KR910010024B1 - Containing polyacetal resin composite composition excellent in rigidity - Google Patents

Abstract

The oil-containing polyacetal resin complex compsn. comprises 5-100 wt. pts. magnesium oxysulphate of inorganic high-strength single crystalline fiber whisker type having 1 m diameter and at least the aspect ratio, 1-40 wt. pts. of the lubricating oil, with 100 wt. pts. of the polyacetal resin. Pref. the polyacelal resin is homopolymer, copolymer or tricopolymer having the repeating gp. of oxymethylene group (-OCH2-). Pref. the lubricating oil is the paraffinic, naphthanic, mineral oil or the synthetic oil, e.g. grease, hydrocabon, ester, polyglycol, polyphenyl ether, silicone or halocarbon.

Description

Containing polyacetal resin composite composition excellent in rigidity

The present invention relates to an inorganic high strength single crystal fiber Whisker reinforcement-containing polyacetal resin composition having excellent rigidity and abrasion resistance and having a smooth surface appearance.

Background Art Conventionally, a method of incorporating various lubricants for the purpose of imparting lubricity and wear resistance to resins has been studied. Especially, the method of mixing lubricating oil is known to have a remarkable effect in the point which improves abrasion resistance at high speed and high load. Adding oil to such resins is not so easy and requires additional equipment such as a special oil adder or other techniques.

However, none of the prior art has many drawbacks, and there is not much satisfactory practically. For example, Japanese Patent Publication No. 67-21786 shows a composition for a water repellent material in which petroleum lubricant or synthetic lubricant is added to ultra high molecular weight polyethylene, and Japanese Patent Publication No. 72-41092 shows an ester lubricant in a polycarbonate resin. The composition to which is added is shown. However, because of the relatively high affinity between ultra high molecular weight polyethylene and petroleum-based or synthetic lubricants, in order to significantly improve the lubricity, mixing of a large amount of lubricant oil is considerably lowered in rigidity and flexible, so that it is required for practical use. There is a drawback that cannot be used, and there is a drawback that the surface becomes wet because the added lubricant seeps out.

In addition, polyacetal, polyamide, or polycarbonate resins have little affinity with lubricating oils, making it difficult to incorporate a large amount of lubricating oils. For example, even if a large amount of lubricating oil is mixed by using a special apparatus or method, the surface is wet because the lubricating oil is severely separated and exuded. In addition, since the mold is contaminated at the time of molding using a general screw-type injection molding machine, an extrusion molding machine or the like, it is difficult to obtain a molded article having good dimensional stability and excellent surface and appearance.

In order to eliminate this drawback, the addition of a third material has been examined in various ways, but none of them have been satisfactorily practical to date. For example, Japanese Patent Publication No. 43-4634 describes a method for adding a room temperature solid lubricant and graphite or carbon fine powder to a polyamide synthetic resin, and Japanese Patent Publication No. 73-37571 includes lubricant in graphite. The composition which mix | blended the mixed mixture with the thermoplastics is shown. However, since solid additives such as carbon fine powder and graphite have a small ability to hold the lubricant, when a large amount of lubricant is added for the purpose of providing sufficient lubricant, the lubricant is often separated and exuded from the molded product. Will get wet. Japanese Patent Publication No. 72-29374 discloses a composition obtained by adding a lubricating oil to an ultra high molecular weight polyethylene to a synthetic resin material. However, since lubricating oil is mixed with ultra high molecular weight polyethylene, it is difficult to disperse lubricating oil during melt mixing, extrusion and molding by adding it to a synthetic resin material as it is because of its low fluidity.

For this reason, a method in which ultra-high molecular weight polyethylene is made into a fine powder and lubricating oil is mixed and then added to the synthetic resin material or the lubricant is absorbed into the ultra-high molecular weight polyethylene and then pulverized and added to the synthetic resin material is considered. However, even by such a method, since the particle diameter of the ultrahigh molecular weight polyethylene dispersed in the synthetic resin material does not become smaller than the particle size of the powdery phase before addition, it is difficult to produce a resin material dispersed in the ultrahigh molecular weight polyethylene including the lubricant highly uniformly. Therefore, it is difficult to obtain a molded article having excellent dimensional stability and good surface appearance, and also difficult to manufacture films, fibers and the like.

