摘要:
Process for the preparation of powdered thermosetting coating composition suitable for application as paint or varnish on electricity-conducting articles by powder spray methods and fluidized bed coating processes, which comprises: in a first stage, preparing a branched-chain hydroxyl group-containing polyester from at least one dicarboxylic organic acid, at least one polycarboxylic aromatic acid and at least one dihydric organic compound; in a second stage, esterifying the hydroxyl group-containing polyester thus obtained with an aromatic or hydroaromatic dicarboxylic acid to give a carboxyl group-containing polyester having an acid number which is substantially equal to the hydroxyl number of the hydroxyl group-containing polyester obtained in the first stage; and in a third stage, homogenously mixing the carboxyl group-containing polyester obtained in the second stage with an epoxy compound containing at least two epoxy groups, and optionally adding auxiliary substances conventionally used in the manufacture of powdered paints and varnishes; and powdered thermosetting compositions suitable as paint or varnish obtained by this process.
摘要:
Halogen-free flame retardant compositions comprising copolyetherester thermoplastic elastomers, melamine cyanurate and epoxy-containing compounds and cables and wires made from such flame retardant polymer composition provide good electrical insulation resistance during use.
摘要:
The invention relates to a method for in-situ synthesis of silicon nanoparticles in a thermosetting polymeric matrix, the thermosetting and thermoset matrices obtained in this way and a material including same. The method includes the following steps: a) forming an aqueous-phase/organic-phase inverse emulsion, wherein the aqueous phase includes at least a basic catalyst and the organic phase includes at least a non-cross-linked (co)polymer precursor chosen from an aliphatic, cycloaliphatic or aromatic epoxy resin precursor, a polyester-imide precursor, an unsaturated/epoxy polyester (co)polymer precursor, a polyether/epoxy (co)polymer precursor and a polyurethane precursor; b) introducing, into the inverse emulsion formed in step a), at least one silicon precursor forming a complete network whereof the rate of hydrolysis is greater than the cross-linking speed of the (co)polymer and c) stirring the mixture obtained in step b) and heating to a temperature between 20° C. and 70° C.
摘要:
A dielectric block provided in a dielectric antenna is formed with an organic polymer material containing a liquid crystal polymer and polytetrafluoroethylene. The added amount of polytetrafluoroethylene is 2 to 15% by volume based on the volume of the dielectric block. Preferably, the liquid crystal polymer has a flow beginning temperature of no lower than 310° C. and no higher than 335° C. The dielectric block may further contain a dielectric inorganic filler and in this case, the added amount of dielectric inorganic filler is 45% by volume or less based on the volume of the dielectric block.
摘要:
Disclosed is a biaxially oriented film for electrical insulation having even better withstand voltage characteristics than before together with excellent film-forming properties. The biaxially oriented film for electrical insulation of the invention is a film that includes a substrate layer containing a crystalline thermoplastic resin as a main component. The substrate layer contains a phenolic stabilizer in an amount of 0.001 wt % or more and 3 wt % or less based on the weight of the substrate layer. The phenolic stabilizer is an alkylenebisamide-type hindered phenol.
摘要:
A multilayer insulated electric wire includes a conductor and three or more insulating layers covering the conductor. In the multilayer insulated electric wire, the outermost layer (A) of the insulating layers includes a coating layer formed of a resin composition of a polyamide resin containing copper iodide, and the innermost layer (B) of the insulating layers includes a coating layer formed of a resin composition of 100 parts by mass of a polyester-based resin (B1), all or a part of which is formed of an aliphatic alcohol component bonded with an acid component, and 5 to 40 parts by mass of an ethylene-based copolymer (B2) having side chains of a carboxylic acid or a metal salt of a carboxylic acid.
摘要:
An oriented polyester film (A) which comprises modified polyethylene-2,6-naphthalenedicarboxylate containing a 4,4'-diphenyldicarboxylic acid component and having a heat of crystallization of 16 to 25.5 Joule/g, and (B) which is biaxially oriented; and an oriented polyester film (A') which comprises modified polyethylene-2,6-naphthalenedicarboxylate containing of a glycol component derived from a compound represented by the following formula, ##STR1## wherein each of n and m is independently a positive number of 1 to 9 as an average, provided that m+n equals 2 to 9 as an average, and having a heat of crystallization of 6 to 20 Joule/g, and (B) which is biaxially oriented. These films are useful as a base film for a magnetic recording tape or as an electric insulation film.
摘要:
A flame-retarding polyester composition is useful for coating an electric wire, which comprises a melt-mixture of, (A) a copolyester having a halogen content of 0.5 to 30 wt. % and (B) a branched copolymer prepared by the condensation polymerization of monomers mainly comprising(a)' a component mainly comprising an aromatic dicarboxylic acid or an ester-forming derivative thereof,(b)' a component mainly comprising an aliphatic glycol or an ester-forming derivative thereof and(d) a branching compound, which contains 0.001 to 0.5 molar % (based on the total amount of the carbonyl groups of the copolyester) of said branching compound (d).
摘要:
Molding materials, laminates, stratified material and cover or protective layers which are of high electrical and mechanical quality are formed from polymerisable epoxy compounds if the corss-linking of the epoxy resins is accomplished by anionic polymerisation, using mixed catalysts of tertiary amines of the formula: ##STR1## and an imidazoles of the formula: ##STR2## as a polymerisation catalysts.
摘要:
In an article molded from a non-burning, non-dripping filled polyester composition having a high level of arc resistance and tracking resistance, decay in the arc resistance with time is substantially decreased or prevented by incorporating a minor but critical amount of polyethylene terephthalate. Typical compositions comprise (a) approximately 30 to 60 percent by weight, based on the composition, of a mixture of polyethylene terephthalate and polybutylene terephthalate wherein polyethylene terephthalate comprises approximately 3 to 20 percent by weight; (b) approximately 30 to 60 percent by weight of the composition of a mixture of fiber glass and talc wherein talc comprises approximately 15 to 35 percent by weight of the composition; and (c) an effective amount, up to 20 percent by weight of the composition of a flame retardant additive or a mixture thereof. Typical compositions possess superior electrical properties, comparable to those of thermosetting molding resins.