Feasibility of Producing Core-Shell Filaments through Fused Filament Fabrication

Fused filament fabrication is a technology of additive manufacturing that uses molten thermoplastics for building parts. Due to the convenient shape of the raw material, a simple filament, the market offers a great variety of materials from simple to blends of compatible materials. However, finding a material with the desired properties can be difficult. Making it in-house or using a material manufacturer can be costly and time-consuming, especially when the optimum blend ratios are unknown or new design perspectives are tested. This paper presents an accessible method of producing core-shell filaments using material extrusion 3D printing. The printed filaments are characterised by a polycarbonate (PC) core and acryl butadiene styrene (ABS) shell with three material ratios. Their performance was investigated through printed samples. Additionally, the material mixing degree was studied by varying the extrusion temperature, nozzle feeding geometry, and layer thickness. The influence of all four factors was evaluated using a graphical representation of the main effects. The results showed that a core-shell filament can be processed using a 3D printer with a dual extrusion configuration and that the mechanical properties of the samples can be improved by varying the PC–ABS ratio. This research provides an accessible method for developing new hybrid filaments with a predesigned structure using a 3D printer.

Investigation of 1-Hexanol Diesel Blends on Performance, Combustion and Emission Characteristics of a Diesel Engine

The most potential long-term and renewable substitute of mineral diesel are biofuels. The growth and degradation of energy resources have an enormous influence on the long-term viability of the human community. Alcohols are gaining prominence in the current renewable energy scenario due to their ease of manufacturing and fuel characteristics. In this investigation, hexanol-diesel blend ratios (up to 20% v/v) is taken into account for this investigation in a single cylinder, water cooled, unmodified 4-stroke DI diesel engine. The increase in 1-hexanol volume content correlates to an improvement in combustion thereby promoting brake thermal efficiency. The greater concentration of oxygen in 1-hexanol reduces emission viz. HC and CO and increases value of NOx. Current investigation recommends a feasible option to substitute ULSD for the capabilities of 1-hexanol.

Preparation of sodium alginate/polyvinyl alcohol composite nanofiber membranes for adsorption of dyes

In this research, electrospinning was used to prepare sodium alginate (SA)/polyvinyl alcohol (PVA) composite nanofiber membranes. Effects of electrospinning parameters on the morphology and fiber diameter were investigated, and an orthogonal design was chosen to optimize the parameters. The optimized nanofiber membranes were applied as an adsorbent for the removal of methylene blue (MB), basic fuchsin (BF), and methyl orange (MO). Kinetic and isotherm of adsorption and effects of different experimental conditions such as pH, contact time, and initial dye concentration on adsorption capacity were investigated. It was found that the optimum parameters for the nanofiber membranes were SA/PVA blend ratios (3:7), electric field strength (20 kV), flow rate (0.05 mL/h), and distance (12.5 cm) between the syringe needle and collector, and the mean fiber diameter of the optimized membranes was 99.58 nm. The adsorption of nanofiber membranes was well described by the pseudo-second-order adsorption kinetic model and the Langmuir model, indicating that the adsorption mechanism was chemisorption by a monolayer. Based on the Langmuir model, the adsorption capacities for MB, BF, and MO were 9.25 mg/g, 9.02 mg/g, and 7.35 mg/g, respectively.

Effect of blending ratio on the hollow coffee carbon polyester/cotton blended yarn

The effect of blending ratio on the performance of hollow coffee carbon polyester/cotton blended compact siro-spun yarn was investigated. Five blend ratios of hollow coffee carbon polyester/cotton fiber (i.e. 20/80, 35/65, 50/50, 65/35, and 80/20) and polyester/cotton fiber 35/65 were designed, and six groups of 14.6 tex yarn were spun by compact siro. Indices for the performance of the yarn (surface morphology, evenness, hairiness, tensile property, and hydroscopicity) were tested and analyzed. The regression analysis showed the excellent linear relationship between the content of hollow coffee carbon polyester and each performance index was obtained. Cubic curve models were built to comprehensively evaluate the performance of the yarn. The blending effect in these yarns was evaluated using the Hamilton transfer index. The tests results show that with the increase of the content of hollow coffee carbon polyester in the blended yarn, the evenness and tensile properties of the hollow coffee carbon polyester/cotton blended yarn continue to increase, whereas the hairiness index and moisture regain of the yarn gradually decrease. With the change of blending ratio, the transfer index of each fiber in hollow coffee carbon polyester/cotton blended yarn will change. When the content of hollow coffee carbon polyester is more than or equal to 50%, it has the tendency to preferentially distribute inward, whereas the cotton fiber has the tendency to preferentially distribute outward. When the content of hollow coffee carbon polyester is less than 50%, the reverse is true. The comprehensive evaluation value of the yarn performance decreased first and then increased with the increase in the content of hollow coffee carbon polyester.

Synthesis and Performance Evaluation of Fuel from Waste Plastics

Plastics are an integral part of our lives and the production of plastics has drastically increased over the years, because of its vast range of applications and usage. Due to this the accumulation of waste plastics has also increased in time. The waste plastic generated in India is 15000 tons per day (as per survey). The breakdown of plastics requires around 500 years in the earth and these waste plastics affect the humans, animals, birds, earth and environment. The demand for conventional fuel has also increased lately and the quantity of this fuel reserve has decreased simultaneously. The extensive usage of the conventional fuels has paved the path for alternative ways for energy sources and alternate fuels. The extraction of waste plastic oil is obtained by the process of pyrolysis which is nothing but the thermochemical decomposition of organic matter without oxygen. The extracted plastic pyrolysis oil is then blended with diesel which helps in reducing the consumption of diesel fuel. Different blend ratios are prepared consisting of the extracted waste plastic pyrolysis oil and diesel fuel. These fuels are tested in the engine to understand the variation in the engine performance and emissions with the help of a gas analyser. By this way, the suitable blend ratio is selected for further works. This blend of fuel can exhibit high thermal efficiency and increases machine efficiency. The fuel does not emit sulphur dioxide (SO2) and the residue obtained is only 5 percent which is said to be carbon.

