having a softening point of 96 ° C., a phosphorus content of 5.02% and an average molecular weight of 10.500. Therefore, n and m
Was equivalent to 34.0, and n = m. Example 1 In a 3,000 ml hard glass four-necked flask equipped with a stirrer, a thermometer, a gas inlet and a rectification column, 1,552 g of dimethyl terephthalate, (8 mol), ethylene glycol 1 , 141 grams (8 x 2.3 moles), 0.12 grams of antimony trioxide and 0.35 grams of zinc acetate were charged to the flask. The contents were dissolved at 130 ° C., so the flask was further heated while stirring. Since methanol was distilled off from the top of the rectification column by the reaction, only methanol was removed. The temperature of the contents increased with the progress of the reaction, and the distillation of methanol was stopped at about 230 ° C., so the reaction was considered to be completed. This is structural formula 5
Is an ethylene glycol solution.

The total amount and 130 g of the product of Production Example 1 of the general formula 2 were charged into an autoclave having an internal volume of 3,000 ml for polyester polymerization. The temperature of the contents was increased by heating the autoclave, and the pressure in the autoclave was gradually reduced so that ethylene glycol was smoothly removed. As the final reaction conditions, the reaction was completed at a pressure of 0.1 Torr, a temperature of 270 ° C. and a time of 45 minutes. The flame retardant polyester obtained has an intrinsic viscosity of 0.61 and a phosphorus content of 0.6.
4%. Example 2 An ethylene glycol solution of structural formula 5 obtained in exactly the same manner as in Example 1 was added to n =
Then, 200 g of the product m was added, and a flame-retardant polyester was obtained in the same manner as in Example 1. It had an intrinsic viscosity of 0.61 and a phosphorus content of 0.62%. Example 3 3n of the general formula 3 obtained in Production Example 3 was added to the ethylene glycol solution of the structural formula 5 obtained in exactly the same manner as in Example 1.
= M was added, and a flame-retardant polyester was obtained in the same manner as in Example 1. It had an intrinsic viscosity of 0.62 and a phosphorus content of 0.62%. Example 4 4n of the general formula 3 obtained in Production Example 4 was added to the ethylene glycol solution of the structural formula 5 obtained in the same manner as in Example 1.
= M was added, and a flame-retardant polyester was obtained in the same manner as in Example 1. It had an intrinsic viscosity of 0.60 and a phosphorus content of 0.62%. Example 5 1,586 g (6.5 g) of dimethyl-2,6-naphthalene dicarboxylate, 967 g of ethylene glycol and 0.35 g of dimethyl-2,6-naphthalene dicarboxylate were placed in a 3,000 ml four-necked flask in the same manner as in Production Example 1. And 0.38 grams of antimony trioxide were charged and the flask was heated. When the temperature reached 160 ° C and the contents dissolved,
I started mixing. Immediately, methanol is distilled off.
, Distillation of methanol was completed and the reaction was completed. The product is mainly di (hydroxyethyl) -2,6-naphthalene dicarboxylate.

The total amount of the above product, 130 g of the general formula 2 obtained in Production Example 1, and tetraethylene glycol 45
G (0.232 mol) and trimethyl phosphate (0.33 g) were charged into a 3,000 ml polyester autoclave for polyester production, and the autoclave was heated to gradually raise the temperature of the contents and to increase the internal pressure of the autoclave. To remove ethylene glycol. The final condition of the reaction is that the temperature is 2
85 ° C., pressure 0.1 Torr and time 40 minutes. The intrinsic viscosity of the obtained flame retardant polyester is 0.4
0 and the phosphorus content was 0.62%. Example 6 A product mainly comprising di (hydroxyethyl) -2,6-naphthalene dicarboxylate was obtained in exactly the same manner as in Example 5.

The total amount of this product, 225 g of the general formula 4 (n = m) obtained in Production Example 5, 45 g of tetraethylene glycol and 0.1 g of trimethyl phosphate.
33 grams were charged to the autoclave and again in Example 5
In the same manner as in the above, a flame-retardant polyester was obtained. The intrinsic viscosity was 0.39 and the phosphorus content was 0.61%. Comparative Example 1 Instead of 130 grams of the general formula 2 used in Example 1, an ethylene glycol solution of the structural formula 6 (phosphorus content:
(4.5%) was used in the same manner as in Example 1 except that 240 g of a flame-retardant polyester was used. The reaction end time required 65 minutes. Its intrinsic viscosity was 0.61 and the phosphorus content was 0.63%. Comparative Example 2 Instead of 130 grams of the general formula 2 used in Example 5, an ethylene glycol solution of the structural formula 6 (phosphorus content:
(4.5%) was used in almost the same manner as in Example 5 except that 240 g of a flame-retardant polyester was used. The reaction end time required 60 minutes. Its intrinsic viscosity was 0.40 and the phosphorus content was 0.62%. Example 7 Examples 1 to 6 and Comparative Examples 1 and 2
The yarn obtained by spinning and drawing the flame-retardant polyester, ordinary phosphorus-free ordinary polyethylene terephthalate (PET) and ordinary polyethylene-2,6-naphthalene dicarboxylate (PEN) obtained by the above method is used. The knit was made into a knit, and 1 gram thereof was put into a 10 cm long wire coil. This was held at a 45 degree angle and fired from the bottom. When the flame was removed and the sample was digested, ignition was repeated again and the number of ignitions required to burn the entire sample was measured. The same measurement was performed five times for one sample to evaluate the flame retardancy.
Table 1 shows the results.

