JPH1025337A - Thermoplastic polyester resin and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a thermoplastic polyester resin which has a specific structural unit, shows excellent flame retardancy and is useful as an injection molding material. SOLUTION: This resin contains (A) (poly)ester units, (B) (poly)melamine units and, when necessary, (C) polyether units. The proportions of individual components are 99.5-20wt.% of the unit (A), 0.5-70wt.% of the unit (B) and 0-79.5wt.% of the unit (C) based on the whole weight of the units (A), (B) and (C). This resin is produced by using an extruder or a continuous reaction tank to carry out the polycondensation reaction in which the components constituting the unit (A), the components constituting the unit (B), and, when necessary, the components constituting the unit (C) are melt-mixed and the reaction system is evacuated preferably to a pressure lower than 55kPa.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a thermoplastic polyester resin and a method for producing the same.

[0002]

2. Description of the Related Art Thermoplastic polyester resins represented by polyethylene terephthalate and polytetramethylene terephthalate are widely used as fibers, films, molding materials, etc. because of their excellent mechanical and electrical properties. . For these uses, melamine-based resins, which are thermosetting resins, are also used because of their excellent flame retardancy and moisture resistance. Also, a resin composition in which a melamine compound is blended with a polyester resin has been proposed. For example, JP-A-49-106536 and JP-A-51-50943 disclose a thermosetting coating composition containing a polyester resin and a melamine compound, and JP-A-1-92218. Discloses a composition for a heat-resistant adhesive comprising a polyalkylene terephthalate, a melamine resin and an epoxy-modified resin. Further, JP-A-63-170453 discloses that a polyester resin is added to a melamine resin for the purpose of improving the toughness and the like of the melamine resin.
195765 proposes the addition of a brominated flame retardant and a methylolmelamine resin for the purpose of improving the flame retardancy of polybutylene terephthalate.

[0003]

However, simply blending a polyester resin and a melamine compound results in a decrease in mechanical properties. When a melamine compound is added for the purpose of imparting flame retardancy, it is necessary to add a large amount of the melamine compound.

Accordingly, an object of the present invention is to provide a novel thermoplastic polyester resin excellent in flame retardancy and the like, which can be suitably used as an injection molding material and the like, and a method for producing the same.

[0005]

In order to achieve the above object, the thermoplastic polyester resin according to the present invention comprises a (poly) ester unit (A), a (poly) melamine compound unit (B), and If necessary, it contains a polyether unit (C).

In this specification, (poly) is
It means that any of a monomer, a condensate and a polycondensate may be used. Further, the (poly) condensate means that any of a condensate and a polycondensate may be used.

The (poly) ester-based unit (A) comprises a divalent or higher carboxylic acid residue, a divalent or higher valent alcohol residue and / or a divalent or higher phenol residue. (Poly)
The ester unit (A) is a divalent or higher carboxylic acid and at least one derivative thereof capable of forming an ester,
It is obtained by polycondensation of a dihydric or higher alcohol, its derivative having an ester forming ability, and at least one of dihydric or higher phenol and its derivative having an ester forming ability by a known method.

The divalent or higher carboxylic acid which is one of the components (a) constituting the (poly) ester unit (A) includes a divalent or higher aromatic carboxylic acid having 8 to 22 carbon atoms, 3-12 divalent or higher valent aliphatic carboxylic acid, carbon number 8
And a divalent or higher valent alicyclic carboxylic acid having from 15 to 15, and derivatives thereof having an ester-forming ability. 8 to 2 carbon atoms
Specific examples of the divalent or higher aromatic carboxylic acid of 2 include terephthalic acid, isophthalic acid, phthalic acid, naphthalenedicarboxylic acid, bis (p-carboxyphenyl) methaneanthracenedicarboxylic acid, 4,4′-diphenyldicarboxylic acid, 1,2-bis (phenoxy) ethane-4,4'-
Examples include dicarboxylic acid, diphenylsulfone dicarboxylic acid, trimesic acid, trimellitic acid and pyromellitic acid. Specific examples of the divalent or higher aliphatic carboxylic acid having 3 to 12 carbon atoms include succinic acid, adipic acid, sebacic acid,
Decanedicarboxylic acid, azelaic acid, dodecanedicarboxylic acid and maleic acid. 2 of carbon number 8-15
Specific examples of the alicyclic carboxylic acid having a valency of not less than 1,3-
Examples include cyclohexanedicarboxylic acid and 1,4-cyclohexanedicarboxylic acid. These divalent or higher carboxylic acids may be used alone or in combination of two or more as needed.

