JP4993866B2 - Thermoplastic resin composition and molded body - Google Patents

Description

  The present invention relates to a thermoplastic resin composition and a molded article excellent in mechanical strength, thermal stability, and fluidity. More specifically, it comprises a thermoplastic resin composition comprising a polycarbonate resin and a fatty acid polyester, which has significantly improved thermal stability and excellent mechanical strength, such as falling weight impact strength and Izod impact strength, and the thermoplastic resin composition. It relates to a molded body. The thermoplastic resin composition of the present invention can be used in the fields of electrical and electronic equipment such as OA equipment, information / communication equipment, and home appliances, in the automobile field, and in the construction field.

  Polycarbonate resins are used in various fields because they are excellent in mechanical properties such as impact resistance, heat resistance, and transparency. Also, by mixing polycarbonate and other resins, such as ABS resin, cost reduction, polycarbonate molding processability, impact resistance thickness dependency, etc. are improved. Used in various fields. However, it is necessary to develop a polycarbonate resin composition having higher fluidity in order to cope with the recent trend of increasing size and thickness.

In recent years, in the fields of telecommunications equipment and automotive materials, polylactic acid, which is a plant-derived resin, has received much attention. This polylactic acid is made from plants such as corn and sugarcane, and is eventually decomposed into water and carbon dioxide (carbon neutral), so it has been developed as an environmentally friendly resin to reduce the environmental burden. Yes.
When polylactic acid, which is a fatty acid polyester, is added to polycarbonate, the fluidity is greatly improved. However, heat resistance, impact resistance, and transparency are greatly reduced. Heat resistance is improved by the addition of inorganic fillers, vegetable fibers and basic substances. Further, it is known that impact resistance can be improved by adding an elastomer or promoting compatibilization of polycarbonate and polylactic acid.

Fatty acid polyesters have low thermal stability and are limited in use as durable materials. Therefore, research and development for improving its thermal stability has been conducted. In order to improve heat resistance, the addition of an inorganic filler or vegetable fiber has been proposed, and the heat resistance is improved by increasing the crystallinity of the fatty acid polyester (see, for example, Patent Document 1 and Patent Document 2).
However, in these methods, depending on the intended use, the amount of filler and fiber added inevitably increases to increase the crystallinity of the fatty acid polyester, so that the fluidity and impact resistance may be reduced. It becomes.

  In addition, the heat resistance of fatty acid polyester is improved by alloying with a resin having high heat resistance. As an alloy of polycarbonate and polylactic acid, which is one of the fatty acid polyesters, a polycarbonate / polylactic acid alloy having a pearly luster. (For example, refer to Patent Document 3). However, Patent Document 3 does not mention thermal stability, and further improvement in impact resistance is desirable. Moreover, it is disclosed that polycarbonate and polylactic acid are reacted and compatibilized with a radical initiator to improve heat resistance (see, for example, Patent Document 4). However, in Patent Document 4, since aliphatic polyester carbonate is used, the heat resistance and impact resistance are insufficient, and it is desirable to set the physical property level to a higher level for practical use.

JP 2003-128900 A JP 2004-339454 A JP-A-7-109413 JP 2002-371172 A

  The present invention has been made in view of the above circumstances, and has heat resistance and thermal stability for a resin composition comprising a polycarbonate resin and a fatty acid polyester, which have both the mechanical properties of polycarbonate and the excellent fluidity of the fatty acid polyester. An object of the present invention is to provide a thermoplastic resin composition capable of improving the impact resistance and falling weight impact strength of the molded product.

  As a result of diligent studies to solve the above problems, the present inventors include a functional group that reacts with active hydrogen of the polycarbonate resin and / or fatty acid polyester in the resin composition comprising the polycarbonate resin and the fatty acid polyester. By adding the compound to be added at a predetermined ratio, the molecular weight reduction is suppressed by compatibilizing the polycarbonate and polylactic acid, the heat resistance and thermal stability are improved, the impact resistance is improved, and the falling weight impact strength. Also found to improve. The present invention has been completed based on such findings.

