JPH05156141A - Molded polyester article and its preparation - Google Patents

Abstract

PURPOSE:To prepare the subject article having a network structure formed by two resins penetrated into each other by adding acrylic graft (co)polymer particles under specified conditions to the two resins, a polyalkylene terephthalate resin as a matrix and a polycarbonate resin, when the resins are melt mixed with each other. CONSTITUTION:A polyalkylene terephthalate resin as a matrix and a polycarbonate resin in a wt. ratio of the former to the latter resin of (95:5) to (55:45) are mixed by melting to together with acrylic graft (co)polymer particles which have a mean particle diameter of 10mum or lower and do not flow at the melt mixing temp., the amt. of the particles being 0.5-30wt.% based on the sum of the three components.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a polymer mixture in which a polycarbonate resin is blended with a polyalkylene terephthalate resin, and the dispersion state is different from usual granular dispersion, and these two resin components are mutually The present invention provides a molded polyester product having excellent mechanical properties and other physical properties with respect to a method for manufacturing a molded product having a meshed structure formed by penetrating into the inside.

[Conventional technology and its problems]

 Thermoplastic polyalkylene terephthalate resins, typified by polybutylene terephthalate, have excellent crystallinity, are easy to obtain good molded products in high cycles, have extremely low water absorption, have good dimensional accuracy, chemical resistance, and electrical resistance. It has excellent properties, and its properties are dramatically improved by reinforced glass fiber, and its applications are expanding rapidly. However, the impact strength is insufficient due to the good crystal characteristics, and the glass fiber reinforced product has a problem that warpage of the molded product is likely to occur and the surface gloss decreases. Moreover, since the glass transition temperature is low, the rigidity at high temperatures is insufficient as compared with polyacetal resins and the like. Polymer alloys have been extensively studied to cover these practical drawbacks, and many combinations have been studied.

 As one example, polycarbonate resin has a high glass transition temperature and high impact resistance.Therefore, it can be expected that modification by utilizing this property can be expected by compounding it, and many studies have been made and commercialized. Has been done. However, an alloy of a pure polyalkylene terephthalate resin and a polycarbonate resin has a limited effect on the above improvement, and a higher degree of improvement is often required.

[Means for Solving the Problems]

 As a result of repeated studies, the present inventors have focused on the dispersion morphology of a polyalkylene terephthalate resin (A) blended with a polycarbonate resin (B), and as a result, in general, both components are so-called sea-islands. It has a structure, especially when the polycarbonate component (B) is in a small amount, it has a structure in which it is separated into particles (as islands) and dispersed, whereas by mixing with a specific granular additive and melt-kneading. Therefore, it was discovered that even when the polycarbonate component (B) was in a small amount, not only ordinary granular dispersion but both components (A) and (B) formed a three-dimensional network structure in which they were entangled with each other. The present inventors have found that a molded product having excellent mechanical properties can be obtained by forming a dispersed structure, and have reached the present invention.

 That is, according to the present invention, when the polycarbonate resin (B) is melt-kneaded and blended with the polyalkylene terephthalate resin (A), an acrylic-based graphite (with an average particle size of 10 μm or less, which does not flow at the melt-kneading temperature ( Co) polymer particles (C) are added in a blending amount satisfying the following formulas (1) and (2) and melt-kneaded, and the components (A) and (B) are substantially mutual. The present invention relates to a molded product that has penetrated into the inside to form a network structure and a manufacturing method thereof.

 Formula (1) B / (A + B) = 0.05 to 0.50 (weight ratio) Formula (2) C / (A + B + C) = 0.005 to 0.30 (weight ratio) Components (A) and (B) in the molded article obtained by the present invention Explaining the dispersion morphology of Fig. 1, Fig. 1 schematically shows the dispersion morphology when the polyalkylene terephthalate (A) and the polycarbonate (B) are melt-kneaded as in the conventional case. Compared with the polyalkylene terephthalate (A). Polycarbonate (B) with a small blending amount shows a form dispersed in a particulate form. On the other hand, FIG. 2 schematically shows the dispersed morphology of the present invention. Unlike the case of FIG. 1, in this structure, the matrix resin (A ) And at least part of the effective amount of the polycarbonate (B) generally form a network together in large part and form an entangled structure to form a substantially continuous phase. The scattered structure is called the interpenetrating network structure).

