JPH03217444A - Resin composition - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a resin composition comprising a modified polyolefin and a saturated polyester. More specifically, the present invention relates to a resin composition that has excellent moldability, rigidity, heat resistance, and electrical properties. Polyolefin resins are generally inexpensive, have excellent moldability, low moisture absorption, and low specific gravity, and are widely used in various fields. However, the rigidity at high temperatures is not fully satisfactory in terms of performance. On the other hand, various resins have been developed as plane-phase polyester resins, but
It generally has excellent heat resistance and oil resistance, and is widely used as an engineering resin in the fields of automobile parts, electrical, and electronic parts. However, this resin may be difficult to mold due to hydrolysis during the molding process. Furthermore, it has drawbacks such as deterioration of electrical properties due to hygroscopicity. Therefore, if it is possible to obtain a composition that combines the features of each of the above-mentioned resins and suppresses their defects, it would be of great industrial significance. It is an object of the present invention to provide such a composition. [Prior Art] As a method of combining the advantages of both polyolefin resin and saturated polyester resin as described above and compensating for the disadvantages,
For some time now, consideration has been given to creating a composition that combines both. However, these polyolefin resins and saturated polyester resins are inherently incompatible with each other and have no affinity, so if the two components are simply mixed, the adhesion at the interface of this two-phase horizontal structure may not be good. do not have. Therefore, the two-phase interface of the obtained molded product becomes a defective part, resulting in a decrease in mechanical strength and impact resistance. Furthermore, it is difficult for the two phases to form a uniform and finely dispersed form, and delamination is likely to occur when subjected to shear stress during molding processes such as injection molding. Generally, when blending these incompatible polymers, one possible method to solve the above problem is to blend a third component to improve the mutual affinity of the two components. be. Examples of this include a method in which an ethylene-based copolymer containing an epoxy group is used as a third component in addition to a polyester resin and a polypropylene resin (Japanese Patent Application Laid-Open No. 60744/1989), a method in which a polyester resin and a polypropylene modified with maleic anhydride are used together A method in which ethylene copolymers containing epoxy groups are used in combination (JP-A-61-6
0746), a method using a modified polypropylene resin obtained by graft copolymerizing a polyester resin and an unsaturated epoxy compound, and an ethylene copolymer containing an epoxy group (Japanese Patent Application Laid-open No. 1-213352). However, even in these compositions, the affinity between the modified polypropylene resin and the polyester resin is insufficient, and it is essential to use an ethylene-based copolymer containing an epoxy group in order to improve impact resistance. However, this resulted in a decrease in rigidity, making it difficult to balance rigidity and impact resistance at a high level.

[Problem to be solved by the invention]

The present invention was made with the aim of being able to solve the above-mentioned problems of the prior art without requiring the use of a third component in combination, and in which a polyolefin resin and a saturated polyester resin are homogeneously mixed and the process is carried out at the stage of molding. To provide a molding resin composition in which delamination, which is often observed when mixing incompatible resins, is suppressed, and the appearance of molded products is good, and the mechanical properties, including impact strength, are improved. It's about doing. [Means for Solving the Problems] As a result of intensive studies to achieve the above problems, the present inventors have developed a blend of a polyolefin resin modified with a silicon compound containing a hydrolyzable organic group and a saturated polyester. However, it was discovered that a resin composition obtained by melt-kneading can achieve the above objectives, and the present invention was achieved.

That is, the present invention provides (A) one-shell SiR,, Y3-n (where R is an aliphatic hydrocarbon group, Y is a hydrolyzable organic group or hydroxyl group, and n represents 0, 1 or 2) ) Modified polyolefin resin 5 containing a silicon compound residue represented by
95% by weight, and (B) 95 to 5% by weight of a saturated polyester resin.

