JPH06172621A - Polyester resin composition - Google Patents

Abstract

PURPOSE:To obtain the subject composition, having a low combustion calorific value, excellent in thermal stability arid useful as a sheet, etc., for food containers and a material for molding processing by blending an aliphatic polyester synthesized from a glycol and an aliphatic dibasic acid with a filter. CONSTITUTION:The objective composition is obtained by including (B) 10-70wt.% (preferably 20-60wt.%) filler (preferably a metallic oxide, hydroxide, etc.) in (A) an aliphatic polyester, synthesized from a glycol (e.g. ethylene glycol) and an aliphatic dibasic acid and/or an acid derivative (e.g. succinic acid) (preferably a saturated aliphatic polyester having >=10000 molecular weight and >=60 deg.C melting point). Furthermore, a small amount of other components, e.g. a polyhydric alcohol is preferably used in combination therewith.

Description

Detailed Description of the Invention

[0001]

The present invention has a number average molecular weight of 10,
Fats that have a practically sufficient high molecular weight of 000 or more and a filler are blended and have a small calorific value when burned, have microbial degradability, and have excellent thermal stability and mechanical strength. The present invention relates to a group polyester resin composition, a sheet obtained by processing the same, and a secondary processed product thereof.

[0002]

2. Description of the Related Art High molecular weight polyesters (hereinafter referred to as
The high molecular weight polyester referred to herein means a number average molecular weight of 20,000 or more. It is no exaggeration to say that) is limited to polyethylene terephthalate, which is a condensate of terephthalic acid (including dimethyl terephthalate) and ethylene glycol, or polybutylene terephthalate from terephthalic acid and butylene glycol.

Although there is an example in which 2,6-naphthalenedicarboxylic acid is used instead of terephthalic acid, a polyester in which an aliphatic dicarboxylic acid is used as a dicarboxylic acid is molded into a sheet, a film, a fiber or the like and put into practical use. There can be no examples.

One of the reasons why it has not been put to practical use is that, even if it is crystalline, the melting point of the aliphatic polyester is almost 100 ° C. or less, and moreover, the thermal stability upon melting is poor. , And more importantly, the properties of the aliphatic polyester, especially the mechanical properties represented by the tensile strength, are extremely low, and even at the same level of the number average molecular weight as polyethylene terephthalate, it shows only a significantly inferior value, and no practicality is found. It was nothing else.

[0005] Researches for increasing the number average molecular weight of aliphatic polyesters to improve their physical properties seem to have not progressed satisfactorily due to their poor thermal stability.

[0006] Polyesters such as polyethylene terephthalate, which are generally used in large quantities in the field of packaging containers and industrial materials at present, are not biodegradable, so that they are not decomposed forever by simply discarding them after use, and they remain in rivers. However, it has problems such as incineration for complete treatment because it pollutes the ocean and soil. But,
Although its calorific value is as low as 5,500 to 6,000 kcal / kg compared to polyethylene and polypropylene, the calorific value is still large compared to the average value of the calorific value of municipal waste, causing a large amount of wear in the incinerator. There is also.

[0007]

DISCLOSURE OF THE INVENTION The present invention has a practically sufficient high molecular weight, excellent thermal stability and mechanical properties typified by tensile strength, and generates heat by combustion even if it is discarded after use. Provided are an aliphatic polyester resin composition which has a small amount, can be decomposed by microorganisms, etc., is easy to dispose, and has a heat-sealing property as it is, a sheet produced from the same, and a secondary molded article thereof. The purpose is to

[0008]

According to the present invention, a filler is blended with an aliphatic polyester having a number average molecular weight of at least 10,000, which is mainly synthesized from glycol and an aliphatic dibasic acid or an acid derivative thereof. The above object was achieved by developing a low combustion calorific value aliphatic polyester resin composition characterized by:

The low combustion calorific value aliphatic polyester resin composition has excellent mechanical properties when formed into a sheet. Further, such a sheet is subjected to heat forming such as vacuum forming and pressure forming. They have completed the present invention by finding that they have properties extremely suitable for moldings or parts.

The aliphatic polyester referred to in the present invention is mainly composed of a polyester synthesized mainly from glycols and an aliphatic dibasic acid or an acid anhydride thereof, and has a sufficiently high molecular weight. This is a product in which a relatively high molecular weight polyester prepolymer having hydroxyl groups at both ends is synthesized and then these prepolymers are further coupled by a coupling agent.

