JPH03206602A - Magnetic material 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 magnetic composition, and more specifically, it relates to a magnetic composition that has outstanding impact resistance, adhesion, heat resistance, and water resistance. The present invention relates to a magnetic composition with excellent properties, moldability, flexibility, and electrical properties.

(Prior art and its problems) Sheet-shaped molded products made by injection molding or extrusion molding of compositions in which magnetic powder is mixed into various thermoplastic resins or rubbers exhibit magnetic properties against metals such as iron and nickel. It is widely used in fields such as stationery, electrical appliance parts, and various daily necessities. Among these, magnetic components used at low temperatures, such as magnetic seals on refrigerator doors, and magnetic components used at high temperatures, such as magnets on the front panel of microwave ovens, are used at low temperatures or at high temperatures. Excellent flexibility as well as water resistance are required in applications such as magnetic components for front panels of microwave ovens that are used under harsh conditions, especially at high temperatures. Heat resistance is required.

In order to provide a magnetic composition that satisfies these requirements, the applicant has developed a magnetic composition consisting of poly4-methyl-1-bentene and magnetic powder, and has filed a patent application (patent application). No. 63-266821).

This invention has high levels of physical properties such as adhesiveness, heat resistance, water resistance, and moldability, and can be used in a wide range of applications. In addition to the above physical properties, if a composition with excellent impact resistance at room temperature or low temperature can be obtained,
We got the idea that the uses of this magnetic composition would be further expanded, and based on this idea, we conducted research to obtain a magnetic composition having the above-mentioned physical properties, and as a result, we arrived at the present invention.

(Objective of the Invention) Therefore, an object of the present invention is to create a magnetic material composition that has excellent impact resistance at room temperature or low temperature, as well as excellent adhesiveness, heat resistance, water resistance, moldability, flexibility, and electrical properties. It's about providing things.

(Means for Solving the Problems) The present invention has been proposed to achieve the above object, and is characterized in that specific three component polymers are blended in specific proportions.

That is, according to the present invention, in a magnetic composition containing a resin component and a magnetic powder component, the weight ratio of the resin component and the magnetic powder component (resin component/lit
i-type powder component) is 80/20 to 5/95, and the resin component is fAl40 to 80 parts by weight of poly4-methyl-1-pentene, (B) 20 to 40 parts by weight of a propylene polymer, and (C) a magnetic composition comprising graft-modified poly-4-methyl-1-pentene having 0 to 2 o N parts.

(Description of preferred embodiments of the invention) The poly-4-methyl-1-pentene fA) constituting the resin component in the present invention is a homopolymer of 4-methyl-1-pentene, or a homopolymer of 4-methyl-1-bentene and others. α-olefins such as ethylene, propylene, 1,-butene,
α- having 2 to 20 carbon atoms such as l-hexene, l-octene, l-decene, l-tetradecene, l-octadecene, etc.
It is a copolymer with an olefin, and usually contains 4-methyl-1-pentene in an amount of 85 mol% or more. Poly 4-methyl-1-pentene melt flow rate (MFR, load: 5κg
, temperature: 260°C) is preferably 0.1 to 500g7
10 minutes, more preferably in the range of 0.5 to 150 g and 710 minutes.

In the present invention, the graft-modified poly-4-methyl-1-pentene used as component (C) is the poly-4-methyl-1-pentene described above.
Methyl-1-pentene is grafted with an unsaturated carboxylic acid component or an unsaturated carboxylic acid derivative component as described below.

As poly-4-methyl-1-pentene, which is a raw material for preparing graft-modified poly-4-methyl-1-bentene, the same 4-methyl-i-pentene polymer as described above can be used. However, the intrinsic viscosity [η] (
A 4-methyl-1-pentene polymer having a value measured at 135 DEG C. in a decalin solvent in the range of 0.5 to 25 d/g is preferably used.

Graft modified poly 4-methyl-1- used in the present invention
Pentene has a substantially linear structure and does not have a three-dimensional crosslinked structure. This can be confirmed by the absence of gel-like substances in the solution when the graft-modified poly-4-methyl-1-bentene is dissolved in an organic solvent such as p-xylene.

