Development of ecofriendly biocomposites to replace non-biodegradable synthetic fibre composites for optimum performances is the main objective of this study. To highlight biocomposites as suitable ...replacements, polyethylene terephthalate matrix composites reinforced with blended water retted and surface alkali treated Entada Mannii fibre particulates and carbonised tropical almond shell ash (TASA) were synthesized by mould casting. The efficacy of water retting as a means of extracting fibres from Entada Mannii plant and fibre modification using NaOH of varying concentration on the mechanical properties of Entada Mannii fibre particulates – PET composites were investigated. Mercerization enhanced the surface properties of Entada Mannii fibres and thus led to better bonding between it and the matrix. Hybrid composites from untreated Entada Mannii fibre particulates and tropical almond shell exhibited the highest hardness of 41.09 BHN. 4% NaOH treated fibre particulate hybrid composites exhibited tensile strength (4.795MPa), flexural strength of 6.09MPa, hardness value of 37.63 BHN, and impact energy of 21.49J compared to the 6% NaOH treated fibre particulate hybrid composites.
Mercerization had been widely used in the textile industry because of its simplicity and ability to improve the luster, strength, and dyeing properties of cotton fabrics. However, the water transfer ...behavior of mercerized cotton fabrics had not been systematically investigated. In this work, cotton fabrics were treated with different concentrations of alkali (130 and 260 g/L) for structural characterization (scanning electron microscopy SEM, Fourier transform infrared FTIR), water absorption (vertical wicking height), moisture absorption (moisture return rate), water retention, and so forth, and were compared with industrial mercerized cotton. It meant that water absorbency and water holding capacity of mercerized cotton textiles were improved by reducing surface impurity, increasing amorphous region, and increasing the number of free hydroxyl groups. It was easier for water molecules to move through the fabric as the vertical wicking height increased. Research showed that the water absorption and water transfer properties of cotton fabrics were related to the alkali concentration in the mercerized treatment, and a comparison with industrial mercerized cotton also proved this point. It also showed that the amount of tension had an effect on water transfer in the fabric, which provided further precision in regulating the mercerization process, improving the thermal comfort of mercerized fabrics, and achieving the aim of regulating the mercerization process according to market demand and environmental influences.
Schematic diagram of the effect of mercerization on cotton fibers.
Mercerization can improve the utilization rate of dyes in the dyeing process, and reduce the discharge of washing wastewater. However, the effect and mechanism of mercerization is not clear on ...digital inkjet printing of cotton fabric. In this work, two kinds of cotton fabrics (original and mercerized) were used for reactive dye digital inkjet printing, and the color improvement mechanism of caustic soda mercerization was investigated. It was found that the crystallinity of cotton fibre was adjusted from 73.9% to 58.5% by caustic mercerization, and the breaking strength did not decrease compared with original cotton fibre. Thus, the accessible reactive hydroxyl groups and the wettability were enhanced for treated cotton fibres, which promoted the inks' wick into the fibres. Interestingly, the penetration of ink droplets between the yarns and fibres after caustic mercerization was decreased, thus the dyes mainly gathered on the surface of cotton fabric. The cotton fibres' cross section structure changed from flat oval to round, which increased the contact area between reactive dyes and fibres. At a certain amount of ink, the optimal
K
/
S
value of 23.47 was achieved for treated cotton fabrics, which was higher than that of untreated cotton fabrics (17.15). Meanwhile, the printed fabrics displayed good washing fastness, rubbing fastness and glossiness. This work has important theoretical guiding significance for producing high quality mercerized cotton fabric digital printing products and reducing printing wastewater discharge.
Mercerization can control the crystallinity of cotton fiber, promote the absorption of ink droplets' wick into the fiber and inhibit ink droplets from penetrating the back of fabric. Therefore, the printing quality was extremely enhanced.
Textile wastewaters are rated as one of the most polluting in all industrial sectors, and membrane separation is the most promising technology for their treatment and reuse of auxiliary chemicals. ...This study evaluates the performance of three types of tubular ceramic ultrafiltration membranes differing by mean pore size (1, 2 and 500 kDa) treating textile mercerization wastewater from a textile mill at different operating conditions: cross-flow velocity (CFV) and temperature. Acceptable results were obtained with 1 kDa ceramic membrane, with rejection efficiencies 92% for suspended solids, 98% for turbidity, 98% for color and 53% for total organic carbon at 20°C and 3 m s
−1
CFV. Highest fouling effect was observed for 500 kDa membrane and lowest CFV. According to the observed results, 1 kDa membrane could be used for the treatment of wastewater from the textile mercerization process in terms of permeate quality.
The properties of cellulose nanocrystals with allomorph II (CNC-II) vary with the sources and the treatments received. In this work, the influences of hydrolysis time, temperature, and the applied ...acid concentration on the crystal size of CNC-II were investigated by the surface response experimental design. The results showed that temperature was the most significant factor affecting the crystal size of CNC-II during hydrolysis from mercerized cellulose. Then the morphology and colloidal properties of CNC-II were revealed by dynamic laser scattering (DLS), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), transmission electron microscopy (TEM), thermogravimetric analysis (TGA), etc. XRD results indicated that CNC-II had slightly lower crystallinity (80.89 % vs 82.7 %) and larger crystallite size (5.21 vs. 5.13 nm) than CNC-I. TEM and AFM results showed that the morphology of CNC-II were disc-like and rod-like particles, with an average diameter of 14.6 ± 4.7 nm (TEM) and a thickness of 4– 8 nm (AFM). TG and XPS revealed the reduced thermal stability was due to the introduced sulfate groups in CNC-II during hydrolysis. This investigation has addressed the features of CNC-II derived from mercerized cellulose, and it would be promising in fabricating advanced materials.
