JPH09279004A - Resin composition and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a resin composition having improved compatibility and reduced delamitation and retaining ductility by mixing an aromatic polycarbonate resin with a specified styrene/ester copolymer. SOLUTION: This composition is prepared by mixing 20-90wt.% aromatic polycarbonate resin (A) with 0-77wt.% styrene resin (B) and 3-80wt.% styrene copolymer (C) comprising 60-95wt.% styrene monomer and 40-5wt.% at least one monomer selected among alkyl (meth)acrylates. An example of processes for producing the same comprises melt-kneading part of component A and component C (especially in the presence of a transesterification catalyst) and mixing the remainder of component A with component B to obtain a composition having the above composition. The composition can provide a material suited for, e.g. sheets having improved compatibility of the aromatic polycarbonate with the styrene resin and reduced delamination, and retaining the elongation of the resin.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a resin composition comprising an aromatic polycarbonate and a styrene resin, which has excellent heat resistance and ductility and is easy to mold.
In particular, the present invention relates to a resin composition suitable for a sheet application in which transparency is sometimes required.

[0002]

2. Description of the Related Art Aromatic polycarbonate resins are excellent in heat resistance, mechanical properties and transparency and are used in various fields including sheet applications. However, the aromatic polycarbonate resin generally has poor fluidity, and improvement in molding processability is desired. In order to improve the fluidity of the aromatic polycarbonate resin, it has been proposed to blend a styrene resin (hereinafter PS) with the aromatic polycarbonate resin (hereinafter PC).

Japanese Patent Laid-Open Nos. 61-19656 and 61-1
In 08617, a composition of PC and PS is proposed. Also, in order to improve the compatibility of PC and PS, PC and P
It has been proposed to use a graft polymer of S as a compatibilizing agent, and JP-A-2-29412 and JP-A-63-15941 have been proposed.
5, JP-A-63-196612, JP-A-55-5000
No. 9 discloses a graft polymer obtained by copolymerizing PC having an unsaturated terminal and a vinyl monomer, and Japanese Patent Laid-Open No. 5-2102
02279 discloses a graft compound by a transesterification reaction between PC and PS having a COOH group.
JP-A-2-41357 discloses a system in which a PC having an initiator group is used as an initiator to polymerize a vinyl monomer.

However, PC and PS are poorly compatible with each other, and even with these proposals, there is a case where delamination is observed in the molded product, and the expression of mechanical properties cannot be said to be sufficient, and the impact resistance and ductility of PC are high. And other properties are impaired.

[0005]

Therefore, an object of the present invention is to show an effective compatibilizing method for an aromatic polycarbonate resin and a styrene resin, without showing delamination and maintaining the ductility of the aromatic polycarbonate resin. It is to provide a resin composition in which a group polycarbonate resin and a styrene resin are mixed and to show a production method.

[0006]

In compounding an aromatic polycarbonate resin and a styrene resin, a specific styrene copolymer having an ester group is used as the styrene resin, or an aromatic polycarbonate resin and a styrene resin are used. It is effective for the above purpose to add a specific styrene-based copolymer having an ester group to the resin composite, and especially to pre-knead the aromatic polycarbonate resin and the specific styrene-based copolymer, It is possible to form a graft polymer by transesterification between the aromatic polycarbonate resin and a part of the styrenic copolymer in advance by adding an exchange catalyst and pre-kneading.
The inventors have found that the compatibility is improved, delamination is reduced, and the above problems are solved, and the present invention has been achieved.

That is, the present invention provides the following (1) to
(3).

(1) (a) 20 to 90% by weight of aromatic polycarbonate resin, (b) 0 to 77% by weight of styrene resin, (c) 60 to 95% by weight of styrene monomer, alkyl acrylate or methacrylic acid. 40-5% by weight of one or more monomers selected from alkyl esters
The present invention relates to a resin composition containing 3 to 80% by weight of a styrene copolymer.

