The invention provides a liquid crystal polyester resin which not only has a low-dielectric tangent, but also is excellent in balance between heat resistance and processing stability. The liquid crystal polyester resin comprises: a structural unit (I) derived from an aromatic hydroxycarboxylic acid; a structural unit (II) derived from an aromatic diol compound; and a structural unit (III) derived from an aromatic dicarboxylic acid, wherein the structural unit (I) contains a structural unit (IA) derived from 6-hydroxy-2-naphthoic acid, the structural unit (III) contains a structural unit (IIIA) derived from terephthalic acid, and a structural unit (IIIB) derived from isophthalic acid, the dielectric tangent at a measurement frequency of 10 GHz is 1.50×10.sup.−3 or less, the melting point is 295° C. or more, and the difference between the melting point and the crystallization point is 35° C. or more.

A resin composition containing a liquid crystal polymer (A) and a predetermined polyimide resin (B), wherein the liquid crystal polymer (A) contains at least one repeating structural unit selected from the group consisting of repeating structural units represented by the following formulas (I) to (IV), and a molded article containing the same:

##STR00001##

wherein a, b, and c represent an average number of repeating structural units.

The invention provides a liquid crystal polyester resin which not only has a low-dielectric tangent, but also is excellent in balance between heat resistance and processing stability. The liquid crystal polyester resin comprises: a structural unit (I) derived from an aromatic hydroxycarboxylic acid; a structural unit (II) derived from an aromatic diol compound; and a structural unit (III) derived from an aromatic dicarboxylic acid, wherein the structural unit (I) contains a structural unit (IA) derived from 6-hydroxy-2-naphthoic acid, the structural unit (III) contains a structural unit (IIIA) derived from isophthalic acid and a structural unit (IIIB) derived from 2,6-naphthalenedicarboxylic acid, the dielectric tangent at a measurement frequency of 10 GHz is 1.50×10.sup.−3 or less, the melting point is 290° C. or more, and the difference in temperature between the melting point and the crystallization point is 30° C. or more.

A polymer composition comprising a semiconductive material distributed within a polymer matrix is provided. The semiconductive material includes inorganic particles and an electrically conductive material, the inorganic particles having an average particle size of from about 0.1 to about 100 μm and an electrical conductivity about 500 μS/cm or less. The polymer matrix contains at least one thermoplastic high performance polymer having a deflection under load of about 40° C. or more. The polymer composition exhibits a dielectric constant of about 4 or more and a dissipation factor of about 0.3 or less, as determined at a frequency of 2 GHz.

Disclosed herein are ropes containing bundles of filaments, where each bundle includes at least 70% by volume of liquid crystal polymer filaments, and where at least one bundle includes liquid crystal polymer filaments of at least 10 denier per filament in size. Also disclosed herein are methods of pulling or lifting an object by applying tension to such a rope connected to the object, where the rope is arranged over a sheave or a non-rotating guide surface, and a ratio of a diameter of the sheave or an effective diameter of the non-rotating guide surface, D, to a diameter of the rope, d, is at least 20:1.

An aromatic polyester having a repeating unit represented by formula (1) shown below and a terminal structural unit represented by formula (1e) shown below, wherein the proportion of the terminal structural unit per unit mass of the aromatic polyester is not more than 50 μmol/g.

—O—Ar.sup.1—CO—  (1)

—O—Ar.sup.1—CO—OH  (1e)

(In the formulas, Ar.sup.1 represents a 1,4-phenylene group, a 2,6-naphthylene group or a 4,4′-biphenylylene group. The hydrogen atoms that exist in the groups represented by Ar.sup.1 may each be independently substituted with a halogen atom, an alkyl group or an aryl group.)

The invention provides novel deoxybenzoin-containing polymers exhibiting branched (including hyperbranched) architectures, and related methods and uses thereof.

Compounds derived from biomass, e.g., cellulose and lignins, methods of forming such compounds and polymers and products formed using such compounds.

The present invention relates to a composite sheet comprising a woven fabric consisting of liquid crystal polyester fiber in which one side or both sides of the woven fabric is coated with a coating material comprising a thermoplastic resin, wherein a tensile strength of the composite sheet in a warp direction of the woven fabric is 300 N/cm or more, and wherein a ratio of a mass of the thermoplastic resin to a mass of the woven fabric is 5 to 25% by mass.

Disclosed herein are ropes containing bundles of filaments, where each bundle includes at least 70% by volume of liquid crystal polymer filaments, and where at least one bundle includes liquid crystal polymer filaments of at least 10 denier per filament in size. Also disclosed herein are methods of pulling or lifting an object by applying tension to such a rope connected to the object, where the rope is arranged over a sheave or a non-rotating guide surface, and a ratio of a diameter of the sheave or an effective diameter of the non-rotating guide surface, D, to a diameter of the rope, d, is at least 20:1.