Modification of jute by some low molecular weight glycols and a polyol under thermal treatment

Abstract

Jute fabric/yarn was modified by chemical treatments using ethylene glycol (EG), diethylene glycol (DEG), polyethylene glycol (PEG) of two varieties (PEG400 and PEG1500) and poly(vinyl) alcohol (PVA) in the presence of Al 2(SO 4) 3 as the catalyst employing a pad-dry-cure technique. Controlled prior oxidation of the cellulosic and related chain molecules of jute to dialdehyde and related moieties with the help of aqueous NaIO 4 then enhancing its copper number from 2.3 to 10–13, produced optimum effects considering property improvements. Treatments of oxy-jute so obtained with 8% of the above diol/polyol modifying agents in the presence of 5% Al 2(SO 4) 3 as the catalyst, followed by drying at 95°C for 5 min and curing of the dried fabrics at 125°C for 5 min produced most balanced improvements in the textile related properties such as flexibility as revealed by bending length, wrinkle recovery angle, abrasion resistance, fiber shedding, hairiness, retention of mechanical properties and surface reflectance/gloss. Use of PVA tends to make the fabric somewhat more stiff, which can, however, be satisfactorily controlled if the PVA used is subjected to prior degradation using aqueous NaIO 4. Modification of jute by optimum dose of PEG1500 produced the most improved and balanced effects including notable improvements in tenacity and elongation at break and hence in resilience, feel and texture and substantial lowering in hairiness, bending length and fiber shedding character. Differences in the surface modification of jute fibers effected by use of different glycolic/polyol modifying agents as revealed by scanning electron micrographs have also been discussed.