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The present work deals with the graft copolymerization of ethyl acrylate (EA) onto lignocellulosic natural fibers of the Himalayan region in air in the presence of potassium persulfate (KPS) as initiator. Raw fibers and the graft copolymers after the completion of copolymerization reaction were subjected to evaluation of different properties. Correlation of physicochemical properties with the graft copolymerization reaction mechanism is discussed. Characterization of the graft copolymers was carried out with scanning electron microscopy, Fourier transform-infrared spectrophotometry, and thermogravimetric analysis.

Natural cellulosic fibers are one of the smartest materials for use as reinforcement in polymers possessing a number of applications. Keeping in mind the immense advantages of the natural fibers, in present work synthesis of natural cellulosic fibers reinforced polymer composites through compression molding technique have been reported. Scanning Electron microscopy (SEM), Thermo gravimetric/Differential thermal/Derivative Thermogravimetry (TGA/DTA/DTG), absorption in different solvents, moisture absorbance, water uptake and chemical resistance measurements were used as characterization techniques for evaluating the different behaviour of cellulosic natural fibers reinforced polymer composites. Effect of fiber loading on mechanical properties like tensile strength, flexural strength, compressive strength and wear resistances has also been determined. Reinforcing of the polymer matrix with natural fibers was done in the form of short fiber. Present work indicates that green composites can be successfully fabricated with useful mechanical properties. These composites may be used in secondary structural applications in automotive, housing etc.

Graft copolymerization of cellulosic biopolymers with synthetic polymers is of enormous interest because of its application in biofiltration, biosorption, biomedical, biocomposites and various other eco-friendly materials. Synthesis of graft copolymers of methyl acrylate onto mercerized Grewia optiva biofibers using ferrous ammonium sulfate–potassium per sulfate as redox initiator in air was carried out. Different reaction parameters such as amount of solvent, monomer concentration, initiator molar ratio, reaction time and reaction temperature were optimized to get the maximum percentage of grafting. The graft copolymers thus formed were characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, thermogravimetric analysis, differential thermal analysis and differential thermogravimetric techniques. A plausible mechanism for explanation of the graft copolymerization reactions pattern shown is offered. The effect of grafting percentage on the physico–chemical properties of raw as well as grafted Grewia optiva biofibers has also been investigated. The graft copolymers have been found to be more moisture resistant and also showed better chemical and thermal resistance. Green polymer composites were also successfully prepared through compression molding technique by using grafted Grewia optiva biofibers as reinforcement.

The 21st century offers vast challenges for researchers all around the globe, especially regarding the effective use of sustainable polymers and their materials for different applications. With this focus, sustainable polymers are now rising as one of the most feasible alternatives to traditional synthetic polymers/materials for a variety of indust

During the last few decades, synthetic polymers have emerged as new potential viable alternative to traditional metallic and ceramic materials due to their inherent properties such as flexibility, light weight, corrosion resistance, and easy processing. However, these synthetic polymers also pose some serious threats to our environments due to the toxic and hazardous chemicals associated during their synthesis and afterward their end use applications. Although these synthetic polymers have benefited the human being to a great extent, recently efforts are being made to reduce their use. The prime reason for this is the increasing environmental awareness and health concerns. All these concerns have led to intensive research on natural polymer-based materials derived from different biorenewable resources. Among bio-based polymers, cellulose fibers offer a very high potential as biodegradable biorenewable material. However, the presence of hydrophilic groups on natural cellulosic fibers limits their applications in everyday use. In order to overcome the disadvantages associated with these fibers, graft copolymerization is the most trusted tool to alter their properties for targeted applications. So in the present book chapter we report some of our studies on the chemical functionalization of natural cellulosic fibers through free radical-induced graft copolymerization technique.

In the present study, free radical induced graft-copolymerization of natural cellulosic polymers (Grewia optiva) has been carried out to develop the novel materials meant for green composites and many other applications. During the graft copolymer synthesis diverse reaction parameters that significantly affect the percentage of grafting were optimized. The structural, thermal and physico-chemical changes in the natural cellulosic polymers based graft copolymers have been ascertained with scanning electron micrography, Fourier transform infrared spectroscopy, thermogravimetric analysis (TGA) and swelling studies. The swelling studies of the grafted cellulosic polymers have been carried out in different solvents to assess the possible applicability of these natural polymers. Green composites were also prepared using raw/grafted cellulosic polymers. It has been found that grafted polymers (Grewia optiva) based green composites gives better tensile properties than the parent natural cellulosic polymers based composites.

