FR2482116A1 - POLYETHER-IMIDE RESIN, COATING COMPOSITION CONTAINING THE RESIN, AND ISOLATED ELECTRIC CONDUCTORS USING THE SAME - Google Patents

Abstract

POLYETHER-IMIDE RESIN, COATING COMPOSITION CONTAINING THE SAID RESIN AND ELECTRIC CONDUCTORS BEARING AN INSULATING COATING OF THE SAID RESIN. THE RESIN IS A POLYETHER-IMIDE RESIN OBTAINED BY POLYCONDENSATION OF A DIANHYDRIDE OF FORMULA: (CF DRAWING IN BOPI) OR OF A MIXTURE OF THIS WITH AT LEAST ONE OTHER DIANHYDRIDE WITH 0.99 TO 1.01MOLES, BY MOLE OF DIANHYDRIDE, OF A DIISOCYANATE AT A TEMPERATURE OF APPROXIMATELY 60 TO 200C IN THE PRESENCE OF AN INERT SOLVENT. APPLICATION AS INSULATING COATINGS ON ELECTRIC CONDUCTORS.

Description

The present invention relates to a polyresin resin

  ether-imide, to a coating composition containing this

  resin in solution in an organic solvent and with

  electrical conductors insulated with polyether resin

imide.

  It is known that polyether-imides can be used

  reaction products of a dianhydride of a diphenolic compound and a diamine, for example methylene- dianiline, to apply resinous coatings on electrical conductors. For example, United States Patent No. 3,847,867 may be consulted. It is also known that polyamidesimides consisting of reaction products of a carboxylic acid anhydride, a diamine and a diisocyanate can be used to form coatings on electrical conductors. For example, U.S. Patent No. 3,817,926 is known. It is also known that polyimide amide resins consisting of reaction products of tribasic acid anhydride and diisocyanate can be used to form insulating coatings: cf.

  for example, U.S. Patent No. 3,541,038.

  It has now been found according to the invention that reaction products consisting of polyether-imide resins and of exceptional interest can be formed by reacting a dianhydride of a diphenolic compound or a mixture thereof with at least one other dianhydride and a diisocyanate. These products are preferred to known products for the application of insulating coating on conductors

  such as magnetic wire and magnetic tape.

  because they are safer, better and more economically

  c. The resins are preferably applied in the state of

  compositions obtained by dilution in an organic solvent.

  The invention therefore relates firstly to high molecular weight polyether-imide resins prepared by subjecting a dianhydride of formula:

\. C H3 \

o

O CH3 O

  or a mixture thereof with at least one other acid-tricarboxylic acid dianhydride, and 0.99 to 1.01 moles, per mole of dianhydride, of an organic diisocyanate of the formula:

O = C = N -R - N = C = O

  in which R represents * -C -CH 2 ou or at a polycondensation at a temperature of about 60 to 200 ° C

in the presence of an inert solvent.

  The invention also includes coating compositions

  consist of a polyether-imide resin such as

  defined above in solution in an organic solvent.

  The invention also comprises, as industrial articles

  new triels, electrical conductors carrying an insulating coating comprising a polyether-imide resin

as defined above.

  In a preferred embodiment of the invention, the resin is prepared in the presence of a catalytic amount

  preferably from traces to about 10 mole% (as

  dianhydride) of 2-methylimidazole. Preferably

  also, the organic diisocyanate is diphenylmethane

  diisocyanate. The dianhydride, which is the bis [3,4-dicarboxy-phenoxy] -4-phenyl] propane dianhydride, also known as the bisphenol-A dianhydride, is described in US Pat. No. 3,847. 867 above and may be prepared by hydrolysis, followed by dehydration, of the reaction product of a nitrosubstituted phenyldinitrile with a metal salt.

  of a diphenol in the presence of a dipolar aprotic solvent.

  The advantageous properties of the polymers of the invention can be varied by replacing up to 50 mole percent of bisphenol-A dianhydride with one or more tetracarboxylic acid dianhydrides, which can be either aromatic dianhydrides or aliphatic dianhydrides, such as indicated below: The aromatic dianhydrides useful in the invention have the formula

O

ul II O R O

II I!

