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The present article reports an energy efficient method for the synthesis of superparamagnetic ferrite (Fe 3 O 4 ) nanoparticles (10–40 nm) and their annealing effect on the morphology, size, curie temperature and magnetic behavior at 50, 300, 400 and 500 °C. The synthesized nanoparticles were characterized by various spectroscopic techniques like FT-IR and UV–visible. The crystalline structure and particle size were estimated through solid phase as well as the liquid phase using XRD, TEM and DLS techniques. Superparamagnetic behavior of nanoparticles was confirmed by VSM. The EPR study reveals that the main feature of X-Band solid state EPR spectrum has strong transition at g eff ∼ 3.23 (2100G) and a relatively weak transition at g eff ∼ 2.05 (3300G). The later transition further confirms the super paramagnetic nature of these nano ferrites. The activation energy and order of weight losses of nano ferrites were found to be: 39.6 KJ mol −1 and 0.21 orders (600–800 °C), respectively, analyze with the help of TGA while the specific surface area (23.1 m 2 g −1 ) and pore size (9 A) were determined by Quanta chrome BET instrument.

Research efforts are being focused to develop polymers from bioresources such as plant oils from ecological and economical viewpoints, both in academic research and chemical industry worldwide. Plant oil polymers, their organic–inorganic hybrids and composites find versatile applications today. In the present work, we have reported the preparation and characterization of linseed oil based poly (ester urethane) metallohybrids [PEUMH] from linseed oil polyol [LPO], phthalic anhydride [PAN], toluylene-2,4-diisocyanate [TDI] as organic and copper (II) acetate [Cu-Ac] (in different amount) as inorganic precursors, respectively, in “one-pot, multi-step” reaction. PEUMH were characterized by spectral, physico-chemical, thermal (TGA and DSC) and morphological analyses by standard methods. The potentiality of the same as promising coating material was also evaluated. PEUMH are foreseen as prospective candidates for application as antibacterial self-sterilizing protective coatings due to oligodynamic effect of metal.

Recently, biohybrid materials have gained considerable interests worldwide. They consist of bioresource based derivative as organic matrix in combination with inorganic components with synergistic properties of both such as environment friendliness, biodegradability, flexibility of the former coupled with hardness, UV radiation stability, thermal stability and solvent resistance of the latter. In the present work, we have prepared DGEBA/Castor oil nanostructured biohybrid with a metal alkoxide as inorganic precursor for reinforcement of the matrix. The structure, morphology, thermal behavior and coating properties of the prepared biohybrid have been studied. Our studies revealed that the said biohybrid can be safely employed up to 180 °C as nanostructured protective coating.

Inherently conducting polymers (ICP) have attracted the attention of researchers because of their low cost and environmental stability. However, for commercial applications the poor processibility and solubility of ICPs have inhibited their widespread use. To avoid these disadvantages adducts, blends, and composites of conducting polymers have been developed. With a view to enhance the processibility of polyaniline (PANI), this work reports the synthesis of nano PANI polydihydroxydimethylsiloxane (PDMS) adduct and the formulation of its nanocomposite via the dispersion of this nano adduct in butylated melamine formaldehyde (BMF) cured soy alkyd (SA) in different weight loadings (0.25 wt %, 0.5 wt %, 1 wt %). The formation of PANI-PDMS adduct and its dispersion in butylated melamine formaldehyde (BMF) cured soy alkyd (SA) was confirmed by FTIR, UV-visible, 1H-NMR whereas the morphological characterization was done using TEM and X-ray diffraction analyses. The presence of PANI-PDMS in SA-BMF resin was found to significantly enhance the physicochemical, physicomechanical, and thermal properties which could be utilized in the development of corrosion protective paints and coatings. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012

The polymeric ligand (BFP) was synthesized by condensation of bisphenol-A, formaldehyde, and piperazine in alkaline medium at 70–80°C. The polymer–metal complexes were synthesized by the reaction of BFP with Mn(II), Co(II), Ni(II), Cu(II), and Zn(II) acetates in 1 : 0.5 (ligand : metal) molar ratio. All the synthesized polymers were characterized by elemental, spectral (infrared, 1H-NMR, and UV-Vis), magnetic moment measurements, and thermal (TGA) analysis. The ligand-field and nephelauxetic parameters have been determined from UV-Vis spectra using ligand-field theory. Elemental analyses indicate the association of water with metal for Mn(II), Co(II), and Ni(II), which is also supported by TGA. The antimicrobial activities of the synthesized polymers were studied by agar well diffusion methods against Bacillus subtilis, Bacillus megaterium, Staphylococcus aureus, Escherichia coli, Salmonella typhi, Pseudomonas aeruginosa, and Shigella boydii. The antimicrobial activity and thermal stability of Cu(II)–poly...