Although it is not necessarily clear theoretically why a silicon compound having a hydrolyzable organic group is effective as a modifying component of component (A) in the present invention, it is thought to be as follows if inferred. It will be done. The silicon compound residue is
It is known to undergo condensation reactions with itself or with silanol groups. Therefore, in the case of the present invention, this silicon compound residue and the hydroxyl group of the saturated polyester resin bond to form a polyolefin grafted polyester type polymer, which is thought to contribute to the affinity of both resins. A polyolefin The polyolefin resin modified with a silicon compound having a hydrolyzable organic group, which is the component (A) used in the present invention, can be produced, for example, by the following method. That is, an ethylenically unsaturated silane is grafted onto an ethylene resin such as polyethylene and a copolymer mainly composed of ethylene, or a propylene resin such as a copolymer mainly composed of polypropylene and brobylene in the presence of a radical generator. A method of copolymerization (see Japanese Patent Publication No. 48-1711, JP-A No. 59-36115, etc.), or a method of high-pressure radical copolymerization of ethylene and ethylenically unsaturated silane, and optionally further with a radically polymerizable monomer. (Refer to Japanese Patent Publication No. Sho 62-23777, etc.).

However, in the present invention, the method for producing the modified polyolefin of component (A) is not limited to the above-mentioned method. Various methods can be applied, such as the method of obtaining
Furthermore, the silicon compound for modification is not limited to ethylenically unsaturated silane. The silicon compound for modification includes a silicon compound having a reactive group that can be grafted onto the olefin polymer, a silicon compound having a group capable of reacting with a functional group introduced into the olefin polymer, or a silicon compound that can be copolymerized with the olefin monomer. There are silicon compounds having a reactive group, and the following compounds are generally mentioned: R'S;RhY3-- Here, R゜ is, for example, a vinyl group, an allyl group, an imbrobenyl group, a butenyl group, a cyclo xenyl group or γ-《
meth)acryloyloxybutyryl group, etc. R is, for example, a hydrocarbon group such as an alkyl group such as a methyl group, an ethyl group, a probyl group, or a decyl group. Y represents a hydrolyzable organic group or hydroxyl group, and n is 0, 1 or 2.
Examples of Y include a methoxy group, an ethoxy group, a formyloxy group, an acetoxy group, a probionyloxy group, an alkyl group, and an arylamino group. Particularly preferred as the silicon compound for modification is C H
z = C H S i (O A )3 (where A
(represents an alkyl group having 1 to 8 carbon atoms), specific examples include vinyltrimethoxysilane and vinyltriethoxysilane.

Polyolefin resins modified with silicon compounds having hydrolyzable organic groups as described above include homopolymers of α-olefins such as ethylene, propylene, butene, and hexene, and copolymers of these α-olefins. These α-olefins include copolymers with other unsaturated monomers that can be copolymerized with these α-olefins. Specifically, low density polyethylene, medium density polyethylene, high density polyethylene, polypropylene, propylene-ethylene copolymer, ethylene-vinyl acetate copolymer, ethylene-(meth)acrylic acid copolymer and ionic crosslinked products thereof, Also includes ethylene-(meth)acrylic ester copolymers, mixtures of these polymers, and graft copolymers of the above polymers with maleic anhydride, (meth)acrylic acid, (meth)acrylic esters, etc. The modified polyolefin resin of component (A) may be a modified resin alone or a mixture of a modified resin and an unmodified resin.In this case, the modified resin and the unmodified resin The mixing ratio of can be arbitrarily set depending on the amount of the modifier introduced into the polyolefin resin, the mixing ratio of the polyolefin resin and the saturated polyester resin, etc.The amount of the modifier in component (A) is , usually 5% by weight
The content is preferably 3 to 0.1% by weight. If the amount of the modifier is more than this, the crosslinking reaction due to the silanol condensation reaction between the modified resins may progress during the resin mixing process, resulting in a decrease in moldability and mechanical strength of the resulting composition. ．． B Boriesur Various polyesters can be used as the saturated polyester resin which is component (B) used in the present invention. For example, one example is a thermoplastic polyester resin produced by condensing a dicarboxylic acid or its lower alkyl ester or acid halide or anhydride derivative with a glycol according to a conventional method. Aromatic and aliphatic dicarboxylic acids suitable for making this polyester include: Namely, oxalic acid, malonic acid, succinic acid, glutaric acid, adivic acid, suberic acid, azelaic acid, sebacic acid, terephthalic acid, isophthalic acid, p-carboxyphenoacetic acid, p,p'-dicarboxydiphenyl sulfone, p- Carboxyphenoxyacetic acid, p-Carboxyphenoxyprobionic acid, p
Monocarboxyphenoxyacetic acid, p-carboxyphenoxyvaleric acid, 2,6-naphthalene dicarboxylic acid, 2.7-
Naphthalene dicarboxylic acids and mixtures of these carboxylic acids are also used. Aliphatic glycols suitable for the production of polyesters also include linear alkylene glycols having 2 to 12 carbon atoms, such as ethylene glycol, 1,3-brobylene glycol, 1,4-butene glycol, 1.6
-hexene glycol and 1,12-dodecamethylene glycol. Examples of aromatic glycol compounds include p-xylylene glycol, birocatechol, resorcinol, hydroquinone, and alkyl-substituted derivatives of these compounds. Other suitable glycols include 1
．． 4-Cyclohexane dimethanol is also mentioned. Other preferred polyesters include polyesters produced by ring-opening polymerization of lactones. For example, bolivivarolactone, poly(ε-cabrolactone), and the like. Furthermore, other preferred polyesters include polymers (thermotrops) that form liquid crystals in a molten state.
ic Liquid Crystal Polymer
; TLCP). Polyesters that fall into these categories include Eastman Kodak's X7G and Dartco's Xydar.
Representative products include Sumitomo Chemical's Econol and Celanese's Vectra. Among the polyesters mentioned above as component (B),
Polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polynaphthalene terephthalate (PEN), poly-1,4-cyclohexane dimethylene terephthalate (PCT), liquid crystalline polyester, etc. are used in the resin composition of the present invention. Particularly suitable are saturated polyesters.