[0054]

[Table 1]

[0055]

From the results of the evaluation of the flame retardancy of Example 7, both the flame retardant polyesters according to the present invention of Examples 1 to 6 and the flame retardant polyesters according to the conventional methods of Comparative Examples 1 and 2 were obtained. Performance was equivalent as a flame retardant polymer.

As an effect of the production method, general formulas (2), (3) and (4), which are glassy solids having a high phosphorus content and a high softening point for the production of flame-retardant polyesters,
By using as a flame retardant component, its transport, storage and handling properties are improved.Furthermore, in the production of flame-retardant polyesters, the production per batch and the polycondensation time required per batch are shortened, and The productivity of the conductive polyester can be improved.

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Hiroshi Sumitomo 657-1, Shimonosato-cho, Moriyama-shi, Shiga Pref.

Claims (9)

[Claims] An organic phosphorus compound represented by Structural Formula 1, itaconic acid and ethylene glycol are reacted under heating, and subsequently subjected to polycondensation while removing ethylene glycol under heating and reduced pressure. Mainly formula 2
A method for producing a flame-retardant polyester, characterized by adding an organophosphorus compound represented by the formula (1) to a reaction component in a production process of a specific polyester and copolycondensation. Embedded image Embedded image (However, the average value of n is 4 or more.) 2. An organic phosphorus compound represented by Structural Formula 1, itaconic acid and ethylene glycol are reacted under heating, followed by addition of terephthalic acid or dimethyl terephthalate to carry out esterification or transesterification. Then, while removing ethylene glycol under heating and reduced pressure, an organophosphorus compound mainly obtained by copolycondensation and represented by the general formula 3 is added to a reaction component in a specific polyester production process, A method for producing a flame-retardant polyester, comprising copolycondensation. Embedded image (However, the sum of the average values of n and m is 4 or more, and n
There is a relationship of 4n ≧ m between the average value of m and the average value of m. ) 3. The organic phosphorus compound represented by the structural formula 1, itaconic acid and ethylene glycol are reacted under heating, and subsequently, 2,6-dicarboxynaphthalene or dimethyl-2,6-naphthalene dicarboxylate is converted. In addition, an esterification or transesterification reaction is performed,
Thereafter, an organic phosphorus compound mainly represented by the general formula 4 obtained by copolycondensation while removing ethylene glycol under heating and reduced pressure is added to a reaction component in a production process of a specific polyester. And a method for producing a flame-retardant polyester, which comprises copolycondensation. Embedded image (However, the sum of the average values of n and m is 4 or more, and n
And the average value of m have a relationship of 2n ≧ m. ) 4. The method for producing a flame-retardant polyester according to claim 1, wherein the specific polyester is polyethylene terephthalate or polyethylene-2,6-naphthalene dicarboxylate. 5. The organophosphorus compound represented by the general formula 3 by reacting the organophosphorus compound of the structural formula 1, itaconic acid, ethylene glycol and terephthalic acid or dimethyl terephthalate at once.
A method for producing the flame-retardant polyester according to the above. 6. The organic phosphorus compound of the structural formula 1, itaconic acid, ethylene glycol and 2,6-dicarboxynaphthalene or dimethyl-2,6-naphthalene dicarboxylate are reacted at once, and the compound of the general formula The method for producing a flame-retardant polyester according to claim 3, wherein the organophosphorus compound represented by (4) is produced. 7. The process for producing the specific polyester to which the organophosphorus compound of the general formula 2 is to be added is at the end of the reaction in an ester exchanger or an esterifier for producing polyester, or a polycondensation reaction in an autoclave. The method for producing a flame-retardant polyester according to claim 1, which is at the start. 8. The process for producing the specific polyester to which the organophosphorus compound of the general formula 3 is to be added is at the end of the reaction in an ester exchanger or an esterifier for producing polyester, or a polycondensation reaction in an autoclave. The method for producing a flame-retardant polyester according to claim 2, which is at the start. 9. The process for producing the specific polyester to which the organophosphorus compound of the general formula 4 is to be added is at the end of the reaction in an ester exchanger or an esterifier for producing polyester, or a polycondensation reaction in an autoclave. The method for producing a flame-retardant polyester according to claim 3, which is at the start.