JP2010132832A - Flame-retardant polyester resin composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a flame-retardant polyester resin composition with flame retardancy, mechanical properties, and heat resistance. <P>SOLUTION: This polyester resin composition includes a mixture of: a polyester resin (A) which contains 50-90 mol% of terephthalic acid as a polycarboxylic acid component and 70-100 mol% of the total of 1,4-butane diol, ethylene glycol, and diethylene glycol as a polyhydric alcohol component; and melamine (B), wherein the resin composition does not spoil original characteristics of the polyester resin (A), and attains excellent flame retardancy, mechanical properties, and heat resistance with a reduced amount of addition of an inorganic flame retardant relative to an amount conventionally examined. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a flame retardant polyester resin composition having flame retardancy, mechanical properties, and heat resistance.

  Polyester resins with excellent insulation and flexibility are attracting attention as alternative materials for vinyl chloride resins. However, polyester resins are generally easy to burn, so it is difficult to make these resins flame-retardant. It is necessary to add flame retardant to make it flame retardant.

As flame retardants for polyester resins, halogen flame retardants such as decabromodiphenyl ether and hexabromodiphenyl have been used. Halogen flame retardants generate harmful gases such as dioxins during combustion. In some cases, it is also a problem in terms of safety during waste incineration and thermal recycling.
Phosphorus compounds are also conceivable, but not only are there problems in terms of safety and environmental harmony, but especially when a phosphorus compound is added to a polyester resin, the heat resistance decreases due to plasticization, and the molded product of the phosphorus compound. Since bleeding to the surface occurs, it cannot be said to be a practically preferable technique.

  Therefore, the present inventor has focused on nitrogen compounds, particularly melamine, as non-halogen / non-phosphorus flame retardants used in polyester resins. The use of nitrogen compounds, particularly melamine, as a flame retardant is described in, for example, Patent Documents 1-4.

JP 54-112958 A Japanese Patent Publication No. 60-33850 Japanese Patent Publication No.59-50184 Japanese Examined Patent Publication No. 62-39174

  Since melamine starts decomposing at 220 to 250 ° C., it has a problem that melamine decomposes and causes poor molding at the molding temperature of general polyester resins such as PET and PBT.

  Therefore, in the present invention, by preparing melamine as a flame retardant in a specific polyester resin to prepare a flame retardant polyester resin composition, melamine may be decomposed during molding to cause defective molding. In addition, the present invention intends to provide a new flame retardant polyester resin composition that can maintain the mechanical properties and heat resistance of the polyester resin.

  The present invention relates to a flame-retardant polyester resin containing a mixture of a polyester resin (A) having a glass transition temperature Tg of −20 ° C. to 40 ° C. and a crystal melting temperature Tm of 140 ° C. to 190 ° C. and melamine. Proposed is a flame retardant polyester resin composition, which is a composition, wherein the proportion of melamine in the flame retardant polyester resin composition is 20 to 60% by mass.

The polyester resin (A) having a glass transition temperature Tg of −20 ° C. to 40 ° C. and a crystal melting temperature Tm of 140 ° C. to 190 ° C. has a melting point as compared with general polyester resins such as PET and PBT. Since it is low and can be molded at a temperature lower than the temperature at which melamine decomposes, it is possible to eliminate the occurrence of molding defects due to decomposition of melamine during molding. In addition, excellent flexibility and mechanical properties can be obtained.
By adding melamine (B) to such a specific polyester resin (A), the additive amount is lower than that of conventionally studied inorganic flame retardants without impairing the inherent properties of the polyester resin. In addition, excellent flame retardancy, mechanical properties, and heat resistance can be obtained.

  Hereinafter, a flame-retardant polyester-based resin composition (hereinafter referred to as “the present flame-retardant PEs resin composition”) as an example of an embodiment of the present invention will be described. However, the scope of the present invention is not limited to the embodiments described below.

<This flame-retardant PEs resin composition>
The flame retardant PEs resin composition is a flame retardant polyester resin composition containing a mixture of a polyester resin (A) and melamine, and preferably further contains a polyester resin (B). System resin composition.

(Polyester resin (A))
The polyester resin (A) is a polyester resin that is a polycondensation polymer of a polyvalent carboxylic acid and a polyhydric alcohol.
Specific examples of the polyvalent carboxylic acid include terephthalic acid, isophthalic acid, succinic acid, adipic acid, sebacic acid, dodecanedioic acid and the like.
Specific examples of the polyhydric alcohol include ethylene glycol, propylene glycol, 1,4-butanediol, 1,6-hexanediol, cyclohexanediol, polyoxylene glycol, polytetramethylene ether glycol and the like.
Above all, a co-polymer consisting of at least one polycarboxylic acid component selected from terephthalic acid, isophthalic acid, and adipic acid and at least one polyhydric alcohol component selected from 1,4-butanediol and ethylene glycol. It is preferably a coalescence.