Conventionally, a low molecular weight polyester prepolymer having a hydroxyl group as a terminal group and a number average molecular weight of 2,000 to 2,500 is reacted with a diisocyanate to form a polyurethane, which is used as a rubber, foam, paint or adhesive. It is widely used as an agent.

However, the polyester prepolymers used in these polyurethane type foams, paints and adhesives are low molecular weight prepolymers having a number average molecular weight of 2,000 to 2,500. The amount of diisocyanate used must be 10 to 20 parts by weight in order to obtain the practical physical properties of polyurethane based on 100 parts by weight of the low molecular weight prepolymer. When such a large amount of diisocyanate is added to the melted low molecular weight polyester at 150 ° C. or higher, gelation occurs and a melt-moldable resin cannot be obtained.

Further, as in the case of polyurethane rubber,
A method of adding a diisocyanate to convert a hydroxyl group to an isocyanate group and further increasing the number average molecular weight with glycol can be considered, but the amount of the diisocyanate used is as described above. 10 parts by weight or more is necessary with respect to parts by weight. At this time, if a heavy metal-based catalyst is used for the synthesis of polyester, the reactivity of the isocyanate group is remarkably promoted, resulting in poor storage stability, crosslinking reaction, and branch formation. Therefore, the polyester prepolymer is synthesized without a catalyst. Therefore, even if the number average molecular weight is high, the limit is about 2,500.

In the polyester prepolymer for obtaining the aliphatic polyester used in the present invention, the terminal group obtained by reacting glycol with an aliphatic dibasic acid or an anhydride thereof is substantially a hydroxyl group, It is a saturated aliphatic polyester having an average molecular weight of 5,000 or more, preferably 10,000 or more, a relatively high molecular weight, and a melting point of 60 ° C. or more.

When the number average molecular weight is less than 5,000, for example, about 2,500, a polyester having good physical properties cannot be obtained even with a small amount of the coupling agent of 0.1 to 5 parts by weight. Number average molecular weight is 5,000
A polyester prepolymer of 0 or more can synthesize a high molecular weight polyester by using a small amount of a coupling agent without forming a gel during the reaction even under severe conditions such as a molten state.

Examples of glycols used include ethylene glycol, butanediol 1,4, hexanediol 1,6, decamethylene glycol, neopentyl glycol and 1,4-cyclohexanedimethanol. Ethylene oxide can also be utilized. You may use these glycols together.

Aliphatic dibasic acids or their acid derivatives which react with glycols to form aliphatic polyesters include succinic acid, adipic acid, suberic acid, sebacic acid,
There are dodecanoic acid, succinic anhydride, adipic anhydride, and lower alcohol esters such as dimethyl ester, which are commercially available and can be used in the present invention. You may use together polybasic acid or its acid anhydride. These compounds may be previously made into low molecular weight esters and polymerized by a deglycol reaction.

These glycols and dibasic acids are mainly aliphatic, but a small amount of other components such as a trifunctional or tetrafunctional polyhydric alcohol, oxycarboxylic acid and polycarboxylic acid may be used in combination. preferable.

Typical examples of the trifunctional polyhydric alcohol component are trimethylolpropane, glycerin and their anhydrides, and typical examples of the tetrafunctional polyhydric alcohol component are pentaerythritol.

As the trifunctional oxycarboxylic acid, malic acid is practically advantageous, and as the tetrafunctional oxycarboxylic acid component, citric acid is practical because commercial products can be easily obtained at low cost.

As the trifunctional polyvalent carboxylic acid (or its acid anhydride) component, for example, trimesic acid, propanetricarboxylic acid and the like can be used, but trimellitic anhydride is advantageous in practical use.

Examples of the tetrafunctional polyvalent carboxylic acid (or acid anhydride thereof) include pyromellitic dianhydride, benzophenonetetracarboxylic acid anhydride, cyclopentanetetracarboxylic acid anhydride and the like.

The polyfunctional component is used in such a proportion that the glycol component, the aliphatic (including cycloaliphatic) component, or the dicarboxylic acid (or its acid anhydride) component is 10 in the number of moles.
In the case of a trifunctional component, 5 mol% or less with respect to 0 mol%,
It is preferably 0.5 mol% or more and 3 mol% or less, and in the case of a tetrafunctional component, 3 mol% or less, preferably 0.2 mol%
It is 2 mol% or less.

If the proportion of the trifunctional component used exceeds 5 mol%, or if the proportion of the tetrafunctional component exceeds 3 mol%, the risk of gelation during the esterification reaction increases significantly.