In addition, Japanese Patent Publication No. 73-37572 discloses adding saturated or unsaturated higher fatty acids, their salts, esters, amides, chlorides, metal soaps, and the like as fourth components in order to improve wear resistance of Patent Publication No. 72-29374. Although a composition is shown, it is also difficult to solve the said fault by this.

In addition, other methods of blending the ethylene absorbs the hydrocarbon-based lubricant and the lubricant in the copolymer using the (Japanese Patent Publication No. 71-55677 No.), the lubricating oil and barium sulfate BaSO ₄ or less by volume of the 3.5 (BaSO ₄₎ in the absorbent (Japanese Patent Publication No. 77-1932) and a method of absorbing lubricating oil to a polynorbornene elastomer to add an inorganic filler and a solid lubricant (Japanese Patent Publication No. 84-179660-3). Even if the problem mentioned is solved, there is a drawback that it does not have good surface appearance and sufficient rigidity as a wear resistant water-repellent product.

Accordingly, the inventors of the present invention have repeatedly studied to solve the above-mentioned shortcomings. As a result, the fibrous magnesium oxysulfate is a highly sensitive single crystal fiber whisker of inorganic material having excellent oil absorption with polyacetal resin and having an aspect ratio of 40 or more. (MgSO ₄ , 5MgO, 8H ₂ O or basic magnesium sulfate) Absorbs lubricating oil into the reinforcing agent and has excellent rigidity and wear resistance prepared by blending with polyacetal resin at a temperature above the polyacetal resin melting point, preferably 170 to 210 ° C. The present invention relates to a polyacetal resin composition having a good surface appearance and a method for producing the same.

That is, the first object of the present invention is an inorganic oil having excellent oil absorption with respect to 100 parts by weight of a polyacetal resin (hereinafter also referred to as "(a) component"), having a particle diameter of about 1 μm, and having an aspect ratio of 40 or more. Magnesium oxysulfate on high strength single crystal fiber whisker [hereinafter also referred to as "b" component] 5 to 100 parts by weight and lubricating oil added to improve wear resistance and lubricity [hereinafter also referred to as "(multi) component"] It is a containing polyacetal resin composite composition characterized by comprising 40 core parts.

Also, the second object of the present invention is to hensel a magnesium oxalate fiber whisker and a lubricant having high oil absorption with polyacetal resin to facilitate the addition of lubricating oil to the polyacetal resin and to improve wear resistance and rigidity of the polyacetal resin. Polyacetal with good rigidity and good surface appearance, characterized in that the lubricating oil is sufficiently absorbed by mixing (Henschel mixing), and then kneaded at a temperature above the melting point of the polyacetal resin, preferably in the temperature range of 170 to 210 ° C. It relates to a method for producing a resin composition.

The polyacetal resin of the (A) component used in the present invention is already widely commercialized and known as being useful as a molding, and is also called polyoxymethylene (POM). This resin is classified into homopolymers, copolymers, terpolymers, etc., in which oxymethylene groups such as -OCH ₂ -groups are repeated.

)을 들 수 있다.In general, homopolymers are prepared by polymerization of anhydrous formaldehyde or polymerization of trioxane, a cyclic trimer of formaldehyde, usually stabilized by endcapping against pyrolysis. Delrin (Delrin) of the United States of America in the brand name ) And Tenac of Asahi Chemical Company, Japan

).

Particularly suitable polyacetal copolymers which can be used in the molding compositions of the present invention are 0.1 to 20 parts by weight of an inert organic solvent per 100 parts by weight of formaldehyde, cyclic formal, formaldehyde, as shown in Korean Patent Publication No. 86-674. It is possible to feed continuously to the twinaxial mixer, in which formaldehyde is copolymerized with cyclic formals in the presence of boron trifluoride or an ether complex thereto.

The water content of formaldehyde used in the present invention is less than 0.1% by weight, particularly preferably less than 0.01% by weight, and the formaldehyde is reacted in a gaseous state.

