http://localhost:8081/jspui/handle/123456789/15069 Thu, 07 May 2026 20:49:54 GMT 2026-05-07T20:49:54Z http://localhost:8081/jspui/handle/123456789/20542 Title: WASTE DETECTION AND ITS CLASSIFICATION USING MACHINE/DEEP LEARNING MODEL Authors: S, Sarvana Kumar Sat, 01 Jun 2024 00:00:00 GMT http://localhost:8081/jspui/handle/123456789/20542 2024-06-01T00:00:00Z http://localhost:8081/jspui/handle/123456789/20457 Title: NATURAL FIBER REINFORCED FUNCTIONALIZED STYRENIC POLYMER COMPOSITE Authors: Verma, Harsha Abstract: Renewable, eco-friendly, biodegradable, and sustainable natural fibers offer good properties and are replacing synthetic and inorganic fibers, as reinforcements for polymer composites. Eco-friendly natural fiber reinforced polymer composites have good properties and therefore offer several commercial and industrial applications and support agro-based economy. Due to the presence of hydroxyl groups in their constituents, natural fibers are polar and hydrophilic and polymers are non-polar and hydrophobic, and this creates a poor interfacial adhesion between them and that limits the mechanical properties of a natural fiber/polymer composite. Following three processes are used to improve the fiber/matrix interfacial adhesion in natural fiber/polymer composites: (i) Fiber treatment process (ii) Compatibilizer process (iii) Palsule process. Their combinations are also used: (iv) Combined Fiber Treatment and Compatibilizer Process (v) Combined Fiber Treatment and Palsule process. Matrix polymers for the composites by Palsule process have been functionalized by maleic anhydride (MA) and by glycidyl-methacrylate (GMA). The MA functional groups of the polymer react with the –OH groups of the reinforcing natural fiber and develop adhesion between them in the composites by Palsule process by developing ester and hydrogen bonds. In the case of GMA functionalized matrix, the GMA functional groups of the polymer react with the –OH groups of the reinforcing natural fiber and develop interfacial adhesion in the composites by developing ether bonds and hydrogen bonds. Natural fiber reinforced composites have been developed by the Palsule process that are based on a MA functionalized graft or block copolymer as the matrix, which has a relatively small content (up to 10%) of the MA functional group and the composites have been processed up to 150oC, except the two composites that have been processed at relatively higher temperatures, around 190oC, retaining the stability of thermally sensitive natural fibers. This study extends the Palsule process to natural fiber reinforced MA chemically functionalized polymer composites, based on a MA functionalized matrix polymer requiring processing at higher temperatures, (relative to the reported composites by Palsule process) retaining the thermal stability of the thermally sensitive natural fibers, and also evaluates their recycling. Accordingly, this study, selects a newer polymer, that is functionalized, not as graft nor as block co polymer, but as a random copolymer, and also contains higher amounts (18%) of functional groups. Given the success of the styrenic CF-SEBS, CF-ABS and CF-SAN matrix composites by the Palsule process, this study evaluates a styrenic polymer as the matrix, a polystyrene polymer functionalized with 18% maleic anhydride (MA), a chemically functionalized polystyrene (CF-PS), as the matrix, that requires relatively higher processing temperature (up to 210℃). This study selects two original untreated natural fibers as reinforcement, Bagasse fibers (BGSEF) and Sisal fibers (SLF), as reinforcements. Thus, this study develops two composites, BGSEF/CF-PS composites and SLF/CF PS composites, evaluates their structure and properties, and also recycles them, to examine the reinforcement / matrix adhesion in the recycled composites and recycling effects on the properties of the recycled composites. The BGSEF/CF-PS and SLF/CF-PS Composites were processed with twin screw extrusion and injection moulding to obtain their ASTM standard specimens. Both, the BGSEF/CF-PS and SLF/CF PS composites showed higher tensile and flexural properties, but lower unnotched Izod impact strength than their respective matrix. The SEM micrographs show reinforcement embedded and covered with matrix, with a possibility of reinforcing fibre breakage, but no fibre pull out and no voids. FTIR spectroscopy of the composites, establishes this good fiber/matrix adhesion in the BGSEF/CF-PS composites and SLF/CF-PS composites, as resulting from the esterification reaction and the hydrogen bonding between the hydroxyl groups of the natural fibers and the maleic anhydride group of the chemically functionalized CF-PS polymer matrix, as per the Palsule process. Both the composites, the BGSEF/CF-PS composites and SLF/CF-PS composites have thermal stability in-between their respective reinforcing natural fiber and the matrix and are thermally stable at-least upto 290oC. The water absorption percentage and thickness swelling of the BGSEF/CF-PS composites and SLF/CF-PS composites increased with the increase in the amount of reinforcement in them. The water absorbed wet composites show lower tensile and flexural properties with reference to the dry composites, but higher than that of the dry CF-PS matrix. The BGSEF/CF-PS and the SLF/CF-PS composites have several potential applications in commodity, commercial