(2) 60 to 95% by weight of (a ') aromatic polycarbonate resin and (c) styrenic monomer, 40 to 5% by weight of at least one monomer selected from alkyl acrylate or alkyl methacrylate.
A styrene-based copolymer is composed of a styrene-based copolymer, which is melted and kneaded in advance, and then the necessary residual amount of (a '') aromatic polycarbonate resin,
(B) Styrene-based resin is mixed, and (a) (= (a ') +
(A '')) 20 to 90% by weight of aromatic polycarbonate resin, (b) 0 to 77% by weight of styrene resin, and (c) 3 to 80% by weight of styrene copolymer. 1) A method for producing the resin composition described above.

(3) 60 to 95% by weight of (a ') aromatic polycarbonate resin and (c) styrenic monomer, 40 to 5% by weight of at least one monomer selected from alkyl acrylate or alkyl methacrylate.
The transesterification catalyst is added to 0.0001 to 100 parts by weight of the resin component including the styrene copolymer.
After adding 0.01 part by weight and melt-kneading in advance,
A required amount of (a '') aromatic polycarbonate resin,
(B) Styrene-based resin is mixed, and (a) (= (a ') +
(A ″)) 20 to 90% by weight of aromatic polycarbonate resin, (b) 0 to 77% by weight of styrene resin, and (c) 3 to 80% by weight of styrene copolymer. 1) A method for producing the resin composition described above.

Hereinafter, the present invention will be described in detail.

As the aromatic polycarbonate of the present invention, those produced by a method of reacting an aromatic dihydric phenol with phosgene or a transesterification reaction of an aromatic dihydric phenol with a carbonic acid diester can be used.

The aromatic dihydric phenols include bis (4-hydroxyphenyl) methane and 1,1-bis (4
-Hydroxylphenyl) ethane, 1,1-bis (4-
Hydroxyphenyl) propane, 2,2-bis (4-hydroxyphenyl) propane, 2,2-bis (4-hydroxyphenyl) butane, 2,2-bis (4-hydroxyphenyl) pentane, 2,2-bis ( 4-hydroxyphenyl) isopentane, 2,2-bis (4-hydroxyphenyl) hexane, 2,2-bis (4-hydroxyphenyl) isohexane, bis (4-hydroxyphenyl) phenylmethane, bis (4-hydroxyphenyl)
Diphenylmethane, 2,2-bis (4-hydroxy-3)
-Methylphenyl) propane, 2,2-bis (4-hydroxy-3,5-dimethylphenyl) propane, 1,1
-Bis (4-hydroxyphenyl) cyclohexane, dihydroxydiphenyl sulfone, dihydroxydiphenyl sulfide, dihydroxydiphenyl ether, hydroquinone, resorcin, o-methylresorcin, o-
Cumyl resorcin is exemplified, but especially 2,2-bis (4-hydroxyphenyl) propane (hereinafter BisA)
Is preferred. These dihydric phenols may be used alone or in combination of two or more, or may be a blend of respective polymers. PC used in the present invention
The viscosity average molecular weight is preferably 10,000 to 100,000, and particularly preferably 15,000 to 40,000 in view of the balance between moldability and mechanical properties.

The styrene resin in the present invention is polystyrene or a copolymer of a styrene monomer and another vinyl monomer, and has a styrene monomer composition of 50% by weight or more. These PS are bulk polymerization, solution polymerization,
It can be produced by a known polymerization method such as emulsion polymerization or suspension polymerization.

Vinyl monomers copolymerized with styrene include acrylic acid, methacrylic acid, methyl acrylate, ethyl acrylate, n-butyl acrylate, methyl methacrylate, ethyl methacrylate, n-butyl methacrylate, maleic anhydride, Acrylonitrile, methacrylonitrile, N-maleimide, N-methylmaleimide, N-
Phenylmaleimide, N-cyclohexylmaleimide,
Examples thereof include α-methylstyrene and p-methylstyrene, but especially methacrylic acid, methyl acrylate, ethyl acrylate, n-butyl acrylate, methyl methacrylate, ethyl methacrylate, n-butyl methacrylate, maleic anhydride. Acids are preferred. These vinyl monomers are 1
You may use it by 1 type or a combination of 2 or more types. Further, two or more kinds of styrene resins may be used in combination.