O O

  wherein R is a tetravalent radical containing at least one ring of 6 carbon atoms and having benzenoid unsaturation, each pair of carboxyl groups being bonded to a different, adjacent carbon atom. Among these dianhydrides there may be mentioned, for example pyromellitic dianhydride,

  the dianhydride of naphthalene tetracarboxylic acid

lic-2,3,6,7,

  the dianhydride of benzophenone tetracarboxylic acid

that -3,3 ', 4,4',

  the dianhydride of benzene tetracarboxylic acid

  1,2,3,4-dianhydride of bis (3,4-dicarboxyphenyl) sulfone, dianhydride of bis (2,2-dicarboxyphenyl) methane, dianhydride of 2,6-dichloroacid naphthalene 1,4,5,8-tetracarboxylic acid, dichloro-2,7-naphthalene tetracarboxylic acid-1,4,5,8-dianhydride 2,3,6,7-tetrachloro-naphthalene tetracarboxylic acid dianhydride !, 4,5,8,

  the dianhydride of naphthalene tetracarboxylic acid

lic-1,4,5,8,

  the dianhydride of naphthalene tetracarboxylic acid

what 1,2,4,5,

  the dianhydride of diphenyl tetracarboxylic acid

  3,3 ', 4,4'-dianhydride of naphthalene tetracarboxylic acid-1, 2,5,6,

  the dianhydride of diphenyl tetracarboxylic acid

  2,2'-2,2'-dianhydride of bis (3,4-dicarboxyphenyl) -2,2 propane,

  the dianhydride of phenylene tetracarboxylic acid

  3,4,9,10, bis (3,4-dicarboxyphenyl) ether dianhydride, 2,3-bis (2,3-dicarboxyphenyl) propane dianhydride, bis (dicarboxy-2) dianhydride , 3-phenyl) -1,1 ethane, the dianhydride of bis (3,4-dicarboxyphenyl) -1,1 ethane,

and the like.

  The aliphatic dianhydrides that can be used in the present invention are those having the formula:

C C

O R 0

C

O O

  R 'is a tetravalent radical with straight chain or alicyclic

  than having from 1 to 10 carbon atoms. Among these dianhydrides

  mention may be made of: the dianhydride of methane tetracarboxylic acid, the dianhydride of ethane tetracarboxylic acid, the dianhydride of propane tetracarboxylic acid, the dianhydride of butane tetracarboxylic acid and the dianhydride of hexane tetracarboxylic acid, the dianhydride of cyclohexane tetracarboxylic acid,

and the like.

  Organic diisocyanates can be prepared by methods known to those skilled in the art and can be found

also in the trade.

  The polymer is prepared by reacting the dianhydride of Bisphenol-A (BPADA) and diphenylmethane diisocyanate (MDI) or phenoxyphenyldiisocyanate in the presence or absence of 2-methylimidazole (2-MeIM) as a catalyst in a solvent organic such as N-methylpyrrolidone (NMP), dimethylacetamide (DMAC), an aromatic hydrocarbon containing for example from 6 to 40 carbon atoms, among others xylene, or a commercial aromatic hydrocarbon solvent, for example the product brand Solvesso 100 , or in a mixture of such

  solvents, for example NMP-DMAC, NMP-xylene, NMP-

  DMAC-xylene- or -Solvesso 100, etc. The recommended reaction mode is as follows

0 0

D C H + N (1 + X%) O = C = N-R-N = C = O

  In the above scheme, R represents: 2MeM CH CHH

N CH 2

C - - C

  CHn in the diagram above, R represents

/ \ CH2- /

-O or

or a mixture of such radicals.

  The optimum molar proportions between the MDI (or oxygenated analogue compound) and BPA-DA are from 0.99 to 1.01: 1.00 and the proportion of catalyst is from 0 to 10 mol% relative to the dianhydride. If it is desired to obtain a coating composition, the resin can be prepared in the organic solvent, for example NMP, NMP-DMAC, DMP-xylene or Solvesso 100, etc., or the resin can be isolated and redissolved in such a solvent or in methylene chloride, dimethylformamide, cresylic acid,

phenol or a similar solvent.

  We appeal. to procedures of preparation

  classics. For example, the United States Patent

  United States No. 3,541,038, which gives indications on reaction times, temperatures, etc. In a particular embodiment, BPA-DA is reacted with MDI in the presence of 2-MeiM and a 2.3: 1 mixture of N-methylpyrrolidone and xylene at a temperature of

  about 1350C for about 24 hours. During the first

  During the first reaction period, there is a continuous release of carbon dioxide. Subsequently, the viscosity of the solution increases

  little by little and the release of carbon dioxide ceases practically

  cally. It can be terminated advantageously when one reaches a viscosity Zi to Z2 1/2 on the Gardner scale. Such enamel can be used as a single layer on a conductive wire or as an outer layer on a polyester or polyester-imide underlayer. According to common practice, other additives such as minor proportions of aliphatic amino compounds,

  known phenolic resins, titanium esters, poly-

  isocyanates and similar additives without this

  enumeration can be considered as limiting the invention.

  The remainder of the description refers to the attached figure

  which represents in section a magnetic wire according to the invention.

  With reference to this figure, the magnetic wire 10 consists of a conductor 11 covered with a layer 12 of a resinous polyether-imide dianhydride Bisphenol A and a diisocyanate. Although a driver was shown

  it has a circular section, it is obvious that we can also use

  square or rectangular conductors, in the form of ribbons or flat sheets, without departing from the scope of the invention. The layer 12 may consist of a polyether-imide prepared as described in the following example which illustrates the invention without however limiting its scope, in this example, the indications of parts and% are by weight unless mentioned

opposite.