 Such a dispersed structure can be confirmed by observing the cross section of the molded body with an optical microscope or an electron microscope. Alternatively, it can be determined by appropriately crushing or cutting the molded piece, immersing the molded piece in a trichloroethane solution at room temperature under ultrasonic oscillation to elute the polycarbonate (B), and measuring the weight reduction rate. If the polycarbonate (B) is a conventional particle dispersion, the solvent treatment causes almost no contact with the solvent, and the weight loss due to elution hardly occurs. On the other hand, when the polycarbonate resin (B) has an interpenetrating network structure with the polyalkylene terephthalate resin (A) as in the present invention, the polycarbonate resin (which is continuous from the molded product surface and the cut surface ( Since B) elutes, it can be seen that the greater the weight loss, the more the interpenetrating network structure is formed.

 The present invention forms such an interpenetrating network structure by adding a specific acrylic graft (co) polymer at the time of melt-kneading a polycarbonate (B) to a polyalkylene terephthalate (A), thereby significantly improving physical properties. This is a characteristic of the present invention, which is completely unexpected from the prior art.

 The present invention is described in detail below.

 First, the polyalkylene terephthalate resin (A) used in the present invention is a polyester containing polyethylene terephthalate and polybutylene terephthalate, especially polybutylene terephthalate as a main component, and one of the terephthalic acid component or butanediol component thereof. It may be a copolymer in which one part is replaced with another copolymerization component.

 As the copolymerization component, a bifunctional dicarboxylic acid such as phthalic acid, isophthalic acid, naphthalenedicarboxylic acid, diphenoxyethanedicarboxylic acid, adipic acid or sebacic acid, or benzentricarboxylic acid as a branching component may be used.

 Examples of the diol component forming the copolymer include ethylene glycol, propanediol, hexanediol, polyoxyethylene glycol, polyoxypropylene glycol, polyoxytetramethylene glycol and other polyoxyalkylene glycols, and further bisphenol. A, bisphenol F or alkylene oxide 2 mol adduct of these bisphenols and the like can be mentioned. As the branching component, a trifunctional or higher functional alcohol may be used in place of part of the diol component. Of course, two or more kinds of these polyalkylene terephthalates may be mixed.

 Next, the polycarbonate resin (B) used in the present invention is not particularly limited, but a main repeating unit is preferably represented by the following general formula (3).

(In the formula, Q represents a divalent organic radical. R represents an alkyl group or halogen, m and n each represent an integer of 0 to 4.) The divalent organic radical represented by Q is, for example, an oxy group. , A sulfonyl group, a carbonyl group, a methylene group, a dichloromethylene group, an ethylidene group, a butylidene group, a 2,2-propylidene group, a 1,1-phenethylidene group, a phenylenebis (2,2-propylidene) group and the like. R is an alkyl group such as a methyl group, an ethyl group, a propyl group or a butyl group, or a halogen. Further, m and n are integers of 0 (only hydrogen) to 4, respectively.

 Next, the acrylic graft (co) polymer particles (C) having an important role in the formation of the interpenetrating network structure of the present invention means that the average particle size is 10 μm or less, and the components (A) and (B) are It is a substance with a high melting point that does not show fluidity at the melt-kneading temperature.

 If the average particle size is coarser than 10 μm, it is difficult for the molded product to form a mesh, and the effect of improving the physical properties cannot be obtained. The preferred particle size is 5 μm or less, and particularly preferably 1 μm or less.

 Further, it is important that the acrylic graft (co) polymer particles (C) remain in the particulate state and do not flow at the melt-kneading temperature. From this viewpoint, the melting point of (C) is at least (A) and (B). It is higher than the melt-kneading temperature of the components, and generally, the melt-kneading temperature of the components (A) and (B) is appropriate to be 230 to 280 ° C. Temperature is desirable. Such physical properties are adjusted by the graft ratio or the degree of crosslinking of the acrylic graft (co) polymer. If the component (C) easily flows at the melt-kneading temperature, it becomes difficult to form the above-mentioned network structure, and the effect of improving the physical properties cannot be obtained.

