KR0121979B1 - Method for manufacturing flame retardant polyester - Google Patents

Abstract

The present invention relates to a method of manufacturing a flame retardant polyester by adding at least one of compound represented by the formula(I) containing phosphorous component and nitrogen component concurrently as flame retardant during polymerizing the polyester. The final polymer containing 1500-7000ppm of phosphorous and 680-3160ppm of nitrogen has predominant incombustible effect without dropping physical properties.

Description

Manufacturing method of flame retardant polyester

The present invention relates to a method for producing a polyester having excellent flame retardancy, more specifically, a compound represented by the following general formula (I) which simultaneously holds a phosphorus component and a nitrogen component as a flame retardant is added at any stage during the polymerization of the polyester Therefore, the present invention relates to a method for producing a flame retardant polyester having a small amount of flame retardant effect due to the synergistic effect of the phosphorus component and the nitrogen component, and having almost no deterioration in the physical properties of the polymer due to the addition of a small amount of flame retardant.

(Wherein R is a hydrocarbon group of 1 to 6 carbon atoms)

Polyester has excellent mechanical properties, chemical resistance, heat resistance and the like, but is used in various fields such as fibers and films, but it is a flammable material, and thus has a disadvantage of being easily ignited by combustion. In particular, in Europe and the United States, flame retardant standards have been enacted by law for infants and the elderly, curtain carpets, and the like, and thus, the necessity of flame retardancy is urgently needed for the development of polyester in the above fields.

Flame retardant methods of polyester known to date can be roughly divided into a method of adding a material that gives a flame retardant effect during polymerization and a post-steel processing method of coating a flame retardant component after spinning. The post-processing method has economic disadvantages, but has the disadvantages such as roughening the surface of the product and falling flame retardant durability by dropping the flame retardant component by washing or the like. In addition, as a flame retardant substance used in the method of adding a flame retardant substance at the time of superposition | polymerization, inorganic substance, halogen type, and phosphorus organic substance are common. As an inorganic flame retardant component, antimony trioxide is used as a representative compound. However, in the case of inorganic substances, antimony trioxide is not used because it is not compatible with organic polyester. Toxic gases are generated and regulated for use in each country, and U.S. Patent No. 3,941,752, Japanese Patent Application No. 55-41610, Korean Patent Publication No. 83-59, Japanese Patent Application No. 38-1750, Small 45- 9197, SO 52-17050, and U.S. Pat.Nos. 3,076,010 and 4,157,436 describe methods of using phosphorus-based flame retardants, but the process is complicated and the residual rate of phosphorus compounds is substantially low. There was a problem such as lowering the activity of the catalyst or lowering the melting point of the polymer, resulting in poor workability during processing and bad mechanical properties.

Accordingly, it is an object of the present invention to provide a method for producing a polyester which is excellent in flame retardant effect and does not have a decrease in physical properties of the polyester.

In order to achieve the above object as well as another object, in the present invention, flame retardance is achieved by adding and copolymerizing one or more polyester polymers represented by the above general formula (I) among the compounds containing phosphorus element and nitrogen element in the same molecule. Synthetic polyester is not only a synergistic effect in flame retardancy but also has a high reactivity due to the intrinsic high list rain, the ratio of the residual amount to the input amount is large, even if a small amount is added, there is a feature that can give a sufficient flame retardant effect.

(Wherein R is a hydrocarbon group of 1 to 6 carbon atoms)

The compound of the general formula (I) is usually obtained by reacting phenylphosphinedichloride with alkyl or arylethanolamine as base solvent and using benzene or diethyl ether as a solvent at low temperature (-10 to 0 ° C).

The flame-retardant polyester according to the present invention is made of a dicarboxylic acid component and a diol component and the compound of the general formula (I), wherein the reaction conditions, namely the shipbuilding during the transesterification reaction and the polycondensation reaction are known methods. In particular, in the case of producing polyester using a terephthalic acid or dimethyl terephthalate as the dicarboxylic acid component, and ethylene glycol as the diol component, a known alkali metal or alkaline earth metal or Perform a transesterification reaction at a temperature of 140 ° C. to 240 ° C. using a metal compound such as zinc, manganese, titanium or cobalt as a catalyst, and a pressure of normal pressure to 5 kg / cm 2 using a metal compound as a catalyst used in the transesterification reaction. And the esterification reaction is carried out under a temperature condition of 200 ° C to 280 ° C, The desired reaction product was polycondensed in the presence of a metal compound such as antimony, germanium or titanium under a temperature condition of 250 ° C. to 320 ° C. under a vacuum of 1 torr or less to prepare a desired polyester.

If the input amount of general formula (Ⅰ), the flame retardant used at this time, is less than 1500ppm for phosphorus and less than 680ppm for nitrogen, it does not have sufficient flame retardant effect. Given.

As the method used for the analysis of the polymer, the degree of polymerization was shown as the ultimate viscosity (IV), and the physical property was decreased by the content of diethylene glycol (DEG), and the coloring was compared by measuring the sulfur-blueness (b).

Intrinsic viscosity (IV) was measured at 25 ℃ using o-chlorophenol solution, DEG content was hydrolyzed polyester polymer, ethylene glycol (EG) and DEG was quantified according to gas chromatograph method The amount of DEG relative to glycol is expressed in mol%.

Phosphorus content of the synthesized polymer was measured by dissolving the polymer, followed by fluorescence X-ray method, and brightness and sulfur-blue were measured by color difference meter by crystallizing the polymer at 150 ± 2 ° C. for one hour.

On the other hand, the woven fabric has a weight of 200g per yard, and the flame retardance was measured as the average value of the number of dyeings in the 45 ° C oil method for five samples according to the method indicated in Korean Fire Law.

The following examples and comparative examples illustrate the present invention more specifically, but do not limit the scope of the present invention.

Example 1

In a stainless steel reactor with a condenser and a stirrer designed to allow a reflux installed dimethyl terephthalate and ethylene glycol, 1, and such that the molar ratio of 1.5, R = CH ₃ in formula (Ⅰ) 1500ppm compound with popular standard for the polymer After addition, the transesterification reaction usually used in the art to which the present invention pertains is carried out.

Upon completion of the transesterification reaction, a polycondensation catalyst generally used in the art to which the present invention pertains is added and the temperature is gradually increased to perform the transesterification reaction while the final temperature is raised from 220 to 230 ° C.

When the transesterification reaction is completed, the polycondensation catalyst commonly used in the technical field of the present invention is added, and the temperature is gradually raised so that the final temperature is 265 ° C. to 280 ° C., and the pressure is gradually reduced so that the final pressure is 0.1torr or less The reaction was carried out for 120 minutes to obtain a polymer having an ultimate viscosity of 0.62.

The polymer was drawn and woven in 72De./36 filament according to a conventional method to measure flame retardancy, and the results are shown in Table 1.

Example 2-Comparative Examples 1-6

Polymers, filaments and fabrics were obtained in the same manner as in Example 1 except that a flame retardant of general formula (I) having R = CH ₃ or C ₆ H ₅ was added in mol% as shown in Table 1, and the physical properties thereof were measured and The results are shown in Table 1 below.

Claims (1)

Method for producing a flame retardant polyester, characterized in that by adding at least one compound represented by the general formula (I) at the time of polyester polymerization so that the content of the final polymer element content is 1500 ~ 7000ppm, the nitrogen content is 680 ~ 3160ppm. . (Wherein R is a hydrocarbon group of 1 to 6 carbon atoms)