In the polyester resin (A), the proportion of terephthalic acid in the polyvalent carboxylic acid component is preferably 50 to 90 mol%. Since the polyester resin (A) having such a composition has a lower melting point than general polyester resins such as PET and PBT, and can be molded at a temperature lower than the temperature at which melamine starts to decompose, It is possible to eliminate the occurrence of molding defects due to decomposition of melamine during molding. In addition, excellent flexibility and mechanical properties can be obtained.
From this viewpoint, the polyester resin (A) preferably contains 55 mol% or more, particularly 60 mol% or more of terephthalic acid as the polyvalent carboxylic acid component, and also contains 85 mol% or less, particularly 80 mol% or less. Is more preferable.
However, it is not intended to limit the polyester resin in which the proportion of terephthalic acid in the polyvalent carboxylic acid component is 50 to 90 mol%.

In the polyester resin (A), it is preferable that the total ratio of 1,4-butanediol and ethylene glycol in the polyhydric alcohol component is 70 to 100 mol%. If it is a polyester-type resin (A) which has such a composition, the outstanding softness | flexibility, mechanical characteristics, and also heat resistance can be acquired.
From this viewpoint, the polyester-based resin (A) preferably contains 75 mol% or more, particularly 80 mol% or more, and 100 mol% of 1,4-butanediol and ethylene glycol in total as the polyhydric alcohol component. Further preferred.
However, the polyhydric alcohol component may include any one of 1,4-butanediol, ethylene glycol, and diethylene glycol, or may include two or more.

  The glass transition temperature Tg of the polyester resin (A) is preferably -20 to 40 ° C. When the Tg of the polyester resin (A) is within a temperature range, a flame retardant polyester resin composition excellent in mechanical properties such as flexibility and tensile strength can be prepared. From this viewpoint, the Tg of the polyester-based resin (A) is particularly preferably −15 ° C. or higher, particularly preferably −10 ° C. or higher, and particularly preferably 35 ° C. or lower, especially 30 ° C. or lower.

  The crystal melting temperature Tm of the polyester resin (A) is preferably 140 to 190 ° C. When the crystal melting temperature Tm of the polyester resin (A) is within such a range, a flame retardant polyester resin composition having excellent mechanical properties such as flexibility and tensile strength can be prepared. From this viewpoint, the Tm of the polyester-based resin (A) is particularly preferably 145 ° C. or higher, particularly 150 ° C. or higher, and particularly preferably 185 ° C. or lower, especially 180 ° C. or lower.

  It is preferable that the heat of crystal fusion ΔHm of the polyester resin (A) is 20 to 40 J / g. If ΔHm of the polyester resin (A) is within such a range, a flame-retardant polyester resin composition having excellent mechanical properties such as flexibility and tensile strength can be prepared. From this point of view, ΔHm of the polyester-based resin (A) is particularly preferably 22 J / g or more, more preferably 25 J / g or more, and particularly preferably 38 J / g or less, especially 35 J / g or less.

The mass average molecular weight of the polyester resin (A) is preferably 10,000 to 300,000. If the mass average molecular weight of the polyester-based resin (A) is within such a range, flexibility can be obtained, and the melt viscosity is appropriate.
From this viewpoint, the mass average molecular weight of the polyester-based resin (A) is particularly preferably 20,000 or more, more preferably 30,000 or more, particularly 200,000 or less, especially 150,000 or less. Is more preferable.

The mass average molecular weight can be measured by the following method. The same applies to other resins.
Using gel permeation chromatography, measurement is made at a solvent chloroform, a solution concentration of 0.2 wt / vol%, a solution injection amount of 200 μL, a solvent flow rate of 1.0 ml / min, a solvent temperature of 40 ° C., and a mass average molecular weight in terms of polystyrene is obtained. Can be calculated. The mass average molecular weight of the standard polystyrene used in this case is 2,000,000, 430,000, 110,000, 35,000, 10,000, 40,00, 600.

(Polyester resin (B))
The polyester resin (B) is a polyester resin that is a polycondensation polymer of a polyvalent carboxylic acid and a polyhydric alcohol.

Specific examples of the polyvalent carboxylic acid include terephthalic acid, isophthalic acid, succinic acid, adipic acid, sebacic acid, dodecanedioic acid and the like.
Specific examples of the polyhydric alcohol include ethylene glycol, propylene glycol, 1,4-butanediol, 1,6-hexanediol, cyclohexanediol, polyoxylene glycol, polytetramethylene ether glycol and the like.
Above all, a co-polymer consisting of at least one polycarboxylic acid component selected from terephthalic acid, isophthalic acid, and adipic acid and at least one polyhydric alcohol component selected from 1,4-butanediol and ethylene glycol. It is preferably a coalescence.