Example 1

  In a 5 liter 3-neck flask equipped with an agitator,

  a thermometer, a condenser and an introducer tube.

  of nitrogen, 1 mole (520 g) of bis [(3,4-dicarboxy)

  phenoxy) -4-phenyl] -2.2 propane, 1.01 mole (252.5 g) of diphenyl-

  methane diisocyanate, 0.05 mole (4.1 g) of 2-methylimidazole, 838.94 g of N-methylpyrrolidone and 364.74 g of xylene. The mixture is brought to room temperature at 135 ° C in about 2 hours and maintained at that temperature for 18 to 22 hours until the Zl-Z2 1/2 viscosity is reached. During the reaction, the color of the solution changes from yellow to orange then to bright red and finally bright red red during the first two hours of heating, and there is continuous release of carbon dioxide. Subsequently, the viscosity of the solution gradually increases and the release of

CO2 continues but weakly.

  The composition contains the polyether-imide resin at 39% solids content in the organic solvent and can be used as a coating composition for electrical conductors. If desired, the resin can be isolated by pouring the cooled reaction mixture into the

  methanol, which causes the precipitation of the polymer.

  Although the operation has been described with reference to diphenylmethane diisocyanate, this component can be replaced

  in whole or in part by phenoxyphenyl diisocyanate.

  In addition, the catalyst can be removed.

  The composition of this example was applied to 1.024 mm single coated copper wire in an industrial wire tower. A thickness of 79 to 84 microns was achieved in 7 passes. The coated yarn has the following properties: Speed, m / min 12 13.5 15 Flexibility 25 + lX lX rupture Thermal shock - 20% - 30 '- 260 C 1X lX rupture 20% Isolation loss temperature C at 2,000 g . 361 358 330 At the first two coating speeds, a conductor of excellent quality is obtained with a regular insulating coating. The composition of this example was applied to 1.024 mm copper wire in an outer layer on an ethylene glycol terephthalate / glycerol polyester underlayer (a product of the invention).

  Alkanex 9516 trading company General Electric). The thick-

  The final range was 74 to 78 microns. The coated wire has the following properties: Speed, m / min 17.5 15 13.5 12 10.5 Flexibility 25 + break 3X 2X lX lX 2X Thermal shock -20% -301 -260 C break 4X: 4X 4X 4X 3X Isolation loss temperature C at 2,000 g. 256 248 249 223 196 At the lowest coating speeds, an excellent conductor with a smooth coating of

double insulation.

  The composition of this example was applied to 1.024 mm copper wire in an outer layer on an undercoat of a polyester of ethylene glycol terephthalate / tris (2-hydroxyethyl) isocyanurate (commercial product Isonel 678). from Schenectady Chemical). We got a final thickness

  from 74 to 78 microns. The coated yarn has the following properties:

  speed: m / min 13.5 12 Flexibility 25 + lX 1X Thermal shock -20% 30 '-260 C rupture 3X rupture 3X Insulation loss temperature C at 2.000 g 331 352 With the exception of poor thermal shock resistance,

  we arrived at a driver wearing a good coating.

  It is clear that the invention is in no way limited to the preferred embodiments described above as examples and that one skilled in the art can make modifications without

to get out of his frame.

Example 2

  The general procedure of Example 1 was repeated except that 10 mol% of bisphenol-A was replaced by benzophenonetetracarboxylic acid dianhydride (BTDA). 936 g (1.8 moles) bisphenol-A dianhydride 64.45g (0.2 mole) BTDA, 505 g (2.02 moles) diphenylmethane diisocyanate, 1278 g N-methylpyrrolidone (NMP) were used. ), 556 g of Solvesso 100 and 16.4 g (0.2 mole) of 2-methylimidazole. At a Gardner viscosity of about Z5.25, the mixture was cooled to room temperature and cut with a solvent mixture, 400 g of NMP and 174 g of

  Solvesso 100, then again reacted and heated up

  only at a final Gardner viscosity of Z1. The solids content

  of this composition was 39.66%.

  The composition of Example 2 was applied as a single coat to a 1.024 mm copper wire, 0.076 to 0.081 mm thick, by means of a commercial wire tower. The following properties were observed: Speed, m / min 12 13.5 17.5 Flexibility 25 + 1X lX 1X Thermal shock 1X 2X lX Isolation loss temperature C (2000 g) 362 346 321 Example 2 as a topcoat on an Isonel 678 basis. A final thickness of 0.073 to 0.078 mm was obtained. The following properties were observed: Speed (m / min) 10.5 12 13, 5 Flexibility 25 + lX 1X rupture for 3 X Isolation loss temperature

 C 408 406 361

  Half of the composition of Example 2 was again cut with 236.3 g of NMP and 103.7 g of Solvesso 100, brought to 135 ° C. and reacted until a viscosity was obtained.

