JPS6169848A - Polypropylene resin composition - Google Patents

Abstract

PURPOSE:To obtain a polypropylene resin compsn. which gives moldings which have a high mechanical strength and good surface appearance and little cause warpage and deformation, by blending a fibrous filler and talc in a specified ratio with a polypropylene resin. CONSTITUTION:A compsn. contains 40-92wt% polypropylene resin (A), 3-30wt% fibrous filler (B) having an average fiber diameter of 0.1-2mum and an aspect ratio of 20-60 and 5-35wt% talc (C) having an average particle size of 0.3-3mum in a weight ratio of B/C of 1/9-2/1. Pref. a silane coupling agent and/or a modified polyolefin are/is blended with the compsn. to give moldings having further improved strength. Pref. an elastomer is blended to give moldings having improved impact strength.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention provides a polypropylene resin reinforced with a fibrous filler and a non-fibrous filler, which can be suitably used in technical fields such as automobiles and electricity. Regarding the composition.

[Prior Art and its Problems] Polyolefin reinforced with inorganic fillers is widely used as an important material mainly in the field of industrial materials such as automobiles and light electrical appliances. In these fields, materials are required that have high mechanical strength, have a beautiful surface appearance, and do not cause deformation.

However, in the past, various attempts have been made to improve polyolefin resins in order to meet the demands of the above-mentioned fields.
At present, there is still no material that satisfies all the properties required in the above field. For example, glass! Polyolefin resin reinforced with TA fibrous filler centered on A fibers,
Although some significant improvements in strength and rigidity have been observed, there are drawbacks such as a decrease in impact strength, deterioration of the surface appearance of molded products, warping, and deformation. Further, although polyolefin resins reinforced with non-fibrous fillers such as calcium carbonate and talc do not have the above-mentioned drawbacks, they have problems such as little improvement in strength, heat-resistant rigidity, etc.

[Means for Solving the Problems] This invention has been made based on the above circumstances. After intensive research into the development of a polypropylene resin composition as a material suitable for the fields of automobiles, electricity, etc., the inventor found that a fibrous filler of #1 and a specific non-11I
When fibrous fillers are blended with polypropylene resin in specific proportions, a polypropylene resin composition that can be molded into a molded product with high mechanical strength, good surface appearance, no deformation, and good dimensional stability can be obtained. This invention was achieved by discovering that the following can be obtained.

That is, an object of the present invention is to provide a polypropylene resin composition that has high mechanical strength, such as impact strength and heat-resistant rigidity, has a good surface appearance, and provides a molded article with significantly less warpage and deformation.

The outline of the present invention for achieving the above object is that the polypropylene resin (A) is 40 to 92% by weight and the average fiber diameter is 0.
．． 3 to 30% by weight of the m male filler (B), which is 1 to 2 pots and has a seven-spectrum ratio of 20 to 60, and 5 to 35% by weight of talc (C), which has an average particle size of 0.3 to 3μ. %, and the blending weight ratio (B)/('C) is 179 to 2/1.

The polypropylene resin used in this invention is not particularly limited as long as it is generally used as a molding material, etc. Therefore, it may be a propylene pomopolymer, a coffi polymer of propylene and an α-olefin, for example, a propylene-ethylene block copolymer. Copolymer, propylene-ethylene random copolymer, etc. can be used. Among the various polypropylenes, crystalline polypropylene homopolymers, propylene-ethylene block copolymers and propylene-ethylene random copolymers are preferred.

m in this invention! The I-shaped filler has an average fiber diameter of σ, 1~? It is a tile, and preferably has a size of 0.5 to 1 舊 and an aspect ratio of 20 to 60.

It is important that the number is preferably 30 to 50.

When the average m fiber diameter of the m#1 filler becomes smaller than 0.1 island, the bulk specific gravity becomes too small and it becomes difficult to mix it with other ingredients, and even if it can be blended, the dispersion of this m#1-shaped filler will be difficult. It becomes. Furthermore, if the average m'a diameter exceeds 2 uL and the aspect ratio exceeds 60, the surface appearance of a molded article formed using this polypropylene resin composition will be poor. If the average fiber diameter exceeds 0.2 l and the aspect ratio is less than 20, the rigidity of a molded article formed using this polypropylene resin composition will not improve.