A compound of the general formula

A compound of formula

Is used as cyclic formal in the present invention. The above general formula R ¹ , R ² , R ³ , and R ⁴ are each a hydrogen atom or a hydrocarbon, preferably an alkyl group having 1 to 8 carbon atoms, an aryl group having 6 to 10 carbon atoms, or a cyclo having 5 to 7 carbon atoms. An alkyl group, m represents an integer of 1 to 3, n represents an integer of 2 to 6; Specific examples include ethylene oxide, propylene oxide, butene-1-oxide, 1,3-butadiene-1-oxide, styrene oxide, α-methylstyrene oxide, oxerane, tetrahydrofuran, 1,3-dioxolane, 4-phenyl-1,3-dioxolane, 1,3,6-trioxocane, 1,3,5-trioxocane and polyethylene glycol formal are mentioned. The amount of cyclic formal used is preferably 0.001 to 0.1 moles, more preferably 0.01 to 0.04 moles per mole of formaldehyde supplied. At ordinary temperatures, it is preferable to preheat the cyclic ether, which is a liquid, to use the reaction in the gaseous state.

The polyacetal copolymer used in the present invention is prepared by the above method, and uses 80 to 95 parts by weight of a melt index of 9.0 g / 10 min measured by the ASTM D1238-82 method.

), 독일 훽스트사의 호스타포름(Hostaform

), 바스프시의 울트라포름(Ultraform

), 일본 미쓰비시가스사의 유피탈(Iupital

), 폴리플라스틱사의 듀라콘(Duracon

), 당사의 루셀(LUCEL

) 및 한국 엔지니어링 플라스틱사의 케피탈(Kepital

) 등을 들 수 있다.In addition, the name of the polyacetal copolymer that can be used is Celcon of Celanese Corp. of the United States.

), Hostaform of Hoechst, Germany

), Ultraform (Ultraform of BASF city)

), Japan's Mitsubishi Gas Corporation

), Duracon from Polyplastics

), Our LUCEL

) And Korea Engineering Plastics Co., Ltd.

), And the like.

The polyacetal terpolymer reacts with trioxane and cyclic ethers and / or cyclic acetals, as is known, in the preparation of polyacetal copolymers, with a third monomer which is a bifunctional compound such as diglycidide Can be prepared.

) U10을 들 수 있다.Wherein Z represents oxyalkoxy, which may be a carbon-carbon bond, an oxygen atom, 1-8 carbon atoms, preferably 2-4 carbon atoms, or oxycycloalkoxy of 4-8 carbon atoms, preferably each Oxy-poly (lower alkoxy) of 2-4 repeating groups having 1-2 carbon atoms. A commercially available polyacetal terpolymer is Celel's Celcon.

) U10 can be mentioned.

)를 들 수 있다.The fibrous magnesium oxysulfate whisker of (b) component used in the present invention is a kind of inorganic high strength single crystal fibrous whisker, and is widely used as a reinforcing material and asbestos substitute of plastic, and the molecular formula is MgSO ₄ , 5MgO, 8H ₂ O. Magnesium oxysulfate whisker used in the present invention has excellent oil absorption, particle diameter of about 1μm, aspect ratio of 40 or more, specific surface area (BET method) is 10m ² / g or less, needle (針狀) White powder with crystalline form. As a fibrous magnesium oxalate whisker used in the present invention, Mos-Hige was developed in Wubaeheungsan, Japan.

).

The lubricating oil for improving the wear resistance and lubricity of the (multi) component used in the present invention is a paraffinic, naphthenic, mineral oil and grease, hydrocarbon, such as spindle oil, refrigerator oil, dynamo oil, turbine oil, machine oil, cylinder oil, gear oil, The synthetic synthetic oils such as esters, polyglycols, polyphenylethers, silicones, and halocarbons can be widely selected and used.

According to the object of the resin composition of the present invention as described above, a small amount of a release agent, an antioxidant, a formaldehyde and a formic acid scavenger, a heat stabilizer, an ultraviolet stabilizer, a foaming agent, an antistatic agent, a dye, a dye, and the like can be used. Hereinafter, the present invention will be described in detail with reference to the following examples.