In this paper linseed oil based metallopolyesteramides (Mn(II)-/Co(II)-/Cu(II)-LPEA) containing metals [with half filled (d 5) and partially filled (d 7 and d 9) d orbitals] were synthesized via green route for the application of eco-friendly protective green material. This paper also described the role of occupancy of d orbitals on the performance of such polymers. The synthesis reaction was carried out in situ through condensation polymerization among linseed fatty amide diol (HELA), phthalic anhydride and respective metal acetates [M (OCOCH3)2; M = Mn(II), Co(II), Cu(II); different mole ratios] in absence of any harmful organic solvent. The structural determination (FTIR, 1H-NMR and 13C-NMR), curing, thermal, physico-chemical, physico-mechanical, anticorrosive/chemical resistance, antibacterial properties of Mn(II)-/Co(II)-/Cu(II)-LPEA were carried out. The curing mechanism of the resin was confirmed by the comparison of FTIR spectra of uncured and cured resin. The curing mechanism of Mn(II)-/Co(II)-/Cu(II)-LPEA is found to be contrary to that of reported oil based polymer that involves the lipid autoxidation (slow process) in which driers are required to speed up the room temperature curing process. The incorporation of metals in Mn(II)-/Co(II)-/Cu(II)-LPEA improved the thermal stability as compared to virgin linseed oil based polyesteramide (LPEA). Mn(II)-/Co(II)-/Cu(II)-LPEA also show excellent antibacterial performance against Staphylococcus aureus and Escherichia coli. The observed diversity in material properties suggests that Mn-LPEA may be useful as an eco-friendly protective green material with thermal stability up to 320–330 °C.

Ricinus communis (RC) oil-based materials are currently receiving increasing attention because of economic and environmental concerns. In the present work, RC oil—a natural triol has been utilized for the development of an advanced polymeric material—poly(urethane-ricinoleamide) (PUR) through very simple synthesis and curing strategy, omitting derivatization steps or side reactions, chain extenders and crosslinkers. The synthesis of PUR was carried out in two steps. The first step is the introduction of an amide group in the RC oil (89.5% ricinoleic acid) via base catalyzed amidation, which results in N, N-bis (2-hydroxyethyl) ricinoleamide (HERA). The second step is urethanation of HERA by the reaction of toluene-2,4-diisocyanate (TDI) in minimal possible organic solvent by one-shot technique, which results in the formation of polyurethane along with amide linkages. The physico-chemical and spectral studies (FT-IR, 1H-NMR and 13C-NMR techniques) confirm these two reactions and the structure of PUR. The resin was cured at ambient temperature without any cross linker. Solubility of the resin was investigated in different polar and non-polar solvents. Thermo-gravimetric analysis (TGA)/differential thermal analysis (DTA) and Differential Scanning Calorimetry (DSC) were used to determine the thermal stability and curing behavior of PUR. An ambient cured ricinoleamide modified polyurethane resin exhibited thermal resistance up to 200–220 °C.

In recent years, the development of ecofriendly biodegradable packaging materials from natural polymers particularly agricultural products has received increasing attention in an attempt to substitute the existing nonbiodegradable petro-based polymers. The need for new polymeric materials with tailored properties has driven the interest of industry and academia toward polymer blends. Vegetable oils are known to possess varying amounts of triglycerides having different unsaturation in their chains. Blending of commercial polymers with vegetable oil derived polymers is, therefore, expected to show synergetic behavior in terms of compatibility, physical, and mechanical characteristics with the latter. In an attempt to develop a biodegradable packaging material, blends of poly(vinyl alcohol) (PVA) and castor oil epoxy (COE) were synthesized in the weight ratios of 70/30, 60/40, 50/50, 40/60, and 30/70 by a microwave method. The effect of COE component as well as microwave irradiation on the compatibility and microstructural properties of the blends was investigated using spectral, viscometric, thermal, and morphological techniques. We observed tremendous improvement in mechanical properties after microwave irradiation for 120 s in COE/PVA 70/30 blend due to optimum cross-linking through hydrogen bond formation among the blend components. These results were supported by the SEM as well the TEM data. © 2011 Wiley Periodicals, Inc. Adv Polym Techn 30: 96–109, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/adv.20207

