KR940003873B1 - Forming method of noninflammable polyester ester block copolymers - Google Patents

Abstract

This new flame retardant polyetherester keeps the essential characters as elastomer and at the same time it has good flame retardant and thermal stability. This one comprises: halogenated polyol 5-20 wt.parts, polypentabromobenzyl acrylate 5-20 wt.parts, antimony trioxide 2-10 wt.parts and silica 1-10 wt.parts in the basis of polyetherester block copolymer 100 wt.parts. The above halogenated polyol gives flame retardant to the chain itself so copolymer doesn't lose its rubber-like properties and mechanical properties.

Description

Method for producing flame retardant polyether ester block copolymer

The present invention relates to a method for producing a flame retardant polyether ester block copolymer, and more particularly, by containing polypentabromobanyl acrylate and antimony trioxide, it is excellent in flame retardancy while maintaining the original properties of the elastic body as it is, The present invention relates to a method for producing a flame-retardant polyether ester block copolymer that is thermally stable and does not generate blooming even when used for a long time in high temperature and high humidity conditions.

In general, the polyether ester block copolymer may be represented by the following structural formula (I), which is an irregular copolymer of the polyester portion of the structural formula (I-1) and the polyether portion of the structural formula (I-2) in the form of a block. Wherein the polyester portion exhibits crystalline properties and the polyether portion exhibits rubbery properties.

Wherein D is an aliphatic or cyclic glycol single or mixed component having 3 to 8 carbon atoms, such as ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1., 4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,4-cyclohexanedimethanol, and the like, and R is an aromatic, aliphatic or cyclic dicarboxylic acid alone or as a mixed component, for example terephthalic acid and isophthalic acid. , Old phthalic acid, adipic acid, suberic acid, azeraic acid, sebacic acid, 1,4-cyclohexanedicarboxylic acid, or a low alkyl ester product thereof, G is a poly (alkylene oxide) having a molecular weight of about 400 to 4000 As a component of the glycol alone or a mixture, for example, polyethylene glycol, polypropylene glycol, polytetramethylene glycol, and the like can be used.

In addition, the hard segment, such as the structural formula (I-1) may be included in the polyether ester copolymer up to 15 to 95% by weight, the lower the content of the hard segment shows a physical property closer to rubber than plastic. In addition, the physical properties of the final polymer largely depends on the poly (alkylene oxide) glycol component. Polyethylene glycol has a relatively high hydrophilicity compared to polypropylene glycol and polytetramethylene glycol. Since polypropylene glycol and polytetramethylene glycol are hydrophobic, they are excellent in water resistance and hydrolysis resistance. In addition, the polyether ester copolymer is a soft segment of which the polyether component has a long amorphous chain length and exhibits elasticity, and when the polyester component receives heat as a hard segment having a short crystalline chain length, the crystallinity is broken. When the heat is removed, it is a component having excellent thermoplasticity which shows crystallinity again. These soft and hard segments have an intermediate property between rubber and plastic as their ratio is controlled.

Such polyetherester block copolymers can be prepared by conventional transesterification and condensation reactions, the details of which are described in US Pat. Nos. 3,023,192, 3,651,014, 3,763,109 and 3,766,146. Polyetherester block copolymers are widely used in hoses, belts, tires, and wire coatings because of their excellent flexibility and elastic recovery ability, but they are limited in the electrical and electronic fields and wire coating fields, where flame retardancy is essential due to their flammability. Has been. Therefore, in order to solve these disadvantages, there is a method of using a halogenated diphenyl oxide as a flame retardant as a conventional flame retardant, as in the conventional resin flame retardant method, in this method is excellent in flame retardancy, but the flame retardant is deposited or in use during processing or molding Blooming phenomenon is generated, there is a severe disadvantage that the mechanical properties are deteriorated accordingly. In addition, European Patent No. 0149190 proposes a method of flame retardant using N, N'-ethylenebis (tetrabromophthalimide), and in Korean Patent Application No. 87-3600, polypentabromobenzyl acrylate and The method of imparting flame retardancy using antimony trioxide has been proposed. However, since these methods have a very high flame retardant content, the rubber properties and mechanical strength such as flexibility, elastic recovery and impact resistance of the polyether ester block copolymer are severely degraded. There was a downside.

Accordingly, the present invention adds polypentabromobenzyl acrylate, antimony trioxide, and the like as a flame retardant to solve the conventional problems as described above, thereby maximizing the rubber properties of the polyether ester block copolymer and at the same time excellent in flame retardancy. It is an object to provide a method for producing a polyether ester block copolymer.