The polyester prepolymer for an aliphatic polyester used in the present invention has a terminal group substantially a hydroxyl group. For that purpose, glycols and dibasic acid (or its acid anhydride) used in the synthesis reaction are used. The use ratio of is required to use some excess of glycols.

The synthesis of relatively high molecular weight polyester prepolymers requires the use of a deglycolization reaction catalyst during the deglycolization reaction following esterification.

Examples of the deglycolization catalyst include titanium compounds such as acetoacetoyl type titanium chelate compounds and organic alkoxy titanium compounds.
These titanium compounds can be used in combination. Examples of these include diacetoacetoxyoxytitanium ("Narsem titanium" manufactured by Nippon Kagaku Sangyo Co., Ltd.), tetraethoxytitanium, tetrapropoxytitanium, tetrabutoxytitanium and the like. The titanium compound is used in an amount of 0.001 to 100 parts by weight of the polyester prepolymer.
It is 1 part by weight, preferably 0.01 to 0.1 part by weight.
The titanium compound may be added from the beginning of esterification or immediately before the deglycolization reaction.

As a result, the polyester prepolymer usually has a number average molecular weight of 5,000 or more, preferably 20,000.
It is more preferable that those having a melting point of 0 ° C. or higher and a melting point of 60 ° C. or higher can be easily obtained and have crystallinity.

To obtain the aliphatic polyester of the present invention, the number average molecular weight is more than 5,000, preferably 1.
Coupling agents are used to further increase the number average molecular weight of polyester prepolymers having 50,000 or more end groups which are substantially hydroxyl groups.

Examples of the coupling agent include diisocyanate, oxazoline, diepoxy compound, acid anhydride and the like, and diisocyanate is particularly preferable.

In the case of an oxazoline or diepoxy compound, it is necessary to react the hydroxyl group with an acid anhydride or the like to convert the terminal into a carboxyl group before using the coupling agent.

The diisocyanate is not particularly limited,
For example, the following types are listed. 2,4-tolylene diisocyanate, 2,4-tolylene diisocyanate and 2,
Mixture with 6-tolylene diisocyanate, diphenylmethane diisocyanate, 1,5-naphthylene diisocyanate, xylylene diisocyanate, hydrogenated xylylene diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, especially hexa Methylene diisocyanate is preferable from the viewpoint of the hue of the resin produced, the reactivity when the polyester is added, and the like.

The amount of these coupling agents added is 0.1 to 5 parts by weight, preferably 0.5 to 3 parts by weight, based on 100 parts by weight of the polyester prepolymer.

If it is less than 0.1 part by weight, the coupling reaction is insufficient, and if it exceeds 5 parts by weight, gelation occurs.

The addition is preferably carried out under the condition that the polyester prepolymer is in a uniform molten state and can be easily stirred. It is not impossible to add it to a solid polyester prepolymer and melt and mix it through an extruder, but add it to an aliphatic polyester production device or to a molten polyester prepolymer (for example, in a kneader). Is practical.

In this case, the aliphatic polyester has a number average molecular weight of 10,000 or more, which makes the polyester resin and the polyester resin composition have sufficient mechanical properties.

The filler used in the present invention is generally widely used in the fields of synthetic resin and rubber.
As these fillers, inorganic compounds or metals that do not react with oxygen and water and those that do not decompose during kneading and molding are preferably used. As the filler, oxides of metals such as aluminum, copper, iron, lead, nickel, magnesium, calcium, barium, zinc, zirconium, molybdenum, silicon, antimony and titanium,
Compounds such as hydrates (hydroxides), sulfates, carbonates, and silicates, double salts thereof, mixtures thereof, carbon fibers, and the like can be given. A typical example of the filler is Japanese Patent Application No.
9-124481.

Of these fillers, the powdery ones preferably have a diameter of 30 μm or less (preferably 10 μm or less). The diameter is 1 to 100 μm for fibrous materials
(Preferably 1 to 80 μm) and the length is 0.1 to 10
mm (preferably 0.1 to 5.0 mm) is desirable. Furthermore, the flat plate type has a thickness of 30 μm or less (preferably 10 μm
m or less) is preferable. Among these fillers, flat plate-shaped (flake-shaped) and powdered ones are particularly preferable.