Conventional epoxy resin (DGEBA), in varying proportion, was used to modify epoxidized soybean oil (ESO) based systems, crosslinked by phthalic anhydride. The properties of DGEBA modified ESO systems were investigated by dynamic mechanical analysis, impact testing, tensile and flexural testing, scanning electron microscopy, and thermogravimetric analysis. Single loss factor tan δ peak was obtained for all of the modified systems. The results show the improvement in mechanical properties from their high crosslinking densities through the introduction of DGEBA with increase in initial degradation temperature, as obtained from thermogravimetric analysis. Results approaches to an ideal composition which gives the optimum property. POLYM. ENG. SCI., 2011. © 2011 Society of Plastics Engineers

The present study reports a novel approach for the rapid intercalation of linseed oil-derived fatty amide (LFA) in organo-montmorillonite (OMMT)-Cloisite® 93A. The intercalation of LFA (0.25, 0.5, and 1 wt %) in Cloisite® 93A was carried by varying the microwave irradiation time from 30 to 90 s. X-ray diffraction studies confirmed that microwave irradiation resulted in higher intercalation in a shorter reaction time. The basal spacings were shifted from 12.34 to 16.45 A on microwave irradiation for 30 s while exfoliation occurred at and beyond 60 s exposure. Controlled morphology of the nanohybrids was confirmed by transmission electron microscopy analysis on microwave irradiation for 30 s. This biomodified Cloisite® 93A could be used for the preparation of polyesters, polyesteramides, and polyurethanes of controlled morphology for various applications in biomedicine. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011

Efforts have been made for the development of high performance protective coating materials from non drying oil such as Pongamia glabra oil and their commercialization. Zn-containing self cured Pongamia glabr a oil based polyesteramide [Zn-APGPEA] resin was synthesized in situ by the reaction of Pongamia glabra fatty amide diol [HEPGA], poly(styrene-co-maleic anhydride) [SMA] and zinc acetate (different ratios) at 100 ± 5 °C in the presence of an acid catalyst. The physico-chemical characterizations of the resin were carried out by standard laboratory methods. The structural elucidation of the prepared resin was carried out by FTIR, 1 H NMR and 13 C NMR spectral techniques. The thermal behavior was studied by TGA technique. Antibacterial activity was measured by agar diffusion method against Escherichia coli and Staphylococcus aureus . The effect of the loading of zinc on properties of Zn-APGPEA film was also investigated. The properties of Zn-APGPEA compared with reported self cured Pongamia glabra polyesteramide [APGPEA]. Physico-mechanical and chemical/corrosion resistance test of Zn-APGPEA coatings showed that the presence of zinc metal in APGPEA considerably enhances the overall film performance and also improves antibacterial activity. Therefore, Zn-APGPEA can be used as an anti-corrosive and antibacterial coatings material which may substitute polymers obtained from petroleum.

Carboxylic group functionalized single walled (SW) and multi walled (MW) carbon nanotubes (CNT) have been incorporated into biopolymer matrix of chitosan (CH) to fabricate nanobiocomposite film onto indium–tin–oxide (ITO) coated glass plate for co-immobilization of rabbit-immunoglobulin (r-IgGs) and bovine serum albumin (BSA) to detect ochratoxin-A (OTA). The results of electrochemical studies reveal that presence of both CNT results in increased electro-active surface area of CH leading to enhanced electron transport in these nanobiocomposites. Moreover, in CH–SWCNT and CH–MWCNT nanobiocomposites the availability of NH2/OH group in CH and surface charged CNT also increases loading of the r-IgGs resulting in enhanced electron transport responsible for improved sensing characteristics. Compared to BSA/r-IgGs/CH–MWCNT/ITO immunoelectrode, electrochemical response studies of BSA/r-IgGs/CH–SWCNT/ITO immunoelectrode carried out as a function of OTA concentration exhibits improved linearity as 0.25–6 ng/dL, detection limit as 0.25 ng/dL, response time as 25 s, and sensitivity as 21 μA ng dL− 1 cm− 2 with the regression coefficient as 0.998.

