Classifications

• • 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
  • C08J5/18—Manufacture of films or sheets
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29D—PRODUCING PARTICULAR ARTICLES FROM PLASTICS OR FROM SUBSTANCES IN A PLASTIC STATE
  • B29D7/00—Producing flat articles, e.g. films or sheets
  • B29D7/01—Films or sheets
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
  • C08G63/00—Macromolecular compounds obtained by reactions forming a carboxylic ester link in the main chain of the macromolecule
  • C08G63/02—Polyesters derived from hydroxycarboxylic acids or from polycarboxylic acids and polyhydroxy compounds
  • C08G63/12—Polyesters derived from hydroxycarboxylic acids or from polycarboxylic acids and polyhydroxy compounds derived from polycarboxylic acids and polyhydroxy compounds
  • C08G63/16—Dicarboxylic acids and dihydroxy compounds
  • C08G63/18—Dicarboxylic acids and dihydroxy compounds the acids or hydroxy compounds containing carbocyclic rings
  • C08G63/181—Acids containing aromatic rings
  • C08G63/185—Acids containing aromatic rings containing two or more aromatic rings
  • C08G63/187—Acids containing aromatic rings containing two or more aromatic rings containing condensed aromatic rings
  • C08G63/189—Acids containing aromatic rings containing two or more aromatic rings containing condensed aromatic rings containing a naphthalene ring
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
  • C08K3/00—Use of inorganic substances as compounding ingredients
  • C08K3/01—Use of inorganic substances as compounding ingredients characterized by their specific function
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
  • C08K7/00—Use of ingredients characterised by shape
• • 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
  • B29C55/00—Shaping by stretching, e.g. drawing through a die; Apparatus therefor
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29K—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR MOULDS, REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS
  • B29K2067/00—Use of polyesters or derivatives thereof, as moulding material
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29K—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR MOULDS, REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS
  • B29K2105/00—Condition, form or state of moulded material or of the material to be shaped
  • B29K2105/06—Condition, form or state of moulded material or of the material to be shaped containing reinforcements, fillers or inserts
  • B29K2105/16—Fillers
• • 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
  • C08J2367/00—Characterised by the use of polyesters obtained by reactions forming a carboxylic ester link in the main chain; Derivatives of such polymers
  • C08J2367/02—Polyesters derived from dicarboxylic acids and dihydroxy compounds
• • H—ELECTRICITY
  • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
  • H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
  • H05K1/00—Printed circuits
  • H05K1/02—Details
  • H05K1/03—Use of materials for the substrate
  • H05K1/0313—Organic insulating material
  • H05K1/0353—Organic insulating material consisting of two or more materials, e.g. two or more polymers, polymer + filler, + reinforcement
  • H05K1/0373—Organic insulating material consisting of two or more materials, e.g. two or more polymers, polymer + filler, + reinforcement containing additives, e.g. fillers