  Gardner from Z1. The solids content was 33.11%.

  This enamel was used as a single coating on 1.024 mm copper wire, applied at a thickness of 0.073 to 0.081 mm in a commercial wire tower. The following properties were observed: Speed m / min 12 13.5 17.5 Flexibility 25 + 1 X 1X 2X Isolation loss temperature

 C 383 368 332

Thermal CaX lX 1X 1X

  The above composition was applied as a coating

  higher on a base of Isonel 678, coated to a thickness

  final 0.073 to 0.078 mm. The following properties have been observed:

  vantes: Speed (m / min) 10.5 12 13.5 Flexibility 25 + 2X lX 3X rupture Insulation loss temperature

 C 408 392 371

Example 3

  The general procedure of Example 2 was repeated except that 43.6 g (0.2 mol) of pyromellitic dianhydride was used.

  instead of the dianhydride of benzophenonetetracarboxylic acid

  Example 2. All other quantities were the same.

  After a first cut with skimmers and further reaction

  As in Example 2, a composition having a Gardner viscosity of Z1 and a solids content of 38.26% was obtained. The following properties were observed when the composition was used as a single coating and coating

higher on Isonel 678.

UNIQUE COATING

  Thread Thickness mm Speed m / min Flexibility 25 Temperature OC Thermal shock

COATING

Copper 1,024 m

0.071 - 0.078

13.5 17.5 18

iX lX iX isolation loss 1X 2X 2X

SUPERIOR

  Wire Thickness (mm) Speed m / min Flexibility 25 + Pt Temperature, 5 lx Copper 1,024 mm

0.073 - 0.081

12 13

lx lx Isolation alert

QC 393 358 379

  Thermal shock rupture 3X 3X to 3X Reaction was again half of the composition of Example 3 as in Example 2 after a second cut with solvents, 236.3 g of NMP and 103.7 g of Solvesso 100, until a Gardner viscosity of Z2 is obtained. The solids content was 31.64%. The following properties have been observed for a single coating and a top coating on

the Isonel 678.

UNIQUE COATING

  Thread Thickness (mm) Speed (m / min) Flexibility 25 + Insulation loss temperature OC Thermal shock

SUPERIOR COVER

  Thread Thickness (mm) Speed Flexibility 25 + Insulation loss temperature C Thermal shock Copper 1,024 mm

0.071 - 0.081

13.5 17.5 18

lx lx lx 3x lx lx copper 1.024 mm

0.071 - 0.076

, 5 12 13.5

lX 1X lX

399,381,379

rupture rupture rupture

3 to 3X to 3X 3X

Claims (12)

  1. Polyether-imide resin of high molar mass, characterized in that it was prepared by subjecting a dianhydride of formula: - CH3 <X C - Y0 c / C ilI O CH3 È   or a mixture thereof with at least one other dianhydride of a tetracarboxylic acid and 0.99 to 1.01 moles, per mole of the dianhydride, of an organic diisocyanate of the formula: O = C = N - R - N = C = O   wherein R is CH 2 or polycondensation at a temperature of about 60 to 200 ° C in the presence of an inert solvent.   Polyether-imide resin according to Claim 1, characterized in that the polycondensation is carried out in   presence of a catalytic amount of 2-methylimidazole.   3. polyether-imide resin according to claim 2, characterized in that the amount of 2-methylimidazole is between traces and about 10 mol% relative to dianhydride.   4. Polyether-imide resin according to claim 1, characterized in that, in the organic diisocyanate, R represents H 2 Polyether-imide resin according to claim 1,   characterized in that the inert solvent is N-methyl-   pyrrolidone, dimethylacetamide, an aromatic hydrocarbon   or any mixture of these solvents.   6. Polyether-imide resin according to claim 1, characterized in that the other dianhydride is dianhydride   benzophenone tetracarboxylic acid.   7. Polyether-imide resin according to claim 1, characterized in that the other dianhydride is dianhydride pyromellitic.   8. Coating composition consisting of a resin of   polyether-imide in solution in an organic solvent,   characterized in that the polyetherimide resin is a resin according to claim 1.   9. A coating composition according to claim 8, characterized in that the organic solvent is selected from the group consisting of N-methylpyrrolidone, dimethylacetamide, an aromatic hydrocarbon or any mixture of these solvents. 10. Electrical conductor carrying an insulating resin coating characterized in thata resin is a resin according to claim 1.   11. Conductor according to claim 10, characterized in that this coating consists exclusively of a resin according to claim 1.   12. Conductor according to claim 10, characterized in that the coating consists of an underlayer of a polyester or polyesterimide and an outer layer of a resin according to claim 1.