The m male filler in this invention may be of any material as long as it satisfies the above conditions, such as fibrous magnesium oxysulfate, titanium ugly potassium m male, glass fiber, calcium silicate fiber, alumina silica glass am. Examples include certain ceramic fibers, carbon fibers, rock wool, silicon nitride whiskers, and the like. Among the various fibrous fillers, la male magnesium oxysulfate, potassium titanate fiber, glass am
, calcium fiber, etc. are preferred.

・The talc in this invention has an average particle diameter of 0.3 to 3
It is important that the length is 0.5 to 1, preferably 0.5 to 1. If the average particle diameter of the talc is less than 0.3°, the dispersibility of the talc will be poor. In addition, the average particle diameter is 3
When the swell exceeds the peak, the impact strength of the molded article molded using this polypropylene resin composition decreases, and scratches and whitening phenomena become noticeable. The talc used in this invention is not particularly limited as long as it satisfies the above conditions.

One of the important things about this invention is that the polypropylene resin composition contains 40 to 92% by weight of polypropylene resin #i.
and preferably 50 to 85% by weight, the fibrous filler in 3 to 30% by weight, preferably 5 to 20% by weight, and the talc in 5 to 35% by weight, preferably 10 to 30% by weight. It is to be included in

If the amount of the fibrous filler is less than 3% by weight, the rigidity of the molded product of the polypropylene resin composition will not improve, and if it exceeds 30% by weight, the production of the polypropylene resin composition itself will be impaired. Even if it were possible to manufacture it, the impact strength of molded products made from this polypropylene resin composition would be reduced.

If the amount of talc is less than 5% by weight, not only will the rigidity of the molded product of this polypropylene resin composition not improve, but it will not be effective in suppressing warpage of the molded product. %, the impact strength of the molded article will be lowered, the fluidity of the polypropylene resin composition will be lowered, and 70-marks may appear on the molded article.

Furthermore, one of the important things about this invention is that the blending ratio ffi of the fibrous filler and the talc is 1/9 to 2.
/1. If the blending weight ratio exceeds 2/1, warpage will occur in the molded product made from this polypropylene resin composition, and the dimensional stability will deteriorate; if the blending weight ratio is less than 1/9, the rigidity of the molded product will deteriorate. does not improve.

The polypropylene resin composition of the present invention greatly improves mechanical properties such as impact strength and heat-resistant rigidity by blending the polypropylene resin, the fibrous filler, and the talc in the specific mixing ratio. The surface appearance of the molded product is beautiful and there is no warping or deformation, but in order to further improve the strength of the molded product made of this polypropylene resin composition, silane coupling is added to the polypropylene resin composition. It is preferable to incorporate an agent and/or a modified polyolefin.

Either one of the silane coupling agent and the modified polyolefin may be blended, or both may be blended.

Examples of the silane coupling agent include vinyltriethoxysilane, vinyltrimethoxysilane, vinyltrichlorosilane, vinyldichloroethylsilane, vinyldiroloethylsilane, vinyltris(β-methoxyethoxysilane), and γ-glycidoxypropylene. biltrimethoxysilane, γ-7minopropyltriethoxysilane,
γ-methacroxypropyltrimethoxysilane, N-β
-(aminoethyl)-γ-aminopropyltriethoxysilane, N-β-(aminoethyl)-γ-7minopropylmethyldiethoxysilane, and the like.

The amount of the silane coupling agent blended is preferably 0.1 to 3 parts by weight based on the total of 10,021 parts of the polypropylene resin, the fibrous filler, and the talc. If it is less than 0.1% by weight, the strength of the molded product made from this polypropylene resin composition may not improve, and the amount added is 3g! ,
If it exceeds 3% by weight of the silane coupling agent, the increase in strength will reach saturation, and from a price point of view, 3% by weight of the silane coupling agent.
A combination exceeding this is disadvantageous.

Examples of the modified polyolefin include polyethylene, polypropylene, and ethylene propylene copolymers modified with unsaturated carboxylic acids, derivatives of unsaturated carboxylic acids, chlorine, and vinylsilane. Examples of the unsaturated carboxylic acids used in the modification include acrylic acid, methacrylic acid, maleic acid, fumaric acid, itaconic acid, crotonic acid, citraconic acid, sorbic acid, mesaconic acid, and angelic acid. Derivatives of saturated carboxylic acids include acid anhydrides, esters, amides, imides, metal salts, etc., such as maleic anhydride, itaconic anhydride, and citraconic anhydride.