The dihydric or higher alcohol as one of the components (a) constituting the (poly) ester-based unit (A) is an aliphatic compound having 2 to 15 carbon atoms or 6 to 20 carbon atoms.
Alicyclic compounds having two or more hydroxyl groups and derivatives thereof having an ester-forming ability. Further, as the dihydric or higher phenol which is one of the components (a) constituting the (poly) ester-based unit (A),
Examples thereof include aromatic compounds having 6 to 40 carbon atoms and having two or more hydroxyl groups, and derivatives thereof having an ester-forming ability. Specific examples of these alcohols or phenols include ethylene glycol, propylene glycol, butanediol, hexanediol, decanediol, neopentyl glycol, cyclohexanedimethanol, cyclohexanediol, and 2,2′-bis (4
-Hydroxyphenyl) propane, 2,2′-bis (4
-Hydroxycyclohexyl) propane, hydroquinone, glycerin, pentaerythritol, diethylene glycol and triethylene glycol. Any of these dihydric or higher alcohols and dihydric or higher phenols may be used singly, and may be used as necessary.
More than one species may be used in combination.

The (poly) ester-based unit (A) may be a copolymer unit in which other known components are copolymerized with the (poly) ester as long as the properties are not impaired. Other components in this case include oxyacids such as p-oxybenzoic acid and derivatives having the ability to form esters, ε-caprolactone, methyl-ε-caprolactone, dimethyl-ε-caprolactone, trimethyl-ε-caprolactone, β -Cyclic lactones such as propiolactone, bivalolactone, γ-valerolactone, enantholactone, caprylolactone, and (poly) condensates thereof.

Specific examples of the (poly) ester unit (A) include (poly) ethylene terephthalate unit, (poly) propylene terephthalate unit, (poly) butylene terephthalate unit, (poly) hexamethylene terephthalate unit, and (poly) Cyclohexane dimethylene terephthalate unit, (poly) ethylene naphthalate unit,
(Poly) butylene naphthalate unit, (poly) ethylene isophthalate unit, (poly) butylene isophthalate unit, (poly) hexamethylene isophthalate unit,
(Poly) cyclohexane dimethylene isophthalate units, (poly) ethylene adipate units and (poly) butylene adipate units.

The (poly) melamine compound unit (B) is
It comprises a melamine compound residue and / or a melamine compound (poly) condensate residue. The component (b) constituting the (poly) melamine compound unit (B) includes a melamine compound and a melamine compound (poly) condensate. Here, the melamine-based compound means melamine and its derivatives. Specific examples of the derivative include monomethylol melamine, dimethylol melamine, trimethylol melamine, tetramethylol melamine, pentamethylol melamine, methylol melamines such as hexamethylol melamine, and methylated methylol melamine, ethylated methylol melamine, butylated methylol melamine And alkylated methylolmelamines. Specific examples of the melamine-based compound (poly) condensate include (poly) condensates of methylolmelamines, and (poly) condensates obtained by reacting melamine or methylolmelamines with a dihydric or higher alcohol. . Among the components (b) constituting the (poly) melamine-based compound unit (B), preferred are melamine, methylolmelamines, (poly) condensates of methylolmelamines, and dihydric or higher alcohols with these. Or a (poly) condensate with a divalent or higher phenol. Each of these melamine-based compounds and melamine-based compound (poly) condensates may be used alone or in combination of two or more as needed.

