JPH03200867A - Polyamide-polyolefin resin composition - Google Patents

Abstract

PURPOSE:To improve the friction and abrasion characteristics by compounding a polyamide resin, a modified polyolefin resin, a polypropylene resin, and a polytetrafluoroethylene. CONSTITUTION:80-30wt.% polyamide resin pref. contg. a large amt. of a terminal amino group, 1-40wt.% modified polyolefin resin contg. a functional group such as a carboxylic acid, metal salt, carboxylic acid ester, carboxylic acid anhydride, or epoxy group, and 20-70wt.% propylene (co)polymer resin are mixed. Then, 100 pts.wt. the resulting mixture is compounded with 5-30 pts.wt. polytetrafluoroethylene having a wt.-average mol.wt. of 50000-1000000.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a polyamide/polyolefin resin composition, and more specifically, it has both the excellent properties of polyamide resin and polypropylene resin, and has particularly excellent friction and wear resistance properties. The present invention relates to a polyamide/polyolefin resin composition.

[Prior art and problems to be solved by the invention] In general, polyamide resins are widely used as synthetic fibers due to their excellent physical and chemical properties.
In recent years, it has come to be used as a molding material. This is because polyamide resin is contained within thermoplastic resin and has high mechanical strength.

This is because it has excellent wear resistance, chemical resistance, heat resistance, and relatively excellent electrical properties, and has sufficient performance as an engineering plastic.

However, on the other hand, it has undesirable properties such as dimensional changes due to water absorption and a decrease in mechanical strength due to the amide group (-CONH-), which makes it less marketable as a molding material. Limited.

On the other hand, polypropylene resin is inexpensive and exhibits almost no water absorption, but has drawbacks such as being soft and having poor physical properties at high temperatures.

Therefore, in order to improve the respective drawbacks of polyamide resin and polypropylene resin, it is naturally possible to use these resins together, but a resin mixture obtained by mixing a polyamide resin and a polypropylene resin in a usual manner, Alternatively, a resin composition obtained by simply melting and kneading these materials has poor compatibility and cannot provide a composition with the desired excellent physical properties.

Therefore, we have traditionally developed resin compositions that combine the excellent properties of polyamide resins and polypropylene resins, namely the excellent electrical properties, heat resistance, mechanical strength, and oil resistance that polyamide resins have, as well as the low water absorption that polypropylene resins have. With the aim of obtaining a resin composition that has both hot water resistance, metal halide resistance, and low-temperature impact resistance,
The three components of polyamide resin, olefin polymer, and modified olefin polymer grafted with unsaturated carboxylic acid or its derivatives are melt-mixed to improve strength, heat deformation resistance, appearance,
Regarding obtaining a composition with excellent balance of moldability, Japanese Patent Publication No. 4212546 and Japanese Patent Publication No. 45
-30945, Japanese Patent Publication No. 50-7636, etc. In addition, utilizing these excellent properties, practical application is being considered in applications that require strength and heat deformation resistance such as automobile parts, electrical appliances, mechanical parts, industrial parts, etc., and in some cases, practical application is being considered. being done.

However, even with resin compositions having many of these characteristics, there is still a problem that the friction and wear characteristics are not sufficient. These resin compositions contain polypropylene resins, which have poorer friction and wear characteristics than polyamide resins, and therefore their applications are currently quite limited due to the limitations of polypropylene resins.

The present inventors have conducted intensive research with the aim of improving the friction and abrasion resistance in particular while maintaining the excellent properties of polyamide resins and polypropylene resins.

[Means to solve the problem]

As a result, the inventors discovered that the object could be achieved by blending a modified polyolefin resin and polytetrafluoroethylene in a certain ratio with the polyamide resin and polypropylene resin, and the present invention was completed.

That is, the present invention (A) 80-30% by weight of polyamide resin.

(B) 1 to 40% by weight of modified polyolefin resin and (C
) A polyolefin resin composition is provided in which 5 to 30 parts by weight of (D) polytetrafluoroethylene is blended with 100 parts by weight of a mixture consisting of 20 to 70% by weight of polypropylene resin.

