JP3464828B2 - Polyester-polyolefin resin composition and method for producing the same - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polyester resin composition containing a polyolefin resin and a method for producing the same, and provides a molding material which is lightweight and has good surface condition and mechanical properties.

[0002]

2. Description of the Related Art Thermoplastic polyesters typified by polyethylene terephthalate and polybutylene terephthalate are easy to process,
It has been widely used in the field of automobile parts, electric / electronic equipment parts, and other precision equipment parts due to its excellent mechanical properties and other physical and chemical properties. In many cases, it is required to improve the mechanical properties, particularly toughness, and it is often required to reduce the weight in handling. Therefore, as one means for responding to these demands, a method of blending a thermoplastic polyester with a polyolefin resin having a smaller specific gravity than the polyester can be considered. However, since the polyester and the polyolefin resin have poor compatibility, not only dispersion kneading may occur simply by melt kneading and peeling easily occurs on the surface of the molded product, but also the impact strength decreases.
After all, there is a problem that a resin composition that can be used practically cannot be obtained. Therefore, as a means for solving such a problem, it is proposed to use a specially modified polyolefin resin as a method for improving the compatibility between the above-mentioned polyester and the polyolefin resin (for example, JP-A-61-60744, JP-A-61-60744). JP-A 61-60746 and JP-A-3-285931) and a method of improving the compatibility of both by blending a special compatibilizer together (for example, JP-A-6-73264). However, even if these methods are used, the compatibility between the polyester and the polyolefin resin cannot be said to be sufficient, and the use of a special modified polyolefin or a compatibilizer results in high cost and is economical. However, it is not a preferable method, and further improvement is desired.

[0003]

Means for Solving the Problems As a result of intensive studies for solving these problems, the present inventors have found that an aromatic dicarboxylic acid or its ester-forming derivative and an aliphatic diol or its ester-forming derivative are During synthesis, an ester-forming compound containing a specific halogen is added, and a polyolefin polymer is allowed to coexist during the polycondensation reaction to form a composition in which the polyester and the polyolefin polymer have extremely good dispersibility. It discovered that, and completed the present invention. That is, the present invention is (A) an aromatic dicarboxylic acid or an ester-forming derivative thereof, (B) an aliphatic diol or an ester-forming derivative thereof, and (C) an ester-forming compound containing a halogen-containing ester-forming compound. After preparing the aromatic polyester copolymer having a halogen content of 0.5 to 30 wt% obtained by polycondensation after the transesterification reaction, in the polycondensation reaction step, (D) a polyolefin-based polymer, which produces an aromatic compound It is a method for producing a polyester-polyolefin resin composition, which comprises coexisting in an amount of 5 to 70 parts by weight with respect to 100 parts by weight of a group polyester.

A feature of the present invention is that when a polycondensation reaction is carried out through an esterification or transesterification reaction using an ester-forming monomer compound to produce a polyester, a halogen-containing esterified monomer is allowed to coexist, and at least its weight is reduced. A polycondensation reaction is carried out in the presence of a polyolefin-based polymer at the time of condensation, and at least a part of the polyolefin is chemically bound to the produced polyester by such a method, and the polyester-polyolefin conjugate is other polyester and polyolefin. It is extremely effective in improving the affinity between the homopolymers, and a composition of polyester and polyolefin having excellent dispersibility which cannot be obtained only by melt-kneading polyester and polyolefin is obtained. This means that in the case of the present invention, the product composition is pulverized and extracted with m-xylene, which is a good solvent for polyolefin, and the residue is further extracted with hexafluoroisopropanol, which is a good solvent for polyester. It is considered that the polyolefin-grafted polyester is produced since the components insoluble in the solvent are collected and recovered. On the other hand, during the polycondensation of the polyester, when the halogen-containing ester-forming compound is not present, almost all of the compound is eluted by the two-solvent extraction with respect to the product composition, and
The above reasoning is supported by the fact that even a composition prepared by preparing a halogen-containing polyester by a polycondensation reaction in advance and then melt-kneading the polyolefin with an extruder has almost no extraction residue.

The polyester-polyolefin resin composition of the present invention and the method for producing the same will be described below in detail. First, the components constituting the aromatic polyester copolymer which is the base of the composition of the present invention will be explained. As the component (A), an aromatic dicarboxylic acid or its ester-forming derivative is used. A typical substance thereof is terephthalic acid or an alkyl ester thereof, for example, a methyl ester. In addition to this, dicarboxylic acid or a derivative thereof such as isophthalic acid, naphthalenecarboxylic acid or naphthalenedicarboxylic acid, adipic acid, sebacine may be supplementarily added. acid,
Fatty acids such as trimellitic acid and succinic acid or ester-forming derivatives thereof, and aromatic hydroxycarboxylic acids such as hydroxybenzoic acid and hydroxynaphthoic acid or ester-forming derivatives thereof are used.

