JPH02191646A - Thermoplastic resin composition - Google Patents

Abstract

PURPOSE:To provide the resin composition having improved compatibility and further having good heat resistance, moldability, solvent resistance, etc., by comprising an aromatic polycarbonate, a polyolefin and a graft copolymer of a modified polyolefin with a polyester. CONSTITUTION:A resin composition comprises (A) 5-95wt.% of an aromatic polycarbonate, (B) 95-5wt.% of a polyolefin, preferably polypropylene, and (C) 1-30 pts.wt. (based on 100 pts.wt. of the sum of the components A and B) of a graft copolymer comprising C1: 85-15 pts.wt. of a modified polyolefin (preferably glycidyl acrylate-ethylene copolymer) containing 0.2-5mol% of epoxy groups and having a weight-average mol.wt. of 8000-140000 and C2: 15-85 pts.wt. of a polyester, preferably polyethylene terephthalate or polybutylene terephthalate, having an intrinsic viscosity of 0.3-1.2 and an end COOH concentration of 15-200m equivalent/kg.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention contains aromatic polycarbonate and polyolefin as main components, and has properties such as rigidity, impact resistance, heat deformation resistance, moldability, surface peeling resistance, and solvent resistance. The present invention relates to a thermoplastic resin composition with an excellent balance of various properties.

[Conventional technology]

Aromatic polycarbonates have excellent impact resistance, heat resistance, rigidity, and dimensional stability, but have the drawbacks of poor solvent resistance and moldability. In order to obtain a composition with well-balanced mechanical properties while covering these drawbacks,
Various studies have been made regarding blends with polyolefins. However, since the compatibility between polyolefin and polycarbonate is not very good, it has been proposed to add various third components to improve the compatibility.

JP-A-57-108151 discloses polycarbonate resin 1
The patent discloses a polycarbonate resin composition comprising 0.00 parts by weight of polyethylene OJ to 20 parts by weight and 0.3 to 20 parts by weight of butyl rubber. Also, JP-A-57-101
No. 1152 discloses a polycarbonate resin composition containing 0.3 to 20 parts of an ethylene-propylene copolymer and/or an ethylene-propylene-diene copolymer as a third component. Furthermore, JP-A-57-1113
No. 51 discloses a polycarbonate resin composition containing 0.3 to 20 parts of isoprene rubber and/or methylpentene polymer as a third component.

Further, JP-A-61-215649 discloses a composition of at least one high molecular weight aromatic polycarbonate, at least one olefin-vinyl ester copolymer, and an olefin-vinyl alcohol copolymer or polyolefin. are doing. In addition, various compositions made by adding polyester and/or modified polyolefin to aromatic polycarbonate have also been disclosed (Japanese Patent Laid-Open No. 61-22524
No. 5, No. 61-235456, No. 61-238134
No. 7).

[Problem to be solved by the invention]

However, JP-A-57-108151, JP-A No. 57-108151,
i.

In the polycarbonate resin compositions disclosed in No. 8152 and No. 57-111351, the compatibility between polycarbonate and polyethylene is insufficient, so when the amount of polyethylene increases, the impact strength of the molded product not only decreases rapidly. , the problem of surface @ separation also occurred. Furthermore, although the composition disclosed in JP-A No. 61-21.5649 has relatively good solvent resistance, it also has low impact strength due to insufficient compatibility between polycarbonate and polyolefin. There were problems such as surface peeling.

Furthermore, JP-A-61-225245, JP-A No. 61-235
No. 456 and No. 61238847, all of which do not contain polyolefin, have a problem of poor solvent resistance.

In this way, the compatibility between aromatic polycarbonate and polyolefin is improved, and mechanical strength and
Although resin compositions with an excellent balance of moldability and solvent resistance are desired for use in automobile parts, etc., the reality is that a fully satisfactory composition has not yet been obtained.

Therefore, the object of the present invention is to provide a thermoplastic resin composition that has improved compatibility between aromatic polycarbonate and polyolefin, and has a good balance of mechanical strength, heat deformation resistance, moldability, surface peeling resistance, solvent resistance, etc. The goal is to provide the following.