 The above-mentioned acrylic graft (co) polymer (C) used in the present invention comprises an acrylic acid alkyl ester or methacrylic acid alkyl ester as a main monomer, and is polymerized by adding a crosslinking agent and / or a graft crossing agent. Obtained by the method described above, a part of the alkyl acrylate may be replaced with another vinyl monomer. Examples of vinyl monomers include styrene-based monomers and acrylonitrile. Alternatively, a multi-layer polymer obtained by dividing the polymerization into multi-stages and adding monomers (acrylic acid alkyl ester or other vinyl monomer) and a cross-linking agent and the like stepwise at each stage, but finally it is an acrylic type It is important that the graft (co) polymer does not flow during melt-kneading. The polymerization method is not particularly limited, but the emulsion polymerization method is preferable in that a fine particle size can be obtained.

 The ratio of the polyalkylene terephthalate resin (A) to the polycarbonate resin (B) in the polymer alloy of the present invention is preferably 95 to 50 parts by weight for (A) and 5 to 50 parts by weight for (B), and more preferably A ratio of 90 to 70 parts by weight of (A) and 10 to 30 parts by weight of (B) is preferable. When the content of the polycarbonate resin (B) exceeds 50 parts by weight, excellent properties such as chemical resistance of the polyester resin are lost, which is not preferable. Further, if the content of the polycarbonate resin is less than 5 parts by weight, the formation of the interpenetrating network structure will be insufficient even if the component (C) is added, and the effect of improving the physical properties will be reduced.

 Further, the addition amount of the acrylic graft (co) polymer particles (C) can be appropriately increased or decreased, but in general, various physical properties are taken into consideration, and the polyalkylene terephthalate resin and the polycarbonate resin have an interpenetrating network structure. In order to form a body, it is 0.5 to 30% by weight, preferably 1 to 20% by weight, based on the total amount of (A), (B) and (C). If the amount of the component (C) is too small, it becomes difficult to form a network structure, and if it is too large, other general physical properties and the surface condition of the molded article are hindered, which is not preferable.

 The molded product having an interpenetrating network structure of the present invention can be easily prepared by blending the above-mentioned components (A), (B) and (C) by a usual melt-kneading method. For example, it is formed by melt-kneading and extruding at 230 to 280 ° C using a single-screw or multi-screw extruder, and even when it is a molded product by injection molding, blow molding, etc., its network structure is maintained and its physical properties are remarkable. The same effect can be obtained even when the film or sheet is produced by a commonly used film forming method such as an inflation method or a T-die method.

 The molded product of the present invention may be used in combination with commonly used fibrous, granular, or plate-like inorganic fillers as long as it does not impair the object, and it may be supplemented with another thermoplastic resin. You may mix a small amount.

Further, in order to impart desired properties, conventionally known additives such as antioxidants, heat stabilizers, stabilizers such as weather-resistant (light) stabilizers, lubricants, nucleating agents, release agents, dyes and pigments, etc. You may mix | blend the coloring agent of this.

〔Example〕

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

Examples 1 to 6 (A) Polybutylene terephthalate (PBT) [Intrinsic viscosity 0.8] (B) Polycarbonate (PC) [Mitsubishi Gas Chemical Co., Ltd. Iupilon S-3000] (C) Styrene Acrylic graft copolymer containing (average particle size is shown in Table 1, does not flow at 260 ° C) was blended and then melted at 250 ° C using a twin screw extruder with 40 mmφ and L / D = 36. Pellets were prepared by kneading and extruding.

 The pellets were cut, the cross section was observed with a microscope, and the pellets were crushed and the dissolution test of the component (B) was performed with trichloroethane to check the dispersion morphology (in the case of granular dispersion, the component (B) was eluted. Difficult to do and little weight loss).

 Then, the pellets were injection molded at a resin temperature of 250 ° C to prepare various test pieces, and the notched Izod impact strength (conforming to ASTM D-256), tensile strength, and tensile elongation (conforming to ASTM D-638). ) Was measured.