That is, the present invention provides the following thermoplastic resin composition and molded article.
1. (A) 100 parts by mass of a polycarbonate resin composition comprising 5 to 95% by mass of a polycarbonate resin containing a polycarbonate resin having a terminal phenolic hydroxyl group in a concentration range of 50 to 500 μmol / g and (B) 95 to 5% by mass of a fatty acid polyester. On the other hand, (C) A thermoplastic resin composition characterized by containing 0.005 to 10 parts by mass of a compound containing a functional group that reacts with the active hydrogen of the polycarbonate resin and / or fatty acid polyester.
2 . (B) The thermoplastic resin composition according to 1 above, wherein the fatty acid polyester is a copolymer of polylactic acid and / or lactic acid and other hydroxycarboxylic acid.
3 . (C) The thermoplastic resin composition according to 1 or 2 above, wherein the compound containing a functional group that reacts with the active hydrogen of the polycarbonate resin and / or the fatty acid polyester is a carbodiimide compound and / or an isocyanate compound.
4 . (A) The thermoplastic resin composition according to any one of 1 to 3 above, wherein the polycarbonate resin is a polycarbonate resin containing a polycarbonate-polyorganosiloxane copolymer or a polycarbonate-polyorganosiloxane copolymer.
5 . The molded object which consists of a thermoplastic resin composition in any one of said 1-4 .
6 . The molded article according to 5 above, which is used for any one of OA equipment, information / communication equipment, automobile parts, building members, and home appliances.

The thermoplastic resin composition of the present invention is made compatible by adding a compound containing a functional group that reacts with active hydrogen of a polycarbonate resin and / or a fatty acid polyester to a resin composition comprising a polycarbonate and a fatty acid polyester. Thus, a molded article having both the mechanical properties and the excellent fluidity of the fatty acid polyester, excellent heat resistance and thermal stability, and improved impact resistance and falling weight impact strength can be obtained.
By improving these characteristics, plastic molded products can be used for a long time, and can be used for heat-resistant applications and large thin-wall molding.
Therefore, the thermoplastic resin composition of the present invention can be advantageously used for OA equipment, information / communication equipment, automobile parts, building members, home appliances, and the like.

  In the thermoplastic resin composition of the present invention, the polycarbonate resin of the component (A) is not particularly limited, and various types can be mentioned, but the general formula (1)

A polymer having a repeating unit having a structure represented by the formula:
In the general formula (1), R ¹ and R ² are each a halogen atom (for example, chlorine, fluorine, bromine, iodine) or an alkyl group having 1 to 8 carbon atoms (for example, a methyl group, an ethyl group, a propyl group, An isopropyl group, various butyl groups (n-butyl group, isobutyl group, sec-butyl group, tert-butyl group), various pentyl groups, various hexyl groups, various heptyl groups, various octyl groups).
m and n are each an integer of 0 to 4. When m is 2 to 4, R ¹ may be the same as or different from each other, and when n is 2 to 4, R ² is They may be the same or different.
Z is an alkylene group having 1 to 8 carbon atoms or an alkylidene group having 2 to 8 carbon atoms (for example, methylene group, ethylene group, propylene group, butylene group, pentylene group, hexylene group, ethylidene group, isopropylidene group, etc.), A cycloalkylene group having 5 to 15 carbon atoms or a cycloalkylidene group having 5 to 15 carbon atoms (for example, a cyclopentylene group, a cyclohexylene group, a cyclopentylidene group, a cyclohexylidene group), or a single bond, —SO ₂ -, -SO-, -S-, -O-, -CO- bond, or the following formula (2) or formula (2 ')

The bond represented by is shown.
The polymer is usually represented by the general formula (3)

［式中、Ｒ¹、Ｒ²、Ｚ、ｍ及びｎは、上記一般式（１）と同じである。］

[Wherein, R ¹ , R ² , Z, m and n are the same as those in the general formula (1). ]