The composition ratio (content ratio) of the inorganic filler in the polyester resin composition is 10 to 70% by weight, preferably 15 to 65% by weight, more preferably 20 to 60% by weight.
Weight percent is preferred. When the composition ratio of the inorganic filler in the inorganic filler-containing polyester resin composition exceeds 70% by weight, the impact resistance of the obtained sheet and container is significantly reduced, and only a sheet or container which is not suitable for practical use can be obtained. . On the other hand, if it is less than 10% by weight, the calorific value of combustion is 5,000.
It does not fall below 0 kcal / kg, and neither rigidity nor heat resistance is improved.

The aliphatic polyester resin composition thus obtained has a temperature of 190 ° C. and a shear rate of 100 (sec).
^-1 ) has a melt viscosity of 1.0 × 10 ^{3 to} 1.0 × 10
⁶ poise. Particularly preferably 1.0 × 10 ^{4 to} 5.
It is 0 × 10 ⁴ poise. If it is less than 5,000 poise, it is easy to process, but mechanical properties such as heat resistance (especially thermal stability of the sheet), impact resistance, and elongation at break are deteriorated.
On the other hand, if it exceeds 10 ⁶ poise, extrudability is deteriorated due to heat generation or the like, and a high quality sheet cannot be obtained.

The melt viscosity was measured with a nozzle diameter of 1.0.
mm, using a nozzle of L / D = 10, resin temperature 1
Shear rate 100 sec from the relational graph between shear rate and apparent viscosity measured by capillary rheometer at 90 ° C
The viscosity at ^-1 was determined.

The purpose of producing the polyester resin composition of the present invention can be achieved by uniformly mixing the polyester resin and the filler in a desired ratio.
As a mixing method, there is a method of kneading in a molten state using a mixer such as an extruder, a mixing roll, a kneader, a roll mill, a Banbury mixer, and a continuous mixer which are usually used in the field of olefin polymers. Alternatively, a masterbatch (mixture) obtained by producing a high-concentration filler masterbatch such as polyester resin
And polyester resin may be mixed.

The polyester resin composition thus obtained may be used as it is, but depending on the purpose of use, it is generally used in the field of olefin polymers for oxygen, light (ultraviolet rays) and heat. The above-mentioned characteristics that the polyester resin composition of the present invention has additives such as a stabilizer, a flame retardant, a lubricant, a processability improver, a colorant, an antistatic agent, an electrical property improver or an adhesion improver ( You may add in the range which does not impair the effect.

The aliphatic polyester resin composition according to the present invention is formed into a sheet by various molding methods such as calendering method and T-die method. The resin temperature in this case is 100 to 2
The temperature is 70 ° C, preferably 100 to 250 ° C. 100 ° C
If it is less than 270, the viscosity is too high and it is difficult to form a sheet.
If the temperature exceeds ℃, the resin deteriorates, which is inconvenient.

The calorific value of combustion 5,000 obtained by the present invention
The aliphatic polyester composition of 0 kcal / kg or less is
It can improve heat resistance and rigidity and can be used as a packaging material or a plastic sheet for general use. Further, since the sheet is suitable for vacuum forming and pressure forming, it is suitable as a material for molded articles such as containers and parts by such secondary thermoforming.

[0046]

EXAMPLES The present invention will be described below with reference to examples and comparative examples. The biodegradability is 10 cm x 20 cm, and each sheet is sandwiched between stainless steel molds equipped with a polyethylene net at the window to bury it in deep soil of 10 cm, and it is dug out after 12 months, and its degradability is evaluated. did. In addition, a commercially available paperboard having the same thickness was compared. The evaluation of the following state A is preferable. State A: When the aliphatic polyester sheet is more decomposed than the paper and is in a tattered state with perforation of the sheet. State B: When the decomposition of the paper is more advanced than the aliphatic polyester sheet and the aliphatic polyester sheet is still firm.

The tensile properties were measured according to JIS K7113 and the calorific value of combustion was measured according to the calorimeter method of JIS M8814. The rigidity was measured in both directions MD and TD with an Olsen stiffness meter (ASTM D747), and the lower value was used as the measured value. The dirt impact impact strength was measured by ASTM D1709.

Example 1 A 700 L reactor was purged with nitrogen, and then 183 kg of 1,4-butanediol and 224 kg of succinic acid were charged. The temperature was raised in a nitrogen stream, and the esterification reaction by dehydration condensation was carried out for 3.5 hours at 192 to 220 ° C. for 3.5 hours, and then nitrogen was stopped for 3.5 hours under a reduced pressure of 20 to 2 mmHg. The sample collected had an acid value of 9.2 mg / g, a number average molecular weight (Mn) of 5,160, and a weight average molecular weight (Mw) of 10,67.
It was 0. Subsequently, 34 g of tetraisopropoxytitanium as a catalyst was added under a nitrogen stream under normal pressure. Raise the temperature to 15 ~ 0.2mmHg at 215 ~ 220 ℃
The deglycolization reaction was performed for 5.5 hours under reduced pressure. The sample collected had a number average molecular weight (Mn) of 16,800 and a weight average molecular weight (Mw) of 43,600. The yield of this polyester (A1) is 339 when condensed water is removed.
It was kg.

