Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
  • B29C53/00—Shaping by bending, folding, twisting, straightening or flattening; Apparatus therefor
  • B29C53/80—Component parts, details or accessories; Auxiliary operations
  • B29C53/84—Heating or cooling
  • B29C53/845—Heating or cooling especially adapted for winding and joining
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
  • C08J5/00—Manufacture of articles or shaped materials containing macromolecular substances
  • C08J5/24—Impregnating materials with prepolymers which can be polymerised in situ, e.g. manufacture of prepregs
  • C08J5/241—Impregnating materials with prepolymers which can be polymerised in situ, e.g. manufacture of prepregs using inorganic fibres
  • C08J5/242—Impregnating materials with prepolymers which can be polymerised in situ, e.g. manufacture of prepregs using inorganic fibres using metal fibres
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
  • B29C35/00—Heating, cooling or curing, e.g. crosslinking or vulcanising; Apparatus therefor
  • B29C35/02—Heating or curing, e.g. crosslinking or vulcanizing during moulding, e.g. in a mould
  • B29C35/0277—Apparatus with continuous transport of the material to be cured
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
  • C08J5/00—Manufacture of articles or shaped materials containing macromolecular substances
  • C08J5/24—Impregnating materials with prepolymers which can be polymerised in situ, e.g. manufacture of prepregs
  • C08J5/241—Impregnating materials with prepolymers which can be polymerised in situ, e.g. manufacture of prepregs using inorganic fibres
  • C08J5/244—Impregnating materials with prepolymers which can be polymerised in situ, e.g. manufacture of prepregs using inorganic fibres using glass fibres
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
  • C08J5/00—Manufacture of articles or shaped materials containing macromolecular substances
  • C08J5/24—Impregnating materials with prepolymers which can be polymerised in situ, e.g. manufacture of prepregs
  • C08J5/246—Impregnating materials with prepolymers which can be polymerised in situ, e.g. manufacture of prepregs using polymer based synthetic fibres
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
  • C08J5/00—Manufacture of articles or shaped materials containing macromolecular substances
  • C08J5/24—Impregnating materials with prepolymers which can be polymerised in situ, e.g. manufacture of prepregs
  • C08J5/247—Impregnating materials with prepolymers which can be polymerised in situ, e.g. manufacture of prepregs using fibres of at least two types
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
  • B29C35/00—Heating, cooling or curing, e.g. crosslinking or vulcanising; Apparatus therefor
  • B29C35/02—Heating or curing, e.g. crosslinking or vulcanizing during moulding, e.g. in a mould
  • B29C35/08—Heating or curing, e.g. crosslinking or vulcanizing during moulding, e.g. in a mould by wave energy or particle radiation
  • B29C35/0805—Heating or curing, e.g. crosslinking or vulcanizing during moulding, e.g. in a mould by wave energy or particle radiation using electromagnetic radiation
  • B29C2035/0827—Heating or curing, e.g. crosslinking or vulcanizing during moulding, e.g. in a mould by wave energy or particle radiation using electromagnetic radiation using UV radiation
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
  • B29C35/00—Heating, cooling or curing, e.g. crosslinking or vulcanising; Apparatus therefor
  • B29C35/02—Heating or curing, e.g. crosslinking or vulcanizing during moulding, e.g. in a mould
  • B29C35/08—Heating or curing, e.g. crosslinking or vulcanizing during moulding, e.g. in a mould by wave energy or particle radiation
  • B29C35/0866—Heating or curing, e.g. crosslinking or vulcanizing during moulding, e.g. in a mould by wave energy or particle radiation using particle radiation
  • B29C2035/0877—Heating or curing, e.g. crosslinking or vulcanizing during moulding, e.g. in a mould by wave energy or particle radiation using particle radiation using electron radiation, e.g. beta-rays
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
  • B29C2791/00—Shaping characteristics in general
  • B29C2791/001—Shaping in several steps
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
  • B29C35/00—Heating, cooling or curing, e.g. crosslinking or vulcanising; Apparatus therefor
  • B29C35/02—Heating or curing, e.g. crosslinking or vulcanizing during moulding, e.g. in a mould
  • B29C35/04—Heating or curing, e.g. crosslinking or vulcanizing during moulding, e.g. in a mould using liquids, gas or steam
  • B29C35/045—Heating or curing, e.g. crosslinking or vulcanizing during moulding, e.g. in a mould using liquids, gas or steam using gas or flames

Definitions

• the invention relates to a method for fixing winding goods, in the wound state, in particular of non-transparent winding goods, such as wire windings of electrical equipment, such as rotors, stators and transformers, by impregnation (e.g. immersion or trickling) with free-radically polymerizable compositions and subsequent thermal curing.