[Means to solve the problem]

As a result of intensive research in view of the above objectives, the present inventors have determined that the compatibility between aromatic polycarbonate and polyolefin can be improved by adding an appropriate amount of a graft copolymer of modified polyolefin and polyester to a composition of aromatic polycarbonate and polyolefin. It was discovered that a composition with excellent balance of mechanical properties, heat deformation resistance, moldability, surface peeling resistance, solvent resistance, etc. can be obtained, and the present invention was conceived based on this discovery.

That is, the thermoplastic resin composition of the present invention comprises (a) 5 to 95% by weight of aromatic polycarbonate, (b) 95 to 5% by weight of polyolefin, and (c) the above (a) aromatic polycarbonate and the above). Based on a total of 100 parts by weight of the polyolefin, a modified polyolefin containing 0.2 to 5 mol% of epoxy groups and a number average molecular weight of 8,000 to 140,000, and a modified polyolefin having an intrinsic viscosity [η] of 0.3 to 1.20 and a carboxyl terminal It is characterized in that it contains 1 to 30 parts by weight of a graft copolymer with polyester having a concentration of 15 to 200 m/11 kg of polyester.

The present invention will be explained in detail below.

The aromatic polycarbonate used in the present invention is (a
) by the reaction of a dihydric phenol with a carbonate precursor such as phosgene in the presence of an acid acceptor and a molecular weight modifier; or (b) by transesterification of a dihydric phenol with a carbonate precursor such as diphenyl carbonate. It can be manufactured by The dihydric phenol that can be used here is preferably bisphenols, particularly 2.
2-bis(4-hydroxyphenyl)propane (bisphenol A) is preferred. Further, part or all of bisphenol may be replaced with other dihydric phenol. Examples of dihydric phenols other than bisphenol A include hydroquinone, 4,4'-dihydroxydiphenyl, bis(4-hydroxyphenyl)alkane, and bis(4-hydroxyphenyl).
-Hydroxyphenyl) cycloalkane, bis(4-hydroxyphenyl) sulfide, bis(4-hydroxyphenyl) sulfone, bis(4-hydroxyphenyl)
Mention may be made of halogenated bisphenols such as sulfoxide, bis(4-hydroxyphenyl)ketone, bis(4-hydroxyphenyl)ether, etc., and bis(3,5-dibromo-4-hydroxyphenyl)propane. Furthermore, a homopolymer using only one of these dihydric phenols 4, a copolymer using two or more types, or a mixture thereof may be used. Such polycarbonate resins can be easily produced by hand as commercially available products. The weight average molecular weight of the aromatic polycarbonate is preferably from 10,000 to 100,000; if it is less than 10,000, the mechanical properties will be insufficient, and if it exceeds 100,000, it will be difficult to mold. A more preferable weight average molecular weight is 20,000 to 50,000.

Polyethylene (high-density polyethylene, low-density polyethylene, linear low-density polyethylene, etc.), polypropylene, polybutene-1, poly4-methylpentene-1 and other α-olefin polymers can be used as the polyolefin, but among them, Preference is given to using polypropylene.

Note that the polyolefin does not need to be a homopolymer, and may be a copolymer with other α-olefins. For example, polypropylene may contain up to 20% by weight of other α-olefins. Other preferred comonomers for propylene copolymers include ethylene. The copolymer may be a random copolymer, a block copolymer, or a graft copolymer. The weight average molecular weight of the polyolefin is preferably 10,000 to 1,000,000, more preferably 30,000 to 300,000.

The graft copolymer used in the present invention is a graft copolymer consisting of a modified polyolefin and a polyester.

The modified polyolefin is a polyolefin obtained by copolymerizing an unsaturated monomer having an epoxy group.

Examples of the unsaturated monomer having an epoxy group include glycidyl methacrylate and glycidyl acrylate.

Examples of the fins to be copolymerized with the unsaturated polymer having an epoxy group include ethylene, propylene, butene-1, pentene-1, and other resins. These olefins can be used alone or in combination of two or more.

Note that monomers such as vinyl acetate, isoprene, chlorobrene, butadiene, etc. may be added to these olefins in an amount of 10% by weight or less, if necessary. Among these modified polyolefins, a copolymer of glycidyl methacrylate and ethylene is particularly preferred.