and also light engineering systems. The R-(BGSEF/CF-PS) and R-(SLF/CF-PS) Composites have been obtained by the first recycling of the original BGSEF/CF-PS and the original SLF/CF-PS composites respectively and processed with twin screw extrusion followed by their injection molding for their ASTM standard samples. Both the composites, (R-(BGSEF/CF-PS) and R-(SLF/CF-PS), show higher tensile and flexural properties, but lower unnotched Izod impact strength relative to the recycled matrix. The SEM micrographs show that the reinforcement has remained embedded in and covered with matrix, even after recycling, establishing the retention of good adhesion between the matrix and the reinforcement in the recycled composites, and the FTIR spectroscopy establishes this retention due to the esterification reaction and the hydrogen bonding between the hydroxyl groups of the reinforcement and the matrix, (as in the original composites), as per the Palsule process. Both the composites, the R-(BGSEF/CF-PS) and R-(SLF/CF-PS) composites are thermally stable at-least upto 269oC. The R (BGSEF/CF-PS) composites and the R-(SLF/CF-PS) composites have the potential to replace the respective original composites (with lower reinforcement (BGSEF/SLF) contents and similar properties) for the respective commodity, commercial and also light engineering systems. Of all the composites (the two original and the two recycled composites), the highest tensile strength and tensile modulus, is exhibited by the 30/70 SLF/CF-PS composite, however, the lowest tensile elongation at break is exhibited by the 30/70 R-(BGSEF/CF-PS) composite and the highest flexural modulus and strength is exhibited by the 30/70 SLF/CF-PS composite. The highest unnotched Izod impact strength is demonstrated by the 30/70 BGSEF/CF-PS composite. The 30/70 SLF/CF-PS composite shows the highest thermal stability up to a temperature of approx. 305°C. Wed, 01 May 2024 00:00:00 GMT http://localhost:8081/jspui/handle/123456789/20457 2024-05-01T00:00:00Z http://localhost:8081/jspui/handle/123456789/20449 Title: NATURAL FIBER REINFORCED FUNCTIONALIZED STYRENE ACRYLONITRILE COMPOSITES Authors: Tamta, Nisha Abstract: Recent work is directed towards significant advancements in the applications of renewable, eco friendly, biodegradable, and sustainable natural fibers as reinforcements for polymer composites. Due to their excellent properties, these natural fibers are replacing synthetic and inorganic fibers as reinforcements for several polymer composites. Natural fibers reinforced polymer composites have many commodity, commercial, and engineering applications, and these composites promote agro-based agricultural economy and support farmers cultivating these natural fibers. However, the inherent polarity and hydrophilicity of natural fibers, due to the presence of hydroxyl groups in their ligno-cellulosics, in contrast with the non-polar and hydrophobic nature of polymers results in their poor interfacial adhesion, limiting the mechanical performance of these natural fiber/polymer composites. Following three processes and their combinations have been developed to enhance the fiber/matrix interfacial adhesion in natural fiber/polymer composites, as follows: (i) Fiber Treatment Process, for the reinforcement (ii) Compatibilizer Process to improve the reinforcement/matrix interface and (iii) Palsule process, wherein the used matrix is a functionalized polymer. Their combinations are also being used: (iv) Combined Fiber Treatment and Compatibilizer Process, and (v) Combined Fiber Treatment and Palsule Process. In Palsule process, the functional groups of a chemically functionalized polymer matrix react with functional groups of lingo-cellulosic of a natural fiber and impart improved interfacial adhesion between the reinforcing natural fiber and the functionalized polymer matrix. The process does not need any fiber treatment and also does not need any compatibilizer, for processing the natural fiber/polymer composite. Composites based on following functionalized polymers have been reported by Palsule process: functionalized polyolefin (CF-PE and CF-PP) based composites; functionalized thermoplastic elastomer (CF-EPR and CF-SEBS) based composites: functionalized thermoplastic (CF-ABS) based composites. All these composites are based on matrix polymers functionalized by maleic anhydride (MA). In these composites, fiber/matrix adhesion results from esterification and hydrogen bonding between them. Palsule process has been extended to composites based on matrix polymers functionalized by glycidyl methacrylate (GMA) and GMA functionalized CF-VLDPE and CF- EBA composites have been reported. In these composites, fiber/matrix adhesion results from etherification and hydrogen bonding between them. iii Reported natural fiber-reinforced composites developed by the Palsule process are based on polymer matrix functionalized by grafting, but containing a relatively low concentration (up to 3%) of the MA / GMA functional groups. These composites have been processed at temperatures up to 150°C, with the exception of CF-ABS composites processed at higher temperatures around 190°C, while still maintaining the stability of thermally sensitive natural fibers. This study extends Palsule process to a matrix polymer, functionalized by a method, other than grafting, and having higher (approx. 