In the polyester resin (B), the proportion of terephthalic acid in the polyvalent carboxylic acid component is preferably 20 mol% or more and less than 70 mol%. When the polyester resin (B) having such a composition is blended together with the polyester resin (A), flexibility, particularly excellent elongation can be obtained, which is preferable. From this viewpoint, the polyester resin (B) preferably contains terephthalic acid as a polyvalent carboxylic acid component in an amount of 30 mol% or more, particularly 40 mol% or more, and less than 65 mol%, particularly less than 60 mol%. Is more preferable.
However, it is not intended to limit the polyester-based resin in which the proportion of terephthalic acid in the polyvalent carboxylic acid component is 20 mol% or more and less than 70 mol%.

In the polyester resin (B), the total ratio of 1,4-butanediol and ethylene glycol in the polyhydric alcohol component is preferably 65 to 100 mol%. When the polyester resin (B) having such a composition is blended with the polyester resin (A), the mechanical properties can be further improved without impairing the heat resistance of the polyester resin (A).
From this viewpoint, the polyester-based resin (B) preferably contains 1,4-butanediol and ethylene glycol as a polyhydric alcohol component in a total amount of 70 mol% or more, particularly 75 mol% or more, and particularly 95 mol% or less. Of these, 90 mol% is more preferable.
However, the polyhydric alcohol component may include any one of 1,4-butanediol, ethylene glycol, and diethylene glycol, or may include two or more.

  The glass transition temperature Tg of the polyester resin (B) is preferably −100 or higher and lower than −20 ° C. If the Tg of the polyester resin (B) is within a temperature range, the flexibility, particularly the elongation can be increased by blending with the polyester resin (A), and the effect is a thin film having a thickness of 200 μm or less. Is particularly effective. From this point of view, the polyester resin (B) has a temperature of −90 ° C. or higher, preferably −80 ° C. or higher, and is preferably −25 ° C. or lower, particularly preferably −30 ° C. or lower.

  The crystal melting temperature Tm of the polyester resin (B) is preferably 100 ° C. or higher and lower than 140 ° C. If the crystal melting temperature Tm of the polyester resin (B) is within such a range, a flame retardant polyester resin composition excellent in mechanical properties such as flexibility and tensile strength can be prepared. From this viewpoint, the Tm of the polyester-based resin (B) is particularly preferably 105 ° C. or higher, particularly preferably 110 ° C. or higher, and particularly preferably lower than 135 ° C., particularly preferably lower than 130 ° C.

  The crystal melting heat ΔHm of the polyester resin (B) is preferably 1 J / g or more and less than 20 J / g. If ΔHm of the polyester resin (B) is within such a range, the mechanical properties, particularly elongation and flexibility of the flame retardant polyester resin composition can be further improved. From this viewpoint, the ΔHm of the polyester resin (B) is particularly preferably 5 J / g or more, more preferably 10 J / g or more, and particularly preferably less than 18 J / g, particularly preferably less than 15 J / g.

The mass average molecular weight of the polyester resin (B) is preferably 10,000 to 300,000. If the mass average molecular weight of the polyester-based resin (B) is within such a range, flexibility can be obtained and the melt viscosity is appropriate, so that there is a low possibility that a problem will occur in the molding process.
From this viewpoint, the mass average molecular weight of the polyester-based resin (B) is particularly preferably 20,000 or more, more preferably 30,000 or more, particularly 200,000 or less, especially 150,000 or less. Is more preferable.

The mass average molecular weight can be measured by the following method. The same applies to other resins.
Using gel permeation chromatography, measurement is made at a solvent chloroform, a solution concentration of 0.2 wt / vol%, a solution injection amount of 200 μL, a solvent flow rate of 1.0 ml / min, a solvent temperature of 40 ° C., and a mass average molecular weight in terms of polystyrene is obtained. Can be calculated. The mass average molecular weight of the standard polystyrene used in this case is 20000, 430000, 110000, 35000, 10000, 4000, 600.

(melamine)
Melamine is a kind of organic nitrogen compound having a triazine ring at the center of the structure, and examples thereof include 2,4,6-triamino-1,3,5-triazine. Since melamine generates nonflammable gas at the time of combustion, the flame retardant PEs resin composition can be made flame retardant.
Melamine has a lower decomposition initiation temperature than melamine derivatives (for example, melamine cyanurate, melamine phosphate, etc.) and has no carbonization promoting action, so it is generally difficult to use as a flame retardant. However, when blended with the polyester resin (A) or the polyester resins (A) and (B) of the present invention, the resin can be melt-kneaded at a temperature lower than the decomposition start temperature of melamine, and at the time of combustion, the resin By decomposing melamine prior to decomposition, it is possible to impart excellent flame retardancy due to the endothermic action during sublimation and generation of inert gas.

The average particle size of melamine is preferably 10 μm or less, particularly preferably 0.5 μm to 10 μm. As long as the average particle size of melamine is within this range, melamine does not agglomerate and is uniformly dispersed in the resin composition, so that flame retardancy is not impaired without impairing the mechanical strength of the flame retardant PEs resin composition. Can be improved. From this point of view, the average particle size of melamine is particularly preferably 1.0 μm or more, particularly preferably 1.5 μm or more, particularly preferably 8.0 μm or less, and particularly preferably 6.0 μm or less.
The average particle diameter is a value calculated by using melamine as the equivalent circle diameter.