The epoxy group-containing modified polyolefin may be a block copolymer, a graft copolymer, a random copolymer, or an alternating copolymer.

The weight average molecular weight of the modified polyolefin is 8000~
140,000, and the amount of epoxy groups in the modified polyolefin needs to be 0.2 to 5 mol%. Note that the weight average molecular weight is measured using gel permeation chromatography (GPC) and converted to unmodified polyolefin. Further, the epoxy group content was determined from the analytical value of oxygen element. If the weight average molecular weight is less than 8,000, the effect of improving compatibility will be insufficient, and if it exceeds 140,000, the melt viscosity will increase and moldability will deteriorate. Moreover, if the epoxy group content is less than 0.2 mol %, the reactivity with polyester is low and a graft copolymer is difficult to form. If it exceeds 5 mol%, the reactivity with the polyester becomes too high, the melt viscosity of the reactant increases, and a gel-like substance is produced.

Furthermore, the polyester used in the graft copolymer used in the present invention is generally a thermoplastic resin composed of saturated dicarbonate, M, and saturated dihydric alcohol, such as poly(1-ethylene terephthalate), polypropylene terephthalate,
Examples include polytetramethylene terephthalate (polybutylene terephthalate), polyhexamelene terephthalate, polycyclohexane-1,4-dimethylol terephthalate, polyneopentyl terephthalate, and the like.

Among these, polyethylene terephthalate and poly1-ethylene terephthalate are particularly preferred.

The polyester must have an intrinsic viscosity [vl] of 0.30-1.20 and a terminal carboxyl group concentration of 15-200 m-equivalent z' kg. Here, the intrinsic viscosity [η] (d
Z/g) at 25°C in O-chlorophenol solvent
It was determined from the solution viscosity measured in .

When the intrinsic viscosity [η] of polyester is less than 0°30,
The effect of improving compatibility is insufficient, and when it exceeds 1.20, the melt viscosity of the reactant increases, making it difficult to process. On the other hand, regarding the concentration of terminal carboxylic groups l;i,
15rn equivalent/kg If it is not hot water, the reactivity with the modified polyolefin will be low. Another 200m win! / kg, the curdling property with the modified polyolefin becomes too high and a gel is likely to be formed.

Especially in the case of polyethylene terephthalate, the intrinsic viscosity [η
] is 30-0180, and the terminal carboxyl group concentration is 15-200 m/i! /kg. Intrinsic viscosity [η]
When the ratio exceeds 0.80, the melt viscosity of the graft copolymer becomes high and a gel is formed. The terephthalic acid component in polyethylene terephthalate may be substituted with an r-alkyl group, a halogen group, etc., and the glycol component may be
In addition to ethylene glycol, it may contain up to about 50% of other glycols, such as 1.4-butylene glycol, propylene glycol, hexamethylene glycol, and the like.

In addition, in the case of polybutylene terephthalate, the intrinsic viscosity [
η] is 0.3 to 1°20, and the terminal carboxyl group concentration is 15 to 200 It/kg per m. In this case as well, the terephthalic acid component may be substituted with an alkyl group, a halogen group, etc., and the glycol component may be one substituted with an alkyl group, a halogen group, etc.
．． In addition to 4-butylene glycol, it may contain other glycols such as ethylene glycol, butylene glycol, hexamethylene glycol, etc. up to about 50% by weight.

In order to graft-polymerize the above-mentioned polyester and modified polyolefin, after tri-blending them,
Melt kneading at ~320°C for 0.5-15 minutes.

Melt-kneading is preferably carried out in an extruder, particularly in a twin-screw extruder. If the reaction temperature is less than 260°C, grafting will not be sufficient, and if it exceeds 320°C, a rapid reaction will occur, resulting in clogging of the extruder due to gel formation. Moreover, deterioration of the polyolefin occurs.

The amount of polyester and modified polyolefin is 15 to 85 parts by weight for the former K, and 85 to 15 parts by weight for the latter.
Parts by weight. Polyester is less than 15 parts by weight or 8
If the amount is more than 5 parts by weight, the amount of graft copolymer produced will decrease.