5420 g of hexamethylene diisocyanate was added to a reactor containing 339 kg of polyester (A1), and a coupling reaction was carried out at 180 to 200 ° C. for 1 hour. The viscosity increased rapidly but no gelation occurred. Next, 1700 g of Irganox 1010 (manufactured by Ciba Geigy) as an antioxidant and 1700 g of calcium stearate as a lubricant were added, and stirring was continued for another 30 minutes. This reaction product was extruded into water with an extruder and cut into pellets with a cutter. 90 ° C
The yield of polyester (B1) after vacuum drying for 6 hours was 300 kg.

The obtained polyester (B1) is a slightly ivory white waxy crystal and has a melting point of 110.
C., the number average molecular weight (Mn) is 35,500, the weight average molecular weight (Mw) is 170,000, the MFR (190 ° C.) is 1.0 g / 10 minutes, the viscosity of a 10% solution of orthochlorophenol is 230 poises, Temperature 190 ℃, shear rate 10
The melt viscosity at ⁰ sec ⁻¹ was 1.5 × 10 ⁴ poise. The average molecular weight is measured by Shodex GPC.
System-11, the solvent is a solution of CF ₃ COONa in 5 mmol hexafluoroisopropyl alcohol, the concentration is 0.1% by weight, and the calibration curve is Showa Denko KK's PMMA standard sample Shodex Standard M-75.
I went there.

Next, 70 wt% of this polyester resin,
After blending a mixture with 30 wt% of talc having an average particle size of 5.0 μm with a Henschel mixer, screw diameter 50 m /
Using a m-direction twin-screw extruder, kneading and pelletizing was performed at a resin temperature of 180 ° C. This composition had a melt viscosity of 2.3 × 10 ⁴ poises at a temperature of 190 ° C. and a shear rate of 100 sec ⁻¹ .

<< Production Method and Conditions of Sheet Using Polyester (B1) Composition >> Polyester (B1) was used in an extruder having a screw diameter of 40 mmφ and L / D = 32 at a resin temperature of 180 ° C. and a T-width of 350 mm. Die (lip width 1.
0 mm) and the temperature of the first and second cooling rolls is 60
The sheet was molded under the condition of ° C to produce a sheet having a thickness of about 750 µm.

Further, the sheet obtained by the molding was vacuum-formed (manufactured by Asano Laboratory Co., Ltd., model name FLX-02 type, oven type double-sided infrared heating system), container (length: 140 mm,
Width: 140 mm, depth 45 mm) was created. There was no problem in sheet forming and vacuum forming, and the obtained container did not distort.

The obtained sheet, the MD and TD tensile rupture strength of the container (JIS K-7113), the rigidity according to the Olsen type stiffness meter (ASTM D-747),
Notched Izod impact strength at 23 ° C (JIS
K-7110), combustion calorific value, sheet formability, and biodegradability were tested, and the evaluation results are shown in Table 1.

(Example 2) The filling amount of talc was 40% by weight.
The same procedure as in Example 1 was carried out except that The melt viscosity was 2.7 × 10 ⁴ poise, and there was no problem in molding. The evaluation results of the obtained sheet and container are shown in Table 1.

Example 3 The same procedure as in Example 1 was carried out except that the filler was calcium carbonate having an average particle size of 1 μm. The melt viscosity was 2.0 × 10 ⁴ poise, and there was no problem in molding. Table 1 shows the evaluation results of the obtained sheets and containers.
Shown in.

Example 4 A 700-liter reactor was purged with nitrogen, and then 177 kg of 1,4-butanediol, 198 kg of succinic acid, and 25 kg of adipic acid were charged. The temperature is raised under a nitrogen stream and the temperature is set at 190 to 210 ° C for 3.5 hours.
Further stop the nitrogen, and under a reduced pressure of 20-2 mmHg 3.5.
The esterification reaction by dehydration condensation was performed over time.
The sample collected had an acid value of 9.6 mg / g, a number average molecular weight (Mn) of 6,100, and a weight average molecular weight (Mw).
Was 12,200. Subsequently, 20 g of tetraisopropoxytitanium as a catalyst was added under a nitrogen stream under normal pressure. Raise the temperature to 15-
The deglycol reaction was performed for 6.5 hours under a reduced pressure of 0.2 mmHg. The collected sample has a number average molecular weight (Mn)
Is 17,300, and the weight average molecular weight (Mw) is 46,
It was 400. The yield of this polyester (A2) was 337 kg when condensed water was removed.