The composition of the present invention consists of the above-mentioned components (A) and (B), and the blending ratio of component (A) and component (B) is
) is in the range of 5 to 95% by weight, and component (B) is in the range of 95 to 5% by weight. Outside this range, the effect of adding small amounts of components is low and it is difficult to obtain a molding resin composition that combines the desired characteristics of both resins. In the present invention, other additional components can be added to the composition consisting of the components (A) and (B). For example, additives such as well-known antioxidants, weather resistance improvers, nucleating agents, flame retardants, and slip agents can be used in polyolefin resins, and well-known antioxidants and weather resistance improvers can be used in saturated polyester resins. Agents, plasticizers, fluidity improvers, mold release agents, nucleating agents, etc. can be used as additional components. Furthermore, organic and inorganic fillers and reinforcing agents, especially glass fibers, minerals, talc, wollastonite, potassium titanate, calcium carbonate, silica, etc., can improve rigidity, heat resistance, dimensional accuracy, dimensional stability, etc. It is valid. Depending on the actual use, well-known colorants and dispersants thereof may be used. Furthermore, impact strength improvers such as copolymers of unsaturated epoxy compounds and ethylene, copolymers of unsaturated epoxy compounds, ethylene and ethylenically unsaturated compounds, styrene-butadiene copolymer rubbers, and Addition of hydrides, ethylene-propylene-(diene) copolymer rubber, and its modified products with α,β monounsaturated carboxylic acid anhydrides, unsaturated glycidyl esters, unsaturated glycidyl ethers, etc. , is effective in improving the impact strength of the composition. The amount of the above-mentioned impact strength improver varies depending on the target physical properties, but for example, when improving the balance between rigidity and impact strength of the composition, 5 to 5 parts by weight per 100 parts by weight of the resin component of the composition. It is preferable to add 30 parts by weight. The resin composition of the present invention combines each of the above components with various mixers,
For example, it can be prepared by cross-mixing in a single-screw extruder, twin-screw extruder, Banbury mixer, or the like. Further, the order of mixing may be any possible order, but when mixing by the melt cross-fertilization method, it is preferable to mix sequentially starting from the one with the highest viscosity.

The present invention will be explained in detail below using Examples and Comparative Examples, but the scope of the present invention is not limited thereby.

[Examples 1 to 10) Each component used in the examples is as follows.