The polyolefin-polyester graft copolymer thus obtained is used as a compatibilizer for polycarbonate resin and polyolefin.

In the present invention, the blending ratio of polyolefin and aromatic polycarbonate is 95-5% by weight to 5-95% by weight. When aromatic polycarbonate is less than 51%,
Sufficient impact resistance and strength cannot be obtained, and if it exceeds 95% by weight, moldability and solvent resistance decrease.

The content of the graft copolymer is 1 to 3 parts based on the total weight of aromatic polycarbonate and polyolefin.
It is 0 parts by weight. If it is less than 1 part by weight, no effect on the compatibility between aromatic polycarbonate and polyolefin can be obtained by adding the graft copolymer, and if it exceeds 30 parts by weight, mechanical properties such as impact resistance may deteriorate. descend. The preferred graft copolymer content is 1 to IO parts by weight.

The thermoplastic resin composition of the present invention further includes a rubber component such as a low-crystalline ethylene-α-olefin copolymer, an acrylic elastomer, and a butyl rubber in order to improve impact resistance. It may be contained in an amount of 100 parts by weight or less.

In addition, for the purpose of modifying the thermoplastic resin composition of the present invention, other additives such as reinforcing materials such as glass fibers and carbon fibers, inorganic fillers, heat stabilizers, antioxidants, light Stabilizers, flame retardants, plasticizers, antistatic agents, mold release agents,
A blowing agent, a nucleating agent, etc. can be added.

The thermoplastic resin composition of the present invention can be produced using a -screw extruder, a twin-screw extruder, a Banbury mixer-1 kneading roll, a Brabender
It is obtained by kneading in a heated molten state using a kneader such as a kneader or a mixer such as a Henschel mixer.

[For production]

Compatibility between aromatic polycarbonate and polyolefin is poor, but compatibility between polyolefin and modified polyolefin is good, and aromatic polycarbonate and polyester are made compatible by transesterification during kneading.

Therefore, when a graft copolymer of a modified polyolefin and a polyester is mixed and kneaded with a composition of an aromatic polycarbonate and a polyolefin, the graft copolymer selectively coordinates to the interface between the aromatic polycarbonate and the polyolefin, and the aromatic Good compatibilization between polycarbonate and polyolefin results. As a result, mechanical properties,
Heat deformation resistance, moldability, surface peeling resistance, solvent resistance, etc.
It is believed that a thermoplastic resin composition with good lance can be obtained.

〔Example〕

The present invention will be explained in further detail by the following examples.

In each Example and Comparative Example, physical property values were measured as follows.

(1) Heat deformation temperature - When the temperature is raised at a constant rate (2℃/min), the test piece (simple sliver) is subjected to a constant load (4.6kg/min).
Measure the temperature when it bends by a predetermined amount (0.25m) in accordance with JIS K7207.

(2) Dynamic melt viscosity = 280°C, 10 Orad by dynamic spectrometer manufactured by Rheometrics
Measured at /sec.

(8) Solvent resistance (heavy change due to immersion in methanol) - The molded product was immersed in methanol at 25°C for 30 days, and the change in weight was measured.

(4) Surface peeling resistance = 100 squares of 1 srs x 1 ram were formed on the surface of the test piece using a razor, and after adhering cellophane tape to the squares, it was peeled off. Among the 100 squares, the number of squares that did not adhere to the cellophane tape and remained on the surface of the test piece was counted.

Examples 1 to 5 Bondfast E (manufactured by Sumima Kagaku Kogyo ■, weight average molecular 173000, epoxy group content 2.7 mol%) was used as the modified polyolefin, and C700ON (manufactured by Teijin Masu [η] = 1) was used as the polybutylene terephthalate. .05
(measured at 25°C in o-chlorophenol solvent) and terminal carboxyl group concentration = 46 m equivalents/kg) were used. C
700ON is sufficiently pre-dried in advance to remove moisture and bonded.) E: C700ON= 30
: Tri-blended at a weight ratio of To, and melt-kneaded using a twin-screw extruder at 280°C for a residence time of about 1 minute.