It can manufacture easily by making carbonate precursors, such as phosgene, and dihydric phenol represented by these.
That is, for example, it can be produced by a reaction of a dihydric phenol and a carbonate precursor such as phosgene in a solvent such as methylene chloride in the presence of a known acid acceptor or molecular weight regulator. It can also be produced by a transesterification reaction between a dihydric phenol and a carbonate precursor such as a carbonate compound.
Various things can be mentioned as a dihydric phenol represented by the said General formula (3).
In particular, 2,2-bis (4-hydroxyphenyl) propane [common name, bisphenol A] is preferable.
Examples of dihydric phenols other than bisphenol A include bis (4-hydroxyphenyl) methane; 1,1-bis (4-hydroxyphenyl) ethane; bis (1,2-bis (4-hydroxyphenyl) ethane, etc. 4-hydroxyphenyl) alkane, 1,1-bis (4-hydroxyphenyl) cyclohexane; bis (4-hydroxyphenyl) cycloalkane such as 1,1-bis (4-hydroxyphenyl) cyclodecane, 4,4′-dihydroxy Examples include diphenyl, bis (4-hydroxyphenyl) oxide, bis (4-hydroxyphenyl) sulfide, bis (4-hydroxyphenyl) sulfone, bis (4-hydroxyphenyl) sulfoxide, and bis (4-hydroxyphenyl) ketone. .
In addition, hydroquinone etc. are mentioned as dihydric phenol.
These dihydric phenols may be used alone or in combination of two or more.
Examples of the carbonate compound include diaryl carbonates such as diphenyl carbonate, and dialkyl carbonates such as dimethyl carbonate and diethyl carbonate.

The polycarbonate resin may be a homopolymer using one of the above dihydric phenols, or may be a copolymer using two or more.
Furthermore, the thermoplastic random branched polycarbonate resin obtained by using a polyfunctional aromatic compound together with the said bihydric phenol may be sufficient.
The polyfunctional aromatic compound is generally called a branching agent, and specifically, 1,1,1-tris (4-hydroxyphenyl) ethane, α, α ′, α ″ -tris (4-hydroxy Phenyl) -1,3,5-triisopropylbenzene, 1- [α-methyl-α- (4′-hydroxyphenyl) ethyl] -4- [α ′, α′-bis (4 ″ -hydroxyphenyl) ethyl Benzene, phloroglucin, trimellitic acid, 1-3-bis (o-cresol) and the like.
Polycarbonate resins having such characteristics are commercially available as aromatic polycarbonate resins such as Teflon FN3000A, FN2500A, FN2200A, FN1900A, FN1700A, and FN1500 [trade name, manufactured by Idemitsu Kosan Co., Ltd.].

The polycarbonate resin used in the present invention is not only a homopolymer produced using only the above dihydric phenol, but also a polycarbonate-polyorganosiloxane copolymer (hereinafter abbreviated as PC-POS copolymer). Or a polycarbonate resin containing a PC-POS copolymer, which is preferable because impact resistance is increased and flame retardancy is also improved. Further, from the viewpoint of flame retardancy and impact resistance, the PC-POS copolymer alone is more preferable as the polycarbonate resin used in the present invention.
When the amount of siloxane in the PC-POS copolymer or the polycarbonate resin containing the PC-POS copolymer is 0.1 to 4% by mass, preferably 0.3 to 2% by mass, the total amount of the siloxane is small. Flame retardancy and impact resistance are insufficient, and if it exceeds 4% by mass, heat resistance and flame retardancy are lowered.
There are various types of PC-POS copolymers. Preferably, the following general formula (1)

［式中、Ｒ¹、Ｒ²、Ｚ、ｍ及びｎは、上記と同じである。］

[Wherein, R ¹ , R ² , Z, m and n are the same as described above. ]

A polycarbonate part having a repeating unit having a structure represented by the following general formula (4):