A surface treatment can be applied to melamine as long as the effects of the present invention are not impaired.
Specific examples of the surface treatment include surface treatment using a silane coupling agent such as epoxy silane, vinyl silane, methacryl silane, amino silane, isocyanate silane, titanate coupling agent, higher fatty acid and the like.
By treating melamine with these surface treatment agents, the dispersibility of melamine can be improved and the flame retardancy of the present flame retardant PEs resin composition can be further improved.

In addition, melamine and other flame retardants or flame retardant aids may be used in combination as long as the effects of the present invention are not impaired.
Specific examples of other flame retardants include, for example, phosphoric acid esters, phosphoric acid ester amides, condensed phosphoric acid esters, phosphazene compounds, phosphorus compounds such as polyphosphates, aluminum hydroxide, magnesium hydroxide, calcium aluminate water Examples thereof include metal hydroxides such as hydrates and tin oxide hydrates.
Specific examples of flame retardant aids include, for example, metal compounds such as zinc stannate, zinc borate, iron nitrate, copper nitrate, and sulfonic acid metal salts, silicone compounds such as dimethyl silicone, phenyl silicone, and fluorine silicone, polytetrafluoro Fluorine compounds such as ethylene can be mentioned.
By using these flame retardants and flame retardant aids in combination, the flame retardancy of the present flame retardant PEs resin composition can be further improved.

(Mixing ratio)
The blending ratio of melamine in the flame retardant PEs resin composition is preferably 20 to 60% by mass. If the blending ratio of melamine in the flame-retardant PEs resin composition is 20% by mass or more, sufficient flame retardancy can be obtained, while if the blending ratio of melamine is 60% by mass or less, mechanical properties. Will not be damaged. From this viewpoint, the blending ratio of melamine in the flame retardant PEs resin composition is particularly preferably 20% by mass or more, and more preferably 30% by mass or more. Moreover, it is especially preferable that it is 50 mass% or less, and it is still more preferable that it is 40 mass% or less especially.

Moreover, when mix | blending a polyester-type resin (B), it is preferable that the mixing ratio of a polyester-type resin (A) and a polyester-type resin (B) is 90: 10-30: 70 by mass ratio. If it is this ratio, a mechanical characteristic can be improved further, without impairing the heat resistance which a polyester-type resin (A) has.
From this viewpoint, the polyester resin (A) and the polyester resin (B) are mixed so that the polyester resin (B) is contained at a ratio of 80:20 or more, particularly 70:30 or more. While it is preferable to mix (B), it is preferable to mix the polyester resin (B) so that the polyester resin (B) is contained in a ratio of 40:60 or less, particularly 50:50 or less.

(Other ingredients)
A carbodiimide compound may be blended with the flame retardant PEs resin composition in order to impart hydrolysis resistance. However, it is not necessary to mix.

Examples of the carbodiimide compound include those having a basic structure represented by the following general formula.
-(N = C = N-R-) n-
(In the above formula, n represents an integer of 1 or more. R represents another organic bond unit. In these carbodiimide compounds, the R portion may be aliphatic, alicyclic, or aromatic. .)
Usually, n is appropriately determined between 1 and 50.

  Specifically, for example, bis (dipropylphenyl) carbodiimide, poly (4,4′-diphenylmethanecarbodiimide), poly (p-phenylenecarbodiimide), poly (m-phenylenecarbodiimide), poly (tolylcarbodiimide), poly (diisopropyl) Examples thereof include phenylene carbodiimide), poly (methyl-diisopropylphenylene carbodiimide), poly (triisopropylphenylene carbodiimide), and the like. The carbodiimide compound is used alone or in combination of two or more.

As a compounding quantity of a carbodiimide compound, it is preferable to mix | blend 0.1-5 mass parts with respect to 100 mass parts of this flame-retardant PEs resin composition. By mix | blending a carbodiimide compound in this range, the outstanding hydrolysis resistance can be provided, without reducing heat resistance.
From this viewpoint, the amount of the carbodiimide compound is more preferably 0.5% by mass or more, particularly preferably 1% by mass or more, with respect to 100 parts by mass of the flame retardant PEs resin composition. Moreover, it is more preferable that it is 4 mass% or less, and it is preferable that it is 3 mass% or less especially.

  The flame retardant PEs resin composition may contain additives such as a heat stabilizer, an antioxidant, a UV absorber, a plasticizer, a nucleating agent, a light stabilizer, a pigment, and a dye as necessary. .