• the invention also relates to the device for carrying out the method. From DE-A-2 21 619 and DE-A-22 59 161 it is known to coat glass fibers with radically polymerizable monomers and to harden them during the subsequent winding.
• GB Patent 1,160,021 describes the impregnation of glass fibers and products made therefrom, followed by curing by UV radiation.
• the free-radically polymerizable compositions contain, for example, unsaturated polyester resins which are used in unsaturated aromatic or aliphatic free-radically polymerizable monomers, such as. B. styrene or hexanediol diacrylate.
• the object of the invention is to provide methods and impregnants which are suitable for fixing three-dimensional components which have windings, for example wire windings, and which result in a reduced emission of volatile constituents, such as volatile monomers, during thermal curing.
• This object is achieved according to the invention by a fixing method in which the three-dimensional objects to be fixed in wound form are impregnated with free-radically polymerizable compositions and then thermally hardened, but the exposed impregnated surfaces are hardened by high-energy radiation between the impregnation and the thermal hardening .
• this can be achieved in particular by using free-radically polymerizable compositions which contain free-radical initiators as individual compounds or as mixtures which respond both to high-energy radiation and to heat.
• thin films can be formed on the surfaces of the impregnated three-dimensional bodies by means of high-energy radiation, which, during the subsequent thermal curing of the places not accessible to the high-energy radiation, cause the volatile components to escape , especially the volatile monomers, largely prevent.
• the method according to the invention is therefore particularly well suited for winding goods made of ni .
• Highly transparent materials such as electrically conductive wires and non-transparent plastics, which, in contrast to transparent materials, cannot be penetrated by high-energy radiation, such as UV radiation.
• high-energy radiation such as UV radiation.
• it can also be used advantageously on windings made of transparent materials, such as glass fibers or transparent plastic fibers.
• radicalisable (by radical initiation) polymerisable compositions are used, both by high-energy
• radically polymerizable compositions which are both curable by high-energy radiation (for example UV radiation or electron radiation) and thermally.
• high-energy radiation for example UV radiation or electron radiation
• Free radical initiators are those that can be activated both by high-energy radiation and by heat.
• the use of mixtures of radical initiators which are activated by high-energy radiation (photoinitiators) and those which respond to heat is favorable.
• photoinitiators largely depends on the type of radiation with which the surface is to be hardened. For example, it is not necessary to add photoinitiators if the surface is hardened by electron beams.
• Photoim 'tiatoren and thermally responsive initiators are those which are customary in this field.
• photoinitiators which absorb in the wavelength range from 190 to 400 nm
• photoinitiators are chlorine-containing ones
• Initiators such as chlorine-containing aromatic compounds, e.g. Described, for example, in US-A-4 089 815; aromatic ketones as described in US-A-4 318791 or EP-A-0 003 002 and EP-A-0 161 463; Hydroxyalkylphenones as described in US-A-4,347,111, phosphine oxides as described in EP-A-0 007 086, 0 007 508 and 0304 783; water-soluble initiators, for example based on hydroxyalkylphenones, as described in US-A-602 097, unsaturated initiators, such as OH-functional aromatic compounds which have been esterified, for example, with acrylic acid, as in US-A-3 929490, EP-A- 0 143 201 and EP-A-0341 560; or combinations of such initiators, as described for example in US-A-4 017652.
• Initiators such as chlorine-containing aromatic compounds, e.g.
• Preferred examples are 2-methoxy-2-hydroxypropiophenone, benzophenone, thioxantone derivatives, acylphosphine oxides and Michler's ketone.