［式中、Ｒ³、Ｒ⁴及びＲ⁵は、それぞれ水素原子、炭素数１〜５のアルキル基（例えば、メチル基、エチル基、プロピル基、ｎ−ブチル基、イソブチル基など）又はフェニル基であり、ｐ及びｑは、それぞれ０又は１以上の整数であるが、ｐとｑとの合計は１以上の整数である。］

[Wherein R ³ , R ⁴ and R ⁵ are each a hydrogen atom, an alkyl group having 1 to 5 carbon atoms (for example, a methyl group, an ethyl group, a propyl group, an n-butyl group, an isobutyl group) or a phenyl group. P and q are each an integer of 0 or 1 or more, but the sum of p and q is an integer of 1 or more. ]

The polyorganosiloxane part which has a repeating unit of the structure represented by these.
Here, the polymerization degree of the polycarbonate part is preferably 3 to 100, and the polymerization degree of the polyorganosiloxane part is preferably 2 to 500.

The PC-POS copolymer is a block comprising a polycarbonate part having a repeating unit represented by the general formula (1) and a polyorganosiloxane part having a repeating unit represented by the general formula (4). It is a copolymer.
Such a PC-POS copolymer has, for example, a polycarbonate oligomer (hereinafter abbreviated as a PC oligomer) constituting a polycarbonate part produced in advance and a reactive group at the terminal constituting the polyorganosiloxane part. A polyorganosiloxane (for example, polydimethylsiloxane (PDMS), polydialkylsiloxane such as polydiethylsiloxane or polymethylphenylsiloxane) is dissolved in a solvent such as methylene chloride, chlorobenzene, chloroform, etc., and a sodium hydroxide aqueous solution of bisphenol And triethylamine or trimethylbenzylammonium chloride as a catalyst, and can be produced by interfacial polycondensation reaction.
Further, a PC-POS copolymer produced by the method described in Japanese Patent Publication No. 44-30105 or the method described in Japanese Patent Publication No. 45-20510 can also be used.

Here, the PC oligomer having the repeating unit represented by the general formula (1) is a solvent method, that is, in the presence of a known acid acceptor and molecular weight regulator in a solvent such as methylene chloride. ) And a carbonate precursor such as phosgene or a carbonic acid ester compound can be easily produced.
For example, in a solvent such as methylene chloride, in the presence of a known acid acceptor or molecular weight regulator, by reaction between a dihydric phenol and a carbonate precursor such as phosgene, or like a dihydric phenol and a carbonate compound. It can be produced by transesterification with a carbonate precursor.
As the carbonate compound, the same ones as described above can be used, and as the molecular weight regulator, the same ones as the terminal terminators described later can be used.

In the present invention, the PC oligomer used for the production of the PC-POS copolymer may be a homopolymer using one of the above dihydric phenols, or may be a copolymer using two or more. .
Furthermore, the thermoplastic random branched polycarbonate resin obtained by using a polyfunctional aromatic compound together with the said bihydric phenol may be sufficient.
Furthermore, as a polycarbonate resin used for this invention, following General formula (5)

［式中、Ｒ⁶は炭素数１〜３５のアルキル基を示し、ａは０〜５の整数を示す。］
で表わされる末端基を有するポリカーボネート樹脂も好適である。

[Wherein R ⁶ represents an alkyl group having 1 to 35 carbon atoms, and a represents an integer of 0 to 5. ]
A polycarbonate resin having a terminal group represented by the formula is also suitable.

In the general formula (5), R ⁶ is an alkyl group having 1 to 35 carbon atoms, and may be linear or branched.
The bond position may be any of p-position, m-position and o-position, but p-position is preferred.
The polycarbonate resin having a terminal group represented by the general formula (5) can be easily produced by reacting a dihydric phenol with phosgene or a carbonate compound.

