The Dow Chemical Company

Ashish Sen

Susan J Babinec

Chieh-Chun Chau

Yoshihiko Teramoto

Daniel Bernardo Roitman

Ritchie A Wessling

Ray E Drumright

Richard Allen Lundgard

George J Quarderer, Jr

Robert D Mussell

Ying Hung So

Steven Rosenberg

Steven J Martin

Katsuya Tani

Myrna Serrano

Timothy L Faley

Willie E Rochefort

Masaru Nakagawa

Kazunori Katoh

Katsuhiko Kato

A doped intrinsically-conductive polymer having a conductivity of at least about 10,Siemens/cm (S/cm); which is doped with at least two different dopants, including a &ldquo;short-chain dopant&rdquo; having a molecular weight of less than 1,000 and a &ldquo;long-chain dopant&rdquo; which is polymeric and has a weight average molecular weight of greater than 2,000.

Electronically-conductive polymers

A process for preparing an electronically-conductive thermoplastic composition having at least two phases, which includes (A) combining an amorphous or semi-crystalline thermoplastic polymer or miscible blend of polymers with an electronically-conductive carbon under conditions sufficient to disperse the conductive carbon, thereby forming a mixture having at least one phase, with at least 60 percent of the carbon dispersed in a first phase which comprises at least 90 percent by weight of the mixture; and (B) combining the mixture obtained from step (A) with an amorphous or semi-crystalline thermoplastic polymer or miscible blend of polymers, at least a portion of which is immiscible in the first phase, thereby forming a composition having at least two phases. Compositions prepared by this process are sufficiently conductive to be useful for a variety of applications, such as structural materials for applications requiring electromotively-paintable substrates.

Thermoplastic polymer compositions with modified electrical conductivity

Described is a method for preparing a polybenzazole filament which comprises extruding a polybenzazole dope filament, drawing the filament across an air gap, coagulating and washing the filament, and drying the filament, characterized in that a solution of a compound selected from the group consisting of ferrocenes, ruthocene, iodide-, cobalt-, and copper-containing compounds, dyes, and mixtures thereof is contacted with a filament subsequent to the washing step and prior to the drying step. This method provides a means to improve the tensile strength retention of damaged polybenzazole filaments following exposure to sunlight.

Polybenzazole fibers having improved tensile strength retention

Described is a continuous process for removing polyphosphoric acid from a polybenzazole dope filament, which comprises: (a) contacting the dope filament with water or a mixture of water and polyphosphoric acid under conditions sufficient to reduce the phosphorous content of the filament to less than about 10,000 ppm by weight; and then (b) contacting the dope filament with an aqueous solution of an inorganic base under conditions sufficient to convert at least about 50 percent of the polyphosphoric acid groups present in the filament to a salt of the base and the acid. It has been discovered that contacting the dope filament with a solution of a base after washing the filament to remove most of the residual phosphorous advantageously leads to an improvement in the initial tensile strength of the filament, as well as improved retention of tensile strength and/or molecular weight (of the polybenzazole polymer) following exposure to light and/or high temperatures.

Process for the preparation of polybenzazole filaments and fibers

Fibers spun from polybenzazole dopes can quickly be washed to remove polyphosphoric acid by a combination of initially washing with an acidic liquid and second washing with a hot leaching fluid at at least about 60. The process can reach acceptable residual phosphorous levels (1500-2000 ppm) in as little as about 2 or 3 minutes.

Process for coagulation and washing of polybenzazole fibers

Polybenzazole polymer dopes are spun through a spinneret having more than 2 per cm.sup.2, of orifices in relatively close proximity. The dope filaments formed, then pass through an air gap which has a temperature of 50.degree. to 100.degree. C. and a gas flow sufficient to uniformly reduce the temperature of the dope filaments. The filaments cool in the air gap and are then coagulated.

Method for rapid spinning of a polybenzazole fiber

Growing community of inventors

Midland, MI, United States of America

Ashish Sen