Methyl acrylate, ugly methyl methacrylate, ethyl acrylate, butyl acrylate, maleic acid monoethyl ester, acrylamide, maleic acid monoamide, maleimide, N-butylmaleimide, sodium acrylate,
Examples include sodium methacrylate.

Among the various modified polyolefins, polypropylene modified with anhydrous malemono-ugly is particularly preferred.

The amount of the modified polyolefin described in iW is preferably 0.1 to 5 parts by weight based on the total of 100 parts by weight of the polypropylene resin, the fibrous filler, and the talc. If the amount is less than 1 part by weight, the strength of the molded product made from this polypropylene resin composition may not improve significantly, and if the amount exceeds 5 parts by weight, there will be no increase in strength corresponding to the increase in the amount. , the more it is added in excess of 5 parts by weight, the more disadvantageous it becomes in terms of price.

In order to further improve the impact strength of a molded article made from the polypropylene resin composition of the present invention, it is preferable to incorporate an elastomer.

Examples of the elastomer include styrene-ethylene-butadiene-styrene rubber (S-E-B-S),
Styrene-butadiene-styrene rubber (S-B-3)
, Styrene-isoprene-styrene rubber (S-I-3
), styrene-based elastomers such as styrene-butadiene rubber (S-B), and refine-based elastomers such as ethylene propylene rubber and ethylene propylene diene rubber, and styrene-butadiene rubber and ethylene propylene rubber are particularly preferred.

The blending amount of the elastomer is a total of 100% of the polypropylene resin, the fibrous filler, and the talc.
It is preferable to set it to 3 to 20 parts by weight based on the weight part. If this amount exceeds 20 parts by weight, the rigidity of the molded product made of this polypropylene resin composition, especially at high temperatures, will decrease significantly, and The hardness of the surface of the molded product may decrease significantly.

In addition to the above-mentioned components, the polypropylene resin composition of the present invention optionally contains an antioxidant and a flame retardant.

It may contain additives such as ultraviolet absorbers, antistatic agents, lubricants, mold release agents, and colorants.The amount of these additives is determined depending on the mechanical properties and surface appearance of the molded product made from this polypropylene resin composition. Needless to say, it is to the extent that it does not interfere with the process, and does not cause warping or deformation.

The polypropylene resin composition of the present invention contains the polypropylene resin, the fibrous filler, the talc, if necessary the silane coupling agent, a modified polyolefin, an elastomer, and various additives in a predetermined proportion, It can be obtained by sufficiently uniformly kneading by a combination method of dry mixing and melt mixing, a multistage melt mixing method, a simple melt mixing method, or the like. The cross-mixing operation can be carried out using, for example, an open roll, a panburi mixer, a V-type blender, an axle screw extruder, a two-wheel screw extruder, a co-kneader extruder, a multi-screw extruder, and the like.
- The polypropylene resin composition thus obtained can be molded into various molded products by various processing methods such as injection molding, extrusion molding, blow molding, compression molding, vacuum molding, pressure molding, lamination molding, roll processing, and stretching processing. be done. The molded product obtained has good mechanical properties, an extremely good surface condition, and very little warpage or deformation.
This polypropylene resin composition is very useful as a material for industrial material fields such as automobiles and electrical fields.

[Effects of the Invention] The polypropylene resin composition according to the present invention can significantly improve the mechanical strength, such as impact strength and heat resistance strength, of molded products, improve the surface appearance, and reduce warpage, deformation, etc. . -Furthermore, by blending a silane coupling agent and/or modified polyolefin with this polypropylene resin composition, the mechanical strength of the molded product can be further improved, and by blending an elastomer, the impact strength of the molded product can be improved. can be done.

Such characteristics of this polypropylene resin composition are such that a polypropylene resin, a specific fibrous filler, and a specific talc are blended in a limited blending ratio, and the blending weight ratio of the fibrous filler and the talc is controlled. This can only be achieved by setting the value within a specific range.