Hereinafter, the present invention will be described in detail.

In the present invention, in preparing a flame-retardant polyether ester block copolymer, 5 to 20 parts by weight of a halogenated polyol, 5 to 20 parts by weight of polypentabromobenzyl acrylate, and antimony trioxide 2 with respect to 100 parts by weight of a polyether ester block copolymer It is a method for producing a flame-retardant polyether ester block copolymer, characterized in that by adding to 10 to 10 parts by weight and 1 to 10 parts by weight of silica.

The present invention will be described in more detail as follows.

The present invention provides a flame retardant polyether ester block copolymer, 5 to 20 parts by weight of a halogenated polyol, 5 to 20 parts by weight of polypentabromobenzyl acrylate, and antimony trioxide, based on 100 parts by weight of a polyether ester block copolymer. Flame retardancy is obtained by copolymerizing a halogenated polyol, which is a rubber component which can impart flame retardancy to a molecular chain itself, by producing a flame retardant polyether ester block copolymer by adding 10 to 10 parts by weight and 1 to 10 parts by weight of silica. will be. In other words, conventionally, since a flame retardant is introduced from the outside, a large amount of flame retardant is required, and thus there is a possibility that the rubber and mechanical properties of the polyether ester block copolymer may be impaired. The flame retardant component that can be copolymerized includes glycols, carboxylic acids, hydroxycarboxylic acids, and polyols containing phosphorus or halogenated components. In order to maintain the properties of the polyether ester block copolymer, Preference is given to using the polyol component. In addition, the polyol containing phosphorus component is prepared by reacting phosphoric acid, phosphorous acid or organic phosphoric acid with alkylene oxide, and the flame retardant effect has a method of stopping combustion by promoting carbonization and forming a protective film during combustion, but it is weak to hydrolysis. Because of this, it can cause many problems in actual use. In contrast, the halogenated polyol component is a form in which a halogen element is substituted in the structure, thereby suppressing radical reaction during combustion and suppressing the generation of flammable gas, thereby exhibiting a flame retardant effect. Ixol [IXOL] M-125 from Solvay [SOLVAY], a 45% epichlorohydrin halogenated polyol, or a termoline [THERMOLIN] RF-230 from Asahigarasu, a trichlorobutylene oxide polymer containing 60% chlorine The halogenated polyol component may be used to inhibit the radical reaction of combustion and to be substituted with halogen element of at least 5%.

In order to introduce such a flame-retardant polyol into the polyether ester block copolymer structure, it may be added during the polyether ester block copolymer polymerization reaction, but at this time, the polymerization reaction rate is lowered due to a large amount of halogen components. There exists a possibility of reducing the physical property of a copolymer base resin. Therefore, even if the halogenated polyol is introduced in the heat-melting mixing step after the reaction, it can be introduced into the molecular structure due to the esterification reaction with the carboxyl terminus of the polyether ester block copolymer. Due to the high molecular weight, no precipitation occurs.

The method for producing a flame-retardant polyether ester block copolymer of the present invention is as follows, i.e., a component, a catalyst, and various stabilizers constituting the polyether ester block copolymer are added to a conventional polyester reaction tube, and reacted at normal pressure. The ester reaction is carried out while raising the temperature of the tube to 200 to 230 ° C. over 2 hours while removing the low molecular condensation by-products such as methanol and water. When the low-molecular condensate is completely removed, the pressure of the reaction tube is gradually reduced to 1 mmHg or less over 0.5 to 1.5 hours, while the temperature of the reaction tube is gradually raised to 250 to 280 ° C. while the excess glycol component is removed to increase the degree of polymerization. When the reaction is stopped at a suitable stirring load, nitrogen is injected to reduce the pressure in the reaction tube to atmospheric pressure, and the polymer is discharged, a polyether ester block copolymer can be obtained. The reaction catalyst used here is tetraalkyl titanate alone or a mixture of magnesium or calcium acetate, and Mg [HTi (OR) ₆ ] ₂ (R is methyl, ethyl, propyl, produced from an alkoxide compound of an alkaline earth metal and an ester compound of titanate). Complex compounds of titanates, such as isopropyl, butyl, bis-2-ethylhexyl, and the like, inorganic titanate compounds such as titanium titanate, mixtures of calcium acetate and antimony trioxide, lithium or magnesium acetate, organotin Compounds or mixtures of organotin compounds and organotitanium compounds also exhibit excellent catalytic performance.

