JP3210755B2 - Thermoplastic resin composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to impact resistance, chemical resistance,
The present invention relates to a thermoplastic resin composition having excellent heat resistance and hot water resistance.

[0002]

2. Description of the Related Art Aromatic polyesters have excellent heat resistance and electrical properties, and include electrical and electronic components such as switch covers, computer housings, power tool housings, headlamps, bumper faces, front skirts, and engines. Control device cases,
It is widely used in automobile parts such as valve covers and food containers such as trays. On the other hand, styrene-based polymers are used for various applications because of their excellent workability. Aromatic polyesters are highly dependent on mechanical properties, particularly impact strength in thickness, are inferior in moldability and are expensive. Therefore, in order to improve the impact strength, a composition comprising an aromatic polyester and a polystyrene resin has been proposed (Japanese Patent Publication No. 46-5229). However, even in these compositions, sacrificing heat resistance in order to satisfy molding processability, chemical resistance of molded products, hot water resistance,
There is a disadvantage that the balance of physical properties such as impact resistance is poor. Further, it has been proposed to add an epoxy-modified polyolefin or an epoxy-modified polystyrene to these compositions (Japanese Patent Application Laid-Open No. 01-263149, Japanese Patent Publication No. 03-57942), but these are satisfactory from the viewpoint of impact resistance. The fact is that is not obtained.

[0003]

SUMMARY OF THE INVENTION The present inventors have made intensive studies to improve the impact strength, hot water resistance and chemical resistance of molded articles without sacrificing the excellent heat resistance of aromatic polyesters. As a result, the present invention has been achieved.

[0004]

That SUMMARY OF THE INVENTION The present invention comprises an aromatic polyester (A) and the styrenic resin (B), aromatic polycarbonate (C), and polycaprolactone (D), aromatic polyester ( A) and style
The mixing ratio with the resin (B) is (A)
10 to 90 parts by weight per 100 parts by weight of (B), 9
0 to 10 parts by weight, aromatic polycarbonate (C)
Per 100 parts by weight of the total of (A) and (B)
0.5 to 20 parts by weight, polycaprolactone (D)
Is 100 parts by weight in total of (A) and (B).
In addition, the present invention provides a thermoplastic resin composition having excellent impact strength, hot water resistance, chemical resistance, and heat resistance, which is 0.2 to 20 parts by weight .

The aromatic polyester used in the present invention includes polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polytrimethylene terephthalate, polyhexamethylene terephthalate,
Poly 1,4-cyclohexylene dimethylene terephthalate, polyethylene terephthalate-isophthalate copolymer, poly 1,4-cyclohexylene dimethylene terephthalate-isophthalate copolymer, polyethylene
2,6-naphthalate, polytetramethylene-2,6-
Naphthalate and the like can be mentioned, and one or more of these can be used. Of these, PET and PB
T is preferred, and PBT is particularly preferred.