Definitions

• Flexible polymeric films have proved to be of great value as insulating films in electrical equipment and machinery.
• biaxially oriented poly ethylene terephalate films are useful in transformer insulation, motor generato insulation, wire and cable insulation and as insulating supports for flexible circuits.
• high stiffness and strengths including resistance to cut-through are important.
• these applications require property retention after exposure to elevated temperatures.
• the manufacturing process requires resistance to soldering melt temperatures found in the wave soldering process.
• Motors, generators, transformers, and wire and cable may also be used where long term (years) of exposure to high humidities (and temperatures) may be a problem. Good hydrolytic stability is necessary. Design of equipment is limited by the present property combination of current materials.
• the resent invention provides a biaxially oriented film of PENBB co- polyester with excellent stiffness, high temperature strength, dimensional stability, and hydrolysis resistance for use as electrical insulation.
• biaxial oriented, heat set films made from PENBB copolyester resin exhibit greater stiffness, strength and higher melting point than films made from polyethylene terephtalate.
• this film has improved hydrolytic stability.
• Such improvements are important to the use of film in electrical insulation applications where high temperatures or humidities may be experienced over long periods of time.
• Such uses might include transformer insulation, motor and generator insulation, flexible circuit substrate, and the ' .ke.
• PENBB as used herein refers to a copolyester containing acid-derived knit of which at least 25 mole % are of the formula:
• the bibenzoate units comprise 40 - 60 mole % of the aci derived units of the copolyester, and at least 80 mole .
• ⁇ of the diol-derived unit are -O-(CH 2 ) 2 -O- (ethylene glycol units) .
• the remaining acid-derived units of thi copolymer are preferably of the formula:
• U.S. Patent No. 3,008,934 discloses copolyesters containing as aci derived units 4,4'-bibenzoate and a host of other dicarboxylates including 2, naphthalic dicarboxylate. It also discloses oriented fibers and films prepared fro these copolyesters, however, biaxially oriented PENBB films are not disclosed envisioned . In particular, those films with improved stiffness (tensile modulu and tensile strength in both MD and TD as well as thermostability, UV stabilit hydrophobicity, dimensional stability and impermeability toward gases i comparison to PET film are not disclosed in U.S. Patent No. 3,008,934.
• the copolyester is obtained by polycondensation of the correspondin diacid or lower dialkyl diester and the corresponding diol. Both component should preferably be employed in roughly equimolar ratios. It may however b advantageous to employ one of the components - especially the diol - in exces for instance in order to influence the reaction kinetics or to serve as a solven
• the polycondensation is carried out according to known processes used e g.
• PET polyethylene terephthalate
• dicarboxylic acid or dialkyldicarboxylate mixture usually about 1 00 mole- % of the dicarboxylic acid or dialkyldicarboxylate mixture are mixed with > 1 0 mole-% of the corresponding d ⁇ ol(s), in the presence of a transeste ⁇ ficatio catalyst, and heated until sufficient lower alkyl alcohol or water has bee removed from the mixture via distillation
• This reaction yields an oligomer or low molecular weight polyester, which is subsequently subjected to polyconden sation, preferably in the presence of a stabilizer and/or catalyst.
• Useful stabilizers and catalysts can be polyphosphates, t ⁇ organyi phosphates, antimony t ⁇ oxide or tetraalkoxy titanate (IV) or mixtures of t ⁇ phenylphosphate and antimony t ⁇ oxide
• a preferred process for the production of such copolyester is described in U S Patent Application Ser No. 07/735, 553 which is incorpora ted herein by reference
• a further increase in molecular weight can be achieved by solid phase polycondensation at a temperature just below the melting poin under vacuum, or a stream of dry air or inert gas.
• the IV value inherent viscosity, a measured in a 1 A weight-ratio mixture of pentafluorophenol and hexafluoroi sopropanol at a concentration of 0.2 g/dl and a temperature of 25 ° C
• the IV value of the PENBB polymer after extrusion be > 0.5 dl/g and preferably > 0.55 dl/g.
• the film composition In order to provide good handling and winding properties the film composition must be such that the surface is rough. This can be achieved b incorporating fine inert insoluble particles into the film
• inert particulates in situ by reactin the metal salt transeste ⁇ fication catalyst with phosphoric acid derivatives in th course of the polycondensation step, which causes fine particulate matter t precipitate in the polymer
• Another method is the addition of fine particles to th monomers before or during polycondensation or to the polymer before extrusion
• Such inert fine particles can be kaolin, talc, silica, carbonates of magnesium calcium or barium, sulphates of calcium or barium phosphates of lithium, calciu or magnesium, titanium oxide, lithium fluoride, carbon black and the organic aci salts of calcium, barium, zinc and manganese. It is also possible to use fin particles made of cross-linked polymers.
