... Characterization of FP-MA Palmitic acid is a renewable resource which is derived from palmoil... more ... Characterization of FP-MA Palmitic acid is a renewable resource which is derived from palmoil. ... In-situ polymerization of FP-MA took place during the fabrication of the composites and the ... shown in Figure 7. Flexural properties of the 70% (w/w) jute fiber reinforced biocomposite ...
ABSTRACT A series of sulfonated poly(ether imide)–silica hybrid membranes (SPI/S-X) were prepared... more ABSTRACT A series of sulfonated poly(ether imide)–silica hybrid membranes (SPI/S-X) were prepared from fluorine-containing ter-copolyimide and ~15 nm colloidal silica particles. The soluble poly(ether imide) with carboxylic acid pendant groups was synthesized by one pot high temperature polycondensation reaction using a sulfonated diamine, 4,4′-diaminostilbene-2,2′-disulfonic acid (DSDSA), fluorinated quadri diamine (QA), 3,5-diaminobenzoic acid (DABA) and 1,4,5,8-naphthalenetetracarboxylic dianhydride (NTDA). Such pendant carboxylic acid groups undergo condensation reaction with colloidal silica to provide organic–inorganic bonding that effectively improves the compatibility of nanocomposite membranes. Structure of the synthesized polymer was analysed by FT-IR and 1H NMR spectroscopy. The esterification reaction was carried out between colloidal silica particles (with different loading) and the carboxylic acid containing polymer chains by thermal treatment in presence of p-toluenesulfonic acid (PTSA), which catalysed the esterification reaction. The prepared hybrid membranes exhibited excellent thermal and oxidative stability. Mechanical properties of the membranes were enhanced with certain wt. % of silica loading whereas the swelling ratio and oxygen permeability of the membranes was reduced by cross-linking. The microstructure of the resulting hybrid membranes were extensively investigated by SEM and TEM. Good compatibility and uniform distribution of the silica nanoparticles in the hybrid membrane was observed by SEM. Excellent nano-phase separated structure was observed under TEM which indicated the formation of well-dispersed hydrophilic domains throughout the membrane. The hybrid membranes showed significantly high proton conductivity in water medium which is in the range of commercially available Nafion® membrane under similar experimental condition.
ABSTRACT Three new co-poly(arylene ether)s (PAE) containing cardo fluorene moiety in the main cha... more ABSTRACT Three new co-poly(arylene ether)s (PAE) containing cardo fluorene moiety in the main chain and pendent trifluoromethyl group have been synthesized by one pot high temperature polycondensation reaction using two kinds of bis-hydroxy compound, 9,9-bis(3,5-dimethoxy-4-hydroxyphenyl)fluorene (DMHF), bisphenol A (BPA) and three different bis-fluoro monomers. The structures of the resulting co-PAEs were investigated by FT-IR and NMR spectroscopy. All the polymers showed good solubility in common organic solvents and high weight average molecular weight up to 443,000 g/mol. Flexible, transparent and mechanically strong films were obtained after solution casting from N,N-dimethylacetamide (DMAc). The polymers exhibited reasonably high thermal stability (Td10, in the range of 459–485 °C) and high glass transition temperature (215–228 °C). The PAE membranes also revealed good optical transparency (λcut-off = 350–370 nm) along with very small water absorption (0.38–0.49%) after 72 h immersion in water. Furthermore, the PAE membranes showed low dielectric constants with the values in the range of 2.25–2.42 at room temperature and at 1 MHz frequency, measured from their capacitance.
ABSTRACT Abstract: Most polymers, at present, are petroleum-based and do not degrade over many de... more ABSTRACT Abstract: Most polymers, at present, are petroleum-based and do not degrade over many decades under normal environmental conditions. As a result, efforts toward developing environmental-friendly and biodegradable “green” polymers for various commercial applications have gained signifi cant momentum in recent years. The current interest in the development of useful biodegradable polymeric materials has encouraged scientists and industrialists to use readily available renewable, inexpensive raw materials such as carbohydrates, lignin, starch, gums, chitosan, vegetable oils, and fatty acids. Vegetable oils, which are triglycerides of fatty acids, specially, the nonedible grade, are being investigated by the researchers extensively as a suitable alternative to petroleum oil. Fatty acids, when converted into polymers, give new materials with useful properties such as fl exibility, hydrophobicity, and pliability. At the same time, degradation into naturally occurring compounds makes them highly environmental-friendly. Besides their renewable, environmental-friendly, and inexpensive nature, they are useful for various applications like wound dressing materials, drug delivery and implantable devices, in surface-coating industries, as high-damping structural material, etc. Fatty acid monomers are integrated into the polymeric chains by using various techniques. Most fatty acids are monofunctional in nature and act only as chain terminator during polymerization. This limitation has been overcome by dimerization of unsaturated fatty acids or by creating a functional group on the monomers. In future, such green materials may offer many new exciting applications. Development in the genetic sciences will have a great impact on the materials science area of fatty acid–based materials. Better characterization and fundamental studies on fatty acid–based polymers and composites will create new applications which could lead to replacement of many available synthetic polymers and other materials. They also comply with the emerging concept of sustainable development. In this chapter, the recent trends in converting fatty acids into green polymers and green composite materials have been summarized, while also providing insights to future trends.