In addition, in order to further improve the heat or light stability of the polyether ester block copolymer, a part of the polyalkylene oxide glycol may be replaced with a dimer acid. The dimer acid which may be used in the present invention may be oleic acid or linoleic acid. It is prepared by dimerization of 18 linear aliphatic acids containing 18 unsaturated carbon atoms, including unsaturated double bonds such as linolenic acid and the like. This method is described in US Pat. No. 2,347,562, which is commercially available. EMERY Corporation's EMPOL 1010 and 1014, HENKEL and UNIICHEMICAL. In addition, the dimer acid produced by dimerization of linear aliphatic acid contains not only dimers but also monomers and trimers, and the content of monomers and trimers is preferably 5% by weight or less. In the present invention, in order to improve the melt strength of the final polymer, a polyfunctional component and an acrylic compound composed of a carboxyl group, a hydroxyl group, a primary or secondary amine group, an isocyanate group, a glycidyl ether group, and the like are added to the thistle. It is also possible to induce a small amount of chemical bonds, trimer in the dimer acid to induce chemical cross-linking to improve the melt strength, amine-based, phenolic, phosphorus, sulfur-based, antioxidants in the form of metal complexes, hydroxy Various additives such as benzophenone, hydroxybenzotriazole, acrylate substituent, HINDDERED AMINE type UV stabilizer, antistatic agent, abrasion resistance, filler, pigment, etc. are added during polymerization or dry blended before molding. The performance can be maintained even if

5 to 20 parts by weight of a halogenated polyol and 5 to 20 parts by weight of polypentabromobenzyl acrylate represented by the following general formula (III) based on 100 parts by weight of the polyetherester block copolymer prepared by the above method 2 to 10 parts by weight, 1 to 10 parts by weight of silica can be obtained to obtain an excellent flame retardant polyether ester block copolymer composition, wherein the bromine content of polypentabromobenzyl acrylate is 60 to 75% and the melting range is 200 to The thing of about 5,000-150,000 was used for 230 degreeC and molecular weight. This component is a solid flame retardant that is insoluble in ordinary organic solvents such as lower alcohols, ethers, chlorinated hydrocarbons, ketones, and the like. Antimony trioxide is a known compound that is used as a halogen compound and has a synergistic effect in flame retarding plastics. In addition, silica exhibits an excellent effect as a load generation inhibitor during plastic combustion.

The content of the flame retardant required for flame retardation of the polyether ester block copolymer may vary depending on the flame retardant level, and the higher the content of the flame retardant, the higher the flame retardant effect can be obtained. The flame retardancy above VO grade of UL94 standard is not required and the probability of lowering the flexibility and rubber characteristics of the polyether ester block copolymer due to the excessive injection of other materials other than resin is high. This is incomplete. In addition, when silica having a particle diameter of 0.1 to 0.5 mu is used, the formation of a drop with a flame is suppressed, and at the same time, a sufficient flame retardant effect is obtained even with a relatively small flame retardant. However, the more polybromobenzyl acrylate, antimony trioxide and silica is used, the lower the elastic recovery rate or flexibility, which is inherent to the polyether ester block copolymer, is required. Most preferred.

In the production of flame retardant polyether ester block copolymer, in the present invention, a method of preparing a polyether ester block copolymer base resin in a polymerization process and adding and dispersing the four flame retardant additives in powder form is used. As a method, a flame-retardant polyether ester block copolymer is prepared by a screw-type hot melt mixing process in which a resin and an additive are directly mixed and processed.

In the composition of the present invention, it is also preferable to use a heat-resistant or weather-resistant agent as necessary. As the heat-resistant agent, a sterically hindered phenol or an arylamine is effective, and it is also useful to mix and use a thiodipropionic acid ester or a phosphate ester of a sulfur compound. Do. As the weather resistance agent, ultraviolet absorbers or steric amines that are steric hindrance may be used as the light stabilizer. In addition, additives commonly used, such as pigments, reinforcing agents, fillers, heat resistant agents, plasticizers and mold release agents, may be used.

The processing method of the composition of the present invention is various and can be injection molding, extrusion molding and extrusion molding, and can be easily used for wire coatings, hoses, belts, tires and sports articles that require excellent flame retardancy, molding processability and rate. have.

Hereinafter, the present invention will be described in more detail with reference to Examples.