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.

Cellulose, a linear polysaccharide polymer with numerous glucose monosaccharide units is of enormous interest because of its applications in biosorption, biomedical, packaging, biofiltration and biocomposites. In this study, cellulose-graft-poly(butyl acrylate) copolymers were synthesized under microwave conditions. Effects of microwave radiation doses and different reaction parameters were optimized to get the optimum percentage of grafting. The dependence of optimum conditions for better physico-chemical properties of the cellulosic polymers was also determined. Fourier transform infrared spectroscopy (FT-IR) analysis was used to authenticate the chemical reaction taking place between cellulosic polymers and monomer. The thermogravimetric behavior of the raw and grafted cellulosic polymers was characterized by thermogravimetric analysis (TGA). The surface structure of the raw and grafted cellulosic polymers was analyzed through scanning electron microscopy (SEM). The graft copolymers have been found to be more moisture resistant and also showed better chemical and thermal resistance.

Cellulose-based materials are one of the most significant candidates for the preparation of a number of copolymers by graft copolymerization owing to their linear structure, providing good reinforcing properties to the resulting copolymers. Therefore, in the present study, in an effort to develop novel low-cost ecofriendly green polymeric materials, graft copolymers based on lignocellulose were synthesized by graft copolymerization of methyl methacrylate. Different reaction parameters were optimized to get the optimum graft yield, and the graft copolymers were subjected to the analysis of different physicochemical properties. © 2012 Wiley Periodicals, Inc. Adv Polym Techn 32: E741–E748, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/adv.21317

In the present work, graft copolymerization of ethyl acrylate (EA) onto mercerized natural cellulosic polymers in air in the presence of potassium persulfate (KPS) as initiator to impart low water absorbency is reported. Synthesized cellulose graft copolymers were characterized with FT-IR spectrophotometry, scanning electron microscopy (SEM), and thermal analysis TGA/DTA techniques. Thermal stability of natural polymer-g-poly (EA) was found to be more than that of raw and mercerized cellulosic polymers. On grafting, the graft copolymers were also found to exhibit more moisture, chemical, and thermal resistance.

The increasing demand for green, environmentally friendly materials has resulted in new natural fiber–based materials as replacements for nondegradable materials derived from petroleum resources that are currently being used for a number of applications. Hence, this study deals with long fiber–reinforced green polymer composites fabricated using the compression molding technique. Initially, green composites were produced with long fibers using 10, 20, 30, and 40 wt.% fiber loading. A fiber content of 30 wt.% was found to exhibit optimum mechanical properties. Physicochemical properties of the composites were also tested to check their application potential in everyday life.

Cellulose-graft-poly (methylacrylate) copolymers were prepared by microwave assisted free radical polymerization to develop an efficient rapid way to alter the surface properties of the cellulosic fibers. The effect of microwave radiation doses, ratio of monomer, solvent and initiator concentrations were determined to get the highest percentage of grafting. The graft copolymers were characterized by FTIR and SEM studies. The results clearly demonstrate that graft polymerization successfully occurred onto the cellulose backbone. The cellulose-graft-poly (methylacrylate) copolymers have been found to be more water- and moisture-resistant as well as also revealing enhanced chemical and thermal resistance.

Scientific research has been invigorated by a new class of biodegradable materials as alternatives to polymers derived from fossils. Such biomaterials can also offer economic advantages because they are derived from renewable resources. Several biopolymers (gelatin, chitin, chitosan, starch, pectin, cellulose and its modified versions, etc.) have been exploited to produce films and formulations. Their use is limited because of fast degradation, predominant hydrophilic character, and, in some cases, unsatisfactory mechanical properties. However, the properties of these polymers can be improved by using inorganic fillers such as additives. Halloysite nanotube is a promising green filler for this purpose.