KR100391012B1 - Elastomeric paint compostion having low friction and high heat resistance - Google Patents

Abstract

The present invention is a micro-silicone coating using an alkoxide sol-gel method. The present invention provides an inorganic binder (sol-gel alkoxide) that is different from the conventional binder system, and has high heat resistance (300 ° C.), low friction (μ: 0.1 or less) and rubber elasticity to be used as a high quality micro-silicone paint. In addition, the present invention is to facilitate the development of ultra-high temperature paints and coatings by providing a new inorganic binder. The present invention 60 to 85 parts by weight of the paint base; 131 to 141 parts by weight of methyltrimethoxysilane (MTMS), 100 to 118 parts by weight of isopropyl alcohol (IPA), 17 to 36 parts by weight of water, 0.25 to 0.29 parts by weight of hydrochloric acid (HCl 13.6%) by sol-gel method 20 to 25 parts by weight of an alkoxide inorganic binder brush obtained by condensation; Triphenylmethane 4,4,4-triisocyanate is a low friction heat-resistant elastic paint prepared by including 2 to 8 parts by weight.

Description

Elastomeric paint compostion having low friction and high heat resistance}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a low friction super heat resistant elastic coating, and more particularly, to an elastic coating and a composition thereof that can be used as a coating material for micro-seal composition of metal gaskets.

Paints and coatings having low friction, heat resistance and elasticity are industrially used. These materials are made of thermosetting resins, that is, paints based on thermosetting resins such as epoxy, phenol, unsaturated polyester, melamine, polyurethane, and polyamide are used as heat-resistant paints or heat-resistant coatings, and rubber-based materials. In other words, paints using fluorine rubber, silicone rubber, acrylic rubber, etc. are used as heat-resistant paints and elastic paints. In addition, paints made of thermoplastic resins such as PTFE, nylon, thermoplastic polyester, and TPE are heat-resistant paints. Has been used.

The thermosetting resin heat-resistant paint is a two-component or three-component paint, has a problem such as a pot life, such as a pot life and has a high heat resistance, but lacks low friction characteristics, and the thermoplastic resin heat-resistant paint can be made into a one-component type, but lacks adhesive strength. And heat resistance, in particular, the lack of hot heat resistance, and can not be used as a super heat-resistant paint stable above 200 ℃, rubber-based heat-resistant paints have heat resistance and elastic properties, but low friction properties and there is a limit to increase the hardness of the surface It was to lower the sealing characteristic.

Gaskets for preventing leakage of automotive, land and marine engine lubricating oils are provided with a 7-15 μm thick micro-seal layer to maintain the sealing force on the contact surface of the metal plate.

In order for the gasket to maintain an excellent sealing force as an engine part, the micro-seal must simultaneously have low friction, stable heat resistance to temperatures higher than 200 ° C, rubber elasticity, water resistance and resistance to engine coolant, and It must also have mechanical durability to withstand.

As such, the properties that micro-seals must have at the same time are different from those of conventional simple heat-resistant paints. Therefore, when developing micro-seals based on conventional heat-resistant paints, consideration for imparting the above characteristics to the composition of the paints is considered. It must be included.

Conventionally, the three-component paint mainly composed of epoxy and the two-component paint mainly composed of epoxy are used for the paint for the micro-seal composition applied to the engine metal gasket for automobile and marine applications. The lack of elasticity and the three-component type make it inconvenient to use, and the rubber-based paints exhibit functional defects such as high frictional resistance, low surface hardness, and large difference in adhesive strength depending on the material of the adherend. 8-113755 is known a coating composition consisting of alkoxysilane partial hydrolysis condensates such as fluorine-based copolymers, methyltrimethoxysilane, organic solvents, isocyanate-based curing agents, etc., but it is stain-resistant (low friction coefficient of fluorine paint). To reduce the pollution from the outside by improving the prevention of pollution using No. 7-109435 discloses an outdoor article having a thin film comprising an organic solvent such as isopropyl, a hydrolyzate of a silane compound partially condensed by hydrochloric acid in a mixed solvent with water, and a synthetic resin isocyanate-based curing agent such as fluororesin. However, this was to prevent the contamination of the paint from the outside using the friction and contact angle of the cone fluorine compound to prevent the contamination was not able to obtain the low friction ultra heat resistance and elastic properties.

