KR20100096491A - Siloxane modified polyamideimide resin and producing method of the same - Google Patents

Abstract

PURPOSE: A siloxane modified polyamideimide resin and a manufacturing method thereof are provided to manufacture a coating agent capable of uniformly forming an insulation paint coated film on an edge unit of a straight angle conductor. CONSTITUTION: A manufacturing method of a siloxane modified polyamideimide resin comprises: a step of condense-reacting a polyamideimide resin marked with chemical formula 2 and polydimethylsiloxane dicarboxylic acid marked with chemical formula 3. In the chemical formulas, N is a natural number selected from 1~20. The molecular weight of the siloxane modified polyamideimide resin is 10,000~100,000.

Description

Siloxane-modified polyamideimide resin and its manufacturing method {SILOXANE MODIFIED POLYAMIDEIMIDE RESIN AND PRODUCING METHOD OF THE SAME}

The present invention relates to a siloxane-modified polyamideimide resin that can be used for the production of an insulating layer of a flat winding, and a method of manufacturing the same. More particularly, the film of the edge portion of the flat winding is uniformly formed, and has excellent electrical insulation, flexibility, and wear resistance. The present invention relates to a siloxane-modified polyamideimide resin prepared by condensation reaction with polydimethylsiloxane dicarboxylic acid in order to secure such a material, and a method for producing the same.

In the conventional flat winding, the circular wire whose cross section is circular is rolled, and the cross section has a rectangular shape. Specifically, there is a method of manufacturing a flat wire first by rolling a round wire, and then applying and curing an insulating paint according to a predetermined rule. There is a way. The insulating paint is coated with a polyurethane insulating paint, a polyester insulating paint, and a polyesterimide insulating paint on the outer circumference of an inner conductor such as copper, copper alloy, and aluminum, which are conductors.

According to the method of rolling the round wire first to make a flat wire, and then applying and curing the insulating paint, the edge coating of the flat conductor is too thin, or the edge coating is too thin even if the insulating paint is partially formed. There is a disadvantage that it is difficult to form a uniform film as a whole.

As such, when the film of the edge portion of the flat winding is formed too thin, the surface of the conductor may be easily exposed due to the damage of the film. In this case, the electrical insulation is sharply degraded in the thin film or the exposed portion of the conductor. Problems may occur in the use of, and the reliability of the flat winding is lowered, there is an undesirable problem.

In response to this problem, a method of forming a thick film may be considered in order to maintain electrical insulation during the processing of the flat winding, but this is pointed out that the use of the varnish is increased compared to the round wire, resulting in a decrease in economic efficiency in the manufacture of the flat winding. have. In addition, in this case, a disadvantage arises in that the coating is not evenly applied.

As described above, in the method of manufacturing a flat conductor after applying a rolling wire and applying and curing an insulating coating on the outside thereof according to a predetermined rule, the electrical insulation, flexibility, and abrasion resistance are deteriorated, Various efforts have been made in the related art to solve the problem that the insulating coating film is not uniformly formed, and the present invention has been made under such a technical background.

The problem to be solved by the present invention is to provide a more improved flexibility for the efficient processing of electrical equipment such as a motor or alternator while maintaining the heat resistance of the polyamideimide resin in manufacturing a flat winding, In order to maintain insulation, the overall thick film is uniformly formed on the edge and the flat portion to minimize the economic loss, and the insulating coating film of the flat winding is uniformly formed. It is an object of the present invention to provide a polyamideimide resin composition and a method for producing the same.

The siloxane-modified polyamideimide resin provided as a means for solving the problems of the present invention is composed of a monomer having the structure of the following general formula (1), and is used for producing a covering material for a flat winding.

In the formula (1), m is a subscript, m is a natural number of 1 to 50, n is a natural number of 1 to 20.

A method for producing a siloxane-modified polyamideimide resin provided as a means for solving the problems of the present invention is characterized by being produced by condensation reaction between a polyamideimide resin and a polydimethylsiloxane dicarboxylic acid.

According to the present invention, it is possible to manufacture a coating material of a flat winding, in which the flexibility and wear resistance are further improved while maintaining the heat resistance and electrical insulation property of the polyamideimide resin, and the insulating coating film formed on the edge portion of the flat conductor is uniformly formed. have. It is preferable to use the coating | covering material provided by this invention especially for manufacturing the coating layer of two or more layers of an insulated wire.