•Hydrolytic pattern of mercerized cellulose was reveled by response surface methodology.•Disc-like cellulose nanocrystals with polymorph II (CNC-II) were obtained.•CNC-II retains an average diameter of 23.6 ± 4.9 nm and a thickness of 4– 8 nm.•Disc-like CNC-II demonstrate distinctive morphological and colloidal properties from CNC-I.
•We study the graft copolymerization of cellulosic Grewia optiva fibers using vinyl monomer.•We examine the effect of redox initiator and microwave radiation on the grafting degree.•Optimization of ...different reaction parameters such as reaction time, concentration of initiator, and solvent.•Study the effect of feed composition of monomer on grafting degree.•Study of physico-chemical and thermal properties of graft copolymers.
Cellulose is the most abundant natural polysaccharide polymer, which is used as such or its derivatives in a number of advanced applications, such as in paper, packaging, biosorption, and biomedical. In present communication, in an effort to develop a proficient way to rapidly synthesize poly(methyl acrylate)-graft-cellulose (PMA-g-cellulose) copolymers, rapid graft copolymerization synthesis was carried out under microwave conditions using ferrous ammonium sulfate–potassium per sulfate (FAS–KPS) as redox initiator. Different reaction parameters such as microwave radiation power, ratio of monomer, solvent and initiator concentrations were optimized to get the highest percentage of grafting. Grafting percentage was found to increase with increase in microwave power up to 70%, and maximum 36.73% grafting was obtained after optimization of all parameters. Fourier transforms infrared spectroscopy (FT-IR), scanning electron microscopy (SEM) and thermogravimetric analysis (TGA/DTA/DTG) analysis were used to confirm the graft copolymerization of poly(methyl acrylate) (PMA) onto the mercerized cellulose. The grafted cellulosic polymers were subsequently subjected to the evaluation of different physico-chemical properties in order to access their application in everyday life, in a direction toward green environment. The grafted copolymers demonstrated increased chemical resistance, and higher thermal stability.
Size and properties of tubular bacterial nanocellulose (BNC) can be regulated by controllable mercerization with thinner tube walls, better mechanical properties, and improved biocompatibility. ...Although mercerized BNC (MBNC) conduits have considerable potential as small-caliber vascular grafts (<6 mm), poor suture retention and lack of compliance that cannot match natural blood vessels increase the difficulty of surgery and limit potential clinical application. Polyvinyl alcohol (PVA) is a kind of hydrophilic polymer with good biocompatibility and elasticity, which can precipitate in alkaline solutions. In this study, novel elastic mercerized BNC/PVA conduits (MBP) are manufactured combining mercerization of BNC tubes with precipitation and phase separation of PVA with thinner tube wall, improved suture retention, better elasticity, good hemocompatibility and great cytocompatibility. The MBP obtained with 12.5 % PVA is selected for transplantation in a rat abdominal aorta model. For 32 weeks, normal blood flow is observed using Doppler sonographic inspection, which demonstrates long-term patency. Immunofluorescence staining results also indicate the formation of endothelium and smooth muscle layers. The results indicate the introduction of PVA, and its phase separation into mercerization of tubular BNC can endow MBP conduits with better compliance and suture retention, making it a promising candidate for blood vessel replacement.
•Mercerized BNC/PVA conduits (MBP) were produced via mercerization of BNC with PVA.•Superior suture retention and compliance were endowed on BNC-based conduits.•MBP conduits exhibited nice hemocompatibility in absence of anticoagulant compound.•MBP conduits satisfied a long-term patency over 32 weeks in rat abdominal aorta.
Naturally occurring plant cellulose, our most abundant renewable resource, consists of fibers of long polymer chains that are tightly packed in parallel arrays in either of two crystal phases ...collectively referred to as cellulose I. During mercerization, a process that involves treatment with sodium hydroxide, cellulose goes through a conversion to another crystal form called cellulose II, within which every other chain has remarkably changed direction. We designed a neutron diffraction experiment with deuterium labelling in order to understand how this change of cellulose chain direction is possible. Here we show that during mercerization of bacterial cellulose, chains fold back on themselves in a zigzag pattern to form crystalline anti-parallel domains. This result provides a molecular level understanding of one of the most widely used industrial processes for improving cellulosic materials.
The objective of this research is to optimize the alkaline treatment variables, including sodium hydroxide (NaOH) concentration, soaking, and drying time, that influence the mechanical behavior of ...bamboo fiber-reinforced epoxy composites. In this study, a Box–Behnken design (BBD) of the response surface methodology (RSM) was employed to design an experiment to investigate the mercerization effect of bamboo fiber-reinforced epoxy composites. The evaluation of predicted tensile strength as a variable parameter of bamboo fiber (Bambusa vulgaris) reinforced epoxy composite structures was determined using analysis of variance (ANOVA) of the quadratic model. In this study, a total of 17 experiment runs were measured and a significant regression for the coefficient between the variables was obtained. Further, the triangular and square core structures made of treated and untreated bamboo fiber-reinforced epoxy composites were tested under compressive loading. It was found that the optimum mercerization condition lies at 5.81 wt.% of the NaOH, after a soaking time of 3.99 h and a drying time of 72 h. This optimum alkaline treatment once again had a great effect on the structures whereby all the treated composite cores with square and triangular structures impressively outperformed the untreated bamboo structures. The treated triangular core of bamboo reinforced composites gave an outstanding performance compared to the treated and untreated square core composite structures for compressive loading and specific energy absorbing capability.
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