NOPR Community:

Electrical behaviour of sisal fibre

Sun, 01 Dec 1991 00:00:00 GMT

Title: Electrical behaviour of sisal fibre Authors: Chand, Navin Abstract: Electrical properties such as dielectric. constant, dissipation factor and resistivity of sisal fibre have been determined. Resistivity increases from 5.5 x 10¹⁰ to 8.09 x 10¹⁰ ohm cm with the increase in voltage from 22 to 145 V. A mechanism of conduction in this fibre is proposed. Page(s): 287-288

Configuration of thick places in rotor-spun polyester yarn

Sun, 01 Dec 1991 00:00:00 GMT

Title: Configuration of thick places in rotor-spun polyester yarn Authors: Ishtiaque, S M; Saxena, Ajay Kumar Abstract: A new technique for classifying thick places by their configuration is proposed. Using this technique the thick places in a 24 tex polyester yarn have been classified into four categories. The technique has been found to be very useful in determining the stage at which thick places increase and in correcting the situation. Page(s): 285-286

Synthesis of 2-(aryl/hetaryl)azo-3,4-dihydroxy-5-( 4-nitrophenyl)- thiophene-1, 1-dioxide derivatives and their dyeing properties

Sun, 01 Dec 1991 00:00:00 GMT

Title: Synthesis of 2-(aryl/hetaryl)azo-3,4-dihydroxy-5-( 4-nitrophenyl)- thiophene-1, 1-dioxide derivatives and their dyeing properties Authors: Mavlankar, S V; Rangnekar, D W Abstract: Preparation of 2-(aryl/hetaryl)azothiophene derivatives (VIa-g) was achieved by coupling 3,4-dihydroxy-5-(4-nitrophenyl)-thiophene-1, 1-dioxide-2-carboxylic acid (III) with diazonium salts (Va-g) derived from aryl and hetaryl amines (IVa-g).The intermediate III was obtained in excellent yield by the condensation of diethyl oxalate and 4-nitrobenzylsulphonyl acetic acid in a single step. These compounds when applied on polyester fibres as disperse dyes gave yellow to red-violet shades with good pick-up, moderate light fastness and good sublimation fastness. Page(s): 282-284

Synthesis and dyeing characteristics of 2-(aryl/hetaryl)- styryl-8-dicyanomethyleneindeno[1,2-d]thiazoles

Sun, 01 Dec 1991 00:00:00 GMT

Title: Synthesis and dyeing characteristics of 2-(aryl/hetaryl)- styryl-8-dicyanomethyleneindeno[1,2-d]thiazoles Authors: Rangnekar, D W; Mavlankar, S V Abstract: 2-Methyl-8-dicyanomethyleneindeno[1,2-d]thiazole(III) obtained by the condensation of 3-dicyanomethyleneindan-1-one(II) with thioacetamide in presence of idodine and dimethylsulphoxide was reacted with different aryl and hetaryl aldehydes (IVa-e) to give 2-(aryl/hetaryl)-styryl-8-dicyanomethyleneindeno[1,2-d]thiazoles (Va-e). These compounds when applied as disperse dyes on polyester fibres showed good pick up, moderate light fastness and excellent sublimation fastness. Page(s): 279-281