As a result of isolating m-cresol (100°C) insoluble matter and xylene (100°C) insoluble matter from the graft-reacted product by melt-kneading under the above conditions, the 42°7
It was confirmed that % by weight was a graft copolymer.

Second, polypropylene pellets (Tonen Petrochemical Q@ J 209. MFR = 9 g/10 min), aromatic polycarbonate (Teijin Kasei Panlite L 1225,
(weight average molecular weight: 22.500) and the graft copolymer were triblended in the proportions shown in Table 1 below, and a thermoplastic resin composition pellet was produced at 280° C. using a twin-screw kneader. Test pieces were prepared from each of the obtained thermoplastic resin composition pellets by injection molding (270° C.), and the heat distortion temperature, dynamic melt viscosity, solvent resistance, and surface peeling resistance were measured.

The results are also shown in Table 1.

Example 6 Instead of polybutylene terephthalate in Example 1, TR8550 (Teijin ■) was used as polyethylene terephthalate.
[η] = 0.75 (measured at 25°C in o-chlorophenol solvent) and terminal carboxyl group concentration = 26 m
The grafting reaction was carried out by melt-kneading in the same manner as in Example 1, except that the amount (equivalent/kg) was used.

When the obtained product was analyzed in the same manner as in Example 1, 16.7% by weight of the product was found to be a graft copolymer.

Next, polypropylene pellets (J209>), aromatic polycarbonate (Panlite L1225), and the graft copolymer were triblended in the proportions shown in Table 1 below, and a test piece was prepared in the same manner as in Example 1. A similar test was conducted.

The results are shown in Table 1.

Comparative Example 1 The physical properties of polypropylene (J209) alone (100% by weight) were measured in the same manner as in Example 1.

The results are shown in Table 2.

Comparative Example 2 Aromatic polycarbonate (Panlite L1225)
Physical properties were measured in the same manner as in Example 1 for the case of using only one (100% by weight). The results are shown in Table 2.

Comparative Examples 3 to 5 Thermoplastic resin compositions were prepared in the same manner as in Example 1, except that a two-component system of polypropylene (J209) and aromatic polycarbonate (Panlite L1225) was used, and the physical properties were measured. The results are shown in Table 2.

As is clear from the results in Tables 1 and 2, the thermoplastic resin composition of the present invention has a higher resistance to heat deformation (expressed by heat distortion temperature) than a thermoplastic resin composition that does not contain a graft copolymer. It can be seen that the composition has a good balance of moldability (expressed by dynamic melt viscosity), surface peeling resistance, and solvent resistance.

〔Effect of the invention〕

As mentioned above, in the thermoplastic resin composition of the present invention, a graft copolymer of modified polyolefin and polyester is added to aromatic polycarbonate and polyolefin, so the compatibility between aromatic polycarbonate and polyolefin is significantly improved. heat resistance, moldability, surface peeling resistance,
Good balance of solvent resistance etc. Furthermore, it has excellent impact resistance and mechanical strength. The thermoplastic resin composition of the present invention can be suitably used as an engineering plastic material, particularly for automobile parts.

Claims (1)

[Scope of Claims] (1) (a) 5 to 95% by weight of aromatic polycarbonate, (b) 95 to 5% by weight of polyolefin, (c) said (a) aromatic polycarbonate and said (b)
0.2 to 100 parts by weight of polyolefin in total
Contains 5 mol% of epoxy groups and has a weight average molecular weight of 8000
~140,000 modified polyolefin and intrinsic viscosity [η
] is 0.30 to 1.20 and the concentration of terminal carboxyl groups is 15 to 200 m equivalent/kg. 1 to 30 parts by weight of a graft copolymer with a polyester. 2. The thermoplastic resin composition according to claim 1, wherein the polyester has an intrinsic viscosity [η] of 0.30 to 0.8.
0 and the concentration of terminal carboxyl group is 15 to 200 m equivalent/
kg of polyethylene terephthalate and/or polybutylene terephthalate having an intrinsic viscosity [η] of 0.30 to 1.20 and a terminal carboxyl group concentration of 15 to 200 m equivalent/kg. (3) In the thermoplastic resin composition according to claim 1,
A thermoplastic resin composition, wherein the polyolefin is polypropylene.