SUMMARY OF THE INVENTION An object of the present invention is to propose an elastic coating composition exhibiting the function of micro-seal having both elasticity of rubber, ultra heat resistance and low friction. The purpose is to suggest.

Specifically, the present invention is a one-component or two-component paint using an alkoxide-based sol as a binder of the paint, and exhibits strong adhesion, low friction, and low viscosity (50 cps, Brookfield) characteristics, thereby providing The thin film coating layer can be stably maintained, so that the thin film coating layer can be used as a coating material for micro-seal composition of automobile and land and marine engine gaskets.

1 is a cross-sectional view of the reactor of the present invention.

The present invention will be described in detail as follows. The present invention includes 60 to 85 parts by weight of paint base; 131 to 141 parts by weight of methyltrimethoxysilane (MTMS), 100 to 118 parts by weight of isopropyl alcohol (IPA), and water. 20 to 25 parts by weight of an alkoxide inorganic binder sol obtained by hydrolysis and condensation of 17 to 36 parts by weight and 0.25 to 0.29 parts by weight of hydrochloric acid (HCl 13.6%) by a sol-gel method; triphenylmethane 4,4,4-tri as a crosslinking agent; It is a low friction heat-resistant elastic coating prepared by containing 2 to 8 parts by weight of isocyanate. The present invention is a composition of the inorganic binder by the sol-gel method in order to impart super heat resistance, low friction and rubber elasticity to the paint. In the present invention, the inorganic binder is one of the adhesive components of the paint, and is mixed with the bases 1, 2 and 3 of the prepared paint, respectively, to become a super heat-resistant elastic paint. Hydrochloric acid contained in the inorganic binder is involved in controlling the performance and yield of the inorganic binder as a hydrolyzing agent for promoting hydrolysis. In addition, since the sol-gel binder reacts quickly and sensitively, the input amount of the material is limited as described above. The present invention uses a base of fluororubber and bisarylnadicimide for ultra heat resistance, low friction, and rubber elasticity. Polyisoprene is added to reinforce the rubber elasticity.

The present invention reduces the difference in the adhesive strength to the adherend by using a brush using an alkoxide having a small variation in the adhesive strength according to the type of metal as a binder of the paint.

The paint base in the composition of the present invention is an adhesive mixture that exhibits low frictional properties by forming heat resistance and hard surfaces, and reducing the composition ratio decreases the adhesiveness and the low frictional property, and increases the composition ratio to increase the modulus of elasticity. Is an agent to increase adhesion and heat resistance. Reducing the composition ratio decreases the adhesive strength, and increasing the composition ratio decreases the elasticity and costs. The crosslinking agent decreases the composition ratio, decreases the physical properties, and increases the composition ratio, the coating layer becomes hard.

Hereinafter, the present invention will be described in detail.

1. Preparation of Inorganic Binder

The present invention used the reactor of Figure 1 to obtain a sol binder.

An embodiment of the preparation of the sol binder (binder 3) using the reactor of FIG. 1 is as follows. 136 g of methyl trimethoxysilane (MTMS) and 117.96 g of isopropyl alcohol are added thereto to change the internal temperature of the reactor to reflux 70 to 70 ° C. It heats up to 80 degreeC.

While maintaining reflux temperature, 17.77 g of water and 0.27 g of hydrochloric acid (13.6%) are added dropwise and mixed.

When the reaction is carried out for 2 hours while maintaining the reflux temperature, the hydrolysis is completed and the alkoxide molecules are maintained as sol as nSiO ₂ particles. In the present invention, the sol is referred to as a binder.

The binder is a main component of the paint, and when heated to 150 ~ 220 ℃ is concentrated in a gel state, has a strong adhesion to glass, iron plate, ceramics, etc., to form a thin film on the surface of the adherend, the formed thin film The film exhibits super heat resistance.

In the inorganic binder of the present invention, binder 1, binder 2, and binder 3 may be manufactured by varying the mixing ratio of materials as follows.

Binder 1, 2, 3 Blending Weight Ratio Material Binder 1 Binder 2 Binder 3

Methyltrimethoxysilane (MTMS) 136 136 136

Isopropyl Alcohol (IPA) 100 108.7 117.96

Water 35.17 26.77 17.77

Hydrochloric acid (HCl 13.6%) 0.27 0.27 0.27

Total 272.24 271.74 272.00

When the compounding ratios of the binder 1, binder 2, and binder 3 materials are converted into equivalent ratios, they are shown below.