The weight average molecular weight (GPC method, standard polystyrene conversion) of the styrene resin is 30,000.
Those of up to 650000 are preferable. When various styrenic resins are used in combination, the molecular weight of each styrenic resin does not have to be in this range, but it is preferable that they fall in this range as a whole.

The styrene resin may be the same as the specific styrene copolymer having a specific ester group described below. In particular, when the aromatic polycarbonate resin and the styrene-based copolymer having a specific ester group are pre-kneaded and then the aromatic polycarbonate resin and the styrene-based resin are further blended to produce a composition, it is preferable that both are the same. It is often preferable because of its solubility. In this case, the amount ratio of each component may be appropriately distributed to the (b) styrene-based resin and the (c) styrene-based copolymer, and as a result, may be within the component range specified in the present invention.

The styrene copolymer referred to in the present invention has a composition of 60 to 95% by weight of a styrene monomer and 40 to 5% by weight of at least one monomer selected from alkyl acrylate or alkyl methacrylate. It is a copolymer having an ester group.

As the styrene type monomer, styrene,
α-Methylstyrene, p-methylstyrene and the like are exemplified, but styrene is usually used.

Examples of the alkyl acrylate or methacrylic acid alkyl ester include methyl acrylate,
Examples include ethyl acrylate, n-butyl acrylate, isobutyl acrylate, 2-ethylhexyl acrylate, methyl methacrylate, ethyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, 2-ethylhexyl methacrylate, and the like. Methyl acrylate, ethyl acrylate, n-butyl acrylate, methyl methacrylate, ethyl methacrylate and n-butyl methacrylate are preferred. These monomers may be used alone or in combination of two or more. Further, two or more kinds of styrene-based copolymers may be used in combination. The weight average molecular weight (GPC method, standard polystyrene conversion) of the styrene-based copolymer is preferably 30,000 to 650,000. Even when two or more styrene-based copolymers are used in combination, it is preferable that they fall within this range as a whole.

The method for obtaining the resin composition of the present invention is as follows:
A composition comprising the aromatic polycarbonate resin, a styrene resin, and a styrene copolymer is added at 230 ° C to 330 ° C.
Melt kneading can be carried out at a temperature in the range of 270 ° C., more preferably 270 ° C. to 320 ° C. using a known method such as a Banbury mixer, a kneader, a single-screw or twin-screw extruder.

However, as a method for obtaining the resin composition of the present invention, the aromatic polycarbonate resin and the styrene-based copolymer are melt-kneaded in advance, and then the required amount of the aromatic polycarbonate resin and the styrene-based resin is blended. It is more preferable from the viewpoint of improving solubility and dispersibility. The pre-kneading is carried out by using 30 to 70% by weight of the aromatic polycarbonate resin,
Styrene-based copolymer with a composition of 70 to 30% by weight of 230 to
It is preferably carried out at a temperature of 330 ° C, more preferably 270-320 ° C. A Banbury mixer, a kneader, or a single-screw or twin-screw extruder can be used as the apparatus, but the melt-kneading is preferably performed for several minutes or more.
If necessary, an aromatic polycarbonate resin and a styrene-based resin (styrene-based copolymer) are added to this pre-kneaded composition so as to obtain a desired composition, and the mixture is heated at 230 ° C to 33 ° C.
Melt kneading can be performed at 0 ° C. using a known method such as a Banbury mixer, a kneader, a single-screw or twin-screw extruder.

Further, at the time of preliminary kneading, 0.0001 to 0.01 part by weight, more preferably 0.0003 to 0.005% by weight of the transesterification catalyst is added to 100 parts by weight of the aromatic polycarbonate resin and the styrene-based copolymer. Addition is preferable because the compatibility and dispersibility are further improved.

As the transesterification catalyst, zinc acetate, magnesium acetate, antimony oxide, germanium oxide,
Lead monoxide, lead dioxide, tetramethyl titanate, tetraethyl titanate, tetraisopropyl titanate, tetrabutyl titanate, magnesium hexabutoxy hydrogen titanate, potassium titanyl oxalate and the like are exemplified, and among them, tetramethyl titanate, tetraethyl titanate, tetraisopropyl titanate. ,
Tetrabutyl titanate is preferred.