For example, in a solvent such as methylene chloride, by reaction of a dihydric phenol with a carbonate precursor such as phosgene in the presence of a catalyst such as triethylamine and a specific end-stopper, or like dihydric phenol and diphenyl carbonate. It is produced by a transesterification reaction with a carbonate precursor.
Here, the dihydric phenol may be the same as or different from the compound represented by the general formula (3).
Further, it may be a homopolymer using one kind of the above dihydric phenol or a copolymer using two or more kinds.
Furthermore, the thermoplastic random branched polycarbonate resin obtained by using a polyfunctional aromatic compound together with the said bihydric phenol may be sufficient.

Examples of the carbonate compound include diaryl carbonates such as diphenyl carbonate and dialkyl carbonates such as dimethyl carbonate and diethyl carbonate.
As the terminal terminator, a phenol compound in which the terminal group represented by the general formula (5) is formed may be used. That is, it is a phenol compound represented by the following general formula (6).

［式中、Ｒ⁶は炭素数１〜３５のアルキル基を示し、ａは０〜５の整数を示す。］

[Wherein R ⁶ represents an alkyl group having 1 to 35 carbon atoms, and a represents an integer of 0 to 5. ]

These alkylphenols include phenol, p-cresol, p-tert-butylphenol, p-tert-octylphenol, p-cumylphenol, p-nonylphenol, docosylphenol, tetracosylphenol, hexacosylphenol, octacosy. Examples include ruphenol, triacontylphenol, dotriacontylphenol, and tetratriacontylphenol. These may be one kind or a mixture of two or more kinds.
In addition, these alkylphenols may be used in combination with other phenolic compounds as long as the effects are not impaired.
The polycarbonate resin produced by the above method has a terminal group represented by the general formula (5) at one or both ends of the molecule.

The polycarbonate resin used as the component (A) has a viscosity average molecular weight of usually 14,000 to 40,000. When the viscosity average molecular weight is 14,000 or more, the resulting thermoplastic resin composition has sufficient heat resistance and mechanical properties, and when the viscosity average molecular weight is 40,000 or less, the resulting thermoplastic resin is obtained. This is because the moldability of the resin composition is improved.
The viscosity average molecular weight of the polycarbonate resin is preferably 14,000 to 30,000, and more preferably 17,000 to 22,000 from the viewpoint of balance such as mechanical properties.
The viscosity average molecular weight (Mv) was determined by measuring the viscosity of the methylene chloride solution at 20 ° C. using an Ubbelohde viscometer, and determining the intrinsic viscosity [η] from this, [η] = 1.23 × 10 ⁻ It is a value calculated by the equation of ⁵ Mv ^0.83 .
In this invention, what has a terminal phenolic hydroxyl group as a polycarbonate resin which has active hydrogen is preferable. The terminal phenolic hydroxyl group concentration in this polycarbonate resin is preferably 50 to 500 μmol / g, more preferably 80 to 300 μmol / g, and still more preferably 100 to 220 μmol / g. Within the above range, reaction compatibilization between the polycarbonate and the fatty acid polyester is promoted, and the thermal stability and the like are improved.

In the thermoplastic resin composition of the present invention, examples of the fatty acid polyester as the component (B) include polyesters such as polylactic acid and polymalic acid. Among these, polylactic acid and a copolymer of lactic acid and other hydroxycarboxylic acid are preferable. Polylactic acid is synthesized by ring-opening polymerization from a cyclic dimer of lactic acid, usually called lactide, and its production method is described in US Pat. No. 1,995,970 and US Pat. No. 2,362,511. U.S. Pat. No. 2,683,136 and the like.
Copolymers of lactic acids and other hydroxycarboxylic acids are usually synthesized by ring-opening polymerization from a cyclic ester intermediate of lactide and hydroxycarboxylic acid, and the production method is disclosed in US Pat. No. 3,635,956. And U.S. Pat. No. 3,797,499.
When producing polylactic acid or a copolymer of lactic acid and other hydroxycarboxylic acid by direct dehydration polycondensation without using ring-opening polymerization, other hydroxycarboxylic acid and other hydroxycarboxylic acid may be added as necessary. Preferably, azeotropic dehydration condensation is performed in the presence of an organic solvent, in particular, a phenyl ether solvent, and particularly preferably, water is removed from the solvent distilled by azeotropic distillation, and the solvent in a substantially anhydrous state is removed from the reaction system. By polymerizing by the method of returning to (1), a fatty acid polyester having a polymerization degree suitable for the present invention can be obtained.