Graft modified poly 4-methyl-1- used in the present invention
Bentene has a graft ratio of an unsaturated carboxylic acid component or an unsaturated carboxylic acid derivative component in the range of usually 0.5 to 15% by weight, preferably 1 to IO% by weight, and has an intrinsic viscosity [η] (decalin solvent The value measured at 135° C.) is usually in the range from 0.3 to 1Od /g, preferably from 0.5 to 5 d /g.

Graft modified poly 4-methyl used in the present invention -■-
Pentene further has a molecular weight distribution (Mw/Mn) of 1 to 8, a melting point of 170 to 245°C, a crystallinity of 1 to 45%, and a DSC parameter of 4.0 or less. It is preferable that

In addition, the molecular weight distribution f expressed by the weight average molecular weight/number average molecular weight ratio of the graft modified poly 4-methyl-1-bentene
Mw/! Jn) is measured by gel permeation chromatography (GP(1:)).

That is, 0-dichlorobenzene was used as a solvent, and 0.04 parts by weight of graft-modified poly-4-methyl-1-pentene (2.6-parts as a stabilizer) was added to 100 parts by weight of the solvent.
Jeter t. - Add 0.05 parts by weight of butyl-p-cresol to 100 parts by weight of Kraft-modified poly-4-methyl-1-pentene) to make a solution, and then pass it through a filter with a mesh size of 1 μm to remove dust. remove insoluble matter. Thereafter, the column temperature was set to 135°C, and the flow rate was set to l. The above molecular weight distribution (Mw/Mnl) was measured using a GPC measuring device set at omβ/min. The Mw/Mn ratio was determined by converting it into polystyrene paste.

Further, the melting point of the graft-modified poly-4-methyl-1-pentene (sample) is a value measured by a differential scanning calorimeter (OSC), and this melting point is measured as follows. That is, the sample was subjected to a differential scanning calorimeter (du Pont
990 model) and raised the temperature from room temperature at a rate of 20°C/min, and when it reached 250°C, conversely, lowered the temperature at a rate of 20°C/min to 25°C, and then raised it again to 20°C. °C/
Raise the temperature at a rate of 1 minute. The melting point of the material is read from the melting peak value at this time (in many cases, multiple melting peaks appear, so in the present invention, the value on the high melting point side was adopted).

Further, the degree of crystallinity was measured by the following method. That is, using the chart for measuring the melting point by DSC described above, the melting area (Sl
The melting area (SO) on the recording paper corresponding to the melting energy (Po) per unit amount of indium, which is a control sample, is compared. Since the Pa of indium is a known amount, and the melting energy fPl per unit amount of the crystalline portion of poly-4-methyl-1-bentene is also known as shown below, the degree of crystallinity of the measurement sample can be determined by the following equation.

In the formula, Po is 27 Joul/g (atl56±0.5℃
), and P is 141.7 Joul/g. [F.
C. Frank et al. ．． Philosoph
ical Magazine, 4. 200
(195911 also graft-modified poly-4-methyl-1
- The DSC parameter, which is a parameter of the composition distribution of pentene, can be obtained by dividing the melting area (Sl) of the sample measured by DSC by the peak height at the melting point (i.e. maximum peak). Therefore, the DSD parameter is small. It is estimated that the sharper the DSC curve and the narrower the composition distribution.

Graft modified poly(4-methyl) used in the present invention
- The pentene is modified with an unsaturated carboxylic acid component or a derivative component of this unsaturated carboxylic acid. Specifically, unsaturated carboxylic acid components include acrylic acid, maleic acid, fumaric acid, tetrahydrophthalic acid, itaconic acid,
Citraconic acid, crotonic acid, isocrotonic acid, nadic acid 1 (endocysubicyclo[2,2.1]hebuto 5
-en-2,3-dicarboxylic acid), etc., and examples of derivative components of unsaturated carboxylic acids include acid halides, acid amides, acid imides, acid anhydrides, and esters. , maleyl chloride, maleimide, maleic anhydride, citraconic anhydride, monomethyl maleate, dimethyl maleate, glycidyl maleate, and the like are used.

Among these unsaturated carboxylic acids or derivatives of these unsaturated carboxylic acids, unsaturated dicarboxylic acids or their acid anhydrides are preferred, particularly unsaturated dicarboxylic acids such as maleic acid and nadic acid 8, maleic anhydride, anhydride, etc. Unsaturated dicarboxylic acid anhydrides such as nadic acid are preferably used.

