ABSTRACT:The depolymerization of nylon 6 was carried out with various solvents, such as formic acid, hydrochloric acid, and sulfuric acid, followed by heating under reflux for different times. From the polymer dissolved and refluxed in formic acid, degradation products with different ranges of molecular weights were collected by fractional precipitation, with small lots of distilled water added as a nonsolvent. The characterization of different fractions was carried out by the measurement of the viscosity-average molecular weight, the number-average molecular weight, and the number of amino end groups. The presence of the monomer, aminocaproic acid, was confirmed by thin-layer chromatography in the case of hydrochloric acid treated nylon 6. With a strongly acidic ion-exchange resin, the monomer was separated in its purest form, and the melting point was noted.

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Natural coir fibers, subjectd to thermal treatments in the range of 0 o C to 200 o C and alkali treatment with 5% to 30% concentration w/w, have been used in the present investigation to determine the interlayer variability of the cellulose planes (020), (110) and (110). Among the equatorial reflections (110), (110) and (020), the extent of variability is found to be more with the proportion of such affected planes less for (020) reflection in the native cellulose at lower temperature while at higher temperature (110) and (110) become more affected by variability defect. (110) and (1 10) planes are more affected also with alkali treatment.