Next, an aliphatic diol or its ester-forming derivative is used as the component (B) for constituting the polyester copolymer of the present invention. A typical substance thereof is a C _{2 to} C ₆ low molecular weight glycol such as ethylene glycol, 1,4-butanediol, 1,3-propanediol, 1,4-butenediol, 1,6-hexanediol, Examples include diols such as 1,8-octanediol. In addition to these low molecular weight glycols, high molecular weight glycols such as polyalkylene oxide glycols such as polyethylene oxide glycol and polybutylene oxide glycol can be used in combination. Of these, preferred are ethylene glycol and
It is 1,4-butanediol, with 1,4-butanediol being particularly preferred.

Next, the polyester copolymer of the present invention is an aromatic polyester copolymer having halogen bonded in its molecule by using an ester-forming compound containing halogen as the component (C) as a monomer. Is generated. Examples of the halogen-containing compound used for this purpose include the following (1) to (7). In addition, as the halogen, bromine is particularly preferable in terms of reactivity, cost and safety.

[0008]

[Chemical 1]

[0009] _{R 3, R 4; -C 2} H 4 -, - C 3 H 6 -, - (C 2 H 4 O) p
− _{, - (C 3 H 6 O} ) p - X; represents an integer of 1 or more; halogen m, n; 1 to 4 p. Preferred halogen compounds to be incorporated as a copolymer are those represented by the general formulas (1) to (6),
It is particularly preferable that the number of halogen atoms contained in one molecule is 4 or more. When bromine is used as the halogen, examples of general formula (1) are tetrabromobisphenol A, tetrabromobisphenol sulfone, tetrabromobisphenol F, and examples of (2) are tetrabromobisphenol A ethylene oxide 2 mol adducts. Tetrabromobisphenol A propylene oxide 2 mol adduct, tetrabromobisphenol sulfone ethylene oxide 2 mol adduct, tetrabromobisphenol sulfone propylene oxide 2 mol adduct, tetrabromohydroquinone as an example of (3),
An example of (4) is an ethylene oxide 2 mol adduct of tetrabromohydroquinone, an example of (5) is tetrabromoterephthalic acid, and an example of (6) is a polycarbonate of tetrabromobisphenol A. The compound (2) is particularly preferable, and among them, an ethylene oxide 2 mol adduct of tetrabromobisphenol A is preferable from the viewpoints of ester forming ability and cost. These halogen compounds have a halogen content in the resulting copolyester.
0.5 to 30% by weight, preferably 2 to 20% by weight is added. If it is less than 0.5% by weight, sufficient compatibility and dispersibility with the polyolefin, which is the object of the present invention, cannot be obtained, and if it exceeds 30% by weight, mechanical properties deteriorate, which is not preferable.

The proportion of the monomer for preparing the polyester copolymer used in the present invention is (A) when the ester-forming functional group of the halogen compound of the component (C) is an alcohol type.
The component (B) + (C) is used in an amount of 90 to 200 mol, preferably 95 to 150 mol, per 100 mol of the component. Further, when the ester-forming functional group of the halogen compound of the component (C) is a carboxylic acid type, 90 to 200 moles of the component (B), preferably 95 to 100 moles of the component (A) + (C) are used. 150 mol is recommended.

The above-mentioned component (C) is generally known as a copolymerization component for flame retarding a polyester, but in the present invention, the halogen in the polyester constituent component is bonded to the polyolefin during polycondensation. Involved in formation, not only imparting flame retardancy, but also forming a graft copolymer of polyester and polyolefin, which acts as a compatibilizer, contributing to the improvement of the compatibility and dispersibility of the composition of the present invention. In the case where the halogen-containing monomer is not contained, the compatibility improving effect cannot be obtained even if the polyolefin is present during the polycondensation.

Next, the polyolefin polymer (D) constituting the composition of the present invention will be described. The polyolefin-based polymer (D) used in the present invention includes polypropylene, polyethylene, polymethylpentene, polybutene,
Alternatively, it may be a copolymer containing these as main components, for example, an ethylene / propylene copolymer, an ethylene / propylene / diene copolymer, or a copolymer containing a monomer other than olefin. In particular, a polyolefin having a methyl group in its side chain is preferable, and typical examples thereof include polypropylene and polymethylpentene.
In addition, a polyolefin containing propylene or methylpentene as a copolymerization component is also preferred. These polyolefin-based polymers may be used alone or as a mixture of two or more. These polyolefins are particularly effective in compatibility and dispersibility with the polyester resin, and are effective in improving toughness without impairing the rigidity of the composition. The amount of the polyolefin added and blended in the present invention is 5 per 100 parts by weight of the aromatic polyester produced.
˜70 parts by weight, preferably 10 to 50 parts by weight. If the amount added is too small, one of the objectives is insufficient weight reduction, insufficient toughness, and if it is too large, the compatibility and dispersibility become insufficient, and the original characteristics of aromatic polyester Is lost and physical properties are also hindered, which is not preferable.