<Physical characteristics of the flame retardant PEs resin composition>
This flame-retardant PEs resin composition can be prepared to have flame retardancy, flexibility, mechanical properties and heat resistance.
More specifically, regarding the flame retardancy, flame retardancy satisfying the VTM-0 standard can be obtained in the UL94 vertical combustion test defined by Underwriters Laboratories.
Regarding the mechanical properties, when the tensile strength at break is measured based on JIS C 2318, the tensile strength can be adjusted to 10 MPa or more, preferably 15 MPa or more.
Regarding the flexibility, when the tensile elongation at break is measured according to JIS C 2318, the tensile elongation can be adjusted to 10% or more, preferably 20% or more.
Regarding heat resistance, when the crystal melting heat quantity ΔHm is measured based on JIS K7121, the crystal melting heat quantity (ΔHm) can be adjusted to 1 J / g or more, preferably 3 J / g or more.

<Uses of the present flame-retardant PEs resin composition>
The flame retardant PEs resin composition can be formed into a film, a sheet, a plate, an injection molded product, or the like.
Specifically, raw materials such as polyester resin (A) and melamine, and other resins and additives such as polyester resin (B) are directly mixed and put into an extruder or injection molding machine. A method of forming, or melting and mixing the raw materials using a twin-screw extruder, extruding into a strand shape to create pellets, and then putting the pellets into an extruder or injection molding machine to form a method Can do. In any method, it is necessary to consider a decrease in molecular weight due to hydrolysis of the polyester-based resin, and the latter is preferably selected for uniform mixing. Therefore, the latter manufacturing method will be described below.

Polyester resin (A) and melamine, and if necessary, other resins and additives such as polyester resin (B) are sufficiently dried to remove moisture, and then melt mixed using a twin-screw extruder, Extrude into strand shape to make pellets.
At this time, in consideration of the composition ratio of the polyester resins (A) and (B), for example, the melting point changes depending on the content ratio of terephthalic acid, and the viscosity changes depending on the blending ratio of each raw material, It is preferable to select the temperature appropriately. In consideration of the sublimation temperature of melamine, the molding temperature is preferably adjusted to a temperature range of 160 ° C. or higher and 220 ° C. or lower, particularly less than 210 ° C.

  After the pellets produced by the above method are sufficiently dried to remove moisture, a film, a sheet, a plate, or an injection molded product can be molded by the following method.

  As film, sheet and plate molding methods, roll stretching, tenter stretching, tubular and inflation methods, as well as sheet and plate molding methods such as general T-die casting and pressing can be adopted. it can.

The molding method of the injection molded body is not particularly limited, and for example, an injection molding method such as a general injection molding method for a thermoplastic resin, a gas assist molding method, and an injection compression molding method can be employed.
In addition to the above methods, an in-mold molding method, a gas press molding method, a two-color molding method, a sandwich molding method, PUSH-PULL, SCORIM, or the like can also be employed according to other purposes.

Moreover, the laminated body can also be formed by providing one or more layers not containing a flame retardant on one side or both sides of the layer made of the flame retardant PEs resin composition.
At this time, the layer containing no flame retardant is not particularly limited. For example, in the case of imparting heat resistance, mechanical properties, and surface properties, a layer made of the stretched polyethylene terephthalate film or the like is formed. Is preferred. For the purpose of improving adhesiveness with other materials and using for adhesive tapes, etc., adhesive layer made of rubber, acrylic, vinyl ether or other solvent type or emulsion type adhesives Is preferably formed.
Under the present circumstances, it is preferable that the ratio of the thickness of the layer which consists of a flame-retardant polyester-type resin composition which occupies for the total thickness of a laminated body shall be 20-95%. By setting the thickness ratio of the flame-retardant polyester resin composition within such a range, it is possible to provide a laminate that does not impair flame retardancy and mechanical properties. From this viewpoint, the ratio of the thickness of the layer composed of the flame-retardant polyester resin composition in the total thickness of the laminate is particularly preferably 30% or more, and particularly preferably 40% or more, and 80%. It is particularly preferable that the ratio is 70% or less.

  As a method of laminating the layer composed of the present flame retardant PEs resin composition and the layer not containing a flame retardant, the layers can be laminated by coextrusion, extrusion lamination, thermal lamination, dry lamination, or the like.

  In the case of co-extrusion, a laminate is formed by joining a plurality of layers through a feed block or a multi-manifold die using a plurality of extruders. In order to further impart heat resistance and mechanical strength to the laminate, the laminate obtained in the above step can be stretched uniaxially or biaxially using a roll method, a tenter method, a tubular method, or the like. .

  In the case of extrusion lamination, a layer made of a polyester resin (A) is extruded from a T die, I die, etc. using a single screw or twin screw extruder, and then a roll method, a tenter method, a tubular method, etc. To obtain a monolayer. Subsequently, a laminate can be obtained by laminating a layer containing no flame retardant on one side or both sides of the obtained layer.

  In the case of thermal lamination and dry lamination, a layer made of the polyester resin (A) is extruded from a T die, an I die or the like using a single screw or twin screw extruder to obtain a single layer body. Moreover, the layer which does not contain a flame retardant is produced using the same method. Subsequently, these layers are laminated by heating or by disposing an adhesive layer between the layers, whereby a laminate can be obtained.