Various types of polyamide resin (A) (hereinafter referred to as component (A)) used in the present invention can be used, but
Specifically, polylactams such as nylon 6, nylon 11°, nylon 12; nylon 66°, nylon 610.
Nylon 612. Polyamides obtained from dicarboxylic acids such as nylon 46 and cyan; nylon 6/66,
Copolymer polyamides such as nylon 6/12° and nylon 6/66/610; nylon 6/6T (T: terephthalic acid component).

Semi-aromatic polyamides obtained from aromatic dicarboxylic acids such as isophthalic acid and metaxylene diamine or alicyclic diamine; mention may be made of polyesteramides, polyetheramides and polyesteretheramides. As the polyamide resin of component (A), the various types of boria 1 mentioned above may be used alone, or two or more types of polyamides may be used in combination.

Furthermore, the polyamide resin that can be used in the present invention is
As long as it is selected from the above-mentioned polyamides, various polyamides can be used without being limited by the type, concentration and molecular weight of the terminal groups of these polyamides. is preferred.

It is also possible to use a polyamide in which low molecular weight substances such as monomers and oligomers that remain or are generated during polymerization of the polyamide are mixed.

(B) modified polyolefin used in the present invention (hereinafter ((
B) Indicated as component. ) as carboxylic acid group (acetate group,
acrylic acid group, methacrylic acid group, fumaric acid group, itaconic acid group, etc.), carboxylic acid metal base (sodium salt, calcium salt, magnesium salt, zinc salt, etc.), carboxylic acid ester group (methyl ester group, ethyl ester group, A polyolefin having at least one functional group selected from a propyl ester group, a butyl ester group, a vinyl ester group, etc.), an acid anhydride group (maleic anhydride group, etc.), and an epoxy group. Examples of the polyolefin include polyethylene, polypropylene, polybutene, and ethylene/propylene copolymer.

Examples include ethylene/butene copolymers, ethylene/hexene copolymers, and copolymers containing a small amount of diene.

Specific examples of such modified polyolefins include ethylene/acrylic acid copolymer, ethylene/methacrylic acid copolymer, ethylene/fumaric acid copolymer, ethylene/methacrylic acid/zinc methacrylate copolymer, and ethylene/acrylic acid copolymer. Acid/sodium methacrylate copolymer, ethylene/
Isobutyl acrylate/methacrylic acid/zinc methacrylate copolymer, ethylene/methyl methacrylate/methacrylic acid/magnesium methacrylate copolymer, ethylene/
Ethyl acrylate copolymer, ethylene/vinyl acetate copolymer, ethylene/glycidyl methacrylate copolymer, ethylene/vinyl acetate/glycidyl methacrylate copolymer, maleic anhydride grafted polyethylene, acrylic acid grafted polyethylene, maleic anhydride Craft polypropylene.

Maleic anhydride grafted ethylene/propylene copolymer, acrylic acid grafted ethylene/propylene copolymer,
Fumaric acid grafted ethylene/1-fudene copolymer, ethylene/l-hexene-itaconic acid copolymer, ethylene/
Propylene-endobicyclo(2,2,1)-5-heptene-2,3-dicarboxylic anhydride copolymer, ethylene/
Propylene-grafted glycidyl methacrylate copolymer.

Maleic anhydride grafted ethylene/propylene/1.4
-Hexadiene copolymer, fumaric acid grafted ethylene/
These modified polyolefins include propylene/dicyclopentadiene copolymer, maleic acid grafted ethylene/propylene/norbornadiene copolymer, and acrylic acid grafted ethylene/vinyl acetate copolymer, and these modified polyolefins may be used alone, or It is also possible to use two or more types together.

The above-mentioned modified polyolefin can be produced by known methods, for example, Japanese Patent Publication No. 39-6810, Japanese Patent Publication No. 4627527, Japanese Patent Publication No. 50-2630, Japanese Patent Publication No. 52-436.
Publication No. 77, Special Publication No. 535716, Special Publication No. 53-
It can be produced according to the methods disclosed in Japanese Patent Publication No. 19037, Japanese Patent Publication No. 53-41173, Japanese Patent Publication No. 569925, etc. Regarding the ethylene ionomer, various grades commercially available under the trade names of "Surlyn", Himilan °°, and "Copolene" ° can be used. In addition, the degree of polymerization of the modified polyolefin used in the present invention is particularly determined. Although there is no restriction, it is possible to arbitrarily select one having a melt index generally within the range of 0.01-100 g/l 0 min.