As raw lactic acids, any of L- and D-lactic acid, a mixture thereof, or lactide which is a dimer of lactic acid can be used.
Examples of other hydroxycarboxylic acids that can be used in combination with lactic acids include glycolic acid, 3-hydroxybutyric acid, 4-hydroxybutyric acid, 4-hydroxyvaleric acid, 5-hydroxyvaleric acid, and 6-hydroxycaproic acid. Cyclic ester intermediates of hydroxycarboxylic acid, for example, glycolide, which is a dimer of glycolic acid, and ε-caprolactone, which is a cyclic ester of 6-hydroxycaproic acid, can also be used.
In the production of the fatty acid polyester, an appropriate molecular weight regulator, a branching agent, other modifiers and the like can be blended.
In addition, lactic acids and hydroxycarboxylic acids as copolymer components can be used alone or in combination of two or more, and two or more of the obtained fatty acid polyesters may be mixed and used.
In the present invention, polylactic acid which is a polymer of only lactic acids is preferably used, and poly L-lactic acid resin is particularly preferable.

The fatty acid polyester of component (B) used in the present invention preferably has a large molecular weight from the viewpoint of thermal properties and mechanical properties, and preferably has a weight average molecular weight of 30,000 or more.
In the present invention, the content ratio of the polycarbonate resin as the component (A) and the fatty acid polyester as the component (B) is in the range of 5:95 to 95: 5, preferably in the range of 20:80 to 80:20. .
When the content ratio of the component (A) and the component (B) is within the above range, the thermoplastic resin composition of the present invention has good mechanical strength, thermal stability, and molding stability, and will be described later. Dispersion of the compound containing a functional group that reacts with the active hydrogen of the polycarbonate resin and / or fatty acid polyester as the component (C) becomes good.

In the thermoplastic resin composition of the present invention, the functional group that reacts with the active hydrogen of the (C) component polycarbonate resin and / or fatty acid polyester is preferably a carbodiimide group, an isocyanate group, an oxazoline group, or an oxazole group. Alternatively, from the viewpoint of reactivity with the active hydrogen of the fatty acid polyester, a carbodiimide group (general formula: RN = C = NR), an isocyanate group (general formula: R = N = C = O) (where R is an organic group). The compound having is more preferable. Particularly preferred are alicyclic diisocyanates, aromatic diisocyanates, aliphatic diisocyanates, alicyclic carbodiimides, aromatic carbodiimides, and aliphatic carbodiimides. Specifically, 1,5-naphthylene diisocyanate, diphenylmethane-4,4′-diisocyanate, 3,3′-dimethyldiphenylmethane-4,4′-diisocyanate, 1,3-phenylene diisocyanate, 1,4-phenylene diisocyanate 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, a mixture of 2,4-tolylene diisocyanate and 2,6-tolylene diisocyanate, hexamethylene diisocyanate, cyclohexane-1,4-diisocyanate, xylylene diene Isocyanate, isophorone diisocyanate, dicyclohexylmethane-4,4'-diisocyanate, methylcyclohexane diisocyanate, 1,3-bis (isocyanatomethyl) cyclohexane, tetramethylxylylene diisocyanate And dicyclohexylcarbodiimide, diisopropylcarbodiimide, dimethylcarbodiimide, diisobutylcarbodiimide, dioctylcarbodiimide, t-butylisopropylcarbodiimide, diphenylcarbodiimide, di-t-butylcarbodiimide, di-β-naphthylcarbodiimide, etc. Among these, dicyclohexylcarbodiimide and 1,3-bis (isocyanatomethyl) cyclohexane are preferable from the viewpoint of industrial availability. This (C) component may be used individually by 1 type, or may be used in combination of 2 or more type.
Component (C) is added in an amount of 0.005 to 10 parts by mass, preferably 0.01 to 5 parts by mass, more preferably 100 parts by mass of the total amount of components (A) and (B). 0.1 to 3 parts by mass.