  Since this flame-retardant PEs resin composition has excellent flame retardancy, mechanical properties, flexibility and heat resistance, it can be used for cellular phone parts, cable coating materials, packings, electrical insulation films and sheets, flat cables. It can be widely used in home appliance applications such as construction materials and vibration damping materials, and in fields such as adhesive tape base materials, rolls, water shielding sheets, gaskets, anti-slip materials, and wire covering materials. In addition, since it does not contain a halogen compound or a phosphorus compound, it is possible to provide a material with excellent safety that does not cause problems such as environmental pollution.

<Explanation of terms>
In the present invention, the expression “main component” includes the meaning of allowing other components to be contained within a range that does not hinder the function of the main component unless otherwise specified. Although the content ratio of the main component is not particularly specified, its component (when two or more components are main components, the total amount thereof) is 60% by mass or more, particularly 70% by mass or more in the composition. Of these, 90% by mass or more (including 100%) is preferable. For example, the mixture in the resin composition a preferably occupies 60% by mass or more, particularly 70% by mass or more, particularly 90% by mass or more (including 100%) in the resin composition a.

Further, in this specification, when “X to Y” (X and Y are arbitrary numbers) is described, it means “X or more and Y or less” unless otherwise specified, or “preferably larger than X” or The meaning of “preferably smaller than Y” is included.
In addition, when “X or more” (X is an arbitrary number) or “Y or less” (Y is an arbitrary number), it is “preferably greater than X” or “preferably less than Y”. Includes intentions.

  In general, "film" refers to a thin flat product that is extremely small compared to its length and width and whose maximum thickness is arbitrarily limited, usually supplied in the form of a roll. (Japanese Industrial Standards JISK6900), “sheet” generally refers to a product that is thin by definition in JIS and whose thickness is small and flat instead of length and width. However, since the boundary between the sheet and the film is not clear and it is not necessary to distinguish the two in terms of the present invention, in the present invention, even when the term “film” is used, it includes “sheet” and is referred to as “sheet”. In some cases, “film” is included.

  Examples are shown below, but the present invention is not limited by these. In addition, the result shown in an Example evaluated by the following method.

(1) Flame retardance When the thickness is 200 μm or less, an evaluation sample having a length of 200 mm × width 50 mm, and when the thickness exceeds 200 μm, the length is 127 mm × width 13 mm (thickness varies depending on each test piece). Test using the sample for evaluation based on the procedures of Underwriters Laboratories Safety Standard UL94 Thin Material Vertical Combustion Test (when the sample thickness is 200 μm or less) and UL94 Vertical Combustion Test (when the sample thickness exceeds 200 μm) A combustion test was carried out at 5 times, and the state of combustion (particularly, the presence or absence of dripping material during combustion) was observed and the combustion time (total combustion time of 5 tests) was measured.
In the UL94 vertical combustion test, samples with a thickness of 200 μm or less are judged on the basis of the UL94VTM criteria whether or not the VTM-0, 1 and 2 standards are satisfied. A product satisfying VTM-0 was evaluated as an acceptable product. For samples with a thickness exceeding 200 μm, whether or not the standards of VTM-0, 1, and 2 are satisfied is judged based on the UL94V criteria, and those that do not satisfy VTM-2 are evaluated as non-standard. Those satisfying −0 were evaluated as acceptable products.

(2) Tensile strength and tensile elongation Using an evaluation sample having a length of 200 mm and a width of 20 mm, the tensile break strength and the tensile break elongation were measured based on JIS C 2318. The strength and elongation at break were measured, and the average value at n = 5 was determined. Measurements were performed at an ambient temperature of 23 ° C., a relative humidity of 50%, a pulling speed of 200 mm / min, and a gripping interval of 100 mm, and the strength and elongation at break were measured, and the average value at n = 5 was obtained.
A tensile strength of 10 MPa or more and a tensile elongation of 10% or more were evaluated as acceptable.

(3) Heat of crystal melting (ΔHm)
Based on JIS K7121, about the sample cut out to about 10 mg, crystal melting calorie | heat amount (DELTA) Hm of polyester-type resin was measured using DSC-7 by Perkin Elmer. The measurement procedure is shown below.

a. The temperature was raised from 30 ° C. to 200 ° C. at a rate of 500 ° C./min, and then held at 200 ° C. for 2 minutes.
b. Next, the temperature drop was measured from 200 ° C. to 30 ° C. at a rate of 10 ° C./min.
c. Furthermore, the temperature rise measurement was performed from 30 ° C. to 200 ° C. at a rate of 10 ° C./min.

  The heat of crystal melting (ΔHm) was read from the thermogram obtained in the process of c.

(4) Heat resistance One end of an evaluation sample having a length of 200 mm and a width of 20 mm is fixed and held vertically in a baking test apparatus (DKS-5S manufactured by Daiei Kagaku Seiki Seisakusho) at 140 ° C. for 1 hour. Heated. The appearance of the sample after heating was visually observed. A sample having no significant change compared to that before heating was marked with ◯, and a sample showing shrinkage, wrinkles, significant deformation, etc. compared with before heating was marked with ×.