The (poly) melamine compound unit (B) is
It may be a unit constituting the main chain of the copolymer, or a unit dispersed in the form of particles and bonded to the (poly) ester-based unit (A) and / or the polyether unit (C).
Examples of the particle shape in the latter case include a needle shape, a spheroidal shape, a spherical shape, a plate shape, a polyhedral shape, and shapes similar thereto. The average particle diameter of the particles is preferably 1000 μm or less from the viewpoint of the surface properties and mechanical properties of the molded article, and is preferably 500 μm or less.
μm or less is more preferable, and 200 μm or less is most preferable.

Specific examples of the component (c) constituting the polyether unit (C) include polyethylene glycol, polypropylene glycol, polytetramethylene glycol, poly (ethylene oxide / propylene oxide) copolymer, and poly (ethylene oxide / tetrahydrofuran) Copolymers, poly (ethylene oxide / propylene oxide / tetrahydrofuran) copolymers and alkylene oxide addition polymers of bisphenols.
Examples of the alkylene oxide addition polymer of bisphenols include ethylene oxide addition polymer of bisphenol A, propylene oxide addition polymer of bisphenol A, tetrahydrofuran addition polymer of bisphenol A, (ethylene oxide / propylene oxide) addition polymer of bisphenol A, and bisphenol. Examples thereof include an ethylene oxide addition polymer of S, a propylene oxide addition polymer of bisphenol S, a tetrahydrofuran addition polymer of bisphenol S, and a (ethylene oxide / propylene oxide) addition polymer of bisphenol S.
As the component (c) constituting the polyether unit (C), one type may be used alone, or two or more types having different molecular weights or the like may be used in combination as needed.

The thermoplastic polyester resin according to the present invention includes a (poly) ester unit (A), a (poly) melamine compound unit (B) and a polyether unit (C).
Based on the total amount of (poly) ester units (A)
9.5 to 20% by weight, 0.5 to 70% by weight of (poly) melamine compound unit (B), polyether unit (C)
Is preferably 0 to 79.5% by weight. By including the polyether unit (C), the thermoplastic polyester resin according to the present invention is softened or elastomerized. The intrinsic viscosity (intrinsic viscosity (IV) at 25 ° C. in a mixed solvent having a phenol / tetrachloroethane weight ratio of 1: 1) of the thermoplastic polyester resin according to the present invention is determined by the mechanical properties and fluidity. In terms of 0.3
0 to 2.00 d1 / g is preferable, and 0.40 to 1.80.
d1 / g is more preferred, and 0.50 to 1.60 d1 / g
Is most preferred. If the intrinsic viscosity is too low, the mechanical properties deteriorate, while if the intrinsic viscosity is too high, the fluidity decreases.

[0016] The thermoplastic polyester resin according to the present invention can be prepared by, for example, using an extruder, a continuous reaction tank, a batch reaction tank, or the like, with the component (a) constituting the (poly) ester-based unit (A); After the component (b) constituting the (poly) melamine-based compound unit (B) and the component (c) constituting the polyether unit (C) are melt-mixed if necessary, the pressure in the reaction system is reduced. And polycondensation. Instead of component (a) and component (c), (poly)
A copolymer obtained by previously copolymerizing an ester and a polyether may be used. The reduced pressure for starting the polycondensation reaction is preferably 55 kPa or less.

As a method for adding the (poly) melamine compound as the component (b) constituting the (poly) melamine compound unit (B) to the reaction system, a solid (poly) melamine compound is directly added. And a method in which the (poly) melamine compound is dissolved in an appropriate solvent and then added, but the (poly) melamine compound can be dissolved at a reaction temperature of the polycondensation or lower, and (Poly) ester-based unit (A), constituent (a), (poly) melamine-based compound unit (B), constituent (b), polyether unit (C) and constituent thereof The most preferred method is to add the compound to the reaction system together with an organic compound capable of undergoing a condensation reaction with at least one of the components (c).