Next, as the (C) polypropylene resin (hereinafter referred to as component (C)), a propylene homopolymer and/or a propylene copolymer is used. Examples of propylene copolymers include propylene-ethylene copolymers, propylene-butene-1 copolymers, and block copolymers and random copolymers of these copolymers. In addition,
For this polypropylene resin, a propylene homopolymer or a propylene copolymer may be used alone, or two or more types may be used in combination. At this time, the molecular weight of the propylene homopolymer and propylene copolymer is not particularly limited, but generally the melt flow rate (MFR) is 1.
~50g/10 minutes is preferably used.

Furthermore, (D) polytetrafluoroethylene (PTFE)
) (hereinafter referred to as component (D)) is not particularly limited, and various types can be used depending on the required properties and uses of the resulting composition. Preferably, those having a weight average molecular weight of 50.000 to 1,000,000 are used.

In the present invention, the blending ratio of each component for producing a resin composition with excellent friction and wear resistance is (A) polyamide resin in an amount of 80 to 30% by weight, preferably 80 to 40% by weight;
(B) Modified polyolefin is 1 to 40% by weight, preferably 3 to 30% by weight, and (C) polypropylene resin is 20 to 70% by weight, preferably 20 to 50% by weight.

Here, if the (A) polyamide resin is less than 30% by weight,
The friction and wear resistance of the resulting composition is insufficient. 80 on the contrary
If it exceeds the weight percentage, the resulting resin composition will not exhibit the original properties of the polypropylene resin.

Moreover, if the modified polyolefin (B) is less than 1% by weight,
Since it is difficult to improve the compatibility between the polyamide resin as component (A) and the polypropylene resin as component (C), it may not be possible to impart desired physical properties to the resulting composition. On the other hand, (B) modified polyolefin is 4
Even if it exceeds 0% by weight, there is little effect corresponding to the amount blended,
Rather, there is a possibility that the various physical properties of the resulting resin composition may be deteriorated. Furthermore, (C) polypropylene resin is 20% by weight.
If it is less than that, the original characteristics of the polypropylene resin cannot be exhibited. On the other hand, if it exceeds 70% by weight, the intended effect of improving friction and wear resistance will not be sufficiently achieved.

In addition, in the composition of the present invention, (D) PTF which is hi
The blending ratio of E is 5 to 30 parts by weight, preferably 5 to 20 parts by weight, based on a total of 100 parts by weight of components (A), (B), and (C). If the amount of PTFE is less than 5 parts by weight, the desired friction and wear resistance will be insufficient. On the other hand, even if the amount exceeds 30 parts by weight, there will be little effect corresponding to the amount blended, and there is a risk that the physical properties of the resulting resin composition may be deteriorated.

When producing the polyamide polyolefin resin composition of the present invention, (A), (B), (C) and (D)
Melt kneading for tc can be carried out in various conditions. For example, if the polymer is still in a molten state after the polymerization reaction (
A) polyamide resin, (B) modified polyolefin, (
C) polypropylene resin and (D) PTFE may be added and melt-kneaded, or the above (B), (C),
Component (D) may be added and melt-kneaded.

The temperature when melting and kneading each component may be selected as appropriate, but it is usually 180 to 350" C1, preferably 200 to 3
Selected from the range of 00°C. If the temperature is too low, each component will be insufficiently melted, making complete melt mixing difficult, and if the temperature is too high, there is a risk that decomposition reaction will proceed, which is not preferable.

The above-mentioned melt-mixing operation may be performed using a known melt-mixing device such as a single-screw or twin-screw extruder.

The composition of the present invention includes (A) and (B) as described above.

(C) and (D) are mainly composed of tc components,
Depending on the purpose, paint, R material, filler, and nucleating agent may also be added.

Appropriate amounts of fibrous materials, plasticizers, lubricants, mold release agents, coupling agents, foaming agents, heat resistant agents, weather resistant agents, flame retardants, antistatic agents, sliding agents, etc. can also be added.

The composition of the present invention can also be used in pipes and tubes.

It is possible to process it into rods, hollow molded products, injection molded products, etc., and it is also possible to perform plating, painting, etc. as post-processing.