4.66 kg of hexamethylene diisocyanate was added to a reactor containing 333 kg of polyester (A2), and a coupling reaction was carried out at 180 to 200 ° C. for 1 hour. The viscosity increased rapidly but no gelation occurred. Next, 1.70 kg of Irganox 1010 (manufactured by Ciba Geigy) as an antioxidant and 1.70 kg of calcium stearate as a lubricant were added, and stirring was continued for another 30 minutes. This reaction product was extruded into water with an extruder and cut into pellets with a cutter. 9
Polyester (B2) after vacuum drying at 0 ° C for 6 hours
The yield was 300 kg.

The polyester (B2) obtained was a slightly ivory-like white waxy crystal and had a melting point of 103.
° C, number average molecular weight (Mn) is 36,000, weight average molecular weight (Mw) is 200,900, MFR (190 ° C) is 0.52 g / 10 minutes, 10% of orthochlorophenol.
Viscosity of the solution is 680 poise, temperature 190 ℃, shear rate 1
The melt viscosity at 00 sec ⁻¹ was 2.2 × 10 ⁴ poise.

Then, a mixture of the polyester resin (B2) with 70 wt% of the resin and 30 wt% of talc having an average particle size of 5 μm was pelletized at a resin temperature of 200 ° C. as in Example 1, and the resin temperature at the time of sheet molding was 190. A sheet was manufactured under the same conditions as in Example 1 except that the temperature was changed to ° C. The melt viscosity was 2.9 × 10 ⁴ poise. Furthermore, a container of the same size was prepared by using the vacuum forming machine manufactured by Asano Laboratory Co., Ltd., which used the sheet in Example 1, but there was no problem in molding and no distortion occurred in the container.

(Comparative Example 1) The polyester (A1) was used as it was in the same manner as in Example 1. However, not only the pelletizing property using a twin-screw extruder was inferior, but also the strength was very weak and sheet forming was performed. I couldn't. Table 1 shows the evaluation results of the obtained sheets and containers.

[0062]

[Table 1]

[0063]

EFFECTS OF THE INVENTION A sheet formed from a composition in which a filler is mixed with the aliphatic polyester resin of the present invention has biodegradability when grown in soil or the like, and has a combustion calorific value of polypropylene even when incinerated. Compared to polyolefin resins such as polyethylene and polyethylene, it is about 1/3 lower than that of paper and has the same tensile strength and rigidity and impact strength as paper, making it a sheet for food containers, a sheet for packaging, and a sheet for general use. It is useful as a material for secondary molding.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Ryosuke Kamei 3-2 Chidori-cho, Kawasaki-ku, Kawasaki City, Kanagawa Prefecture Showa Denko K.K. -4

Claims (5)

[Claims] 1. A low combustion calorific value characterized by containing a filler in an aliphatic polyester mainly synthesized from glycol and an aliphatic dibasic acid or an acid derivative thereof and having a number average molecular weight of at least 10,000. Aliphatic polyester resin composition. 2. 10 to 70% by weight of an inorganic filler such as a metal oxide, hydroxide, sulfate, carbonate or silicate.
A low-combustion calorific value aliphatic polyester according to claim 1 or 2, which contains a polyester resin composition having a combustion calorific value of 5,000 kcal / kg or less and an Izod impact strength of 0.8 kg / cm ² or more. Resin composition. 3. A temperature of 190 ° C., a shear rate of 100 sec ⁻¹
The low-combustion calorific value aliphatic polyester resin composition according to claim 1, wherein the melt viscosity in the above is 1.0 × 10 ^{3 to} 1.0 × 10 ⁶ poise. 4. An aliphatic polyester resin composition molded article obtained by subjecting the aliphatic polyester resin composition sheet according to claim 3 to heat molding such as vacuum molding and pressure molding. 5. The polyester resin composition according to any one of claims 1 to 3, wherein the sheet has a rigidity of 4,500 kg / cm ² or more and a tensile rupture strength of 250 k in both MD and TD directions.
An aliphatic polyester resin composition sheet having a g / cm ² or more.