CS254247B1 - Windable electroinsulating laminated material - Google Patents

Abstract

The subject of the solution is an electroinsulating material type material, suitable especially for winding of rotating electrical machines. The essence of the solution is that overall 15 to 50 wt. composite insulator forming a binder. the bitumen component is a dian epoxide of structure I where 0 < n < 6, or a mixture of this dian epoxide in proportion 10: 90 to 90: 10 with another epoxide aromatic, preferred novolak type ·, and a crosslinking component whose proportion in the binder is 1 to 10% by weight, forming an ionic system catalyst based on blocked Lewis acid and organometallic esterification catalyst relative to each other 50: 1 to 1: 10.

Description

An invention of a winding electroinsulating laminate material of the silicone type suitable for winding electric machines rotating with a continuous operating temperature up to 155 ° C. The purpose of the solution is to obtain a suitable electroinsulating material of long-term and high temperature resistance, shape stability during curing in a short time, which can be produced in a shortened processing cycle.

In order to insulate the windings of traction and high-voltage electric machines, foil or tape insulating materials are applied based on sTa, from which the lamination and subsequent, usually heat, pressure-producing process is used to make compact insulation. The composition of insulators is determined by given conditions of functional operation of electric machines, expressing the multiplication of force fields. In the composition of servant insulators, the organic binder is the limiting element in terms of long-term temperature resistance.

For temperature-intensive applications of electrical insulating materials at continuous operating temperatures up to 155 ° C, epoxy compositions have a dominant position, which acquire the functional capability of the binder in the crosslinked insulation resulting from the interaction of the basic elements of the epoxy compositions - epoxy resin and hardener. Latency, crosslinking without the formation of low molecular weight products, and high physical characteristics of crosslinked insulation are principally requirements affecting the formulation of the epoxy composition.

The prior art solutions of the composition of the epoxy compositions set forth the requirements for these compositions over time, but none of the existing solutions have achieved a comprehensive solution to the problems. Resins crosslinked by ionic polymerization catalysts constitute the most prominent group of a series of epoxy compositions suitable as binders for mucous insulators. However, when using resins of one structural type, the compositions containing phenylglycidyl ethers are characterized by a lower latency of the compositions, and in the case of diane epoxy resins, a lower reactivity means an undesirable processing cycle delay.

When applying binders based on a mixture of different types of resins, e.g. a combination of cycloaliphatic and diane epoxides, the drawbacks are that insulators with lower temperature resistance result from the incorporation of non-aromatic components. In a combination of novolak-diane epoxides, ionic polymerization catalysts prefer crosslinking through the formation of an etheric glycidyl oxygen bond, resulting in the secondary hydroxyl groups of the diane component being largely unbound in the consolidated binder. . This effect is all the more significant the higher the epoxy content and the higher the hydroxyl group content.

The above mentioned drawbacks of the prior art are overcome by the wound electromagnetic insulating layer material of the silicone type according to the invention, which consists in that 15 to 50 wt. The bonded insulator forms a binder, the resin component of which is a diane epoxide structure

CH-CH-CH 2 O o

C H '· C H *

Z i

OH

S ^w

wherein <n <6 or a mixture of palm epoxide in a ratio of 10: 90 to 90: 10 with another aromatic, preferred novolak epoxide, wherein the number of aromatic cycles in the molecule is 2 to 5 and a crosslinking component having 1 to 10% % by weight, forms a blocked catalyst system based on blocked Lewls acids and an organometallic esterification catalyst in a ratio of 50: 1 to 1:10 relative to each other.

In the proposed solution of electroinsulating material for. compact base binder · characterized by:

- latent character of crosslinking, allowing long-term, up to eight months shelf life of mica prepregs at ambient temperature, - high conversion of functional epoxy and hydroxyl groups at elevated temperatures - above 120 ° C, - low polar structure, - high and durable temperature resistance up to 155 ° C , flexibility and toughness of the crosslinked composition.

The fused electro-insulating material prepared by application of the above mentioned binder has the following improved properties compared to the known insulators so far:

- higher temperature-oxidation stability at operating temperatures up to 155 ° C, - dielectric losses of 0.01 to 0.10 in the temperature range of 105 ° C to 155 ° C, - shape stability at curing after 15 to 30 minutes.

The invention is further specified in several examples:

Example 1

A mixture of epoxydian resin having an epoxy equivalent of 920 and a softening point of 87 ° C and an epoxy novolak resin having an epoxy equivalent of 180 and a viscosity of 1.6 Pa. s at 50 ° C in a ratio of 40: 60 wt. 0.5 parts by weight are modified. % BFs-monoethylamine and 5 wt. parts of a cresyl titanate polymer containing

14.5 to 16.5% TiO2. All components are dissolved in a 50:50 mixture of methyl ethyl ketone and toluene and wet laminated from a binder solution, 70 g / m ² plain paper, and a 0.05 mm thick delubricated glass fabric to provide a layered insulator from which 80 to 100 ° C removes the solvent. The binder deposit amounts to 30 to 40% by weight of the insulator. Thermal treatment at 130 to 200 ° C for machine winding results in low dielectric loss insulation.

Example 2

Made of 120 g / m ² plain paper, 0.05 mm glass fabric, 32 g / m ² biaxially oriented polyethylene terephthalate film and an acetone binder solution consisting of 20 parts by weight of epoxydian resin with an epoxy equivalent of 490 and a 62 ° C dipping point, 80 wt. parts of an epoxy novolac resin having an epoxy equivalent of 185 and a viscosity of 60 Pa. s at 50 ° C, 3 wt. parts by weight of BF 3 -benzylamine, 0.5 wt. A portion of a butyl titanate polymer having a molecular weight of about 1200 and a content of 33-35% T102 is prepared by combining a dry and wet laminating process to form a multilayer insulator in which the binder portion constitutes 20-35% by weight of the insulator. The multilayer foil insulator thus prepared is suitable, in particular, for the isolation of traction windings of electrical machines by pressing processes.

The solution according to the invention is applicable, in particular, directly in the sector of manufacture of electrical insulating materials, whereby the technical and economic effects are also manifested in the application of the electrical insulating material in rotating electrical machines.

Claims (1)

Retractable electroinsulating laminate of the downstream type with a carrier and an epoxy binder, suitable in particular for temperature class F, characterized in that up to a total of 15% by weight of up to 50 wt. The composite insulator forms a binder, the bitumen component of which is a diane epoxide structure C--CMo CH-0 z ^CH 2 ° A C) where 0 <n <6, optionally a 10: 90 to 90: 10 mixture of this diane epoxide with another aromatic, preferably novolak epoxide, wherein the number of aromatic cycles in the molecule is 2 to 5 and the crosslinker component of which 1 % to 10 wt.%, the blocked Lewis acid ion catalyst system and the organometallic esterification catalyst system are in a ratio of 50: 1 to 1:10 relative to each other.