[Example] Next, the present invention will be described in more detail by showing Examples and Comparative Examples.

(Example 1.2) Propylene-ethylene block copolymer (abbreviated as EP) (MI = 6 g/10 min, ethylene content: 9% by weight, ) 70% by weight, average fiber diameter shown in Table 1 ,
20% by weight of a fibrous filler of the type shown in Table 1 having an aspect ratio and 10% by weight of talc with an average particle size of 0.8 were thoroughly mixed in a V-type blender, and then melt-mixed in a -shaft extruder. A pellet was obtained.

This pellet was injection molded at 200°C to prepare a test piece.

The following physical properties were measured using the test piece.

The results are shown in Table 1.

[Izot impact strength] Measured in accordance with ASTM D256 (notched).

(Falling weight impact strength) Measured in accordance with JIS K7211. Strike radius 1
/4 inch, falling weight pedestal 50φ (flexural modulus) Measured in accordance with ASTM 0790.

(Surface appearance) Injection molded at a molding temperature of 200°C and a mold temperature of 50°C.
The surface roughness of a flat plate measuring 40 x 140 x 3 mm was visually observed and evaluated.

(Warpage rate) The warp height of the disk at both ends in the diametrical direction after leaving it for 48 hours at a room temperature of 23°C, after an injection molded disk with a thickness of 2 mm, a diameter of 150 am, and a center gate diameter of 5 m. H(1 鳳) and h(+u+) were measured and the warpage rate was determined according to the quintic equation.

Xh Warp rate=YYT■1×1OO (Hereinafter, blank) The relationship between the warp-related symbols in Table 1 and the warp rate is as follows.

The same procedure as in Example 1 was carried out except that the type of fibrous filler shown in Table 1 having the average fiber diameter and aspect ratio shown in Table 1 was used.

The test results of physical property measurements are shown in Table 1.

As is clear from Table 1, test pieces of polypropylene resin compositions containing fibrous fillers with average fiber diameters in the range of 0.1 to 2 l and aspect ratios in the range of 20 to 60. 1 has a high bending modulus, high isot impact strength, and high falling weight impact strength, has a good surface appearance, and does not cause warping.

(Example 3) The same procedure as in Example 1 was carried out except that the blending ratios of the propylene-ethylene block copolymer, fibrous magnesium oxysulfate, and talc were changed as shown in Table 2. The results are shown in Table 1.

In addition, the scratch whitening property was evaluated as follows.

(Scratch and whitening property) Using a Taber scratch tester, a scratch was made on the test piece with a cutter while applying a load of 150 g. Using a 0-order dark field polarizing microscope, a halogen light of a constant X[k was applied to the hot water part. was incident on the ring from a 45 degree direction and converted into a current value. This current value was substituted into the following equation to determine the scratch whitening degree.

(A: Measured value of intact area, B: Measured value of hot water area) These values were ranked and evaluated as follows.

The relationship between the degree of whitening due to scratches and the degree of visual whitening is also shown below.

(Example 4) 1 part by weight of polypropylene modified with maleic anhydride (acid addition amount: 5% by weight) was blended with 100 parts by weight of the composition of Example 3 to obtain pellets of a polypropylene resin composition. Test pieces were prepared using pellets in the same manner as in Example 1, and various physical properties were measured.

The results are shown in Table 2.

(Hereinafter, blank spaces) (Example 5) The same procedure as in Example 1 was carried out except that the blending ratios of the propylene-ethylene block copolymer, fibrous magnesium oxysulfate, and talc were changed as shown in Table 2.

The results are shown in Table 2.

(Example 6) To 100 parts by weight of the composition of Example 3, 3 parts by weight of polypropylene modified with maleic anhydride (5% by weight of acid addition) and 1 part by weight of γ-7 minobrobiltriethoxysilane were added. A pellet of the polypropylene resin composition was obtained by blending, and a test piece was prepared using the pellet in the same manner as in Example 1, and various physical properties were measured.

The results are shown in Table 2.

(Comparative Example 5) The same procedure as in Example 5 was carried out except that talc having an average particle size of 12 μl was used.

The results are shown in Table 2.