DEVELOPMENT OF NON-WOVEN FILTER FOR 3 LAYER MASK FROM BAMBOO/POLYPROPYLENE FIBERS

The necessary element of non-public protecting instrumentation is mask. Mask is most necessary in pandemic as a result it safeguard our life by stopping the spreading of the Corona virus by entrapping the droplets from the corona affected person to enter wearer’s nose. There are different typed of mask like non- woven mask, reusable mask, N95 mask and artifact mask etc. Majority of business masks are non-woven masks that are created from polypropylene fiber. The most downside of non-woven masks is its discomfort and affect lack of breathability. This drawback is solved by utilizing natural fibers collectively of the material in non-woven and victimization them in mask. Bamboo fiber may be a natural celluloid fiber having smart comfort properties with antimicrobial properties. Bamboo fiber is also hydroscopic, natural deodorizer and hypoallergenic which provides good breathability and comfort. The polypropylene fiber is used with bamboo to provide good strength and abrasion property. Hence an attempt is made to develop a surgical mask from bamboo fiber with different blend ratios of 70:30, 60:40 and 50:50 of Bamboo and Polypropylene fiber to judge its mechanical properties like GSM and thickness potential as a protecting barrier material in non-woven face masks. The developed non-woven fabric of different blend is compared with each other, and the results shows 50: 50 blend has good mechanical properties, and the results show an effective value of Bacterial Filtration efficiency and Differential Pressure which are the most important parameters to predict the filtration efficiency of a surgical mask.

Recycling of crystalline silicon photovoltaic solar panel waste to modified composite products

This investigation highlights effective technology to convert crystalline silicon photovoltaic solar panel waste to composite products. The main problem with recycling photovoltaic modules is to economically separate and extract the materials in the laminated structure. This investigation was attempted to recycle c-Si photovoltaic modules using an unconventional method in which the cumbersome process of separating the materials in the module is avoided altogether. The aluminium frame, outer glass and junction box are removed mechanically and the rest of the c-Si PV module waste is powdered and blended with recycled polypropylene (PP) and Low Density Polyethylene (LDPE) each to make compression moulded tiles. A total of six compression moulded tiles were made. Three tiles from each base material blended in three blend ratios (0%, 10% and 20%) with the powdered PV module waste. The tensile strengths of the tiles were tested and compared. The results prove that tiles made with recycled PP as a base material show very low tensile strength. However, recycled tiles made by blending with LDPE show appreciable tensile strength of more than 8 MPa. These tiles may be used to make furniture.

A study on comfort properties of oak Tasar silk waste and acrylic blended fabrics

Oak Tasar is wild silk with natural golden brown colour and unique texture available in Himalayan region of India. A lot of fibre waste is generated during hand spinning of oak Tasar silk yarn which can be utilized by blending it with compatible fibre to incorporate the properties of both fibres in the yarn. The present study aimed to develop Oak Tasar silk waste and acrylic blended fabrics and study their comfort properties. The oak Tasar silk and acrylic blended plain weave and twill weave fabrics were prepared with five different blend ratios viz. 100:0, 60:40, 50:50, 40:60 and 0:100. The prepared fabrics were studied for comfort properties like thermal insulation (clo, TIV %), Q-max (warm/cool feeling), air permeability, water vapour transport rate and were statistically analysed. Results revealed that thermal insulation and clo value were found to be increased with increasing acrylic content in the fabric whereas Q- max, air permeability, water vapour permeability values were reduced with the addition of oak Tasar silk fiber in the blend. The 50:50 blended plain weave fabric among the blended fabrics had the highest clo value, i.e. 0.52 and 50:50 blended twill weave fabric had highest Q max value i.e. 0.109W/cm2. It was found from the study that the developed fabrics are comfortable and can be used for light winters.

Investigating the electrical percolation threshold of ternary composite films with different compatibility between polymer blends

Electrical conductive of polystyrene (PS)/poly(butyl methacrylate) (PBMA)/carbon black (CB) and PS/poly (cyclohexyl methacrylate) (PChMA)/CB ternary composite films with different polymer blend ratios are prepared through solution casting. The percolation thresholds (ϕ c ) of all the composite films before and after thermal annealing have been determined through the McLachlan GEM equation. Moreover, the PS/poly (methyl methacrylate) (PMMA)/CB and PS/poly (ethyl methacrylate) (PEMA)/CB films obtained from the same method while only considering conductivity after thermal annealing as well in this work for comparison. Though the CB particles are revealed to be located at only one polymer phase of all four different polymer blends, with compatibility between polymer blends increasing, the ternary composite films show different ϕ c behaviors by changing polymer blend ratios. In PS/PChMA/CB case, the phase separation between PChMA and PS cannot be observed under scanning electron microscope (SEM). After thermal annealing, all the ϕ c of PS/PChMA/CB films with different PS/PChMA ratios almost show a linear behavior instead of the double percolation behavior with PChMA content increasing. Suppose both ϕ c of binary systems (polymer A/filler and polymer B/filler) is determined. In that case, a linear behavior relationship between the ϕ c of the ternary composites (A + B + fillers) with the ratio of two polymers can be revealed when polymer A and B are miscible.