In the present work, microwave assisted synthesis of metallopolyurethaneamide (MicMCPUA) has been carried out from Castor seed oil. The aim of the work is (i) to utilize non toxic, abundantly available bioresources—seed oils, (ii) to develop environment friendly metallopolymers, as vital alternate to petrobased materials, (iii) through “green” technology-microwave assisted synthesis, for the first time, (iv) for application as ecofriendly protective coatings. MicMCPUA was synthesized “in situ” under microwave irradiations by the reaction of microwave assisted diol Castor fattyamide (MicDCFA, as organic matrix) and zinc acetates (5, 10 and 15 wt%, as inorganic modifier) without any harmful solvents resulting in the formation of pre-metallopolymer (MicMDCFA) that was further reacted with toluylene-2,4-diisocyanate (TDI). The effect of metal incorporation on structural (spectral), physico-chemical and thermal stability of metallopolyurethaneamide was studied by standard methods. The coating performance of the metallopolyurethaneamide was also investigated by physico-mechanical and potentiodynamic polarization measurements. These studies revealed that MicMCPUA may find application as eco-friendly corrosion protective coatings safely up to 200–220 °C.

Bio-based epoxy materials were prepared from epoxidized soybean oil (ESO) with an anhydride-curing agent. Variation of anhydride/epoxy ratio (R) was found to have significant effect on the resulting properties of the materials. The properties were studied and compared by dynamic mechanical analysis (DMA), izod impact, scanning electron microscopy (SEM) and thermogravimetric analysis (TGA). The glass transition temperature reaches the maximum at stoichiometric ratio related to the cross-link density of the formed networks. These materials are thermally stable but exhibit a rapid decrease as the anhydride/epoxy ratio was increased.

Polyetheramide(PEtA) resin was synthesized by the condensation polymerization of N,N-bis(2-hydroxy ethyl) linseed oil fatty amide diol (HELA) with resorcinol. It was further treated with different percentage of toluylene 2-4-diisocyanate (TDI) to obtain the urethane modified polyetheramide resins (UPEtA). The structural elucidation of PEtA and urethane modified polyetheramide(UPEtA) were carried out by FT-IR, 1H-NMR and 13C-NMR spectroscopic techniques. These analyses confirm the formation of PEtA and UPEtA. Physico-chemical and physico-mechanical analysis were performed by standard laboratory methods. The resin composition UPEtA-24 showed best physico-mechanical properties with scratch hardness 2.0 kg, impact resistance 150 lb/in. and good bending ability. The thermal stability and curing behavior of polymers were respectively studied by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). Thermal analysis shows that these coatings can be used safely upto 190 °C. The coatings of UPEtA resins were prepared on mild steel strips. The anticorrosive behavior of UPEtA coatings were investigated in acid, alkali, water and xylene. All the coatings exhibit good chemical resistance performance in acid, alkali, saline and organic solvents, while the resin UPEtA-24 shows the best performance.

A nanostructured iron oxide (NanoFe(3)O(4), particle size ca. 25 nm and roughness ca. 2:1 nm) film deposited onto a hydrolyzed indium-tin-oxide (ITO) coated glass plate has been used to immobilize cholesterol oxidase (ChOx) to fabricate an impedimetric cholesterol sensor. Electrochemical studies reveal that surface charged Fe(3)O(4) nanoparticles provide better conformation for ChOx loading resulting in enhanced electron transfer between ChOx and the electrode. Impedimetric response studies of the ChOx/NanoFe(3)O(4)/ITO bioelectrode exhibit improved linearity (2.5-400 mg/dL), low detection limit (0.25 mg/dL), fast response time (25 s), high sensitivity (86 Omega/mg dL(-1)/cm(-2)) and a low value of the Michaelis-Menten constant (K(m) 0.8 mg/dL) with a regression coefficient of 0.997.

Summary: An attempt has been made to synthesize boron containing poly (urethane-fattyamide) [B-PUPGFA] through the incorporation of boron in the backbone of non drying oil such as Pongamia glabra oil derived poly (urethane-fattyamide). The synthesis route involves 50% reduction in the use of harmful volatile organic contents [VOCs] and was carried out in situ by condensation reaction between N, N′-bis (2-hydroxyethyl) Pongamia glabra fattyamide and boric acid without solvent followed by the addition polymerization with toluene diisocyanate in minimum solvent. Spectral (FTIR, 1H-NMR and 13C-NMR), physico-chemical, physico-mechanical and chemical resistance of B-PUPGFA was carried out by standard laboratory methods. The antibacterial performance of B-PUPGFA was done by agar diffusion method against E. coli and S. aureus. The aforementioned performance of B-PUPGFA was compared with Pongamia glabra oil based virgin poly (urethane-fattyamide) [PUPGFA]. It is observed that the incorporation of boron has a significant influence on the overall performance of B-PUPGFA film, which shows antibacterial activity against E. coli and S. aureus. Therefore, B-PUPGFA serves as novel and promising biomaterial candidate for use as anticorrosive and antibacterial coating material.