 The results are shown in Table 1.

Comparative Examples 1 to 6 (A) PBT alone, (A) PBT and (B) PC alone, and acrylic graft copolymer having a particle size outside the range of the present invention as the component (C) (bulk polymer pulverized The same test as in Examples 1 to 6 was carried out for a material containing an acrylic polymer (small graft ratio) that melts and flows at a kneading temperature (250 ° C.).

The results are also shown in Table 1.

Examples 7 to 9 (A) Polybutylene terephthalate (PBT) [Intrinsic viscosity 1.4] (B) Polycarbonate (PC) [Mitsubishi Ion Chemical Co., Ltd. Iupilon S-3000] (C) Acrylic The system-based graft polymer (average particle size is shown in Table 2 and does not flow at 260 ° C.) was melt-kneaded in the same manner as in Examples 1 to 6 to prepare pellets, and the dispersion morphology was examined.

 Then, using an inflation film-forming machine equipped with a 20 mmφ single-screw extruder and an annular die (die diameter of 25 mm), the pellets were made into an inflation film with a film temperature of 250 ° C and a blow ratio of 1.8, and a film thickness of about 30 mm. did. For this film, the Elmendorf tear strength in both the vertical and horizontal directions was measured according to ASTM D1922, and the impact strength was measured using a dirt impact tester according to ASTM D-1709.

 The results are shown in Table 2 (however, the tear strength is an average value in both the vertical and horizontal directions).

 An electron micrograph showing the particle structure (dispersion morphology) of the components (A) and (B) in the film of Example 7 (cross section parallel to the tensile direction) is shown in FIG.

Comparative Examples 7 to 10 (A) PBT alone, (A) PBT and (B) PC only, and those in which the particle diameter of the acrylic graft polymer as the component (C) is outside the range of the present invention (agglomerated polymer powder) ), An inflation film was prepared in the same manner as in Examples 7 to 9 using an acrylic polymer (small graft ratio) that melts and flows at the kneading temperature (250 ° C.), and the same test is performed. went.

 The results are also shown in Table 2.

 An electron micrograph showing the particle structure (dispersion morphology) in the film of Comparative Example 8 (cross section parallel to the tensile direction) is shown in FIG.

4 and 3 show the particle structure after the component (B) was eluted and removed by the above-mentioned method on the cross section parallel to the tensile direction of the film (the component (B) became a cavity). Comparative Example 8 (FIG. 3) shows a simple particle structure (extended by tension), whereas Example 7 (FIG. 4) has a complicated morphology because it is entangled in a mesh shape. It can be seen that

Examples 10 to 13 (A) PBT copolymer (containing 12.5 mol% of isophthalic acid and an intrinsic viscosity of 1.2) in the compounding amounts shown in Table 3 (B) Polycarbonate (PC) [Mitsubishi Ichigo Chemical Co., Ltd. Iupilon H-3000] ] (C) Styrene-containing acrylic graft copolymer (average particle size is shown in Table 3, does not flow at 260 ° C) was melt-kneaded in the same manner as in Examples 1 to 6 to prepare pellets and dispersed. The morphology was examined.

 Next, the pellets were extruded into a film at a resin temperature of about 250 ° C. using a film forming machine equipped with a T-die to form a film having a film thickness of about 45 μm, and the same tests as in Examples 7 to 9 were conducted.

 The results are shown in Table 3.

Comparative Examples 11 to 14 (A) PBT alone, (A) PBT and (B) PC only, and the acrylic graft polymer as the component (C) has a particle size outside the range of the present invention (agglomerated polymer powder) ), Using an acrylic polymer (small graft ratio) that melts and flows at the kneading temperature (250 ° C.), a T-die film was prepared in the same manner as in Examples 10 to 13, and the same test was conducted. It was

The results are also shown in Table 3.