• the above photoinitiators can be used alone or in a mixture; For example, combinations of phosphine oxides with other customary photoinitiators are preferred.
• the free radical initiators which are sensitive to heat are also conventional initiators which can be used in the field of heat curing of free-radically polymerizable compositions.
• heat-sensitive initiators examples include C-C labile compounds, such as are described in DE-PS 12 19 224; it is 1,2-substituted ethanes of the general formula
• R. and R, aromatic radicals, R, a hydrogen atom or an aliphatic or aromatic radical, R, an aliphatic or aromatic radical and X and Y represent an optionally blocked hydroxyl group and / or halogen.
• 1,2-substituted ethanes which are suitable as initiators for radical polymerization under the addition of heat are those of the general formula
• R OH, -0CH 3 , "OC ⁇ , -CH- ,, -CN, -NH 2 , -Cl, -0Si (CH 3 ) -,, as for example by A. Bletzki and W. Krolikowski in plastics 70 (1980) 9, pages 558-562.
• thermally activatable radical initiators based on 1,2-substituted ethanes are those of the general formula
• radicals R independently of one another can represent hydrogen, or one or more alkyl or alkoxy groups, such as methyl or methoxy groups; and in which the groups R independently of one another represent hydrogen atoms or alkyl groups, for example having 1 to 4 carbon atoms, such as methyl groups or ethyl groups.
• groups R independently of one another represent hydrogen atoms or alkyl groups, for example having 1 to 4 carbon atoms, such as methyl groups or ethyl groups.
• thermally activatable radical initiators are bifunctional initiators of the cyclic Si-Pinacol ether type, such as in Polym. Bull. 16, 95 (1986).
• the thermally activatable initiators can also be used as mixtures.
• peroxides and azo compounds can also be used as initiators. Such compounds are known as photoinitiators and / or as thermally labile initiators. Peroxides and azo-based initiators can therefore be used alone, provided that their properties as photoinitiators and thermally activatable initiators are sufficient. If necessary, they can be mixed with
• Photoinitiators or thermally labile initiators are used.
• examples of usable peroxides are organic peroxides, which are common, for example, as radical initiators in the plastics industry; such as di-t-butyl peroxide, dibenzoyl peroxide, peroxocarboxylic acids such as peroxoacetic acid, peroxodicarbonates such as di-sec-butyl peroxodicarbonate, peroxide esters such as 2-ethylhexanedioic acid tert-butyl perester, hydroperoxides such as cumene peroxide and ketone peroxides such as methyl ethyl ketone peroxide.
• An example of an azo initiator is azobisisobutyronitrile, which can primarily be used as a thermally activatable initiator.
• the initiators are used in the amounts customary for photoinitiators or thermally responsive initiators.
• the total amount of initiators used can be, for example, 0.01 to 20, preferably 0.1 to 10, particularly preferably 0.1 to 5% by weight, based on the total mass.
• the maximum amount that can be added is practically unlimited; it is kept as low as possible for economic reasons.
• the quantitative ratios of photoinitiator to thermally labile initiator can vary within a wide range; for example, they can be 1: 1 to 20: 1, preferably 1: 1 to 10: 1 and vice versa.
• Radically polymerizable compositions which are known to the person skilled in the art as free-radically polymerizable materials can be used as impregnating resin compositions. These can be monomers, oligomers or polymers or copolymers and mixtures thereof.
• radically polymerizable compositions are customary radiation-curable, in particular UV-curable compositions based on monomers, oligomers, polymers, copolymers or combinations thereof, with one or more olefinic double bonds, such as, for example, acrylic acid and methacrylic acid esters, and compounds with one or more vinylic ones or allylic double bonds.
• monofunctional monomers are butyl (meth) acrylate and hydroxyethyl (meth) acrylate
• difunctional monomers are examples of difunctional monomers.
• Hexanediol (di) methacrylate. and dipropylene glycol di (meth) acrylate and examples for tri- and tetrafunctional monomers are trimethylolpropane tri (meth) acrylate and pentaerythritol tri- or tetra (meth) acrylate.
• the term ( meth ) acrylate used here means acrylates and / or methacrylates.