The resin composition of the present invention may contain a heat stabilizer, an antioxidant, a light stabilizer, a lubricant, a plasticizer, an antistatic agent, etc., as long as the characteristics are not significantly impaired. In particular, in order to suppress coloring, it is preferable to add a phosphorus compound such as phosphorous acid, phosphorous acid ester, orthophosphoric acid, orthophosphoric acid ester at the time of melt kneading.

[0026]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be specifically described below with reference to Examples and the like.

The evaluation of the composition was as follows.

(Elongation Evaluation) A dumbbell test piece having a thickness of about 7 mm and a minimum width of about 13 mm was molded from the resin composition by using an injection molding machine (FANUC FAS-50D), and ASTM
It was measured according to D638.

(Evaluation of Peelability) The fracture surface of the sample for elongation evaluation was visually observed, and the presence or absence of peeling was evaluated from the one with the least peeling. ◎: Almost no peeling was observed. ○: Peeling was slight. Intermediate x: Poor peeling was ranked.

The following were used as the aromatic polycarbonate, styrene resin and styrene copolymer.

(1) Aromatic Polycarbonate (PC) As PC, Panlite L1250 manufactured by Teijin Kasei Co. using BisA as an aromatic dihydric phenol was used.

(2) Styrenic Resin (PS) The resin shown in Table 1 was synthesized and used as the PS by the solution polymerization method.

Here, the composition of the copolymer was determined by proton NMR (JEOL GX27) using deuterated chloroform as a solvent.
0), the molecular weight is determined by GPC (Tosoh HLC802
It was calculated in terms of polystyrene from 0).

[0034]

[Table 1]

(3) Styrene Copolymer (Copolymer PS) The resins shown in Table 2 were synthesized and used as the copolymer PS by the solution polymerization method.

The composition and molecular weight were determined in the same manner as PS.

[0037]

[Table 2]

[0038]

[Production Example] Pre-kneading was carried out as follows.

To 40 parts by weight of (MP-1) PC and 60 parts by weight of styrene copolymer CP-1, 0.003 parts by weight of tetraisopropyl titanate as an ester exchange catalyst was added, and a small mixer (Toyo Seiki Labo Plastomill 7) was added.
5C100 / D200E) and kneading at 300 ° C. for 15 minutes,
After taking out, it was cooled and ground. This is abbreviated as MP-1.

(MP2-8) In the same manner as MP-1, a small mixer was used to add tetraisopropyl titanate as a catalyst as needed, and preliminary kneading was carried out. The composition and conditions are shown in Table 3.

The fact that the grafting reaction occurs due to the preliminary kneading and the compatibility is changed is that PC / CP-6 is 50 /
A solution mixture blend sample obtained by uniformly mixing with a chloroform solution in a weight ratio of 50 and reprecipitating in methanol.
The glass transition temperature (Tg) of the pre-kneaded materials MP-5 and MP-6 shown below (DSC Perkin Elmer DS
C7 temperature rise of 20 ° C / min) and change of molecular weight distribution shown in Fig. 1 (GPC chloroform Tosoh HLC802
It is suggested by the example of 0).

PC / CP-6 50/50 solution mixture Tg = 76 ° C. 147 ° C. MP-5 Tg = 76 ° C. 133 ° C. MP-6 Tg = 74 ° C. 126 ° C. (MP-9) Similar to styrene-based copolymer Also for styrene resin SP-2, tetraisopropyl titanate was added using a small mixer and kneaded with PC. The composition and conditions are shown in Table 3.

[0043]

[Table 3]

[0044]

Example 1 75 parts by weight of PC, styrene-based copolymer C
25 parts by weight of P-6 were added to a twin-screw extruder (Werner & Pfleidere
r ZSK25) was kneaded at 270 ° C. to obtain a composition.
As a result of the evaluation, the elongation was 55.4% and the peeling was good.

[0045]

Examples 2 to 4 In the same manner as in Example 1, PC and a styrene-based copolymer were kneaded to obtain a composition and evaluated. The composition and the results are shown in Table 4.

[0046]

Comparative Example 1 For comparison, Table 4 shows the evaluation of elongation of the styrene resin alone.