The styrene resin (B) used in the present invention is a polymer containing an aromatic vinyl compound such as styrene, α-methylstyrene, p-methylstyrene and chlorostyrene as essential components. A homopolymer of a compound, a copolymer of an aromatic vinyl compound and another copolymerizable compound, and a copolymer of an aromatic vinyl compound alone or another copolymerizable compound in the presence of a rubbery polymer. It is a graft copolymer obtained by polymerization, or a mixture of these styrene polymers. Other copolymerizable compounds constituting the above copolymer or graft polymer include unsaturated nitrile compounds such as acrylonitrile and methacrylonitrile, methyl (meth) acrylate, and ethyl (meth).
Acrylates, unsaturated carboxylic acid alkyl esters such as butyl (meth) acrylate, acrylic acid, methacrylic acid, maleic acid, maleic anhydride, unsaturated carboxylic acid such as citraconic anhydride, or unsaturated dicarboxylic anhydride, maleimide, Maleimide compounds such as methylmaleimide, ethylmaleimide, N-phenylmaleimide, and O-chloro-N-phenylmaleimide are exemplified. More specific examples of the copolymer include the following various copolymers. Styrene-acrylonitrile copolymer, α
-Methylstyrene-acrylonitrile copolymer, styrene-methyl methacrylate copolymer, α-methylstyrene-acrylonitrile-methyl methacrylate copolymer,
Styrene-maleic anhydride copolymer, styrene-maleic anhydride-acrylonitrile copolymer, styrene-maleimide copolymer, styrene-N-phenylmaleimide copolymer, styrene-acrylonitrile-N-phenylmaleimide copolymer, etc. is there. Examples of the rubbery polymer constituting the graft copolymer include polybutadiene, styrene-butadiene copolymer, diene-based copolymer such as acrylonitrile-butadiene copolymer, and ethylene-propylene-non-conjugated diene copolymer. Examples include ethylene-propylene copolymers, chlorinated polyethylene, acrylic rubbers represented by polybutyl acrylate, and ethylene-vinyl acetate copolymers. More specifically, examples of the graft copolymer include the following various graft copolymers. Diene rubber-styrene copolymer, acrylonitrile-diene rubber-styrene copolymer, methyl methacrylate-diene rubber-styrene copolymer, acrylonitrile-ethylene-propylene rubber-styrene polymer,
Acrylonitrile-acrylic rubber-styrene copolymer; acrylonitrile-chlorinated polyethylene-styrene polymer; styrene-diene rubber-maleic anhydride copolymer. In the present invention, in consideration of not only chemical resistance, impact resistance, hot water resistance, thermal stability, but also the balance between processability and impact resistance, particularly as the styrene-based polymer, the above-mentioned graft polymer or graft It is preferred to use a mixture of the polymer with another homopolymer or copolymer. These styrenic polymers can be produced by bulk polymerization, solution polymerization, suspension polymerization, emulsion polymerization, or a combination thereof.

The polycaprolactone in the present invention is produced by a known polymerization method and can be obtained, for example, as follows. That is, when ε-caprolactone is polymerized into polycaprolactone, water or a compound having hydroxyl groups at both ends is used as the polymerization initiator,
The catalyst can be obtained by polymerization using an organic tin compound, an organic titanium compound or the like.

The aromatic polycarbonate used in the present invention is a polymer obtained by a phosgene method of reacting various dihydroxydiaryl compounds with phosgene, or a transesterification method of reacting a dihydroxydiaryl compound with a carbonate such as diphenyl carbonate. It is a copolymer, and a typical one is a polycarbonate resin produced from bisphenol A. The molecular weight of the aromatic polycarbonate resin is required to be 15,000 or more in terms of viscosity average molecular weight, preferably 200
00 to 30,000. If it is less than 15,000, there is a problem in practical strength such as impact strength, and if it has a molecular weight of 30,000 or more, fluidity is impaired.

The composition ratio of the aromatic polyester (A) and the styrene resin (B), the aromatic polycarbonate (C) and the polycaprolactone (D) is not particularly limited, but the chemical resistance, hot water resistance and impact resistance (A) and (B) are 10 to 90 parts by weight and 90 parts by weight, respectively, per 100 parts by weight of the total amount of the aromatic polyester (A) and the styrene-based resin (B) from the viewpoint of the balance of physical properties such as properties and processability. -10
It is preferable that the amount of each of the components (C) and (D) is 0.5 to 20 parts by weight. When the styrene resin as the component (B) is less than 10 parts by weight, the characteristics of the styrene resin such as good moldability and good surface gloss are sacrificed in the final product. If the amount exceeds 90 parts by weight, the chemical resistance and heat resistance of the final product are sacrificed. The amount of the aromatic polycarbonate to be added is 0.5 to 20 parts by weight based on 100 parts by weight of the total of (A) and (B).
If the amount is less than 5 parts by weight, the affinity between the component (A) and the component (B) is slightly improved, which may cause delamination. Also, 20
Addition exceeding part by weight is not preferable in terms of cost. If the amount of polycaprolactone is less than 0.5 parts by weight, no improvement in chemical resistance can be expected, no improvement in impact strength can be expected, and phase separation occurs in molded products. If it exceeds 20 parts by weight, the hot water resistance is greatly reduced due to the high degradability of polycaprolactone.