(Modified polypropylene) Density 0. To 100 parts by weight of powdered isotactic polypropylene with a melt flow index of 90 g/cm1 and 0.2 g/10 minutes, 0.5 parts by weight of penzoyl peroxide, 3 parts by weight of vinyltrimethoxysilane, and the antioxidant tetrakis[ After mixing methylene 3-(3.5-di-t-butyl-4-hydroxyphenyl)probionate with 0.2 parts by weight of methane for 2 minutes using a mixer, extrusion into an inner diameter of 40 mm and L/D of 2 3. 21 on the plane
Polypropylene modified with silane grafting was obtained by melt-mixing at 0°C. The melt flow index of this modified polypropylene is 10.5 g/10 minutes,
The content of vinyltrimethoxysilane was 2.6% by weight. (Modified polyethylene) Density 0.94g/cm', Melt flow index 1
．． By melt-mixing 0 g/10 min of high-density polyethylene in the same manner as the modified polypropylene,
Polyethylene modified with silane grafting was obtained. The melt flow index of this modified polyethylene is 1
．． 4 g/10 minutes, and the content of vinyltrimethoxysilane was 2.5% by weight. (Propylene-ethylene block copolymer) Propylene-ethylene block copolymer manufactured by Mitsubishi Yuka Co., Ltd. (trade name: Mitsubishi Bolipro [lC8D])
was used. (Saturated polyester) Polybutylene terephthalate manufactured by Mitsubishi Kasei Co., Ltd. (product name Novadol 5010), polyethylene terephthalate manufactured by Nippon Unibet Co., Ltd. (product name RT580C^), liquid-grade polyester manufactured by Celanese Co., Ltd. (product name Vectra^)
950) were used, respectively.

(Preparation of test piece) A resin selected from the modified polypropylene, modified polyethylene, and saturated polyester described above was heated in the ratio shown in Table 1 at a temperature 20°C higher than the melting point of each polyester, using TEX30 type manufactured by Japan Steel Works. It was extruded using a twin-screw kneader, cooled with water, and then pelletized. The pellets were dried for 12 hours in a vacuum dryer set at 120°C, and then test pieces for physical property evaluation were prepared using an injection molding machine and evaluated. Results first
Shown in the table.

[Comparative Examples 1 to 9] Evaluation level 0. 9 g/cm', isotactic polypropylene with melt flow index 12y/10 min, density 0. 9 4 g/cyx", melt flow index n only a/1n4}
The saturated polyesters shown in the Examples section above were mixed in the proportions shown in Table 2, and melted and kneaded under the same conditions as shown in the Examples to create test pieces and evaluate the physical properties. did. The results are shown in Table 2. [Comparative example 10, 1
1] Table 1 shows the physical properties when the modified polyolefin and saturated polyester used in the examples were used alone. The methods for evaluating physical properties in Examples and Comparative Examples are as follows. [Preparation of test pieces for evaluation] Injection molding was performed using a Meiki Seisakusho 840^-SJ injection molding machine at a cylinder temperature 20°C higher than the melting point of each saturated polyester used and a mold cooling temperature of 60°C. I created a piece. Immediately after molding, the test piece was placed in a desiccator and heated at 23℃ for 4 to 6 hours.
Evaluation was performed after leaving it for a day. (Bending elastic modulus) Measured using an Instron testing machine according to JIS K7203. (Izod impact strength) ISO 8180-1969 (JIS K7
110)4. : Accordingly, the unnotched Izod impact strength was measured using an Izod impact tester manufactured by Toyo Seisakusho.

(Water Absorption Rate) The weight change rate of the injection-molded test piece was measured after it was left in an atmosphere at a temperature of 23° C. and a humidity of 50% for 20 days.

(Layer peeling M) The gage 1 part of the injection molded test piece was bent by hand, and the state of the fractured surface was visually observed to determine the presence or absence of layer peeling. Judgment is shown in the following three types.

O: No peeling △: Partial peeling In addition, the composition exhibits a remarkable effect in that much better physical properties of molded articles can be obtained than those of the compositions shown in the comparative examples.

Therefore, the novel resin composition provided by the present invention is
It can be easily processed into molded products, films, sheets, etc. by molding methods normally used for thermoplastic resins, such as injection molding, extrusion molding, and blow molding, and has excellent uniformity and smoothness in appearance. In addition, it can provide products with an extremely good balance of physical properties such as rigidity, heat resistance, impact strength, chemical resistance, and water resistance.

Claims (1)

[Claims] (A) Represented by the general formula -SiR_nY_3_-_n (where R is an aliphatic hydrocarbon group, Y is a hydrolyzable organic group or hydroxyl group, and n is 0, 1 or 2) A resin composition comprising: 5 to 95% by weight of a modified polyolefin resin containing a silicon compound residue; and (B) 95 to 5% by weight of a saturated polyester resin.