[0047]

[Comparative Example 2] 50 parts by weight of PC and styrene resin SP-
150 parts by weight were kneaded in the same manner as in Example 1 to obtain a composition. As a result of evaluation, elongation is only 3.5% and peeling is also ×
Met.

[0048]

[Comparative Examples 3 and 4] In the same manner as in Comparative Example 2, PC and styrene resin were kneaded to obtain compositions and evaluated. The composition and the results are shown in Table 4.

[0049]

Examples 5 and 6 MP-5 and MP-3 obtained by kneading PC and a styrene-based copolymer with a small mixer were directly evaluated. The results are shown in Table 4.

[0050]

Comparative Example 5 As in Example 5, MP-9 prepared by kneading PC and styrene resin with a small mixer was evaluated. The results are shown in Table 4.

[0051]

Example 7 80 parts by weight of PC, 20 parts by weight of styrene-based copolymer (styrene-based resin) CP-6, and 10 parts by weight of MP-5 in which PC and styrene-based copolymer were pre-kneaded were twin-screw extruder ( Werner & Pfleiderer ZSK25) was kneaded at 270 ° C to obtain a composition. As a result of evaluation, the elongation was 80.6% and the peeling was ◯.

[0052]

Examples 8 to 18 In the same manner as in Example 7, three were kneaded with PC, a styrene resin (styrene copolymer), and a prekneaded mixture of PC and a styrene copolymer to obtain a composition,
evaluated. The composition and the results are shown in Table 4.

[0053]

[Table 4]

[0054]

EFFECT OF THE INVENTION The composition of the present invention improves the compatibility between the aromatic polycarbonate and the styrenic resin, reduces peeling, and provides a material suitable for applications such as a sheet that retains the ductility of the resin. In particular, it is possible to improve the compatibility more effectively by pre-kneading the aromatic polycarbonate and the styrene-based copolymer having a specific ester group (especially by adding the transesterification catalyst) and then blending the composition. Become.
It is presumed that this is because the pre-kneading promotes the transesterification reaction between the aromatic polycarbonate and the styrene copolymer and contributes as a compatibilizer.

[Brief description of drawings]

FIG. 1 is a molecular weight distribution of a PC / CP-6 (50/50) solution mixture, pre-kneaded products MP-5 and MP-6.

Claims (3)

[Claims] 1. (a) Aromatic polycarbonate resin 20
To 90% by weight, (b) styrene-based resin 0 to 77% by weight, (c) styrene-based monomer 60 to 95% by weight, and one or more kinds of monomers 40 to 5 selected from alkyl acrylate or methacrylic acid alkyl ester. weight%
A resin composition containing 3 to 80% by weight of a styrene copolymer. 2. From (a ′) an aromatic polycarbonate resin and (c) a styrene-based monomer of 60 to 95% by weight, and one or more kinds of monomers selected from an acrylic acid alkyl ester or a methacrylic acid alkyl ester of 40 to 5% by weight. (A '') aromatic polycarbonate resin, (b) after the necessary styrene-based copolymer is melt-kneaded in advance.
Styrene resin is blended, and (a) (= (a ') +
(A '') 20 to 90% by weight of an aromatic polycarbonate resin, (b) 0 to 77% by weight of a styrene resin, and (c) 3 to 80% by weight of a styrene copolymer. 1. The method for producing the resin composition according to 1. 3. From (a ′) aromatic polycarbonate resin and (c) 60 to 95% by weight of a styrene-based monomer, and 40 to 5% by weight of at least one monomer selected from an alkyl acrylate or an alkyl methacrylate. 0.0001 to 0.0 of the transesterification catalyst based on 100 parts by weight of the resin component including the styrene-based copolymer.
After 1 part by weight is added and melt-kneaded in advance, the necessary residual amount of (a ″) aromatic polycarbonate resin and (b) styrene resin are blended, and (a) (= (a ′) + (a ′ '))
20 to 90% by weight of aromatic polycarbonate resin, (b)
The method for producing a resin composition according to claim 1, wherein the styrene resin is 0 to 77% by weight, and the (c) styrene copolymer is 3 to 80% by weight.