Kartick K. Samanta

Thermally stable cellulosic paper made using banana pseudostem sap, a wasted by-product

Abstract Fire resisting property was imparted to cellulosic paper by the application of a bio-enriched version of a banana pseudostem sap (BPS) as well as the only BPS, obtained as a byproduct during fibre extraction from the pseudostem. The papers were evaluated for their flame retardant property by measurement of limiting oxygen index and vertical flammability. They were also characterized by thermogravimetry, scanning electron microscopy and energy dispersive X-ray analysis. The bio-enriched BPS treated paper was found to exhibit a better flame retardancy with distinguished char length, compared to the control and the only BPS treated paper. The impartment of flame resisting property to a paper by the BPS, along with its charring behaviour has been discussed and the mechanism thereon has been postulated. The BPS application was found to enhance the oxygen required for the burning of the paper and reduce its burning rate by promoting more dehydration and char formation. The imparted fire retardant finish found durable to weathering, did not cause any significant loss in tear and tensile properties of the paper.

Flame retardant cellulosic textile using bannana pseudostem sap

Purpose – The purpose of this paper is to use the natural wastage plant product, bannana pseudostem sap (BPS) for using as fire retardant of cellulosic textile substrate. The study aims to use first time any wastage plant product for making fire retardant cellulosic textile. In this regard flame retardant functionality was imparted in cellulosic textile using BPS, an eco-friendly natural wastage product. Design/methodology/approach – The extracted sap was made alkaline and applied in pre-mordanted bleached and mercerized cotton fabrics. Flame retardant properties of the control and treated fabrics were analyzed in terms of limiting oxygen index (LOI), horizontal and vertical flammability and total heat of combustion using bomb calorimeter. The thermal degradation and pyrolysis was studied using thermogravimetric analysis (TGA). The chemical composition of the control and BPS treated cellulosic fabric were analyzed by FTIR, SEM and EDX. Durability of the flame retardant functionality to soap washing had al...

Low-temperature dyeing of silk fabric using atmospheric pressure helium/nitrogen plasma

Silk fabric was plasma treated in an indigenously developed atmospheric pressure plasma reactor in the presence of helium and nitrogen (He/N2) gaseous mixture at a discharge voltage of 5 kV and frequency of 21–23 kHz. The samples were plasma treated for 1 to 10 min with a constant nitrogen flow of 50 ml/min. They were also plasma treated in varying nitrogen flow rates in the range of 33.3 to 225 ml/min, keeping a constant helium (He) flow rate at 450 ml/min. The effects of plasma treatment time and nitrogen (N2) gas flow rates on water wicking, physical and chemical properties of the fabric surface along with rate of dyeing were investigated in details. The formation of amine groups in the plasma treated samples helps in faster exhaustion of acid dye even at a lower temperature. It was possible to dye the plasma treated silk fabric at 40 ºC temperature instead of 90 ºC, as is used conventionally. Due to higher dye exhaustion, the plasma treated sample showed a deeper shade. The physical and chemical properties of the samples were analyzed using SEM, ATR-FTIR, secondary ion mass spectrometer (SIMS), and XRD. Results indicate that water took only 408 s and 309 s to travel up to a height of 6 cm in the plasma treated samples for 4 min and 10 min, respectively. This was much shorter as compared to 696 s observed in the untreated (control) sample. The effects of plasma treatment time and the amount of nitrogen (N2) gas flow had a similar effect on water wicking. The plasma treatment time and N2 gas flow rates showed only marginal effects on mechanical properties of silk.

Environment-Friendly Textile Processing Using Plasma and UV Treatment

Wet chemical processing of textiles requires a large quantity of water as a processing medium, which is finally discharged as an effluent contaminated with residual dyes, pigments, and other hazardous chemicals. However, plasma and UV photons can be effectively used for nanoscale surface engineering of various textile substrates while avoiding the usage of water as a processing medium. Plasma- and UV-induced surface activation, oxidation, etching, increase in surface area/roughness, and polymerization of textile substrates have also been utilized for improvement in water and oil absorbency, dyeing, printing, antistatic, and anti felting properties. Specialty fabrics, such as with one hydrophilic side and other side hydrophobic could also be produced by UV treatment. On the other hand, fragmentation of a precursor molecule in the plasma zone leads to in situ plasma reaction resulting in the development of pinhole-free hydrophobic textiles. In plasma and UV treatment, as only the surface of the sample is modified, they require a minimum amount of chemicals and energy. In addition, the cost of the final product can also be reduced due to the shorter processing time, exclusion of multistep operations, and partial reduction in effluent treatment. In the plasma- and UV-treated samples, the dyeing time, temperature, and dye bath auxiliaries can be reduced to achieve similar or better depth of shade compared to the untreated sample without compromising the fastness properties.