... Characterization of FP-MA Palmitic acid is a renewable resource which is derived from palmoil... more ... Characterization of FP-MA Palmitic acid is a renewable resource which is derived from palmoil. ... In-situ polymerization of FP-MA took place during the fabrication of the composites and the ... shown in Figure 7. Flexural properties of the 70% (w/w) jute fiber reinforced biocomposite ...
ABSTRACT This article reports the synthesis and characterization of several new fluorinated sulfo... more ABSTRACT This article reports the synthesis and characterization of several new fluorinated sulfonated poly(arylene ether sulfone) (6FBPAQSH-XX). The structures of the prepared copolymers were confirmed by FTIR and NMR spectroscopy. The copolymers showed high molecular weight, good solubility, and film-forming capabilities. The copolymers exhibited high thermal and oxidative stability and good mechanical properties depending upon their chemical compositions. Transmission electron microscopy (TEM) showed cluster like microstructures for the copolymer membranes suggesting good phase separated morphology. The cluster size increased with increasing mole percentage of sulfonate comonomer and was in the range of 5–65 nm. The copolymers showed good dimensional stability with very low water uptake and swelling ratios. Ion exchange capacity (IECW) of the copolymer films was determined by titration methods and was also calculated from the monomer composition obtained by 1H NMR spectroscopy. The proton conductivities of acid form membrane increased with IECW value and temperature, with maximum to 108 mS/cm at 90 °C for 6FBPAQSH-60 copolymer.
... Characterization of FP-MA Palmitic acid is a renewable resource which is derived from palmoil... more ... Characterization of FP-MA Palmitic acid is a renewable resource which is derived from palmoil. ... In-situ polymerization of FP-MA took place during the fabrication of the composites and the ... shown in Figure 7. Flexural properties of the 70% (w/w) jute fiber reinforced biocomposite ...
ABSTRACT A series of sulfonated poly(ether imide)–silica hybrid membranes (SPI/S-X) were prepared... more ABSTRACT A series of sulfonated poly(ether imide)–silica hybrid membranes (SPI/S-X) were prepared from fluorine-containing ter-copolyimide and ~15 nm colloidal silica particles. The soluble poly(ether imide) with carboxylic acid pendant groups was synthesized by one pot high temperature polycondensation reaction using a sulfonated diamine, 4,4′-diaminostilbene-2,2′-disulfonic acid (DSDSA), fluorinated quadri diamine (QA), 3,5-diaminobenzoic acid (DABA) and 1,4,5,8-naphthalenetetracarboxylic dianhydride (NTDA). Such pendant carboxylic acid groups undergo condensation reaction with colloidal silica to provide organic–inorganic bonding that effectively improves the compatibility of nanocomposite membranes. Structure of the synthesized polymer was analysed by FT-IR and 1H NMR spectroscopy. The esterification reaction was carried out between colloidal silica particles (with different loading) and the carboxylic acid containing polymer chains by thermal treatment in presence of p-toluenesulfonic acid (PTSA), which catalysed the esterification reaction. The prepared hybrid membranes exhibited excellent thermal and oxidative stability. Mechanical properties of the membranes were enhanced with certain wt. % of silica loading whereas the swelling ratio and oxygen permeability of the membranes was reduced by cross-linking. The microstructure of the resulting hybrid membranes were extensively investigated by SEM and TEM. Good compatibility and uniform distribution of the silica nanoparticles in the hybrid membrane was observed by SEM. Excellent nano-phase separated structure was observed under TEM which indicated the formation of well-dispersed hydrophilic domains throughout the membrane. The hybrid membranes showed significantly high proton conductivity in water medium which is in the range of commercially available Nafion® membrane under similar experimental condition.