With the aim to utilize linseed oil epoxy – a product from sustainable resource for the processing of hard polymers, blends of linseed oil epoxy (LOE) with polyvinylchloride (PVC) were prepared for the first time by solution blending of the requisite amounts of the two components in the weight ratios LOE/PVC- 85/15, 65/35, 55/45, 45/55, 35/65, and 15/85 through solution method by mixing in tetrahydrofuran (THF). The miscibility of the two components in solution phase was investigated by relative viscosity, reduced viscosity and density measurements. The blend with 85 wt% of LOE yielded stiff and flexible films with maximum stress of 33 MPa and 216% elongation at break. Biodegradability of these blends has been studied by soil burial test, enzymatic degradation, and hydrolytic degradation in phosphate buffer. The blend LOE/PVC 85/15 showed the highest biodegradation of 68 wt% in 6 months in the soil burial test. The degradability was found to increase with the increase in LOE content in the blend compositions. The potential applications for such sustainable resource based blend films include packaging materials and biodegradable plastic sheets which can be formed into products such as bio-bags.

Polyol/nanosilica organic-inorganic hybrids (Si/Lpol) were prepared through facile sol-gel chemistry. Tetraethoxyorthosilane (TEOS) and linseed polyol (Lpol) obtained by hydroxylation of linseed oil were used as inorganic and organic precursors, respectively. Si/Lpol was further treated with toluene-2,4-diisocyanate (TDI) to obtain silica embedded polyurethane (Si/LPU). The structure of the organic-inorganic hybrid was confirmed by FTIR, 1 H NMR, and 13 C NMR spectral analysis. The polyol/nanosilica network shows strong interaction with the remnant polyol backbone through hydrogen bonding, which also has bearing on Tg of polymers. Morphological studies of Si/LPU show the formation of uniform, spherical silica nanoparticles of 2-30 nm size embedded in the polymer matrix. Si/LPU was further reinforced with 2 and 5 wt.-% fumed silica (FS-Si/LPUs); their morphology revealed a carpet layer formation on top of Si/LPU. Thermogravimetric analysis showed improved thermal stability of Si/LPU and FS-Si/LPUs. The polymers exhibit mild to moderate antibacterial behavior against E. coli and S. aureus, respectively, and will pave way in plethora of biological and chemical applications as coating materials.

Linseed amide diol [HELA] was used as modifier for conventionally available epoxy resin [DGEBA] by blending in different ratio. Blends [DGEBA/HELA] were subjected to spectral, physico-chemical, ageing and antibacterial studies. Interesting features of the blends were complete miscibility of HELA with DGEBA, principally due to hydrogen bonding and chemical reaction between the two constituents, and their moderate antibacterial activity against S. aureus . DGEBA/HELA blends were further treated with triethylenetetramine [TETA-A] [DGEBA/HELA/A] as curing agent to evaluate their performance as corrosion protective coating materials. DGEBA/HELA/A coatings showed good physico-mechanical and chemical resistance behavior, in particular against alkaline media. Thermal analysis of DGEBA/HELA/A revealed their single to multi-step degradation behavior with safe usage upto 220 °C. Our investigations confirm the dual role of HELA as environment-friendly, reactive-modifier and mild curing agent for epoxy resins. Besides, DGEBA/HELA/A may find potential applications as “solvent free”, ambient temperature cured antibacterial coating materials.

Ethylene diamine polyesteramide (Ed-PEA) was synthesized from N, N-bis (2-hydroxy ethyl) linseed oil fattyamide and ethylene diamine tetra acetic acid through condensation polymerization. It was further treated with toluylene 2,4-diisocyanate (TDI) in different weight percentage to obtain urethane-modified polyesteramide (Ed-UPEA). The structural elucidation of Ed-PEA and Ed-UPEA were carried out by FTIR, 1H-NMR, and 13C-NMR spectroscopic techniques. Thermal studies of these resins were carried by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). The coatings of urethane-modified polyesteramide were prepared on mild steel strips and their anticorrosive behavior of in acid, alkali, water, and xylene were investigated. Thermal stability performance suggests that the system could be safely used upto 200°C. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009