Specific examples of the above-mentioned organic compounds include at least one of divalent or higher carboxylic acids and derivatives thereof having an ester forming ability, divalent or higher alcohols, divalent or higher phenols and their ester forming ability. (Poly) esters containing at least one hydroxyl group obtained by condensation with at least one derivative having the formula (I), and polyethers. A mixture of a (poly) ester and a polyether may be used. Further, a mixture of the (poly) ester, the polyether or a mixture thereof with the component (a) constituting the (poly) ester-based unit (A) may be used. Mixtures may be used. As the above-mentioned divalent or higher carboxylic acid, divalent or higher alcohol and divalent or higher phenol,
The above-mentioned divalent or higher carboxylic acid used as the component (a) constituting the (poly) ester-based unit (A),
Polyhydric alcohols and dihydric phenols can be used. Specific examples of the above (poly) ester include bishydroxyethylene terephthalate, bishydroxyethylene isophthalate, bishydroxybutylene terephthalate, bishydroxybutylene isophthalate, methylhydroxyethylene terephthalate, methylhydroxybutylene terephthalate, and polycondensates thereof. No. Examples of the polyether further include diethylene glycol and triethylene glycol, in addition to those described above as the component (c) constituting the polyether unit (C).

The polycondensation reaction may be carried out without a catalyst, or may be carried out by adding a polycondensation catalyst before starting the polycondensation. Examples of the polycondensation catalyst include antimony compounds such as antimony trioxide, germanium compounds such as germanium dioxide, titanium compounds such as titanium tetrabutoxide, tin compounds such as tin isopropoxide, and cobalt compounds such as cobalt acetate.

The thermoplastic polyester resin according to the present invention can be used alone, but can also be used as a mixture with another resin. Other resins in this case include other thermoplastic polyester resins, liquid crystal polyester resins, polyester ester elastomer resins, polyester ether elastomer resins,
Polycarbonate resin, polyolefin resin, polyamide resin, polystyrene resin, polyphenylene sulfide resin, polyphenylene ether resin, polyacetal resin, polysulfone resin, polyarylate resin, fluorinated polyolefin resin (polytetrafluoroethylene, etc. ), Rubber-like elastic bodies, unsaturated polyester resins, epoxy resins, melamine resins, urea resins and phenol resins.

The thermoplastic polyester resin according to the present invention is preferably added with an antioxidant such as phenol or thioether and a heat stabilizer such as phosphorus.

If necessary, conventionally known stabilizers, lubricants, release agents, plasticizers, flame retardants, flame retardant assistants, ultraviolet absorbers, light stabilizers, pigments, dyes, antistatic agents, conductive agents A property imparting agent, a dispersant, a compatibilizer, an antibacterial agent, and the like may be added.

The method of molding the thermoplastic polyester resin according to the present invention is not particularly limited, and molding methods generally applied to thermoplastic resins, for example, injection molding, blow molding, extrusion molding, vacuum molding Press molding, calender molding and the like can be used.

[0024]

EXAMPLES The present invention will be described in detail with reference to examples, but the present invention is not limited to the examples. In addition,
Hereinafter, “parts” means parts by weight.

Example 1 Bishydroxyethylene terephthalate 5 was placed in a pressure vessel (volume: 7 liters: manufactured by Japan Pressure Glass Company) equipped with a distilling tube and a stirrer under a nitrogen stream.
Then, 00 g was added, and the mixture was heated and melted at 120 ° C., and 150 g of dimethylolmelamine was dissolved therein. Then
Polyethylene terephthalate (intrinsic viscosity 0.65) 10
After adding 00 g and 5 g of a hindered phenol-based stabilizer (product code “ADK STAB AO-60” manufactured by Asahi Denka Co., Ltd.), the temperature was raised to 270 ° C. After the temperature was raised, 0.2 g of titanium tetrabutoxide was added, and the pressure was reduced to 133 Pa.
Stirring was continued for 2 hours to terminate the reaction, thereby obtaining a thermoplastic polyester resin according to the present invention. This resin was transparent and had an intrinsic viscosity of 0.64. FIG. 1 shows the infrared absorption spectrum of the resin.