The preparation of the composition of the present invention is characterized in that the polyolefin is reacted and added during the polycondensation of the polyester. As the polycondensation method, it is possible to use known methods such as melt polymerization, solution polymerization, interfacial polymerization, solid phase polymerization, etc., but melt polymerization, or after that, if necessary, further auxiliary solid phase polymerization is carried out. Is common and preferred. In melt polymerization, the components (A), (B), and (C) are usually heated and melted under atmospheric pressure in the presence of a catalyst to obtain a low molecular weight oligomer by esterification or transesterification, and then gradually reduced pressure is applied. Then, a two-step reaction including a polycondensation reaction in which the temperature is raised to obtain a high polymer is used. The component (D) of the present invention is preferably allowed to coexist in the reaction system at least after the latter half of the polycondensation step in the polyester preparation step described above, and allowed to stand at a temperature of 250 ° C. or higher for 30 minutes or longer, in advance (A) to (( It may be added to the reactor at the same time as the monomer component C), or may be added after the esterification or transesterification reaction and before or after the polycondensation reaction and mixed with the reaction system. The polycondensation reactor used in the present invention may be a one-tank type or a batch type polymerization device in which a plurality of reactors are combined, a batch type polymerization device or various continuous polymerization devices.

The resin of the present invention may be used together with the component (D) within a range that does not impair the effects of the present invention, or after preparation of the above polyester composition, other thermoplastic resin or organic or inorganic filler depending on the purpose. Can also be supplementarily added and blended. The thermoplastic resin used in this case is not particularly limited, but examples thereof include other polyolefin resins such as polyethylene, polystyrene resins (AS, ABS resins, etc.), polyvinyl chloride, polyamide resins, polycarbonate, polyphenylene. Examples thereof include oxides, polyphenylene sulfides, fluororesins and the like. Further, two or more kinds of these thermoplastic resins can be mixed and used. As the inorganic filler, various fibrous, powdery or plate-like inorganic fillers can be blended depending on the purpose of use. Examples of the fibrous filler include glass fiber, asbestos fiber, silica fiber, silica, alumina fiber, alumina fiber, zirconia fiber, silicon nitride fiber, silicon nitride fiber, fiber, potassium titanate fiber, stainless steel fiber, aluminum and titanium. Inorganic fibrous substances such as fibrous substances of metals such as copper, copper and brass. On the other hand, as the particulate filler, carbon black, graphite, silica, quartz powder, glass beads, milled glass fiber, glass balloon, glass powder, calcium silicate, aluminum silicate, kaolin, talc, clay, diatomaceous earth, wollastonite Such as silicate, iron oxide, titanium oxide, zinc oxide,
Examples thereof include oxides of metals such as antimony trioxide and alumina, sulfates of metals such as calcium carbonate and magnesium carbonate, other ferrite, silicon carbide, silicon nitride and various metal powders. Examples of the plate-shaped filler include mica, glass flakes, various metal foils and the like. These inorganic fillers can be used alone or in combination of two or more.
As the organic filler, aromatic polyester fiber,
Examples include heat-resistant and high-strength synthetic fibers such as liquid crystal polymer fibers, aromatic polyamide, and polyimide fibers. The inorganic or organic filler used may be a known surface treatment agent in combination depending on the desired physical properties. Examples thereof include functional compounds such as epoxy compounds, isocyanate compounds, titanate compounds, and silane compounds. These fillers may be used after being surface-treated in advance, or may be added at the same time when the material is prepared. Here, the addition amount of the inorganic or organic filler is 0 to 60% by weight based on the total amount of the composition.

[0015]

INDUSTRIAL APPLICABILITY As described above, the resin composition obtained by the present invention is excellent in compatibility and dispersibility of the polyester resin and the polyolefin resin, and is dispersed as fine particles as compared with the case where the resin components are simply melt-kneaded. Since there is no problem such as peeling of the surface layer when formed into a molded product, the surface condition is good, the specific gravity is low, the rigidity and toughness are high, the heat resistance is excellent, and the thin-walled injection moldability is also good. Suitable for applications such as small parts for automobiles, and also suitable for large molded products.