<Raw material>
Next, the raw materials used in Examples and Comparative Examples, that is, polyester resin (A), polyester resin (B), and melamine will be described.

[Polyester resin (A) -1]
Product name: Byron Byron GM-443 manufactured by Toyobo Co., Ltd.
Composition: polyvalent carboxylic acid component = terephthalic acid 53 mol%, isophthalic acid 38 mol%, adipic acid 9 mol%, polyhydric alcohol component = 1,4-butanediol 100 mol%
Physical property values: mass average molecular weight = 47,000, Tg = 26 ° C., Tm = 145 ° C., ΔHm = 22.8 J / g

[Polyester resin (A) -2]
Product name: Byron GA-1300 manufactured by Toyobo Co., Ltd.
Composition: polycarboxylic acid component = terephthalic acid 66 mol%, isophthalic acid 10 mol%, adipic acid 24 mol%, polyhydric alcohol component = 1,4-butanediol 100 mol%
Physical property values: mass average molecular weight = 50,000, Tg = −6 ° C., Tm = 167 ° C., ΔHm = 23.7 J / g

[Polyester resin (A) -3]
Product name: Byron GA-1310 manufactured by Toyobo Co., Ltd.
Composition: polyhydric carboxylic acid component = terephthalic acid 71 mol%, isophthalic acid 29 mol%, polyhydric alcohol component = 1,4-butanediol = 100 mol%
Physical property values: mass average molecular weight = 56,000, Tg = 27 ° C., Tm = 179 ° C., ΔHm = 24.5 J / g

[Polyester resin (B) -1]
Product name: Byron 30P manufactured by Toyobo Co., Ltd.
Composition: polyhydric carboxylic acid component = terephthalic acid 54 mol%, sebacic acid 46 mol%, polyhydric alcohol component = 1,4-butanediol 82 mol%, ethylene glycol = 18 mol%
Physical property values: mass average molecular weight = 96,000, Tg = −28 ° C., Tm = 125 ° C., ΔHm = 2.0 J / g

[Polyester resin (B) -2]
Product name: Byron Byron GM-913 manufactured by Toyobo Co., Ltd.
Composition: polycarboxylic acid component = terephthalic acid 66 mol%, isophthalic acid 34 mol%, polyhydric alcohol component = 1,4-butanediol 82 mol%, polytetramethylene ether glycol 18 mol%
Physical property values: mass average molecular weight = 100,000, Tg = −70 ° C., Tm = 126 ° C., ΔHm = 10.2 J / g

[melamine]
Fine melamine produced by Nissan Chemical Industries (average particle size 5μm, no surface treatment)

Example 1
The polyester resin (A) -1 and fine melamine were dry blended at a mixing mass ratio of 80:20, kneaded at 200 ° C. using a 40 mmφ co-directional twin screw extruder, extruded from a T die, and then about The sheet was rapidly cooled with a 40 ° C. casting roll to prepare a sheet having a thickness of 100 μm. The obtained sheet was evaluated for flame retardancy, tensile strength, tensile elongation, and heat resistance. The results are shown in Table 1.

(Example 2)
A sheet having a thickness of 100 μm was prepared in the same manner as in Example 1 except that the mixing mass ratio of the polyester resin (A) -1 and fine melamine was set to 70:30. Table 1 shows the results of the same evaluation as in Example 1 for the obtained sheet.

(Example 3)
A sheet having a thickness of 100 μm was produced in the same manner as in Example 1 except that the mixing mass ratio of the polyester resin (A) -1 and fine melamine was set to 50:50. Table 1 shows the results of the same evaluation as in Example 1 for the obtained sheet.

Example 4
After blending the polyester resin (A) -2 and fine melamine at a mixing mass ratio of 70:30, a sheet having a thickness of 100 μm was produced in the same manner as in Example 1. Table 1 shows the results of the same evaluation as in Example 1 for the obtained sheet.

(Example 5)
After blending the polyester resin (A) -3 and fine melamine at a mixing mass ratio of 70:30, a sheet having a thickness of 100 μm was produced in the same manner as in Example 1. Table 1 shows the results of the same evaluation as in Example 1 for the obtained sheet.

(Example 6)
After blending polyester resin (A) -2, polyester resin (B) -1 and fine melamine at a mixing mass ratio of 50:20:30, a sheet having a thickness of 100 μm is produced in the same manner as in Example 1. did. Table 1 shows the results of the same evaluation as in Example 1 for the obtained sheet.

(Example 7)
After blending polyester resin (A) -2, polyester resin (B) -1 and fine melamine at a mixing mass ratio of 40:30:30, a sheet having a thickness of 100 μm is produced in the same manner as in Example 1. did. Table 1 shows the results of the same evaluation as in Example 1 for the obtained sheet.

(Example 8)
After blending polyester resin (A) -2, polyester resin (B) -1, and fine melamine at a mixing mass ratio of 30:40:30, a sheet having a thickness of 100 μm is produced in the same manner as in Example 1. did. Table 1 shows the results of the same evaluation as in Example 1 for the obtained sheet.