The mixing of the aromatic polyester (A), the styrene polymer (B), the aromatic polycarbonate (C) and the polycaprolactone (D) can be performed by a known method such as a Banbury mixer, a single screw extruder or a twin screw extruder. It can be performed using a mixer. Examples of the mixing method include a batch mixing method in which three components are simultaneously mixed and a two-stage mixing method in which arbitrary two components are mixed and then a third component is mixed. In addition, at the time of mixing, an antioxidant, an ultraviolet absorber, an antistatic agent, a lubricant, a dye or pigment, and a reinforcing agent such as glass fiber, metal fiber, or carbon fiber can be appropriately compounded.

[0011]

The present invention will be described below with reference to examples, but the present invention is not limited to these examples.

Examples 1 to 4 and Comparative Examples 1 to 5 Polybutylene terephthalate (PBT) (Duranex 400 FP, 700 FP manufactured by Polyplastics) as an aromatic polyester (A) and diene rubber reinforced as a styrene resin (B) Polystyrene (HIPS)
(Sumitomo Chemical's Esgrite 500HG-S), aromatic polycarbonate (PC) (Mitsubishi Gas Chemical's Iupilon S1000), and polycaprolactone (PCL) (Placcel H7 manufactured by Daicel Chemical Industries, Ltd.) in a mixing ratio shown in Table 1. And melt-kneaded in a Banbury mixer to form pellets. The pellets were injection molded to form various test pieces and evaluated. The results are shown in Table 1.

The evaluation methods of the physical properties are as follows. (1) Izod impact resistance Sample thickness 3.2 mm, measuring temperature 23 ° C., with mold notch, conforming to JIS K7110. (2) Thermal deformation temperature Sample thickness 3.2 mm, bending stress 4.6 kgf / cm
² . Conforms to JIS K7207. (3) Elongation at break Complies with ASTM D-638. (4) Oil resistance test Margarine was applied to a strand sample of about 3 mm under a load of 1000 psi. The time until the strand broke was measured. Units (minutes).

[0014]

[Table 1]

[0015]

As is clear from the examples and comparative examples, the composition of the present invention exhibits higher heat resistance and impact resistance than conventional styrene resins, and thus, the conventional heat resistance and impact resistance are insufficient. Therefore, it can be applied to applications where application was difficult.

Claims (2)

(57) [Claims] 1. A aromatic polyester (A), made of styrene-based resin (B), aromatic polycarbonate (C), and polycaprolactone (D), aromatic Poriesu
The mixing ratio of tellurium (A) and styrene resin (B) is
10 to 10 parts by weight of the total of (A) and (B)
90 parts by weight, 90 to 10 parts by weight, aromatic polycarbonate
When the blending ratio of the carbonate (C) is 10 in total of (A) and (B)
0.5 to 20 parts by weight per 0 parts by weight;
The mixing ratio of lactone (D) is 10 in total of (A) and (B)
0.2 to 20 parts by weight per 0 parts by weight of the thermoplastic resin composition. 2. The method according to claim 1, wherein the aromatic polyester (A) is a polyether.
Tylene terephthalate, polybutylene terephthalate,
Polytrimethylene terephthalate, polyhexamethylene
Terephthalate, poly 1,4-cyclohexylene dimethyl
Renterephthalate, polyethylene terephthalate-a
Sophthalate copolymer, poly 1,4-cyclohexylene
Dimethylene terephthalate-isophthalate copolymer,
Polyethylene-2,6-naphthalate, polytetramethyl
A material selected from len-2,6-naphthalate
The thermoplastic resin composition according to claim 1.