ABSTRACT Three new co-poly(arylene ether)s (PAE) containing cardo fluorene moiety in the main cha... more ABSTRACT Three new co-poly(arylene ether)s (PAE) containing cardo fluorene moiety in the main chain and pendent trifluoromethyl group have been synthesized by one pot high temperature polycondensation reaction using two kinds of bis-hydroxy compound, 9,9-bis(3,5-dimethoxy-4-hydroxyphenyl)fluorene (DMHF), bisphenol A (BPA) and three different bis-fluoro monomers. The structures of the resulting co-PAEs were investigated by FT-IR and NMR spectroscopy. All the polymers showed good solubility in common organic solvents and high weight average molecular weight up to 443,000 g/mol. Flexible, transparent and mechanically strong films were obtained after solution casting from N,N-dimethylacetamide (DMAc). The polymers exhibited reasonably high thermal stability (Td10, in the range of 459–485 °C) and high glass transition temperature (215–228 °C). The PAE membranes also revealed good optical transparency (λcut-off = 350–370 nm) along with very small water absorption (0.38–0.49%) after 72 h immersion in water. Furthermore, the PAE membranes showed low dielectric constants with the values in the range of 2.25–2.42 at room temperature and at 1 MHz frequency, measured from their capacitance.
ABSTRACT Abstract: Most polymers, at present, are petroleum-based and do not degrade over many de... more ABSTRACT Abstract: Most polymers, at present, are petroleum-based and do not degrade over many decades under normal environmental conditions. As a result, efforts toward developing environmental-friendly and biodegradable “green” polymers for various commercial applications have gained signifi cant momentum in recent years. The current interest in the development of useful biodegradable polymeric materials has encouraged scientists and industrialists to use readily available renewable, inexpensive raw materials such as carbohydrates, lignin, starch, gums, chitosan, vegetable oils, and fatty acids. Vegetable oils, which are triglycerides of fatty acids, specially, the nonedible grade, are being investigated by the researchers extensively as a suitable alternative to petroleum oil. Fatty acids, when converted into polymers, give new materials with useful properties such as fl exibility, hydrophobicity, and pliability. At the same time, degradation into naturally occurring compounds makes them highly environmental-friendly. Besides their renewable, environmental-friendly, and inexpensive nature, they are useful for various applications like wound dressing materials, drug delivery and implantable devices, in surface-coating industries, as high-damping structural material, etc. Fatty acid monomers are integrated into the polymeric chains by using various techniques. Most fatty acids are monofunctional in nature and act only as chain terminator during polymerization. This limitation has been overcome by dimerization of unsaturated fatty acids or by creating a functional group on the monomers. In future, such green materials may offer many new exciting applications. Development in the genetic sciences will have a great impact on the materials science area of fatty acid–based materials. Better characterization and fundamental studies on fatty acid–based polymers and composites will create new applications which could lead to replacement of many available synthetic polymers and other materials. They also comply with the emerging concept of sustainable development. In this chapter, the recent trends in converting fatty acids into green polymers and green composite materials have been summarized, while also providing insights to future trends.
... Characterization of FP-MA Palmitic acid is a renewable resource which is derived from palmoil... more ... Characterization of FP-MA Palmitic acid is a renewable resource which is derived from palmoil. ... In-situ polymerization of FP-MA took place during the fabrication of the composites and the ... shown in Figure 7. Flexural properties of the 70% (w/w) jute fiber reinforced biocomposite ...
ABSTRACT This article reports the synthesis and characterization of several new fluorinated sulfo... more ABSTRACT This article reports the synthesis and characterization of several new fluorinated sulfonated poly(arylene ether sulfone) (6FBPAQSH-XX). The structures of the prepared copolymers were confirmed by FTIR and NMR spectroscopy. The copolymers showed high molecular weight, good solubility, and film-forming capabilities. The copolymers exhibited high thermal and oxidative stability and good mechanical properties depending upon their chemical compositions. Transmission electron microscopy (TEM) showed cluster like microstructures for the copolymer membranes suggesting good phase separated morphology. The cluster size increased with increasing mole percentage of sulfonate comonomer and was in the range of 5–65 nm. The copolymers showed good dimensional stability with very low water uptake and swelling ratios. Ion exchange capacity (IECW) of the copolymer films was determined by titration methods and was also calculated from the monomer composition obtained by 1H NMR spectroscopy. The proton conductivities of acid form membrane increased with IECW value and temperature, with maximum to 108 mS/cm at 90 °C for 6FBPAQSH-60 copolymer.
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