Potentials of Fibrous and Nonfibrous Materials in Biodegradable Packaging

Packaging is a, essential requirement for fruits, vegetables, agricultural crops, food products, and other commodities to provide the requisite protection from physical damage, contamination, deterioration; to increase shelf life; and facilitate need-based supply from the producer to the consumer. The packaging material should be physically and mechanically strong and should not add any foul odor to the packed product. In the past, for packaging of the above-mentioned products as well as various industrial goods has been made of traditional to advanced materials such as metal and glass; ordinary, coated, and laminated paper; corrugated paper box; gunny sack; textile bag; bamboo slit; wooden box; biodegradable film; nonbiodegradable plastic/film; composite; and nanocopmosite/biocomposite, all of which have been widely used. During the past 50 years, synthetic polymers have been found to steadily replace traditional packaging materials because of their advantages of low cost, low density, inertness, resistance to microbial growth, thermoplasticity, and transparency. However, their usage currently is being partially restricted because they are not totally recyclable and/or biodegradable and thus lead to serious environmental problem. This has resulted in the development of biodegradable polymers/films such as starch, polylactic acid, protein-based film, poly-beta-hydroxyalkanoates (PHB), etc. It has been possible to enhance physico-mechanical and functional properties of such polymers by incorporating organic and inorganic nanoparticles such as silver, titanium, chitosan, cellulose, clay, starch, silica, and zein. Similarly, traditional to coated/laminated paper/paper board, jute fabric, and the corrugated fibre board have been utilized for conventional to high-end packaging.

Potential of Ligno-cellulosic and Protein Fibres in Sustainable Fashion

Fashion can be encapsulated as the prevailing styles manifested by human behaviour and the latest creations by the designers of textile and clothing, footwear, body piercing, decor, etc. Fashion can trace its history to the Middle East (i.e., Persia, Turkey, India and China). Natural fibres such as silk, wool, cotton, linen, jute and ramie (a flowering plant in the nettle family) and man-made fibres such as regenerated rayon, cellulose acetate, polyester, acrylic, bamboo, and soy protein are intensively used for the production of traditional to specialty apparel, home furnishings and interior decorative textiles. To prepare fibres for use they are enhanced during spinning, weaving, knitting and chemical processing. Linen/flax is considered the most important and useful natural fibre as far as fashion is concerned for tops, shirts and summer dresses. Recently (as of 2016), a few more protein fibres—such as angora, pashmina and yak—have also been exploited to produce luxurious fashionable textiles, owing to their exotic features. Natural fibre–based textiles are being increasingly dyed in a sustainable manner using eco-friendly natural dyes that are fixed by using bio-mordants (plants that accumulate alum in their leaves). Similarly, the potential naturally coloured cotton has for traditional to fashionable end applications is also highlighted in this chapter. As far as sustainable development is concerned, textiles are preferred to be made of natural fibres and to be value-added with eco-friendly chemicals and auxiliaries, preferably derived from natural resources such as plant/herbal extracts, bio-materials, bio-polymers and bio-molecules.

Extraction of natural cellulosic fibers from cornhusk and its physico-chemical properties

A natural long staple ligno-cellulosic fibers have been extracted from the cornhusks using an alkali treatment. Physico-chemical properties such as chemical composition, length, fineness, crystallinity, surface properties, etc. measured by standard methods are reported in this paper. The physico-chemical and morphological properties of the extracted cornhusk fibers are discussed in detail and compared with other cellulosic like cotton and ligno-cellulosic fibers such as jute. Scanning electron microscopy was used to study the morphological and cross-sectional view and energy dispersive X-ray and FTIR were used for the identification and quantification of elements, groups present in the cornhusk and other cellulosic and lignocellulosic fibers. In addition, fibers are characterized by thermo-gravimetric analysis. Results showed that morphological and physico-chemical behavior is more or less similar to other multicellular ligno-cellulosic fibers like jute.