[0016]

EXAMPLES The present invention will be described in detail below with reference to examples, but the present invention is not limited thereto. Examples 1 to 3 5 parts by weight of dimethyl terephthalate (DMT), 37.0 parts by weight of 1,4-butanediol (BD), 9.0 parts by weight of bisethoxy compound of tetrabromobisphenol A (TBBA) were placed in a stirrer, a distilling pipe and the like. The mixture was placed in a polyester polycondensation apparatus provided, and 0.07 parts by weight of tetrabutoxytitanium was added as a catalyst, and heated to 180 ° C. under normal pressure. Next, after the raw materials were melted, the temperature was gradually raised, and methanol produced by the transesterification reaction was distilled while stirring. Then
When the temperature reaches 250 ℃, polypropylene (PP)
(Noblene manufactured by Sumitomo Chemical Co., Ltd.) was put in the polymerization vessel at 10, 30 and 50 parts by weight respectively, and stirring was continued for 10 minutes to melt PP, and then the pressure in the polymerization vessel was gradually reduced to 0.1 torr. After continuing the stirring for 90 minutes to carry out polycondensation, the contents were discharged and cooled to obtain a polyester-polyolefin composition. The characteristic values of the obtained composition were measured as shown below. [Grafting rate] The grafting rate is determined by crushing the composition, extracting each soluble polymer by Soxhlet extraction method using hexaflucoroisopropanol (HFIP) and m-xylene as a solvent to separate the grafted polymer, and then removing the grafted polymer. Was determined (wt%). [Physical Properties] The obtained composition was pelletized, and an ASTM test piece was molded by an injection molding machine under the conditions of a cylinder temperature of 260 ° C and a mold temperature of 60 ° C, and a tensile test and an impact test were performed. [Appearance of Molded Article] The surface condition of the above-mentioned ASTM test piece was observed with the naked eye, and in particular, the surface peeling condition, uniformity, smoothness, etc. were evaluated. [Peeling test] After making 10 1mm-square cross-shaped cuts on the surface of the molded product with a cutter knife in length and width of 10 each, attach commercially available cellophane tape and make it adhere to the molded product, then tape under certain conditions Peel off the number of peeling points (100
(Middle) was measured to examine the tendency of surface layer peeling. The results are shown in Table 1.
Are shown together.

Example 4 The same operation and evaluation as in Example 2 were carried out except that polymethylpentene (PMP) (manufactured by Mitsui Petrochemical) was used instead of PP. The results are also shown in Table 1. Example 5 A test was conducted in the same manner as in Example 2 except that ethylene-propylene copolymer (EPR) was used instead of PP. Comparative Example 1 The procedure of Example 2 was repeated without adding TBBA. The results are shown in Table 1. Comparative Example 2 In Example 2, polycondensation was performed without adding polypropylene during polycondensation to obtain a bromine-containing polyester. Next, 100 parts by weight of this polyester and 30 parts by weight of polypropylene (PP) were melt-kneaded in an extruder at 240 ° C. to obtain a polyester-polyolefin resin composition, and evaluated in the same manner. The results are shown in Table 1.

[0018]

[Table 1]

* 1 Note: Melt kneading by adding to polyester after completion of polycondensation

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Claims (8)

(57) [Claims] 1. An esterification or ester using (A) an aromatic dicarboxylic acid or an ester-forming derivative thereof, (B) an aliphatic diol or an ester-forming derivative thereof, and (C) an ester-forming compound containing a halogen. After the exchange reaction,
When preparing an aromatic polyester copolymer having a halogen content of 0.5 to 30 wt% obtained by polycondensation, in the polycondensation reaction step, (D) a polyolefin-based polymer,
5 to 70 per 100 parts by weight of the aromatic polyester produced
A method for producing a polyester-polyolefin resin composition, characterized in that the polycondensation reaction is carried out in the presence of parts by weight. 2. The method for producing a polyester-polyolefin resin composition according to claim 1, wherein the component (A) is terephthalic acid or an alkyl ester thereof. 3. The method for producing a polyester-polyolefin resin composition according to claim 1, wherein the component (B) is 1,4-butanediol. 4. The method for producing a polyester-polyolefin resin composition according to claim 1, wherein the component (C) is bisethoxylated tetrabromobisphenol A. 5. The method for producing a polyester-polyolefin resin composition according to claim 1, wherein the component (D) is a polyolefin having a methyl group in its side chain. 6. The method for producing a polyester-polyolefin resin composition according to claim 5, wherein the component (D) is a polyolefin containing propylene or methylpentene as a main component. 7. The polyester-polyolefin resin according to claim 1, wherein the polycondensation is carried out in the coexistence of the polyolefin polymer via a polycondensation temperature of at least 250 ° C. Method of making the composition. 8. A polyester-polyolefin resin composition produced by the production method according to any one of claims 1 to 7.