Investigation of Dimensional and Physical Properties of Eri Silk Bi-Layer Knit Fabrics for Active Wear Applications

The knitwear industry caters to the needs of the modern youth, whose preferences vary according to the trends and tastes of the modern age. This paper endeavors to demonstrate that active wear fabrics made of eri silk have very good physical properties. The main objective of this research is to investigate dimensional and physical properties of plated interlock, mini-flatback rib, and flatback rib structures developed with two different yarn counts (30s and 40s). The dimensional and physical properties of those samples are investigated in terms of dimensional stability, spirality, bursting strength, elongation percentage, fabric areal density, and fabric thickness. Variables such as yarn count and knit structure play a significant role on the dimensional and physical properties of the fabric.

The effect of raw material combination, yarn count, fabric structure and looplength on the thermal properties of Eri silk bi-layer knitted fabrics

Eri silk is one of the wild silk varieties which are mainly available in the north-eastern areas of India. It exhibits goodmechanical and thermal resistance properties. In this concern, the present study focused to develop a bi-layer knittedstructure made from Eri silk yarn as one side(next to skin) and on another side bamboo yarn knitted fabric. Similarly,Tencel knitted fabric was used instead of bamboo. Twenty-four bi-layer knitted fabrics were developed and thenanalysed for its thermal comfort property. The air permeability, and wick-ability were found to be higher and the thermalresistance was found to be higher for bi-layer plated interlocked knitted fabric made out of Eri silk compared to bambooand Tencel.

In-Situ Polymerization of Maleic Acid in Presence of Aloe vera Gel for Development of Eco-Friendly Eri Silk based Handlooms

Polycarboxylic acid compounds such as butane-tetra-carboxylic acid, cyclopentane-tetra-carboxylic acid, and citric acid offer an environmentally friendly, non-toxic, and safe alternative to toxic formaldehyde condensate resin as a silk cross-linking agent. However, the sodium salts of phosphorus-containing mineral acids used as esterification catalysts with such polycarboxylic acids are not environmentally friendly because of their reported adverse effects on the aquatic environment and soil. Also, finishes based on such non-polymeric polycarboxylic acids cannot retain or improve the strength and moisture-regain characteristics of silk. Moreover, most polycarboxylic acids are too expensive for practical exploitation. In view of the above, the present work was aimed at establishing the optimum condition for the application of vinyl monomer containing carboxylic acid like maleic acid in presence of initiator and catalysts on silk fabric in the presence of ammonium persulphate as the free radical polymerization catalyst and trisodium citrate as the esterification catalyst. In this study, eri silk-based handloom fabrics were finished with Aloe vera gel and maleic acid as a cross-linking agent using the pad-dry-cure method. Water-soluble Aloe vera gel with varying concentrations of 5 to 15% (w/v) was also added in the finishing bath to add antibacterial activity to the fabric along with the anti-crease properties. Evaluation of attainable changes or improvements in the eri silk based handloom fabric properties in respect of tensile strength, wrinkle recovery, flexibility, antimicrobial, porosity and moisture regain on such treatments have been done. Besides this, changes in the chemical nature of silk fabric on such modifications have been studied by infrared (IR) spectroscopy and reported in this research article. The study proposes thermal curing system is conducive for in-situ polymerization of maleic acid in presence of Aloe vera for the development of eco-friendly eri silk based handlooms with antibacterial and anti-crease properties, without a significant loss in strength properties. The effects of the antimicrobial agent were assessed even after the 10 wash cycle.

Structural and Thermal Properties of Ethiopian Eri and Mulberry Silk Fibres

Silk fibre has received attention in the biomedical sector rather than textile production because of its excellent biocompatibility properties in the past century. Although silk fibre properties are different from area to area, it has created an opportunity in the biomedical sector to develop new silk-based medical textile products. This research work aimed to study the structural, physical, mechanical, and thermal properties of Ethiopian silkworm cocoon’s filament. Eri and mulberry silk fibre properties such as morphological structure, chemical properties, linear density, filament length, tensile strength, elongation, thermal property, and luster were measured using ES ISO and ASTM standard methods. Statistical analysis result showed that eri silk fibre from Arba Minch had water removal temperature between 100°C and 125°C with a degradation temperature of around 400°C and eri silk fibre from both Addis Ababa and Awassa had an almost similar water removal temperature around 100°C and degradation temperature around 420°C. Tensile strength and elongation of both eri and mulberry silk fibres had significant differences among each region. The highest tensile strength of 4.47 cN was observed from Addis Ababa, and the highest elongation of 20.01% was found from the Arba Minch eri silk fibre. The coarser linear density of 2.496 dtex from Arba Minch and finer count of 2.392 dtex were exhibited from Awassa. Arba Minch eri silk fibre had the highest filament length of 403.04 m and the least fibre length of 399.2 m recorded at Addis Ababa, and a better whiteness (Rd) value of 58.21 was observed at Arba Minch eri silk fibre. Bivoltine and multivoltine mulberry silk fibres had an average tensile strength of 8.01 and 11.83 cN, elongation of 10.3 and 12.1%, fineness of 3.2 and 3.16 dtex, and filament length of 1208.6 and 1028.26 m, respectively, in the same place of Arba Minch. The morphological structure of eri silk fibre from each region had an almost smooth and clean surface, but bivoltine and multivoltine mulberry silk fibres were somehow rough and had spots. According to the comparison results, Ethiopian silk fibres can be utilised more in the biomedical application and competitive in the global market.

Functional Finishing of eri silk and its union fabrics for hydrophobicity

A novel approach was attempted for the functionalization of eri and its union fabrics with polymers for water repellency finishes. For the study, eri fabric was prepared with plain weave structure using 1/140s and 2/140s (warp and weft directions) and 2/140s of eri and 1/56s of wool yarn for the union fabric in both the warp and weft directions. For surface enrichment, silicone polymer was applied by the pad-dry-cure method. The untreated and treated fabric was evaluated for its hydrophobicity like the water contact angle and spray test, air permeability and physio-mechanical properties viz., counts, GSM, thickness, bending length, crease recovery, tensile strength and elongation were assessed. Analytical tests like UPF, whiteness, brightness, yellowness index for surface appearance was evaluated and SEM was performed. The marginal enhancement in bending length was observed in treated eri silk and union fabrics in both directions. The properties like thickness, brightness, yellowness, increased after application of silicone polymers, while crease recovery decreased. Noticeable enhancement of water contact angle was observed in eri silk and union fabric after adding silicone polymer and UPF was found to be excellent. There was no structural damage observed in all treated samples which are cleared from the Scanning Electron Microscope view. Application of silicone polymer on eri silk and its union fabrics improved the hydrophobic characteristic. The UPF protection properties were evaluated on both fabrics and recorded excellent UPF. In this study, the functional properties on eri silk and union fabrics were achieved successfully for functional clothing and textiles