〔The invention's effect〕

 As is clear from the above description and Examples, according to the method of the present invention, a molded article having a network structure in which polycarbonates are intertwined with each other in polyalkylene terephthalate is obtained, and in the conventional dispersion form. It is possible to obtain high-level improvements in mechanical properties that cannot be obtained, especially impact strength and toughness. Moreover, it is possible to significantly improve tear strength and impact strength as a film or sheet, and it is expected that the applications will be expanded.

[Brief description of drawings]

 FIG. 1 is a schematic view showing a dispersion form by a conventional method, and FIG. 2 is a schematic view showing a dispersion form by the method of the present invention. FIG. 3 is an electron micrograph showing the particle structure (dispersion morphology) of the film obtained in Comparative Example 8 (cross section parallel to the tensile direction), and FIG. 4 is the film obtained in Example 7 (parallel to the tensile direction). 2 is an electron micrograph showing a particle structure (dispersion morphology) of a different cross section.

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[Procedure amendment]

[Submission date] Hei 4.1.27 (1) Amended the description in the claims as attached. (1) "Toughness" is added after "For good" on page 3 of the specification (1) "To (A)" on page 3, line 3 of the same page "(A) as matrix"
Corrected (1) Ibid., Page 5, line 11, “0.50” was corrected to “0.45” (1) Id., Page 7, lines 4-5, “Mutual intrusion ... understood.” “Matted continuous phase in matrix (A) It is shown that a large amount of polycarbonate (B) is formed. ”(1) Ibid., Page 11, line 19 to page 12, line 8“ 95% to 50 parts by weight of (A) ... reduced. ” Corrected as `` (A) is 95 to 55 parts by weight, (B) is preferably 5 to 45 parts by weight, more preferably (A)
Is preferably 92 to 70 parts by weight, and (B) is 8 to 30 parts by weight. When the content of the polycarbonate resin (B) is too large, the excellent properties of the polyester resin are lost, which is not preferable. Further, if the content of the polycarbonate resin is too low, the formation of the interpenetrating network structure will be insufficient even if the component (C) is added, and the effect of improving the physical properties will be reduced. (1) Correction of page 13, lines 5 to 8 "Physical properties are the same." Is corrected as follows: "It exerts a remarkable effect on mechanical properties, but especially the inflation method, T-die method, etc. are usually performed. A film or sheet prepared by the film forming method is particularly suitable because it has excellent properties as a film such as tear strength. "(1) After page 13, line 16, line" Colorant ",", flame retardant, antistatic agent, conductive material " (1) p. 14, line 7, line "styrene" followed by "(about 20% by weight)"
(1) Corrected "Highly expected ..." on page 24, line 6-10, as follows: "Improved mechanical properties (impact strength and toughness), especially tearing when used as a film or sheet. It is possible to significantly improve strength and impact strength. ”

[Claims]

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Internal reference number FI technical display area C08L 67:02

Claims (6)

[Claims] 1. A polyalkylene terephthalate resin (A)
In addition, when the polycarbonate resin (B) is melt-kneaded and mixed, the acrylic graft (co) polymer particles (C) having an average particle size of 10 μm or less and not flowing at the melt-kneading temperature are expressed by the following formula (1) ) And (2) are added in a blending amount that satisfies the above conditions and melt-kneaded, and a method for producing a molded product in which the components (A) and (B) intrude into each other to form a network structure. Formula (1) B / (A + B) = 0.05 to 0.50 (weight ratio) Formula (2) C / (A + B + C) = 0.005 to 0.30 (weight ratio) 2. A polyalkylene terephthalate resin (A)
The method for producing a molded article according to claim 1, wherein is a polybutylene terephthalate or a copolymer mainly composed of polybutylene terephthalate. 3. An acrylic-based graft (co) polymer, which is obtained by polymerizing an acrylic acid alkyl ester as a main component, optionally together with a vinyl-based monomer, and using a crosslinking agent and / or a graft crossing agent. The method for producing a molded article according to claim 1, which is a system-based graft (co) polymer. 4. A molded article produced by the production method according to claim 1, wherein the components (A) and (B) intrude into each other to form a network structure. 5. The molded product according to claim 4, wherein the molded product is an extruded film. 6. The molded product according to claim 4, which is a molded product obtained by injection molding or blow molding.