The thermoplastic resin composition of the present invention can be obtained by blending the above components (A), (B) and (C), and other components as necessary, and melt-kneading. .
For this blending and kneading, a commonly used method, for example, a ribbon blender, a Henschel mixer, a Banbury mixer, a drum tumbler, a single screw extruder, a twin screw extruder, a kneader, a multi screw extruder or the like is used. It can be done by a method.
In addition, as for the heating temperature in the case of melt kneading, 220-280 degreeC is preferable.

This invention also provides the molded object which consists of the said thermoplastic resin composition. The molding temperature of the thermoplastic resin composition of the present invention is preferably 220 to 280 ° C.
The thermoplastic resin composition of the present invention is a molded article having both the mechanical properties of polycarbonate and the excellent fluidity of fatty acid polyester, and good thermal stability, and improved impact resistance and impact strength. By improving these characteristics, it becomes possible to use plastics molded products for a long period of time, for heat-resistant applications, and for large-sized thin-wall molding. In addition, by using a polycarbonate-polyorganosiloxane copolymer in combination, flame retardancy can also be improved, and it can be advantageously used in OA equipment, information / communication equipment, automobile parts, building components, and home appliances. Can do.

EXAMPLES Next, although an Example demonstrates this invention still in detail, this invention is not limited at all by these examples.
In the following examples and comparative examples, performance evaluation was performed by the following method.
(1) Heat-resistant retention rate: An exposure test is performed in an oven at 80 ° C. for 500 hours, and elongation is maintained by a tensile test in accordance with JIS K7162 [test conditions, etc .: 23 ° C., wall thickness 0.32 mm (1/8 inch)]. The rate was measured.
(2) Thermal stability: After being kept at 260 ° C. for 20 minutes in a molding machine, an 80 × 40 × 3 mm square plate was molded and visually observed. Those with excellent appearance were marked with ◎, and those with good appearance were marked with ◯.
(3) Drop weight impact strength (test specimen thickness: 2 mm): Measured according to JIS K7211, at a weight of 3.76 kg, a drop speed of 5 m / sec, and 23 ° C.
(4) Izod impact strength: Measured according to ASTM D256. [Test conditions, etc .: 23 ° C., wall thickness 0.32 mm (1/8 inch)]
(5) Flame retardancy: A vertical combustion test was conducted in accordance with the Underwriters Laboratory Subject 94 under the UL94 standard with a test piece thickness of 3.0 mm.
In Table 1, “−” of flame retardancy is not measured, and “NG” is also not good flame retardance (abbreviation of no good). The flame retardancy can be enhanced by adding a drip inhibitor or the like separately.

Examples 1-5 and Comparative Examples 1-3
Each component of (A) to (C) is blended at the ratio shown in Table 1, supplied to a vent type twin screw extruder (model name TEM35, manufactured by Toshiba Machine Co., Ltd.), melt-kneaded at 260 ° C, Pelletized.
In all Examples and Comparative Examples, phosphorus antioxidants (trade name “ADK STAB PEP-36” manufactured by Asahi Denka Kogyo Co., Ltd.) and phenolic antioxidants Irganox 1076 [Ciba Specialty Chemicals, Ltd.] were used as stabilizers. 0.1 parts by mass of each of the product name and product name].
Next, the obtained pellets were dried at 100 ° C. for 10 hours, and then injection molded at a molding temperature of 240 ° C. (mold temperature of 80 ° C.) to obtain each test piece. Each performance was evaluated by the performance evaluation method using the obtained test piece.
Table 1 shows the performance evaluation results of each example and comparative example.