Example 1

42.0% by weight of poly (tetramethylene oxide) glycol having an average molecular weight of 1,000 in a conventional polyester reaction tube made of stainless steel, 34.0% of dimethyl terephthalate, 23.65% by weight of 1,4-butanediol, 0.2% by weight of tetrabutyl titanate, Heat-resistant mixture, ie 20 g of 3,7-dioctylphenothiazine, 40 g of dilaurylthiodipropionate and 1,1,3-tris (2-methyl-4-hydroxy-5-tert-butylphenyl) 0.15% by weight of a heat-resistant mixture consisting of 24 g of butane was added thereto, heated at room temperature, raised to 210 ° C. for 90 minutes, and methanol was allowed to flow while reacting for 30 minutes.

After the methanol was completely discharged, the reaction tube temperature was reduced to 250 ° C. and the reaction tube pressure was reduced to 0.5 mmHg over 60 minutes, and the condensation polymerization was carried out for 50 minutes while the excess 1,4-butanediol component was discharged out of the reaction system. The stirring was stopped to break the vacuum condition with nitrogen to obtain a polyether ester block copolymer.

[Examples 2 to 4 (Comparative Examples 1 to 7)]

The composition was carried out in the same manner as in Example 1, except that the composition of the flame retardant was as shown in Table 1 below.

[Test Example 1]

The polyether ester block copolymers prepared in Examples and Comparative Examples were vacuum dried at 100 ° C. for 6 hours, dissolved in orthochlorophenol at 30 ° C. to measure the intrinsic viscosity, and the differential calorimetry was performed at 20 ° C./min. The crystal melting point was measured at room temperature, and the inherent viscosity was 2.43 dl and the crystal melting point was 173 ° C.

The flame retardant additive according to the following Table 1 was added to the polyether ester block copolymer, and flame retardant pellets were prepared using a screw-type heat melting mixer, followed by drying at 100 ° C. for 6 hours. Test specimens for physical properties were prepared and evaluated, and the results are shown in Table 1 below.

1) Flame retardant

In accordance with the UL 94 standards, specimens of 3.2 mm thickness and 1.6 mm thickness were fabricated and subjected to combustion testing and evaluation.

2) Precipitation of Flame Retardant

During injection molding, the inner surface of the mold was visually observed to determine precipitation of the flame retardant.

3) Blooming phenomenon

Using disc specimens 3.2 mm thick and 102 mm in diameter, 100 hours in a hot air oven at 150 ° C, 200 hours in a humidity chamber with a relative humidity of 90% and a temperature of 95 ° C for 200 hours, and then the surface state of the specimen was visually observed. Observation was made.

4) Mechanical Properties

Tensile strength was measured by preparing tensile strength test specimens in accordance with ASTM D-638, and flexural modulus was measured by preparing specimens for bending strength in accordance with ASTM D-790.

TABLE 1

PEEBCP: Polyetherester Block Copolymer

M-125: Ixol M-125

RF230: Thermoline RF230

PPBBA: Polypentabromobenzyl acrylate

ATOX: antimony trioxide

SILI: Silica

Tensile Strength Unit: ㎏ / ㎠

Elongation Unit:%

Flexural modulus unit: ㎏ / ㎠

The results of flame retardant measurement (UL-94) are based on the following table 2.

TABLE 2

The total number of specimens was five, ignited twice for one specimen, laid underneath the specimen, and observed to be ignited by falling sparks.

UL-94 HB Requirements

After spark ignition in the horizontal combustion test, the combustion speed of the flame should be within 2.5 "/ min (1/8" standard) and the combustion should stop within 4 ".

[Examples 5 to 8 (Comparative Examples 8 to 14)]

In the preparation of the polyether ester block copolymer in Example 1, the preparation composition was changed as in Table 3 below. As a result, the crystal melting point was 208 ° C., and the basic resin having an intrinsic viscosity of 1.37 dl / g was obtained. Table 4 shows the results of evaluating the addition of the flame retardant additive according to the composition shown in Table 4 using the basic resins obtained in Examples and Comparative Examples.

TABLE 3

TABLE 4

Claims (2)

In preparing a flame retardant polyether ester block copolymer, 5 to 20 parts by weight of a halogenated polyol, 5 to 20 parts by weight of polypentabromobenzyl acrylate, and 2 to 10 parts by weight of antimony trioxide based on 100 parts by weight of a polyetherester block copolymer A method for producing a flame retardant polyether ester block copolymer characterized by adding 1 to 10 parts by weight of silica and silica. The method according to claim 1, wherein the halogenated polyol component comprises at least 45% by weight of a halogen component, and the halogen component generated during combustion is at least 5% by weight.