Processibility is one of the important requirements for the commercial utilization of conducting polymers. Studies on composites and blends based on nano polyaniline (PANI) dispersions have become the subject of scientific curiosity with regard to their morphology, stability, and electron transport properties. In general, polymer nanocomposites are made by dispersing inorganic or organic nanoparticles into either a conventional thermoplastic or thermoset polymer. The present study reports the synthesis of nanostructured MO-PANI and castor oil polyurethane (COPU)–based composites. The effect of loading of nanostructured MO-PANI in COPU on the spectral, physicochemical and morphological properties has been analyzed. © 2009 Wiley Periodicals, Inc. Adv Polym Techn 28:26–31, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/adv.20143

The aim of this work was to investigate the structures and properties of boron incorporated linseed oil polyols (BPEPs) and their polyurethanes (BPEPUs). Hydroxylation was performed in situ using H2O2 and acetic acid; the syntheses of BPEPs and BPEPUs involves polyesterification and polyaddition reactions following “single-pot, multi-step” reactions strategy. Spectral (IR, 1H-NMR, and 13C-NMR), physicochemical, thermal (TGA, DSC), physico-mechanical analyses and corrosion/chemical resistance performance of aforementioned resins confirmed the incorporation of boron in polyol and polyurethane backbone. BPEPUs followed a clear cut “three step-ambient temperature” curing strategy. They showed very good resistance to 5 wt % HCl, 3.5 wt % NaCl (unaffected for 16 and 14 days, respectively), moderate alkali resistance and moderate to good antibacterial activity against E. coli and S. aureus. Our investigations reveal that (i) the incorporation of boron has significant influence on the structural, physicochemical aspects, physico-mechanical, chemical resistance behavior, and thermal stability of polyurethanes, (ii) boron linkages play dual role, both as cross linker and modifier, and (iii) BPEPUs may serve as efficient corrosion protective material, which may be safely employed upto 230°C. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010

Nanotechnology has emerged as a subject of immense academic interest and excitement in the past few decades. The immediate goal of this science aims at the production of high performance nanomaterials. The present study reports comparative investigations on the in situ polymerization of polyaniline (PANI), and its derivatives poly(1-naphthylamine) (PNA) and poly(o-toluidine) (POT) within the camphor sulphonic acid (CSA) modified montmorillonite (MMT) layers. The polymerization as well as intercalation of the conducting polymers was confirmed by FT-IR, UV-visible spectroscopies, and XRD studies, whereas the morphology of the nanocomposites was analyzed by TEM studies. It was found that the PANI derivatives (PNA and POT) revealed higher intercalation as compared with PANI. The morphology of nanocomposites was found to be governed by the type of conducting polymer intercalated. A large variation in the morphology as well as particle size was observed between the nanocomposites of PANI and its derivatives. The conductivity was found to be in the range of 10−3–10−2 S·cm−1. POLYM. COMPOS., 2010. © 2009 Society of Plastics Engineers

Fumed silica nanoparticles (NanoSiO2) and chitosan (CH) based nanobiocomposite film have been used to co-immobilize rabbit-immunoglobulin antibodies (r-IgGs) and bovine serum albumin (BSA) for ochratoxin-A (OTA) detection. The observed three-dimensional (3D) arrangement of NanoSiO2 in CH matrix via hydrogen bonding, available NH2/OH groups and excellent film-forming ability of CH results in increased effective surface area of CH–NanoSiO2 nanobiocomposite for r-IgGs immobilization. Electrochemical studies suggest that presence of NanoSiO2 leads to enhanced electrochemical behaviour of CH resulting in increased electron transport between the medium and the electrode. BSA/r-IgGs/CH–NanoSiO2/ITO immunoelectrode exhibits improved sensing characteristics such as linearity (0.5–6 ng/dL), detection limit (0.3 ng/dL), response time (25 s) and sensitivity (18 μA ng/dL cm−2) with correlation coefficient as 0.98. Keywords: Fumed silica, Chitosan, Nanobiocomposite, Immunosensor, Ochratoxin-A

Nucleic acid sensor has been fabricated via immobilization of single standard calf thymus deoxyribose nucleic acid (ssCT-DNA) onto chitosan (CH)-iron oxide (Fe3O4) nanoparticles based hybrid nanobiocomposite film deposited onto indium-tin-oxide (ITO) coated glass for pyrethroids [cypermehtirn (CM) and permethrin (PM)] detection. The ssCT-DNA immobilized onto CH-Fe3O4 nanocomposite/ITO electrode has been characterized using scanning electron microscopy (SEM), UV–visible, Fourier transform infrared (FTIR) spectroscopy, electrochemical impedance spectroscopy (EIS) and differential pulse voltammetry (DPV) techniques. This disposable ssCT-DNA/CH-Fe3O4 nanobiocomposite/ITO bioelectrode is stable for about two months under refrigerated conditions and can detect CM (0.0025–2 ppm) and PM (1–300 ppm) using DPV technique within 25 s and 40 s, respectively.