• Examples of vinylically unsaturated monomers are styrene and styrene derivatives, such as divinylbenzene, p-methylstyrene and vinyltoluene.
• allyl compounds are diallyl phthalate and pentaerythritol tri- or tetraallyl ether.
• oligomers or prepolymers are (eth) acrylic functions, all (meth) acrylic polymers, epoxy resin (meth) acrylates e.g. B. reaction products from 2 mol (meth) acrylic acid and commercially available epoxy resins, such as. B. Epicote 828, polyester (meth) acrylates,
• curable products are described in the following references: epoxy (meth) acrylates in EP-A-0033 896, EP-A-0049922 and US-A-4485 123; Urethane (meth) acrylates in EP-A-0053 749, EP-A-0 209684 and US-A-4 162 274; Polyester (meth) acrylates in EP-A-0083 666, DE-A-38 10 140; DE-A-38 20294.
• polymerizable compositions which, in addition to a polymerizable oligomer and / or polymer containing olefinic double bonds, contain one or more olefinically unsaturated monomers as reactive diluents.
• the oligomers and polymers are preferably chosen so that they are soluble in the monomer acting as a reactive diluent.
• Radically polymerisable compositions which contain olefinically unsaturated polyesters and olefinically unsaturated monomers as reactive diluents are particularly suitable. These monomers can be mono- or polyunsaturated. Examples of such monomers are those as stated above. Acryloyl and / or are favorable
• Methacrylolyl compounds Particularly preferred examples of such reactive diluents are hexanediol diacrylate and butanediol diacrylate, which can be used alone or in a mixture together with the unsaturated polyesters.
• polyester resins which are known for this purpose, in particular the so-called imide-containing unsaturated polyesters as described in DE-A-15 70 273, 1770 386 and 28 56 050.
• imide-free polyesters can also be used, as have been known for decades. These unsaturated polyesters are condensation products from polyvalent carboxylic acids, polyhydric alcohols and - if they contain imides -
• polyvalent carboxylic acids are dicarboxylic acids, such as maleic or fumaric acid, citric acid, itaconic acid, optionally in a mixture with saturated or aromatic carboxylic acids, such as succinic or adipic acid, phthalic acid, isophthalic acid,
• Acids can be used in the form of esters, half-esters or anhydrides. There can also be compounds with different functional groups
• Aminoethane carboxylic acid and the corresponding three or four CH_-containing amino alcohols or amino carboxylic acids.
• Suitable diols are, for example
• Hydroxyl groups are, for example, glycerol, trimethylolpropane,
• Trimethylolethane pentaerythritol, dipentaerythritol, tris-ethyl isocyanurate. 0
• the imide-containing unsaturated polyesters suitably contain condensed tetrahydrophthalic acid or its anhydride, which forms a 5-membered imide ring with amino groups.
• the polyesters can also contain monofunctional carboxylic acids, alcohols and / or 5 amines as chain terminators. You can also use saturated and unsaturated oils, e.g. B. hydroxy oils such as castor oil or carboxy 'oils, such as maleate, included.
• the above-mentioned compositions are mixed with the free-radical initiators, in particular the mixture of photoinitiators and thermally activatable initiators.
• the free-radically polymerizable compositions can contain conventional additives, such as pigments, extenders, plasticizing components, accelerators (e.g. metal salts, substituted amines), stabilizers (e.g. hydroquinone, benzoquinone), as are familiar to the person skilled in the art in this field .
• the masses are free from solvents.
• the radically polymerizable compositions can be used, for example, to impregnate wound goods to be stabilized, for example wire windings, in the following manner:
• the already wound material to be impregnated is immersed in the impregnating resin in compliance with, for example, immersion times determined by preliminary tests, or drawn through the impregnating resin in a continuous process.
• the already wound material to be soaked is first evacuated in a vacuum container;
• the soaking agent is introduced into the vacuum container from a storage container.
• the wound objects are not immersed in the impregnating agent, but the polymerizable mass is applied to the substrate by means of nozzles. This can rotate, for example.
• the free-radically polymerizable mass is hardened on the surface of the substrate to be fixed by means of a radiation source which emits high-energy radiation, for example.