• the particles may be of one type o mixtures of several types.
• the shape of the particles can be irregular, flaky spherical or elongated .
• the hardness, density and the color of the particles i immaterial.
• the average size of the particles should be less than 10 ⁇ preferably less than 3 ⁇ m.
• the amount incorporated in the film should in th range of 0.01 % to 2.00 % (by weight), preferably between 0.05 % and 0.8 (by weight) .
• common additives such as flame retarda ⁇ ts, anti-oxidants etc. may be incorpor ted in the composition.
• the polymer melt is extruded through a die onto a chi roll where it solidifies, is then biaxially oriented, heat set, optionally post treate and wound on a roll.
• a multi layer film known methods for coextrusion, in-lin or off-line coating can be used .
• the solidified film as extruded on the chill ro should be obtained in an essentially amorphous state.
• the mel film must be pinned to the chill roll by a known method such as electrostati pinning or vacuum, air knife or the like.
• the biaxial orientation of the film is achieved by stretching the film a elevated temperature in the machine (MD) and traverse direction (TD) . Thi stretching can be either simultaneous or sequential.
• the first stretching step can be in either MD or TD, followed b stretching in the perpendicular direction.
• the orientation in MD can also b achieved in several steps, either one after another prior to stretching in TD, o before and after the TD stretching.
• Preferred temperatures for stretching li between the glass transition temperature and about 30°C above the col crystallization temperature of the PENBB copolymer composition in use (bot temperatures can easily be measured on amorphous films by DSC) .
• the tot stretch ratios (/.) in MD and TD lie between 1 : 2 and 1 : 1 0, preferably betwee 1 : 2.5 and 1 : 5.
• the product of the total stretch ratios should be between 1 to 30 preferably between 5 to 20.
• the heat setting takes place at a temperature between the cold crystalliza- tion temperature and the melt temperature of the copolymer composition.
• the copolyester film for electrical insulation is preferably coated with a primer or surface treated via known methods such as corona, plasma, or flame treatment to improve adhesion to other sheet-like materials such as fiber sheet it might be laminated to or to impregnation resins in insulation applications.
• the film contains up to 5 % inert, opaque, white or colored fillers that render the film opaque, which makes the completed insertion of the slot liner in motor or generator manufacture visually apparent.
• Films according to the present invention used for electrical insulation application typically are about 75-350 ⁇ m thick. In flexible printed circuit applications, a film thickness of about 25-1 50 ⁇ m is typically suitable. A thickness of about 1 5-75 ⁇ m maybe preferable for cable and/or transformer applications. For membrane switches or touch panels, film 20-300 ⁇ m thick may be needed.
• the melt is granulated.
• the granules are white, opaque and crystalline
• An IV value of 0.56 dl/g is determined for the granules (measured at a concen tration of 0.1 g/ml in pentafluorophenol/Heyaf luoroisopropanol [weight ratio 1 : 1 at 25 °C) .
• the granules are further condensed for 20 hours at 240 ° C under vacuu in the solid phase. After this treatment the IV value is 1 .1 dl/g. The meltin point (TJ is 281 °C.
• the PENBB granules are melted in a single screw extruder at temperature of 280 - 320 °C and extruded through a sheet dye onto a cooling roll temperatu re controlled at 30 °C.
• amorphous film is obtained which is clear and transparent.
• This PENB prefilm is then sequentially biaxially oriented (first transversely, then longitudinal ly: 3.5x3.5) at 1 30 °C on a film stretching device .
• a strong clear film i obtained .
• the film is finally heat treated at 260 ° C for 1 0 minutes.
• the annealed biaxially oriented PENBB film produced as above has th following mechanical properties
• This film has a thermal shrinkage of 0.3% in the MD and TD directio when heated for 1 5 minutes at 1 50°C.
• EXAMPLE 2 The dielectric properties of the biaxially oriented film in Example 1 ar measured in comparison to standard commercial PET at 1 kHz, and 50% r.h. :
• biaxially oriented PENBB films according to th invention are superior over common biaxially oriented PET films. laims

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• Chemical & Material Sciences (AREA)
• Health & Medical Sciences (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Medicinal Chemistry (AREA)
• Polymers & Plastics (AREA)
• Organic Chemistry (AREA)
• Engineering & Computer Science (AREA)
• Manufacturing & Machinery (AREA)
• Mechanical Engineering (AREA)
• Materials Engineering (AREA)
• Manufacture Of Macromolecular Shaped Articles (AREA)
• Insulating Bodies (AREA)
• Organic Insulating Materials (AREA)
• Compositions Of Macromolecular Compounds (AREA)

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• 1992
  • 1992-12-09 WO PCT/US1992/010713 patent/WO1994013485A1/en not_active Application Discontinuation
  • 1992-12-09 JP JP6514091A patent/JPH08504469A/ja active Pending
  • 1992-12-09 EP EP93900182A patent/EP0674589A4/en not_active Withdrawn

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