The present study reports the synthesis and characterization of waterborne interpenetrating network (IPN) of epoxy-acrylic-oleic acid (EpAcO) with butylated melamine formaldehyde (BMF). The effect of BMF on the formation of IPN was investigated in terms of physicochemical, spectral, morphological, and thermal analyses. The coating properties of the IPN were investigated for their physicomechanical, corrosion resistance, and antimicrobial activity. The formation of the IPN was confirmed by FTIR and 1H NMR analyses as well as physicochemical properties. The EpAcO-BMF IPN coatings were found to exhibit far superior corrosion resistance performance and good thermal stability when compared with the reported waterborne epoxy acrylic-melamine formaldehyde systems [EpAc-MF]. The preliminary antimicrobial investigations of the IPNs were carried out by agar diffusion method against some bacteria and fungi. The results revealed that antimicrobial activities were enhanced upon the formation of IPN. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009

Commercially available biaxially oriented polypropylene (BOPP) films were irradiated with 90 MeV Ni 8+ ions and 120 MeV Ag 11+ ions at different fluencies varying from 10 10 to 3 x 10" ions/cm 2 and then grafted with glycidyl methacrylate (GMA) using benzoyl peroxide (BPO) as chemical initiator. As the reaction temperature was below the melting point, PP was modified in the solid phase. A comparative study for the GMA grafting using BPO initiator in virgin as well as in the SHI irradiated BOPP indicates that the heterogeneity of the grafted GMA domains on the BOPP surface was higher in SHI irradiated system. Contact angle measurements showed an increasingly hydrophilic nature in the direction from pure PP to grafted PP-g-GMA. These results are intended to benefit the synthesis and properties of a functional polymer, useful in developing a compatibilizer for PP/Cloisite 30B nanocomposites.

The present work study reports the comparative corrosion protective performance of nanostructured methyl orange (MO) doped polyaniline (PANI) and camphorsulphonic acid (CSA) doped poly(1-naphthylamine) (PNA) dispersed polyurethane-based composite coatings against mild steel (MS). The influence of the dopant on the passivation of metal was analyzed using two different dopants. The nanostructure of the conducting polymers—MO-PANI and CSA-PNA was confirmed by transmission electron microscopy (TEM). The corrosion protective performance of the coatings against MS was evaluated by the physico-mechanical properties and corrosion rate measurements.

The present study reports a facile technique for the synthesis of crystalline super paramagnetic nano ferrite (Fe3O4) particles using diethyl amine as a soft template. The spectral properties of Fe3O4 nanoparticles were characterized by UV–visible and Fourier Transform Infrared (FTIR) spectroscopies while the crystalline structure and particle size was estimated using X-Ray diffraction (XRD) as well as transmission electron microscopy (TEM) techniques. The super paramagnetic behavior of Fe3O4 nanoparticles was determined using vibrating sample magnetometer (VSM) at 300 K. The results of the studies revealed that this technique could be adopted to synthesize agglomerate free super paramagnetic Fe3O4 nanoparticles which may find potential application in the filed of biosensor and corrosion protective coatings.

Efficient utilization of inherently conducting polymers in nano technological applications faces the challenge to assemble them into highly ordered structures which may yield novel properties. The present study reports for the first time the synthesis and characterization of nanostructured poly (1-naphthylamine) (PNA) dispersed polyvinyl alcohol (PVA) composites. The composites were prepared by loading PNA from 2 wt% to 10 wt% in PVA in aqueous as well as nonaqueous media. The composites were characterized by UV–visible spectroscopy, TEM, stress–strain studies, electrical conductivity measurements and moisture absorption studies under controlled humidity. A discrete but uniform distribution of nanoparticles was obtained in PNA/PVA composites synthesized in water having particle size between 5 and 30 nm. A self assembled network of nanostructured PNA particles was obtained in case of PNA/PVA composites synthesized in N -methylpyrolidone (NMP) with particle sizes between 10 and 65 nm. The variation in the nanostructured morphology of PNA particles in PVA matrix in the two cases resulted from the pronounced interaction of PVA with NMP through hydrogen bonding. This leads to the formation of a homogeneous matrix that facilitates the formation of a self assembled network of PNA nano particles. In case of PNA/PVA composites synthesized in water, lower affinity of PVA towards water was responsible for a discrete, agglomerate free distribution of PNA particles. We have found that the PNA/PVA nano composite synthesized in water exhibited good mechanical properties and electrical conductivity (8.1 × 10 −1 S/cm) as well as lowest moisture absorption (4 wt%) which holds potential for use in semiconductor and biomedical devices.

