Sorption and densitometric properties of meta/para-aramid fibres

Sorption of water vapors was investigated and the specific surface area and density of samples of Tverlan and Arlan fibres, initial and undergoing treatments, were determined. Both fibres are sufficiently hydrophilic. Slow kinetics of absorption of water vapors by Tverlan and Arlan fibres was observed; it can be explained by the lability of these fibres due to the presence of benzimidazole constituents. The Tverlan and Arlan fibres investigated have close specific surface areas. The presence of DMAA in the fibre reduces sorption of water vapors, probably due to blocking of the functional groups of the fibre. After treatment with 70% aqueous solution of DMAA and ordinary washing, an important amount of DMAA remains in the fibre, and more remains in Arlan than in Tverlan.