Structural changes in Tencel by enzymatic hydrolysis

Abstract

ABSTRACT:The NaOH-, fibrillation-, and cellulase-treated Tencel fabrics were characterized by weight loss, tensile strength, scanning electron microscopy (SEM) analysis, X-ray diffraction analysis, measurements of moisture regain and dye adsorption (K/S value), degree of polymerization (DP), and copper number. Weight loss increased and tensile strength decreased with increase in cellulase concentration and treatment time. At a similar weight loss, tensile strength retentions of the NaOH-pretreated samples were better than those of the NaOH-nontreated samples because of more uniform enzymatic hydrolysis. SEM photographs showed more surface peeling and interfibrillar splitting as enzymatic hydrolysis progressed. Crystalline structure and degree of crystallinity were not much changed by cellulase treatment. As enzymatic hydrolysis progressed, moisture regain and K/S value increased slightly due to increase of specific surface area by fibrils. DP initially decreased as enzymatic hydrolysis progressed and then leveled off. Copper number increased largely at an initial stage of degradation and then decreased gradually. The NaOH-pretreated samples showed higher degree of crystallinity, DP, moisture regain, and K/S value, but lower copper number than the NaOH-nontreated ones. These results were attributed to extraction of short chain molecules in the amorphous region during NaOH pretreatment and change of amorphous region into the open-up structure.

Barium sulfate/regenerated cellulose composite fiber with X-ray radiation resistance

“…No other new peak emerged, implying the low interaction between BaSO 4 particles and viscose matrix. reflection of cellulose II crystallite structure, respectively [17][18][19]. The diffraction peaks at 23.5 , 26.6 , 29.5 , 32.2 , and 43.7 were the characteristic peaks of orthorhombic BaSO 4 crystal, identical with that reported in the study by Ramaswamy et al [16].…”

Electrospinning of thermo-regulating ultrafine fibers based on polyethylene glycol/cellulose acetate composite

“…In 1995, Pause managed to coat fibers with microencapsulated PCM (microPCM) and systematically studied the basic and dynamic thermal insulation of the fabrics using a range of different PCMs [4]. However, the surface coated fabrics became rougher and stiffer as the amount of microPCM increased, and thus the total hand value, which determines the tactile comfort perceived by humans, decreased [7]. Recently, Zhang et al successfully prepared thermo-regulating composite fibers by embedding the microPCM into the fibers via both melt-spinning [8] and wet-spinning [9] techniques.…”

Apparent Induction of Xylanase by Bacillus pumilus PU4-2 using Pretreated Substrates

“…It was reported that pretreatments, especially soaking in sodium hydroxide, enhanced the cellulase production (Purwadaria et al 2004b). This result correlated with lignocellulose content that had been altered by sodium hydroxide where it breaks the lignin shield and disrupts the crystalline structure of cellulose (Shin et al 2000;Mosier et al 2005). Soaking pollard in water might reduce the reducing sugar availability in pollard or decrease the catabolite repression of enzymes.…”