Equivalent compounding ratio of binder 1, 2, 3 composition

Material Binders1 Binders2 Binders3

Water / MTMS (r) 2/1 1.5 / 1 1/1

MTMS / IPA 1 / 1.67 1 / 1.81 1 / 1.97

MTMS / HCl 1 / 0.01 1 / 0.01 1 / 0.01

NV (%) 50 50 50

Response time 2 hours 2 hours 2 hours

Reaction temperature reflux reflux reflux

PH 3 4 5

Appearance Slightly cloudy Transparent Transparent

2. Manufacture of paint base

The paint base is produced in the following steps.

Step 1: In step 1, the polymer component of the paint and the filler are kneaded in a roll or a mixer to obtain an elastic mixture for rubber elasticity and heat resistance of the base 1.

The material and mixing ratio of base 1 are as follows.

<Base1>

50 to 60 parts by weight of FKM (fluorine rubber);

20-30 parts by weight of HAF (carbon black);

0.1 to 1 part by weight of stearic acid;

2 to 4 parts by weight of triallyl isocyanurate;

10-15 parts by weight of barium sulfate;

0.2 to 1 part by weight of vinyl-tris (β-methoxy-epoxy) silane;

2-4 parts by weight of dicumyl peroxide (40%);

The material was kneaded in a mixer or roll to obtain an elastic mixture for rubber elasticity and heat resistance.

Step 2: In step 2, the mixture of base 1 is dissolved in a solvent and primary paints as with base 2.

The primary paint of step 2 is the same as base 2.

<Base2>

40 parts by weight of the mixture of base 1,

Dissolved in 60 parts by weight of solvent methyl isobutyl ketone (MIBK),

The mixture of base 1 is primaryized.

Step 3: In step 3, the mixture of base 2 and the material containing bisallynalididem (available at 300 ° C.) are mixed to obtain super heat and low friction properties (such as forming a hard surface) such as base 3. Eggplant prepares a mixture.

Elastic paints with super heat resistance and low friction are the same as for base 3.

<Base3>

60 to 70 parts by weight of the mixture of Base 2;

10-15 parts by weight of bisallynadic imide;

5-10 parts by weight of blocked isocyanate (D-550 manufactured by Aekyung Chemical Co., Ltd.);

Modified polyurethane (EFKA-4015 manufactured by Aekyung Chemical Co., Ltd.) 0.5 to 1 part by weight;

Modified polyurethane (manufactured by EFKA-65 Aekyung Chemical Co., Ltd.) 0.5 to 1 part by weight;

5 to 10 parts by weight of modified isoprene rubber (manufactured by LIR Japan KURARAY Co., Ltd.);

Methyl isobutyl ketone (MIBK) 4 to 10 parts by weight;

By mixing the elastic coating of the base 3 having a super heat resistance characteristics, low friction characteristics.

3. Manufacturing of ultra heat-resistant elastic paint

Super heat-resistant elastic paint,

80 parts by weight of the mixture of base 3;

16 parts by weight of the binder;

4 parts by weight of triphenylmethane 4,4,4-triisocyanate;

The superheat resistant paint of the present invention was prepared by the formulation of.

The present invention can be used as a one-part type as described above, and may be used as a two-part type when the viscosity of the user needs to be adjusted according to the conditions of the use site.

* Example

The materials of steps 1, 2, and 3 described below are treated as described above to obtain a paint base.

Example Step 1:

Material compounding quantity (weight part)

FKM 58.88

HAF 23.43

Stearic Acid 0.12

TAIC 2.34

BaSO ₄ 11.72

Vinyl-tris (β-methoxy-epoxy) silane 0.59

Dicumyl peroxide (40%) 2.92

Total 100

Example Step 2:

Material compounding quantity (weight part)

EXAMPLES Mixture of Step 1 40

Methyl Isobutyl Ketone 60

Total 100

Example Step 3:

Material compounding amount (part by weight) Remarks

Example Mixture 66 of Step 2

Modified Isoprene Rubber 6.20 LIR

Bisarylnadic imide 12.68

Blocked Isocyanate 5-10 D-550 (HDI)

Modified Polyurethane 0.8 EFKA-4065

Modified Polyurethane 0.5 EFKA-65

Methyl Isobutyl Ketone 7.14

Total 100

The following materials are treated as described above to obtain a binder.