• a radiation source for UV light or a radiation source for electron radiation Conventional sources suitable for UV or electron radiation can be used as radiation sources. Examples of suitable radiation sources for UV radiation are high-pressure mercury lamps and medium-pressure mercury lamps.
• the impregnated three-dimensional body is guided past the radiation source for radiation curing, so that the method can be carried out online.
• the article may be, for example, rotating past the radiation source to a uniform radiant exposure to ensure '.
• the treatment with high-energy radiation hardens the resin layer on the surface of the object to be fixed, so that during the subsequent thermal aftertreatment the volatile components escape. the volatile monomers is largely prevented.
• the surface layers can be formed in any thickness without causing disadvantages in the subsequent thermal treatment.
• the practically usable layer thicknesses can be achieved with short reaction times, which correspond to the usual curing times in the field of UV or electron beam curing.
• the subsequent curing takes place through a thermal aftertreatment, which can also be carried out on-line.
• the curing takes place by means of conventional heat curing devices, such as curing ovens, or by
• the temperatures are, for example, in the range from approximately 80 to 180 ° C. with reaction times which vary depending on the system to be hardened, for example from 1 minute to 180 minutes.
• a typical device with which the method according to the invention can be carried out on-line and which also represents an object of the invention is shown in the attached figure. It consists of a conveyor belt that is guided past a radiation source and through a hardening furnace.
• the conveyor belt can e.g. B. be designed as a transport chain. It has devices for receiving the soaked substrates. The devices are particularly preferably designed such that the substrates rotate.
• Winding goods are fixed.
• the method according to the invention can also be applied to other substrates that require thermal curing for fixation.
• the method according to the invention is particularly suitable for fixing wire windings, in particular for fixing electrical windings such as are used in electrical equipment, for example in rotors, stators, transformers, etc.
• the method according to the invention can also be used for fixing winding materials which have metal foils, for example copper foils, in the electrical sector.
• Another area of application is the fixing of winding goods based on glass fibers, plastic fibers and plastic films, whereby these materials can also be non-transparent.
• the method according to the invention largely prevents emissions of volatile monomers by rapidly forming an outer polymer layer.
• the material consumption with the same impregnation quality is greatly reduced, or there is an improved impregnation quality with the same material consumption.
• the method leads to improved economy and / or to a longer service life of the windings under thermomechanical loading.
• a particular advantage of the method according to the invention is that it can be carried out on-line or continuously. The process is particularly environmentally friendly due to the low emissions. Examples:
• thermolab and a photoinitiator are added to the styrenic solution of a mixture of an isophthalic acid polyester with an imide polyester (preparation according to EP 0 134 513) in accordance with the following recipe:
• Copper windings of a rotor, diameter 5 cm, are impregnated with the impregnating resin compound described above (by dipping or trickling) and passed past a UV light source (3 medium-pressure mercury lamps, power 100 W / cm) at a speed of 5 m / min.
• a UV light source 3 medium-pressure mercury lamps, power 100 W / cm
• FIG. 1 A schematic representation of the test facility is shown in FIG. 1,
• the formulation mentioned in application example 1 is mixed with 50 pbw of unsaturated epoxy acrylate (Ebecryl 605, UCB-Chemie) and the proportion of initiator is increased to 7.5 pbw each.
• the epoxy acrylate can be used, for example, against a urethane acrylate (Ebecryl 220, UCB-Chemie) or a polyester acrylate
• DPGDA Dipropylengklykoldiacrylats
• TMPTA trimethylolpropane triacrylate
• PETA pentaerythritol tritetraacrylate
• Table 5 shows the corresponding measurement results for the emission reductions.

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• 1990
  • 1990-07-12 DE DE4022235A patent/DE4022235A1/de not_active Withdrawn
• 1991
  • 1991-07-10 PT PT98280A patent/PT98280A/pt not_active Application Discontinuation
  • 1991-07-12 JP JP3511850A patent/JPH05501734A/ja active Pending
  • 1991-07-12 EP EP91912374A patent/EP0495028A1/de not_active Withdrawn
  • 1991-07-12 WO PCT/EP1991/001304 patent/WO1992001015A1/de not_active Application Discontinuation

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