Hereinafter, the present invention will be described in detail with reference to examples, and detailed description will be made with reference to the accompanying drawings in order to help understanding of the present invention. However, embodiments according to the present invention can be modified in many different forms, and the scope of the present invention should not be construed as being limited to the embodiments described below. Embodiments of the present invention are provided to more fully describe the present invention to those skilled in the art.

The siloxane-modified polyamideimide resin according to the present invention is preferably composed of a monomer having the structure of Chemical Formula 1, and used for the production of an insulating coating material for a flat winding.

The numerical ranges for the subscripts m and n shown in the formula (1) may be selected to a value adjusted so that the molecular weight of the siloxane-modified polyamideimide resin can be 10,000 to 100,000. Regarding the numerical range of the molecular weight of the siloxane-modified polyamideimide resin, if it falls below the lower limit, it is not preferable for the flat winding characteristics such as the coating is not sufficiently formed during the coating process of the insulating coating, and the coating is broken, and the upper limit is exceeded. The lower viscosity of the varnish may result in a drastic increase in productivity during the coating process, and in more severe cases, it may not be applicable to the coating process. In particular, in the above formula (1), in relation to the numerical range relating to the subscript n, the lower limit thereof becomes the same structure as the general polyamideimide resin, and thus the flexibility is lost, and when the upper limit is exceeded, the polyamideimide resin It is unpreferable because the heat resistance which the has cannot be ensured.

When the method for producing a siloxane-modified polyamideimide resin according to the present invention is prepared by condensation reaction between a polyamideimide resin comprising a monomer having a structure of Formula 2 and a polydimethylsiloxane dicarboxylic acid having a structure of Formula 3 below: desirable.

<Formula 2>

N represented by a subscript in Formula 2 is a natural number of 1 to 20.

<Formula 3>

M represented by a subscript in Formula 3 is a natural number of 1 to 50.

In addition to the solvent, the siloxane-modified polyamideimide resin according to the present invention may further include suitable additive components according to the use purpose, and examples of such additive components include radical polymerization initiators, copper antioxidants, thickeners, surfactants, and the like. These additives may be optionally included in an amount of 0.5 to 10 parts by weight based on 100 parts by weight of the siloxane-modified polyamideimide resin based on solids.

Resin solutions were prepared as shown in Comparative Examples (1, 2) and Examples (1-5), which are set as follows.

Comparative Example 1

Into a reactor equipped with a stirrer, a cooler, and a thermometer, 1,160 g of N-methyl pyrrolidone, 290 g of styrene, 345.3 g of trimellitic hydride (TMA) and 425 g of 4,4-dimethyl diisocyanate (DMI) were added to a nitrogen atmosphere. The reaction was carried out at 90 ° C. for 5 hours. Subsequently, the temperature was raised to 140 ° C. over 2 hours under a nitrogen atmosphere, and the reaction was continued for 5 hours. Thereafter, the resultant was cooled and diluted so that the weight ratio of N-methylpyrrolidone / xylene was 1/4, thereby obtaining a resin solution (A) having a nonvolatile content of 25% by weight.

Comparative Example 2

Prepared in the same manner as in Comparative Example 1, but finally obtained a resin solution (B) having a nonvolatile content of 15% by weight.

Example 1

As a solvent, 290 g of xylene, 1,160 g of N-methylpyrrolidone, 345,3 g of trimellitic hydride (TMA) and 425 g of 4,4-dimethyl diisocyanate (MDI) were added thereto, and a polydimethylsiloxane dicarboxylic acid was added. 13% by weight (based on the TMA weight) was added and reacted at 90 ° C. for 5 hours under a nitrogen atmosphere. Then, the temperature was raised to 140 ° C. over 2 hours under a nitrogen atmosphere, and the reaction was continued for 5 hours. Thereafter, the resultant was cooled and diluted so that the weight ratio of N-methylpyrrolidone / xylene became 1/4, thereby obtaining a resin solution (C) having a nonvolatile content of 25% by weight.

Example 2

Except that 30% by weight of the polydimethylsiloxane dicarboxylic acid (based on the TMA weight) was prepared in the same manner as in Example 1 to obtain a resin solution (D).

Example 3

Except that the polydimethylsiloxane dicarboxylic acid 50% by weight (based on the TMA weight) was prepared in the same manner as in Example 1 to obtain a resin solution (E).