Material compounding quantity (weight part)

Methyltrimethoxysilane 65.79

Ethyl alcohol 22.35

Distilled Water 11.83

HCl 0.03

Total 100

Manufacture of Heat Resistant Elastic Paint of the Invention

Material compounding quantity (weight part)

Example Mixture 80 of Step 3

Example Alkoxide Inorganic Binder 16

Triphenylmethane 4,4,4-triisocyanate 4

Total 100

Test results of the low friction ultra heat-resistant elastic coating obtained in the above embodiment are shown in Table 1.

Table 1:

Item Test Result Remarks

Viscosity (cps, 25 ° C) 7000-8000 Brookfield Viscometer

Specific gravity (20 ℃) 1.018 ± 0.05 Specific gravity cup method

Coolant resistance (105 ℃ × 72hr) 100/100, no abnormality Cross cut method

Friction coefficient (μ) 0.1 or less Static friction test

Heat resistance (300 ℃ × 4hr, left) No change in appearance

Water resistance (25 ℃ × 1 week) no change in appearance

Substrate: SUS304

Curing condition of paint:

1st 80 ℃ × 1min

2nd 200 ℃ × 90min

As described above, the micro-silicone paint of the present invention using the alkoxide sol-gel method provides an inorganic binder (sol-gel alkoxide) different from the conventional binder system, thereby providing ultra heat resistance (300 ° C.) and low friction (μ: 0.1 or less) and rubber. It can be used as a high-quality micro-seal composition paint evenly, and the present invention further facilitates the development of ultra-high temperature paints and coatings by providing a new inorganic binder.

Claims (5)

60 to 85 parts by weight of the paint base; 131 to 141 parts by weight of methyl trimethoxysilane (MTMS), 100 to 118 parts by weight of isopropyl alcohol (IPA), 17 to 36 parts by weight of water, 0.25 to 0.29 parts by weight of hydrochloric acid (HCl 13.6%) by sol-gel method 20 to 25 parts by weight of an alkoxide inorganic binder brush obtained by condensation; Low friction ultra heat-resistant elastic paint prepared by containing 2 to 8 parts by weight of the crosslinking agent triphenylmethane 4,4,4-triisocyanate. The alkoxide inorganic binder is 136 parts by weight of methyl trimethoxysilane; 100 parts by weight of isopropyl alcohol; 35.17 parts water; A low friction super heat-resistant elastic coating composed of 0.27 parts by weight of hydrochloric acid (13.6%). The alkoxide inorganic binder is 136 parts by weight of methyl trimethoxysilane; 108.7 parts by weight of isopropyl alcohol; 26.77 parts water; A low friction super heat-resistant elastic coating composed of 0.27 parts by weight of hydrochloric acid (13.6%). The alkoxide inorganic binder is 136 parts by weight of methyl trimethoxysilane; 117.96 parts by weight of isopropyl alcohol; 17.77 parts water; A low friction super heat-resistant elastic coating composed of 0.27 parts by weight of hydrochloric acid (13.6%). The method of claim 1, Paint base is 50 to 60 parts by weight of fluororubber (FKM); 20 to 30 parts by weight of carbon black (HAF); 0.1 to 1 part by weight of stearic acid; 2 to 4 parts by weight of triallyl isocyanurate; 10-15 parts by weight of barium sulfate; 0.2-1 part by weight of vinyl-tris (β-methoxy-epoxy) silane; 2-4 parts by weight of dicumyl peroxide (40%) were kneaded in a roll or a mixer to obtain a mixture of base 1; 40 parts by weight of the mixture of Base 1 was dissolved in 60 parts by weight of methyl isobutyl ketone to obtain a mixture of Base 2, which was first painted; 60 to 70 parts by weight of the mixture of the base 2; 10-15 parts by weight of bisallynadic imide; 5-10 parts by weight of blocked isocyanate; Modified polyurethane (EFKA-4015 Aekyung Chemical Co., Ltd.) 0.5-1 part by weight; Modified polyurethane (manufactured by EFKA-65 Aekyung Chemical Co., Ltd.) 0.5 to 1 part by weight; 5 to 10 parts by weight of modified isoprene rubber; Low friction super heat-resistant elastic coating, characterized by obtained by mixing 4-10 parts by weight of methyl isobutyl ketone by mixing.