[Examples] Next, the present invention will be explained in more detail based on Examples and Comparative Examples.

The various physical properties of the polyamide/polyolefin resin compositions obtained in the following cases were measured based on the following test methods.

Mukimoto nka & law The test piece is made by screwing the composition It was molded using a molding machine. Siri at this time (A) PA66 as polyamide resin is 280″C, PA6/66 is 265 The temperature was 250″C.The mold temperature was 6. Online shooting temperature is When using "C, PA6 is The temperature was set to 0°C.

A taper wear test was carried out under the conditions of 20"C and 50% RH under a load of 1kg and 1000 cycles using a C3-17 wheel as a mating material.

Friction: 10, gloss: 20''C, under conditions of 250%RH, JISK7218A
The coefficient of dynamic friction was determined by a continuous sliding friction test between cylinder end surfaces in accordance with the method.

In addition, (A) polyamide resin used in each case, (
B) modified polyolefin, (C) polypropylene resin and (D) P T F E are as follows.

A Polymerization ratio: Nylon 6/Nylon 66 = 10 /90 Relative viscosity: 2.90 Amino end group concentration: 4.5 x 10-' equivalent/g (3) Nylon 6 Relative viscosity: 3.10 Amino end group concentration: 4.5 x 10-' equivalent/gB ・
Polyolefin (1) Graft-modified polypropylene I 230" Maleic anhydride was added to a tactical polypropylene having an MFR of 1.0 g/10 min at 0.5 g/min.
Graft-modified polypropylene with 35% addition by weight ■.

(2) Graft-modified polypropylene ■ Maleic anhydride added to tactical polypropylene having an MFR of 1.0 g/10 min at 230°C with 0.7 g of maleic anhydride.
Graft-modified polypropylene with added weight%■.

(3) Ternary modified polyethylene ■ Ternary modified polyethylene I is obtained by copolymerizing 7 parts by weight of methyl methacrylate and 1 part by weight of maleic anhydride to 100 parts by weight of ethylene.

(4) Ternary modified polyethylene ■ Ternary modified polyethylene ■ which is obtained by copolymerizing 9 parts by weight of methyl methacrylate and 3 parts by weight of maleic anhydride to 100 parts by weight of ethylene.

C Propylene, Mu (1) Propylene homopolymer Propylene homopolymer with a VFR of 10 g/10 min according to JIS K 675B (manufactured by Showa Denko ■, Showaromer-M
A510).

(2) Propylene block copolymer A propylene-ethylene block copolymer with an MFR of 16 g/10 min according to JIS K 6758 (manufactured by Showa Denko ■,
Show Aroma-MK511).

(D) Polytetofluoroethylene (PTFE Examples 1 to 12 and Comparative Examples 1 to 4) Pellets of each of the polyamide resin, modified polyolefin, and polypropylene resin shown in Table 1 were added in the predetermined amounts shown in Table 1. After blending and dry mixing for 5 minutes using a Henschel mixer, the resulting mixture was melt-kneaded using a vented co-directional twin-screw extruder (inner diameter 30 m5, L/D=17) to produce pellets.

The heating temperature when making this pellet is 280"C when using nylon 66 as the polyamide resin, PA6
・When using 66, it is 265°C. When using PA6, it is 250.
'C.

The obtained pellets were heated and dried under reduced pressure, and then molded into test pieces (flat plate 100 x 100 x 3.2 m) using an injection molding machine.
m (thickness)), and the friction and wear characteristics were measured.

The results are shown in Table 2.

〔Effect of the invention〕

As explained above, according to the present invention, it is possible to obtain a polyamide/polypropylene resin composition that has both the excellent properties of a polyamide resin and a polypropylene resin, and has particularly excellent friction and wear resistance.

Therefore, the polyamide/polyolefin resin composition of the present invention can be used in automobile parts that require good sliding properties.

Suitable for use in machine parts, industrial parts, etc.

Claims (1)

[Claims] (1) (A) Polyamide resin 80-30% by weight, (B)
Mixture 100 consisting of 1 to 40% by weight of modified polyolefin resin and 20 to 70% by weight of (C) polypropylene resin
A polyamide/polyolefin resin composition containing 5 to 30 parts by weight of (D) polytetrafluoroethylene.