Graft modified poly 4-methyl-1- used in the present invention
Pentene can be produced by, for example, dissolving poly4-methyl-1-bentene in a solvent, adding an unsaturated carboxylic acid or its derivative and a radical polymerization initiator to the resulting solution, and heating and graft-modifying the solution ( solution method).

The radical polymerization initiator is usually used in an amount of o. It is used in a proportion of OO to 1 part by weight, preferably 0.0 to 0.5 part by weight. When the modification reaction is carried out in a solution state, the solvent is usually used in an amount of 100 to 100,000 parts by weight, preferably 200 to 10,000 parts by weight, per 100 parts by weight of the poly-4-methyl-1-pentene. used in As for the modification reaction conditions, the temperature is usually 10°C to 250°C, preferably 11°C to 200°C,
The time is usually 15 to 600 minutes, preferably 30 to 60 minutes.

Specifically, the solvent used during the modification reaction is:
Aliphatic hydrocarbons such as hexane, hebutane, octane, decane, dodecane, tetradecane, kerosene, alicyclic hydrocarbons such as methylcyclopentane, cyclohexane, methylcyclohexane, cyclooctane, cyclododecane, benzene, toluene, xylene, Aromatic hydrocarbons such as ethylbenzene, cumene, ethyltoluene, trimethylbenzene, cymene, diisopropylbenzene, halogenated compounds such as chlorobenzene, bromobenzene, 0-dichlorobenzene, carbon tetrachloride, trichloroethane, trichloroethylene, tetrachloroethane, tetrachloroethylene Examples include hydrocarbons. Among these solvents, alkyl aromatic hydrocarbons are particularly preferably used.

Examples of the radical polymerization initiator used in the graft modification reaction include organic peroxides, specifically alkyl peroxides, aryl peroxides, acyl peroxides, aroyl peroxides, ketone peroxides, peroxy carbonates, and peroxides. Oxycarboxylate, hydroperoxide, etc. are used, and more specifically, the following compounds are used.

Examples of alkyl peroxides include diisobrobyl peroxide, di-tert-butyl peroxide, 2.5-
Dimethyl-2,5-di-tert-butylperoxy-hexyne-3, etc. Aryl peroxides include dicumyl peroxide, acyl peroxides include dilauroyl peroxide, and aroyl peroxides include dibenzoyl peroxide. Examples of ketone peroxides include methyl ethyl ketone hydroperoxide and cyclohexanone peroxide, and examples of hydroperoxides include tert-butyl hydroperoxide and cumene hydroperoxide. Among these organic peroxides, di-tert-butyl peroxide, 2,5-dimethyl-2,5-di-tert
-butyl peroxide, dicumyl peroxide, dibenzoyl peroxide and the like are preferably used.

In carrying out the graft reaction, it is preferable to use the unsaturated carboxylic acid or unsaturated carboxylic acid derivative in a proportion of 1 to 40 parts by weight per 100 parts by weight of poly(4-methyl-1-pentene).

In the present invention, the propylene polymer used as the Bl component is a homopolymer of propylene, or propylene and 30% by weight or less of lm or more of other α-olefins, such as ethylene, 1-butene, 1 -hexene,
Block or random copolymer with 4-methyl-1-bentene, etc., or 5% by weight with propylene and ethylene
Contains a multicomponent copolymer with the following polyene components, such as 5-ethylidene-2-norbornene, 5-methylene-2-norbornene, or 1,4-hexadiene, and usually has a melting point of 130°C or higher and a melt flow rate (MFR
) is 0.1 to 80g710min fAsTM D 12
38 L). Among these, a block copolymer of propylene and ethylene is preferred.

The resin component in the magnetic composition of the present invention includes the above-mentioned (Al
The ingredients are 40 to 80 parts by weight, preferably 45 to 7 parts by weight.
0 parts by weight, +20 to 40 parts by weight of component B), preferably 22 to 35 parts by weight, and 20 to 20 parts by weight of component (C), preferably 0.5 to 10 parts by weight. It is.