(Example 2) Bishydroxyethylene terephthalate 9 was placed in a pressure vessel (volume: 7 liters: manufactured by Japan Pressure Glass Company) equipped with a distilling tube and a stirrer under a nitrogen stream.
Then, the mixture was heated to 120 ° C. and melted, and 90 g of dimethylolmelamine was dissolved therein. Then, polyethylene terephthalate (intrinsic viscosity 0.65) 600
g, polyethylene glycol (number average molecular weight: about 100
0) 540 g and hindered phenol-based stabilizer (Asahi Denka Co., Ltd., product code "Adeka Stab AO-60") 5 g
Was added, and the temperature was raised to 250 ° C. After the temperature was raised, 0.2 g of titanium tetrabutoxide was added, the pressure was reduced to 133 Pa, the stirring was continued for 2 hours, and the reaction was terminated to obtain a thermoplastic polyester resin according to the present invention. This resin was transparent and had an intrinsic viscosity of 0.86. FIG. 2 shows the infrared absorption spectrum of this resin.

Example 3 3030 g of dimethyl terephthalate, 1940 g of ethylene glycol, and ethylene oxide addition weight of bisphenol A were placed in a pressure vessel (volume: 7 liters: Japan Pressure Glass) equipped with a distilling tube and a stirrer under a nitrogen stream. Combined (number average molecular weight about 1000) 75
Then, 0 g, 9 g of a hindered phenol-based stabilizer (manufactured by Asahi Denka Co., Ltd., product code "ADK STAB AO-60") and 0.2 g of titanium tetrabutoxide were added, and the mixture was heated to 200 ° C to distill off methanol. Next, after the temperature was raised to 265 ° C., polyethylene glycol (number average molecular weight: about 2
00) A solution in which 190 g of trimethylolmelamine was dissolved was added to 760 g, the pressure was reduced to 133 Pa, the stirring was continued for 2 hours, and the reaction was terminated to obtain a thermoplastic polyester resin according to the present invention. This resin was transparent and had an intrinsic viscosity of 0.7. FIG. 3 shows the infrared absorption spectrum of this resin.

Example 4 Bishydroxyethylene terephthalate 8 was placed in a pressure vessel (volume: 7 liters: manufactured by Japan Pressure Glass Company) equipped with a distilling tube and a stirrer under a nitrogen stream.
After charging 10 g, the mixture was melted by heating to 120 ° C., 270 g of dimethylolmelamine was dissolved, cooled to room temperature and solidified, and then pulverized by a pulverizer. 30 parts of the pulverized material thus obtained and 0.02 part of titanium tetrabutoxide are dry-blended with 100 parts of polyethylene terephthalate (intrinsic viscosity 0.85), and a coaxial twin-screw extruder (manufactured by Nippon Steel Works, product code "TEX-30")
The mixture was extruded and kneaded at a cylinder temperature setting of 270 ° C. to cause a reaction, thereby obtaining a thermoplastic polyester resin according to the present invention. In this resin, units derived from dimethylolmelamine were dispersed in particles. The intrinsic viscosity of this resin was 0.8. This resin is 1,1,1,3
Dissolved in 3,3-hexafluoro-2-propanol,
Particles consisting of units derived from dimethylolmelamine were filtered off. FIG. 4 shows the infrared absorption spectrum of the particles. For comparison, FIG. 5 shows an infrared absorption spectrum of a resin obtained by curing only dimethylolmelamine.
FIG. 4 shows an absorption spectrum derived from polyethylene terephthalate as well as an absorption spectrum of the cured dimethylolmelamine shown in FIG. From this fact, it is understood that in this resin, the (poly) ester unit and the (poly) melamine compound unit are bonded.