The components (A) to (C) in Table 1 are as follows.
(A) -1: 100 parts by mass of phenolic end group-modified polycarbonate (Teflon FN2500 (Mv = 23800) manufactured by Idemitsu Kosan Co., Ltd.), 0.1 part by mass of tetramethylammonium hydroxide was mixed and extruded at 280 ° C. Pellets were prepared (terminal phenolic hydroxyl group concentration: 80 μmol / g)
(A) -2: Bisphenol A polycarbonate (FN1700A (Mv = 17500) manufactured by Idemitsu Kosan Co., Ltd., terminal phenolic hydroxyl group concentration: 0 μmol / g)
(A) -3: PC-PDMS (silicone copolymer polycarbonate)
(The viscosity average molecular weight was 17,000, and the PDMS (polydimethylsiloxane) content was 4.0 mass%. The viscosity was adjusted according to Production Example 4 of JP-A-2002-12755.)
(B) -1: crystalline polylactic acid H-400 (manufactured by Mitsui Chemicals, Inc.)
(B) -2: Amorphous polylactic acid H-280 (manufactured by Mitsui Chemicals, Inc.)
(C) -1: Dicyclohexylcarbodiimide (Nisshinbo Co., Ltd., Carbodilite LA-1)
(C) -2: 1,3-bis (isocyanatomethyl) cyclohexane
(Takenate 600, manufactured by Mitsui Takeda Chemical)

From Table 1, the following was found.
(1) As shown in Examples 1 to 5, by adding a compound containing a functional group that reacts with active hydrogen of (C) polycarbonate and / or fatty acid polyester to polycarbonate / polylactic acid alloy, heat resistance is increased. A molded article of polycarbonate / polylactic acid alloy having improved properties (heat retention ratio), thermal stability, falling weight impact strength, and Izod impact strength can be obtained. Moreover, a flame retardance can be improved by using together a polycarbonate-silicone copolymer.
(2) From Comparative Example 1, since the component (C) is not added, the effect of compatibilization cannot be obtained, so the heat resistance and thermal stability are low.
(3) From Comparative Example 2, when the amount of component (C) added is too small, even if the terminal phenolic hydroxyl group concentration in the polycarbonate is within the scope of the claims, the reaction effect is small and the thermal stability is insufficient. .
(4) From Comparative Example 3, if the amount of component (C) is too large, it will react too much, resulting in poor heat resistance and thermal stability, as well as poor dispersion of component (C) and Izod impact. The strength is reduced, and irregularities appear on the molded body.

Claims (6)

(A) 100 parts by mass of a polycarbonate resin composition comprising 5 to 95% by mass of a polycarbonate resin containing a polycarbonate resin having a terminal phenolic hydroxyl group in a concentration range of 50 to 500 μmol / g and (B) 95 to 5% by mass of a fatty acid polyester. On the other hand, (C) 0.005-10 mass parts of compounds containing the functional group which reacts with the active hydrogen of polycarbonate resin and / or fatty acid polyester is contained, The thermoplastic resin composition characterized by the above-mentioned. (B) The thermoplastic resin composition according to claim 1 , wherein the fatty acid polyester is a copolymer of polylactic acid and / or lactic acid and other hydroxycarboxylic acid. (C) The thermoplastic resin composition according to claim 1 or 2 , wherein the compound containing a functional group that reacts with the active hydrogen of the polycarbonate resin and / or fatty acid polyester is a carbodiimide compound and / or an isocyanate compound. The thermoplastic resin composition according to any one of claims 1 to 3 , wherein (A) the polycarbonate resin is a polycarbonate-polyorganosiloxane copolymer or a polycarbonate resin containing a polycarbonate-polyorganosiloxane copolymer. The molded object which consists of a thermoplastic resin composition in any one of Claims 1-4 . The molded article according to claim 5 , which is used for any one of OA equipment, information / communication equipment, automobile parts, building members, and home appliances.