Sustainable Dyeing and Finishing of Textiles Using Natural Ingredients and Water-Free Technologies

Wet-chemical processing of textile substrates starting from its preparatory to dyeing/printing followed by finishing is important for its value addition in terms of aesthetic value, removal of impurities, colour shade, colour pattern and requisite functionality. However, some of the traditional processes are water, energy and chemical intensive. In the recent time, due to global awareness on environmental pollution, climate change, global warming, carbon footprint and sustainability, both the academic research and industrial product development have been intensified to seek for sustainable dyeing and finishing processes, using biomacromolecules, biomaterials, plant extract, biopolymer and water-free technologies. In this context, deoxyribonucleic acid (DNA) from herring sperm, whey proteins, casein, chicken feather protein (CFP), banana pseudostem sap (BPS), spinach juice (SJ) and green coconut shell extract (GCSE) has been explored for improving the thermal stability of cellulosic, lignocellulosic and protein substrates. Similarly, agro-waste, nanolignin, silk sericin and aloe vera have been successfully extracted and applied in textile substrates to protect its user from the harmful ultraviolet (UV) rays. The above natural ingredients and a few more from marigold, manjistha, annatto, neem, turmeric, sandalwood, tulasi, jasmine, lemon, lavender and sandalwood have also been explored for natural dyeing, UV protective, aroma and antimicrobial finishing of textile. Water-less plasma and UV treatment can also be used as a pre-treatment, post-treatment, in situ reaction or post-polymerization for surface activation, oxidation, etching, polymerization, coating and deposition to impart value-added functionalities, such as water and oil absorbency, water and oil repellency, flame retardancy, UV protection, anti-static property and dyeing of various textile substrates.

Recycled Fibrous and Nonfibrous Biomass for Value-Added Textile and Nontextile Applications

Waste is a substance that is considered by all as unwanted or additional material arising out of any industrial or agricultural operation process, product, by-product, or any other item at the end of their requisite service life. In a country such as the United Kingdom, about 4–5 % of municipal solid waste is composed of clothes/textiles, 25 % of which is recycled. A large amount of unutilised/processed material is generated in the agricultural, food processing, paper–pulp, and textile industries as waste or residue, such as lignin, sericin, dyes, sizing paste, leather fibre, banana pseudostem sap, cellulosic and ligno-cellulosic short to long biofibres, corncob, tomato seed and peel, and many others. The disposal of such waste or residue creates serious environmental pollution, either during their natural degradation, through the microbial pathway, or through incineration. As many of the agro, food, textile, and paper–pulp processing wastes or residues have high technical potential to be used for many diversified end-applications, they have been seriously considered through R&D efforts and application for the production of nanocellulose, microcrystalline cellulose, bacterial cellulose, recovery of dyes, water purification, biodegradable hard and flexible composites, substrates for tissue engineering, recycled textiles, UV protective and antimicrobial agents, binder and biodegradable pots for transplanting of plants, and so on. Life-cycle assessment has also been explored to analyse the environmental performances of different shopping bags.

Thermal behaviour and the cone calorimetric analysis of the jute fabric treated in different pH condition

In this paper, the effect of pH, i.e. acid and alkali was investigated on thermal stability of ligno-cellulosic polymeric fibrous (jute) material. The jute fabric was subjected to treatment under different pH, namely 4.5, 7, 10, 12, i.e. in acidic, neutral and alkaline conditions followed by drying prior to any thermal and physical characterization. The improvement in the thermal stability of jute to flame was measured in terms of limiting oxygen index value, vertical flammability and temperature profile of burning zone. Likewise thermo-gravimetry, differential scanning calorimetry and cone calorimeter analysis were also used to elucidate the improvement in thermal stability of the treated fabric. The changes in heat release rate, mass loss rate, heat of combustion, smoke production, etc., in the untreated and treated sample were measured in detail in cone calorimeter. Only the alkali-treated jute fabric samples showed profound improvement in thermal stability.