Comparative Example 1 A thermoplastic polyester resin was obtained in the same manner as in Example 1 except that dimethylolmelamine was not used. The intrinsic viscosity of this resin is 0.6
It was 0.

<Flame Retardancy Test> The thermoplastic polyester resins obtained in Example 1 and Comparative Example 1 were subjected to the following flame retardancy tests.

Each resin was pelletized, dried at 100 ° C. for about 4 hours with a hot air drier, and then set at a cylinder temperature of 280 ° C. and a mold temperature of 100 ° C. using a 50 t injection molding machine. A test piece was prepared. Next, the flame retardancy of these test pieces was evaluated in accordance with the flame retardancy test standard of LOIASTM D2863. The LOI (minimum oxygen concentration) of the resin obtained in Example 1 was 23.2%, whereas that of the resin obtained in Comparative Example 1 was 18.2%.
From these results, it is understood that the thermoplastic polyester resin according to the present invention has excellent flame retardancy.

[0032]

The present invention provides a thermoplastic polyester resin suitable for use as a flame-retardant injection molding material and the like and a method for producing the same.

[Brief description of the drawings]

FIG. 1 is an infrared absorption spectrum of a thermoplastic polyester resin produced in Example 1.

FIG. 2 is an infrared absorption spectrum of a thermoplastic polyester resin produced in Example 2.

FIG. 3 is an infrared absorption spectrum of a thermoplastic polyester resin produced in Example 3.

FIG. 4 is an infrared absorption spectrum of a thermoplastic polyester resin produced in Example 4.

FIG. 5 is an infrared absorption spectrum of a resin obtained by curing only dimethylolmelamine.

Claims (8)

[Claims] 1. A (poly) ester-based unit (A), (poly)
A thermoplastic polyester resin containing a melamine compound unit (B) and, if necessary, a polyether unit (C). 2. (Poly) ester units (A) and (poly)
Based on the total amount of the melamine-based compound unit (B) and the polyether unit (C), 99.5 to 20% by weight of the (poly) ester-based unit (A) and 0% by weight of the (poly) melamine-based compound unit (B). 2. The thermoplastic polyester resin according to claim 1, which contains 0.5 to 70% by weight and 0 to 79.5% by weight of a polyether unit (C). 3. A component (a) constituting the (poly) ester-based unit (A), a component (b) constituting the (poly) melamine-based compound unit (B), and if necessary, a polyether (C) And melt-mixing the component (c) to form a reaction system, and then reducing the pressure in the reaction system to carry out polycondensation, thereby producing a thermoplastic polyester resin. 4. The method for producing a thermoplastic polyester resin according to claim 3, wherein the polycondensation is carried out under a reduced pressure of 55 kPa or less. 5. The component (b) constituting the (poly) melamine-based compound unit (B) can be dissolved at a reaction temperature at the time of polycondensation or lower, and the (poly) ester-based unit (A) Condensation with at least one of component (a), (poly) melamine-based compound unit (B), component (b), polyether unit (C) and component (c) The method for producing a thermoplastic polyester resin according to claim 3 or 4, wherein the thermoplastic polyester resin is added to the reaction system together with the organic compound capable of reacting. 6. An organic compound comprising at least one of divalent or higher carboxylic acids and derivatives thereof having an ester-forming ability, and divalent or higher alcohols, divalent or higher phenols and derivatives of these having an ester-forming ability. At least one
The method for producing a thermoplastic polyester resin according to claim 5, which is a (poly) ester containing a hydroxyl group obtained by subjecting a seed to a condensation reaction. 7. The method for producing a thermoplastic polyester resin according to claim 5, wherein the organic compound is a polyether. 8. The process for producing a thermoplastic polyester resin according to claim 3, wherein a polycondensation catalyst is added to the reaction system before the start of the polycondensation.