Example 4

Except for using the polydimethylsiloxane dicarboxylic acid 6% by weight (based on the TMA weight) was prepared in the same manner as in Example 1 to obtain a resin solution (F).

Example 5

Except for using the polydimethylsiloxane dicarboxylic acid 1% by weight (based on the TMA weight) was prepared in the same manner as in Example 1 to obtain a resin solution (G).

The viscosity, solid content, and flexibility of the resin solutions (A to G) prepared according to Comparative Examples (1, 2) and Examples (1 to 5) described above are shown in Table 1 below.

Viscosity was measured using a Brookfield viscometer, and the solid content was cured for 2 hours in a 200 ° C. hot air circulating oven, and the weight was expressed as a percentage after the solvent was volatilized to the weight before volatilization. The surface tension of the resin solutions was measured using a ring tension surface tension meter.

On the other hand, by coating the insulating coating material having a thickness of 0.030mm using resin solutions A to G prepared as described above to cover the flat conductor having a thickness of 1.064 mm and a width of 0.946 mm, and then cured. After fabricating the insulation coating of the flat winding, the cross-section of the flat winding was polished well to visually observe the appearance of the film in order to determine the film tendency of the edge portion, and the edge coverage was measured. Edge coverage was measured up, down, left, and right of the flat portion of the cross section of the flat winding, and after measuring the four edge portions, respectively, edge coverage was calculated according to the following equation.

Breakdown Voltage (BDV) was measured according to IEC 60317. The measurement method of BVD is determined by winding. However, for the triangular windings with small cross-sectional area, a separate standard is not established. It is evaluated as preferable.

division
Example (1-5) Comparative Example (1, 2) One 2 3 4 5 One 2 Resin Solution Viscosity 15 18 28 16 14 14 11 Solid content (%) 28 32 38 27.1 27.3 25 15 Surface tension (dyne / cm) 24 23 23 26 28 34 33 film Exterior Good Good Good Good Good Good Good BDV (V) 9200 9600 8200 9200 8200 5400 6200 Edge coverage (%) 94 98 86 95 79 65 42

After manufacturing the flat conductor by rolling the round wire, and manufacturing the flat winding by the method of coating and curing the insulating paint on the outside thereof, even if the coating is cured, the coating of the edge part is formed uniformly and the electrical insulation or flexibility For this to be excellent, it is preferable that the viscosity of the insulating paint is 5 to 40 poise, the solid content is 10 to 40%, and the surface tension is 24 to 32 dyne / cm.

With respect to the numerical range for the viscosity of the insulating paint, if the lower limit is not desirable, the desired coating is not formed, and if the upper limit is exceeded, the coating operation does not proceed smoothly and is not preferable. Regarding the numerical range of the surface tension of the insulating paint, if it falls below the lower limit, the varnish flow is too severe and the film is formed too thin at the edge portion, and if the upper limit is exceeded, the flat portion is thicker than the thickness of the edge coating. The film is formed too thick, resulting in poor edge coverage. If the edge coverage is poor in the coating of the insulating paint, the film thickness is generated, the electrical characteristics are deteriorated, which is undesirable.

As shown in Table 1, it can be confirmed that in Examples 1 to 5, excellent evaluation results were measured in comparison with Comparative Examples (1.2) in all physical properties such as BVD and edge coverage.

Optimal embodiments of the present invention described above have been disclosed. Although specific terms have been used herein, they are used only for the purpose of describing the present invention in detail to those skilled in the art and are not intended to limit the scope of the present invention as defined in the claims or the claims.

Claims (3)

A siloxane-modified polyamideimide resin, comprising a monomer having a structure of Formula 1, used for preparing an insulating coating of a flat winding. <Formula 1>

In the formula (1), m is a subscript, m is a natural number of 1 to 50, n is a natural number of 1 to 20. The method of claim 1, The said siloxane-modified polyamideimide resin has the molecular weight 10,000-100,000, The siloxane-modified polyamideimide resin characterized by the above-mentioned. The siloxane-modified polyamideimide resin according to claim 1 or 2 is condensation reaction of a polyamideimide resin comprising a monomer having a structure of formula (2) with a polydimethylsiloxane dicarboxylic acid having a structure of formula (3). A method for producing a siloxane-modified polyamideimide resin, which is prepared. <Formula 2>

N represented by a subscript in Formula 2 is a natural number of 1 to 20. <Formula 3>

M represented by a subscript in Formula 3 is a natural number of 1 to 50.