Example 9
After blending polyester resin (A) -2, polyester resin (B) -2, and finely divided melamine in a mixing mass ratio of 40:30:30, a sheet having a thickness of 100 μm is produced in the same manner as in Example 1. did. Table 1 shows the results of the same evaluation as in Example 1 for the obtained sheet.

(Comparative Example 1)
After blending the polyester resin (A) -1 and fine melamine at a mixing mass ratio of 90:10, a sheet having a thickness of 100 μm was produced in the same manner as in Example 1. Table 1 shows the results of the same evaluation as in Example 1 for the obtained sheet.

(Comparative Example 2)
After blending polyester-based resin (A) -1 and fine melamine at a mixing mass ratio of 30:70, a sheet having a thickness of 100 μm was produced in the same manner as in Example 1. Table 1 shows the results of the same evaluation as in Example 1 for the obtained sheet.

(Comparative Example 3)
After blending polyester resin (B) -2 and fine melamine at a mixing mass ratio of 70:30, a sheet having a thickness of 100 μm was produced in the same manner as in Example 1. Table 1 shows the results of the same evaluation as in Example 1 for the obtained sheet.

(Comparative Example 4)
Example: After blending polyester resin (A) -1 and PHOSMEL-200 at a mixing mass ratio of 70:30, using PHOSMEL-200 (melamine polyphosphate) manufactured by Nissan Chemical Industries, Ltd. instead of melamine A sheet having a thickness of 100 μm was produced in the same manner as in Example 1. Table 1 shows the results of the same evaluation as in Example 1 for the obtained sheet.

(Comparative Example 5)
Example: After blending polyester resin (A) -1 and MC-860 at a mixing mass ratio of 70:30 using MC-860 (melamine cyanurate) manufactured by Nissan Chemical Industries, Ltd. instead of melamine A sheet having a thickness of 100 μm was produced in the same manner as in Example 1. Table 1 shows the results of the same evaluation as in Example 1 for the obtained sheet.

(Discussion)
Flame retardant polyester resin composition obtained by mixing polyester resin (A) having a glass transition temperature Tg of -20 ° C to 40 ° C and a crystal melting temperature Tm of 140 ° C to 190 ° C, and melamine. The flame retardant polyester-based resin composition having a melamine ratio of 20 to 60% by mass can obtain a pass evaluation for any of flame retardancy, tensile strength, tensile elongation, and heat resistance. I understood that I could do it.

In addition, melamine can be made flame retardant by blending it with polyester resin (A), whereas melamine derivatives such as melamine cyanurate and melamine polyphosphate are specific polyester resins (A). The result that can not be flame retardant.
Melamine is generally difficult to use as a flame retardant, but it has been found that it can be used as a flame retardant for certain polyester resins.
It turned out that it is preferable that the ratio of a melamine is 20-60 mass% of a flame-retardant polyester-type resin composition.

  Further, a polyester resin (B) having a glass transition temperature Tg of −100 ° C. or more and less than −20 ° C. and a crystal melting temperature Tm of 100 ° C. or more and less than 140 ° C. is converted into a polyester resin (A) and a polyester resin. By blending the resin (B) so as to have a mass ratio of 90:10 to 30:70, all of flame retardancy, tensile strength, tensile elongation, and heat resistance can be evaluated as acceptable. In addition, it has been found that the tensile elongation can be particularly increased.

Claims (4)

A flame retardant polyester resin composition containing a mixture of a polyester resin (A) having a glass transition temperature Tg of −20 ° C. to 40 ° C. and a crystal melting temperature Tm of 140 ° C. to 190 ° C. and melamine. There,
The flame-retardant polyester resin composition, wherein the ratio of melamine in the flame-retardant polyester resin composition is 20 to 60% by mass. The glass transition temperature Tg is −20 ° C. to 40 ° C., the crystal melting temperature Tm is 140 ° C. to 190 ° C., and the glass transition temperature Tg is −100 ° C. or more and less than −20 ° C. A flame-retardant polyester resin composition containing a mixture of a polyester resin (B) having a crystal melting temperature Tm of 100 ° C. or higher and lower than 140 ° C. and melamine,
The ratio of melamine in the flame retardant polyester resin composition is 20 to 60% by mass, and the mass ratio of the polyester resin (A) and the polyester resin (B) is 90:10 to 30:70. A flame-retardant polyester-based resin composition characterized by being.   The polyester resin (A) or the polyester resin (B), or both of these resins, and at least one polycarboxylic acid component selected from terephthalic acid, isophthalic acid, and adipic acid; The flame retardant polyester resin composition according to claim 1 or 2, which is a copolymer comprising at least one polyhydric alcohol component selected from -butanediol and ethylene glycol.   The flame retardant polyester resin composition according to any one of claims 1 to 3, wherein an average particle size of melamine is 10 µm or less.