The fat-loving ingredients blended in such proportions are 80/20 to 5/95, preferably 30/70 to 5/95.
As mentioned above, by mixing with the magnetic powder component described later in the ratio of (resin component/m powder component: weight ratio),
A magnetic composition having excellent impact resistance and well-balanced adhesiveness, heat resistance, water resistance, moldability, flexibility, and electrical properties can be obtained.

The magnetic powder component used in the present invention is an oxide of an iron group element generally called ferrite (molecular formula: MFea04
In the formula, M represents iron and/or an iron group element. ) is used, and specifically, the following ferrites are used.

Mn-ferrite, Ni-ferrite, Zn-ferrite, and solid solutions thereof such as Mn-Zn ferrite, un-Zn-Fe ferrite, Ni-Zn ferrite, Co-Fe ferrite, Ba-ferrite, Sr-ferrite, Formulas that combine rare earth elements in addition to iron group elements, such as Mn-Mg-AI2 ferrite, Cr-ferrite, and other ferrites that have been given various characteristics by adding trace amounts of oxides of various elements to these ferrites. RFeOs
(In the formula, R is Tm, Lu, Yb, Er, Ilo
, Y, Nd, Sm. Represents a rare earth element such as Eu. ) Magnetic materials made of combinations of iron group element oxides that do not contain iron, such as rare earth orthoferrites represented by

The particle size of these magnetic powders is preferably 0.5 to logm, preferably 1 to 5 μm. In particular, the magnetic composition can be extruded using magnetic powder having a particle size of 1 to 5 LLm.

The magnetic composition according to the present invention contains the above-described resin component and magnetic powder component, but in addition to these two components,
If necessary, heat stabilizers may include copper halide compounds, metal soaps, lead stabilizers, organotin stabilizers, epoxy compounds, bisphenol stabilizers, phosphite stabilizers, etc. These may be used alone or in combination of two or more.

In addition, the heat-resistant stabilizer is calculated based on 100 parts by weight of the resin composition.
Usually, it is used in a proportion of 0.1 to 5 parts by weight.

The magnetic composition according to the present invention can be prepared by adding a heat-resistant stabilizer, a lubricant, etc. to the above-described resin component and magnetic powder as needed, and blending the mixture using a Henschel mixer, a V-type blender, or the like. It is obtained by blending using a single screw extruder or a multi-screw extruder.

(Effects of the Invention) The magnetic composition according to the present invention has excellent impact resistance, as well as excellent properties such as adhesiveness, heat resistance, water resistance, and moldability, by being composed of the above-mentioned components. ing.

The magnetic composition according to the present invention takes advantage of the above-mentioned excellent characteristics and is used for applications such as plastic magnets used in rotating equipment, copying machines, sensors, automobile parts, toys, miscellaneous goods, microwave oven parts, etc. It is preferably used for.

(Examples) The present invention will be described below with reference to Examples, but the present invention is not limited to these Examples.

Grafting 4-Methyl-1-pentene homopolymer (intrinsic viscosity [η] 1.7 dl/ g, M./M, ?.5, melting point 24-1°C, crystallinity 42%, DSC parameters 3.
02 or less (sometimes referred to as PMP (I))) was graft-polymerized with maleic anhydride.

A large excess amount of acetone was added to the solution containing the graft polymer thus obtained to precipitate the graft polymer.

This graft polymer was separated by filtration, and the separated graft polymer was washed repeatedly with acetone to obtain maleic anhydride graft-modified poly-4-methyl-1-pentene A (hereinafter sometimes referred to as MAH-PMPfAl). Obtained.

This maleic anhydride graft-modified poly-4-methyl-1-
The grafting ratio of maleic anhydride units in bentene A was 4.0% by weight, the intrinsic viscosity [η] was 0.95 dl/g, the melting point was 210°C, the crystallinity was 18%, M = /M. is 4.
5. DSC parameter was 2.8.

Ferrite, a magnetic powder material (average particle size 1.18u)
m, compressed density 3.25g/cm'. 100 parts by weight of OP-711 manufactured by Nippon Bengara Kogyo ■ was added with 1 liter of surface treatment agent (Blen Act J KR-TTS, manufactured by Ajinomoto ■).
Ferrai 1 was previously surface-treated using the following amounts: parts by weight.