Example 1

; M.I =9g/10min] 100중량부에 대하여, 마그네슘 옥시설페이트 위스커(일본 우베흥산제품, Mos-Hige) 15중량부 및 윤활유(SAE #30 엔진오일) 10중량부를 첨가하여, 윤활유가 위스커에 충분히 흡수되어 골고루 분산될 수 있도록 4분동안 헨셀믹싱(Henschel Mixing)한 후, 니더(Kneader)를 사용하여 실린더 온도를 200℃로하여 압출한 후, 이를 펠렛상으로 만든다.Polyacetal copolymer [Lucky Co., Ltd., LUCEL N-109

; MI = 9 g / 10 min] With respect to 100 parts by weight, 15 parts by weight of magnesium oxysulfate whisker (Mos-Hige manufactured by Ubeheung, Japan) and 10 parts by weight of lubricating oil (SAE # 30 engine oil) are added, so that the lubricating oil is sufficiently absorbed by the whisker. After 4 minutes Henschel mixing (Henschel Mixing) to be evenly dispersed, using a kneader (Kneader) to extrude the cylinder temperature to 200 ℃, which is made into a pellet.

To measure the friction coefficient, flexural strength, and flexural modulus, the pellets were first dried for 3 hours using a dehumidifying dryer or a hot air dryer at 80 ° C. do.

Table 1 shows the results of measuring and comparing the physical properties of the specimens prepared as described above according to ASTM.

Example 2

Except for adding 30 parts by weight of magnesium oxysulfate whisker (manufactured by Ubeheungsan ^, Japan, Mos-Hige) ^, it was made into pellets by reacting with the same composition and composition ratio as in Example 1, and a specimen was prepared to prepare a specimen and The same was measured. The results are shown in Table 1.

Comparative Example 1

With respect to 100 parts by weight of the same polyacetal copolymer as in Example 1, 10 parts by weight of the same lubricating oil as in Example 1 was added and extruded into a pellet form using a special liquid adding device at a cylinder temperature of 200 ° C. using a kneader. Make.

In order to determine the friction coefficient, flexural strength, and flexural modulus for this, the same specimens as in Example 1 were prepared, and the physical properties thereof were measured.

TABLE 1

EXAMPLES 3 AND 4

)및 폴리아세탈 삼원공중합체(셀라니즈 상 제품, Celcon U10-01

) 100중량부에 대하여 실시예 1과 동일한 양의 위스커 및 윤활유를 첨가하여 동일한 방법으로 시편을 만들어 물성을 측정한 후, 이에 대한 결과를 표 2에 나타내었다.Polyacetal Homopolymer from DuPont, Delrin 500

) And polyacetal terpolymers (from Celanese Phase, Celcon U10-01

) 100 parts by weight of the same amount of whisker and lubricating oil as in Example 1 was added to make a specimen in the same manner to measure the physical properties, and the results are shown in Table 2.

Comparative Examples 2 and 3

10 parts by weight of the same lubricating oil as in Example 1 was added to the same polyacetal homopolymer and terpolymer 100 parts by weight of Example 3 and 4 using kneader, and then lubricating oil was added and extruded in the same manner as in Comparative Example 1 to measure physical properties. Table 2 shows the results compared with Examples 3 and 4.

TABLE 2

Claims (3)

Containing polyacetal resin, characterized in that it consists of 5 to 100 parts by weight of inorganic high-crystal single crystal fiber whisker-like magnesium oxysulfate and about 1 to 40 parts by weight of lubricating oil with respect to 100 parts by weight of polyacetal resin, having a particle diameter of about 1 μm and an aspect ratio of 40 or more. Composite composition. The polyacetal resin composite composition according to claim 1, wherein the polyacetal resin is a homopolymer, a copolymer, or a terpolymer by repeating an oxymethylene group (-OCH _2- ). The lubricating oil according to claim 1, wherein the lubricating oil is a paraffinic, naphthenic, mineral oil and grease, hydrocarbon, ester, polyglycol, polyphenyl ether, such as spindle oil, refrigerator oil, dynamo oil, turbine oil, machine oil, cylinder oil, gear oil, etc. Polyacetal resin complex composition containing an artificial synthetic oil, such as silicone, halocarbon.