In Table 2, from the comparison between Example 3 and Example 4 and the comparison between Example 5 and Example 6, it is clear that the addition of modified polyolefin or the addition of modified polyolefin and silane coupling agent was Improves physical properties and scratch and whitening resistance. Moreover, as is clear from Comparative Example 5, when the average particle diameter of talc is outside the range of 0.3 to 3.0 mm, the mechanical properties and scratch-whitening resistance of the molded article made of the polypropylene resin composition deteriorate.

(Hereinafter, blank space) (Example 7) Propylene-ethylene block copolymer (MI = 10g
/10 minutes, EthiL/7 content; 5% by weight) 70% by weight,
Potassium titanate fiber with an average fiber diameter of 0.3μ and an aspect ratio of 50! 110% by weight and 20% by weight of talc with an average particle size of O, aμ were blended in the same manner as in Example 1 to obtain a pellet of a polypropylene resin composition, and test pieces were prepared to measure various physical properties. .

The results are shown in Table 3.

(Example 8) Ethylene-propylene rubber (Mooney viscosity 24, MI =
3.5 g/10 minutes) to obtain a polypropylene resin composition, test pieces were prepared, and various physical properties were measured.

The results are shown in Table 3.

(Example 9) PropyL/ethylene copolymer (MI=10g/10
15 parts by weight of fibrous magnesium oxysulfate with an average fiber diameter of 0-a = 40 and an aspect ratio of 40, and 153 TE of talc with an average particle diameter of 0.8. , total of each component 100i
Styrene-butadiene rubber (M I =
6 g/10 minutes) to obtain a polypropylene resin composition, test pieces were prepared, and various physical properties were measured.

The results are shown in Table 3.

(Example 10) Propylene-ethylene block copolymer (MI=10
g/10 min, ethylene content 5% by weight) 70% by weight,
15i3i% of fibrous magnesium oxysulfate with an average fiber diameter of O, aμ and an aspect ratio of 40, 15% by weight of talc with an average particle diameter of 0.8μ, and a total of 10% of each of the above components.
Styrene-butadiene rubber (M I
= 6g/10 minutes), 2 parts by weight of maleic anhydride-modified polypropylene (addition amount; 531!% by weight), and 1 part by weight of γ-7 minopropyltriethoxysilane to form a polypropylene resin composition. was obtained, test pieces were prepared, and various physical properties were measured.

The results are shown in Table 3.

(Comparative Example 6) The same procedure as in Example 7 was carried out, except that potassium titanate fibers with an average fiber diameter of 0.3 and an aspect ratio of 50 and talc with an average particle diameter of 12 laps were used as the fibrous filler.

The results are shown in Table 3.

(Comparative Example 7) The same procedure as in Example 9 was carried out except that glass fiber having an average fiber diameter of 13 and an aspect ratio of 230 was used as the fibrous filler.

The results are shown in Table 3.

As is clear from Table 3, the polypropylene resin composition containing an elastomer is larger than the polypropylene resin composition containing no elastomer! ! In addition, a polypropylene resin composition containing an etestomer, a modified polyolefin, and a silane coupling agent has a higher flexural modulus and impact strength than one without these. Moreover, the surface condition is good.

Also, from the results of Comparative Examples 6 and 7, the average particle size of talc is 3
is larger than μ, and the average fiber diameter is larger than 2 l,
If the aspect ratio is larger than 60, the J11 mechanical strength and surface condition will be poor.

(Hereafter, margin)

Claims (3)

[Claims] (1) 40 to 92% by weight of polypropylene resin (A);
3 to 30% by weight of a fibrous filler (B) having an average fiber diameter of 0.1 to 2μ and an aspect ratio of 20 to 60, and talc (C) having an average particle diameter of 0.3 to 3μ. ~3
5% by weight, and the blending weight ratio (B)/(C) is 1/9
2/1. (2) 0.1 to 3 parts by weight of a silane coupling agent and/or 0.1 to 5 parts by weight based on a total of 100 parts by weight of the polypropylene resin, the fibrous filler, and the talc.
Claim 1 containing parts by weight of modified polyolefin
The polypropylene resin composition described in . (3) Claim 1 or 2, which contains 3 to 20 parts by weight of an elastomer based on a total of 100 parts by weight of the polypropylene resin, the fibrous filler, and the talc. polypropylene resin composition.