75 parts by weight of the above-mentioned PMP (1) and a crystalline propylene/ethylene block copolymer (ethylene content: 20% by weight, MFR: 0.5g710min, density = 0.
91 g/cc) 20 parts by weight and the M A H
- A resin composition consisting of 5 parts by weight of P M P (A) (
(hereinafter sometimes abbreviated as modified PMP-1) and the above ferrite were blended in the weight ratios shown in Table 1, respectively.

To 100 parts by weight of the above modified PMP-1, Irganoxl010 (Ciba Geigy ■
) 2 parts by weight and Seenox 4 1 as the same heat-resistant stabilizer.
2 S [PenLa (erysrythyl-t
etra-β-mercap trauryl pro
1 part by weight of Pionate (manufactured by Cipro Kasei) was added.

Next, a blend consisting of the modified PMP-1, ferrite, and heat stabilizer was mixed in a Henschel mixer and formed into pellets in a twin-screw extrusion mill. Next, using an injection molding machine, test pieces for the following items were prepared from this pellet, and each item was measured.

(11 heat aging test; l20mmX l50
A square plate of mm×2+nmt was prepared, and then placed in an air oven set at 160° C. and left for 5 days, and the deterioration state, deformation, and melting state of the test piece were visually observed and evaluated.

(Evaluation method) ○: No problems with deterioration, deformation, and melting changes Δ: Some deterioration ×: Significant deterioration, deformation and melting +21 fI=t Boiling water test; A test piece similar to the above (11 test) was prepared. The test piece (square plate) was immersed in boiling water at 100° C. for 1 day, and the dimensional properties of the test piece (square plate) were measured.

(Evaluation method) ○: Dimensional change of less than 1.0% Measurements were made in accordance with ASTM 0256 in an atmosphere of 100°C.

(4) Tensile test; using an injection molding machine, ASTM0638
A test piece according to the above was prepared, and the elongation rate was measured in an atmosphere at 23°C.

(5) Chemical resistance test: From the square plate shown in (1) above, 2
A test piece measuring 0mm x 40mm x 2n+mt was cut and left immersed in 98% sulfuric acid at a temperature of 25°C for 7 days, and the change in weight of the test piece was measured.

(Evaluation method) ○: Dimensional change less than 1.0% x: i. Dimensional change of 0% or more The results obtained are shown in Table 1.

4-methyl-l-pentene-decene copolymer (PMP-D) with an MFR of 0.5 g for 710 minutes (260°C, 5 kg load)
The same heat-resistant stabilizer as in Example 1 was added to 100 parts by weight (abbreviated as ), and the above ferrite was blended in the amount shown in Table 1.

Next, a mixture of PMP-D, ferrite, and heat stabilizer was mixed in a Hensel mixer, and formed into a pellet in a twin-screw extrusion mill. Next, using an injection molding machine, test pieces similar to the test pieces for each test item in Actual Example 1 were made from this pellet, and tested for heat aging resistance, boiling water resistance, Izod impact strength, tensile test, and chemical resistance. Tests and the like were conducted as described in Example 1.

The results obtained are shown in Table 1.

Comparative Example 1 The same heat-resistant stabilizer as in Example 1 was added to 100 parts by weight of nylon 6 (manufactured by Unitika ■: Al020BRL grade) having an MFR of 43 g/to min (235°C, lkg load), and the above ferrite was added. were blended in the amounts shown in Table 1.

The blend of nylon, ferrite, and iFl heat stabilizer was then mixed in a Hensel mixer and pelletized in a twin screw extruder. Next, using an injection molding machine, test pieces for each test item of Example 1 were prepared from the pellets, and the test pieces were tested according to the method described in Example 1.

The results obtained are shown in Table 1.

Anonymous Alliance Yu

Claims (1)

[Claims] (1) A magnetic composition containing a resin component and a magnetic powder component, wherein the weight ratio of the resin component to the magnetic powder component (resin component/magnetic powder component) is from 80/20 to 5/95, and the resin component (A) 40 to 80 parts by weight of poly-4-methyl-1-pentene, (B) 20 to 40 parts by weight of a propylene-based polymer, and (C) 0 to 20 parts by weight of graft-modified poly-4-methyl. - A magnetic composition comprising 1-pentene.