10%) functionality; and requiring higher (195oC) processing temperature and processing by extrusion at more than 350 rpm of the twin screws of the extruder. In view of success of styrenic polymers based natural fibers reinforced composites by Palsule process; this study selects a styrenic polymer, a chemically functionalized styrene-acrylonitrile polymer (CF-SAN), as the matrix. This CF-SAN is a random ter-polymer (not graft) with higher functionality (approx. 10%), and requires processing at a temperature of 195oC. This study selects two reinforcing natural fibers, untreated kenaf fibers (KNF) fibers and untreated hemp fibers (HMPF) that have approx. 10% difference between their holo-cellulose and also lignin contents. This study develops two composites: KNF/CF-SAN composites and HMPF/CF-SAN composites and evaluates their structure and properties. This study also performs only one, the first recycling of these composites, to assess the impact of recycling on the reinforcement/matrix adhesion in the recycled composites, and its effects on the properties of the composites. Following properties of the composites are evaluated: Mechanical: tensile, flexural and impact properties; dynamic mechanical thermal: tan-, storage modulus and loss modulus properties and thermal properties: initiation of degradation temperature, temperature at the maximum rate of degradation and residual mass at 800oC. The KNF/CF-SAN and HMPF/CF-SAN composites have been processed by twin-screw extruder, operated at more than 350 rpm, and their ASTM standard samples have been processed by injection molding process. FE-SEM micrographs reveal reinforcing fibers embedded in and coated with the matrix, with potential fiber breakage observed, though no fiber pull-out or voids were detected. ATR-IR spectroscopy confirmed fiber/matrix adhesion in both composites, attributed to the esterification reaction and hydrogen bonding between the hydroxyl groups of the natural fibers and the maleic anhydride groups in the chemically functionalized CF-SAN iv polymer matrix, in accordance with the Palsule process. Tensile and flexural modulus and strengths, and unnotched Izod impact strength of both, KNF/CF-SAN and HMPF/CF-SAN, composites are higher than that of their respective CF-SAN matrix and increase with the increasing amounts of reinforcing KNF and HMPF, in the composites; however, their tensile elongation at break is lower than that of their respective CF-SAN matrix and decreases with increasing amounts of reinforcing fibers, KNF and HMPF in them. The measured tensile strength and tensile modulus values of KNF/CF-SAN and HMPF/CF-SAN composites developed in this study have been compared with the values predicted by various equations. Dynamic mechanical thermal properties (storage modulus and loss modulus) of both, KNF/CF-SAN and HMPF/CF SAN, composites are higher than that of their respective CF-SAN matrix and increase with the increasing amounts of reinforcing KNF and HMPF, in the composites. Thermal analysis indicates that the thermal stability of both, KNF/CF-SAN and HMPF/CF-SAN, composites is intermediate between that of the reinforcing KNF and HMPF and the CF-SAN matrix. Both composites, KNF/CF-SAN and HMPF/CF-SAN, are environmentally friendly and provide both technological and economic benefits. They also offer various potential applications. Thu, 01 Aug 2024 00:00:00 GMT http://localhost:8081/jspui/handle/123456789/20449 2024-08-01T00:00:00Z http://localhost:8081/jspui/handle/123456789/20426 Title: FIRE RETARDANCY BEHAVIOUR OF COTTON FABRIC COATED WITH BIO AND SYNTHETIC MATERIALS Authors: Vishwakarma, Ajay Abstract: Every year, fire accidents are responsible for killing larger number of people compared to any other natural disasters. The demand for development of new and efficient fire retardant materials is continuously increasing due to increment in fire accidents that causing property damage and loss of human lives. During fire-related accidents, the usage of effective fire-retardant materials could give individuals enough time to flee from the flames, reducing the number of injuries and reduce damage to the properties. The fire retardant materials in the market are offered in variety of forms, e.g., coatings, textiles, composites, etc. These fire retardant materials could be utilized in designing of various fire proof products like upholstery, seat covers, building walls, apartment partitions, and the bodies of automotive (trains and airplanes). These fire retardant products are prepared using different fire retardant materials and with varying compositions. The halogen based fire retardant materials are commonly used fire retardant materials in the past decade due to their high effectiveness and ability to reduce the fire spread but they release toxic gases during their burning, which cause environmental pollution and harmful effects on humans. So, at present, inorganic, nitrogen, and phosphorous-based compounds are replacing halogen based fire retardant materials because of their environmental friendly nature and low harmful effects on humans. Among all environment friendly or lower toxic fire retardant materials, some materials could be obtained from nature (biopolymers) that can demonstrate superior fire retardancy and release less smoke. Mon, 01 Apr 2024 00:00:00 GMT http://localhost:8081/jspui/handle/123456789/20426 2024-04-01T00:00:00Z