Investigations on the synthesis of nanoconducting polymers have gained much popularity during the past few decades. The processibility of the nanostructured conducting polymers is poor, which hinders their commercial application. Considering the drawbacks of nanostructured conducting polymers, this article reports for the first time the synthesis of processible composites of nanostructured poly(1-naphthylamine) (PNA), a polyaniline derivative with poly(vinyl chloride) (PVC). The composites were prepared by loading different weight ratios of PNA (2–10 wt%) in PVC. The composites were characterized by spectral, thermal, morphological, and conductivity studies. The particle size of PNA/PVC composites was confirmed by transmission electron microscopy and was found to be in the range of 5–20 nm. The highest conductivity of 2.5 × 10−2 S/cm was obtained in the composite with 4 wt% loading of PNA. The high conductivity of the composites was correlated to the agglomerate-free uniform dispersion of self-assembled nanofibrillar network of PNA particles in the PVC matrix. The PNA/PVC composites exhibited good mechanical properties, which holds potential for use in semiconductor nanodevices. POLYM. COMPOS., 2009. © 2008 Society of Plastics Engineers

Urease (Ur) and glutamate dehydrogenase (GLDH) have been co-immobilized onto superparamegnatic iron oxide (Fe3O4) nanoparticles-chitosan (CH) based nanobiocomposite film deposited onto indium-tin-oxide (ITO) coated glass plate via physical adsorption for urea detection. The magnitude of magnetization (60.9 emu/g) of Fe3O4 nanoparticles (∼22 nm) estimated using vibrating sample magnetometer (VSM) indicates superparamagnetic behaviour. It is shown that presence of Fe3O4 nanoparticles results in increased active surface area of CH-Fe3O4 nanobiocomposite for immobilization of enzymes (Ur and GLDH), enhanced electron transfer and increased shelf-life of nanobiocomposite electrode. Differential pulse voltammetry (DPV) studies show that Ur-GLDH/CH-Fe3O4/ITO bioelectrode is found to be sensitive in the 5–100 mg/dL urea concentration range and can detect as low as 0.5 mg/dL. A relatively low value of Michaelis–Menten constant (Km, 0.56 mM) indicates high affinity of enzymes (Ur and GLDH) for urea detection.

A novel attempt has been made to develop ambient cured polyamine amide (PAA) resins by the condensation polymerization reaction of oil fatty amide diol (N,N-bis 2-hydroxy ethyl linseed oil fatty amide) (HELA) and o-phenylene diamine, which was further modified by poly(styrene-co-maleic anhydride) (SMA) at different phr (parts per hundred part of resin) to get a series of PAA–SMA resins. The structural elucidation of HELA, PAA and PAA–SMA were carried out by FT-IR, 1H-NMR and 13C-NMR spectroscopic techniques. The physico-chemical and physico-mechanical analyses were carried out by standard laboratory methods. Thermal analyses of these resins were accomplished by thermogravimetric analyses (TGA) and differential scanning calorimetry (DSC) techniques. Coatings of PAA–SMA were prepared on mild steel strips to evaluate their physico-mechanical and chemical/corrosion resistance performance under various corrosive environments. It was found that among the PAA–SMA systems, PAA-35 showed the best physico-mechanical and corrosion resistance performance. Thermal studies reveal that the coatings can be safely used up to 305 °C.

Poly (urethane fatty amide) [PULFA] resin was synthesized by using a one-shot technique at room temperature from diol linseed fatty amide [DLFA; a monomer obtained from the aminolysis of renewable resource, such as linseed oil with diethanolamine and sodium methoxide used as a catalyst], 1.0 moles, and varying ratio of toluylene-2,4(6)-diisocyanate [TDI, 0.08–1.5 moles] in minimum amount of xylene without any chain extender and catalyst. In this process phthalic acid/anhydride which is normally used in the synthesis of polyesteramide was completely replaced by TDI as in case of uralkyd. The reaction mechanism of the same has been discussed here. The mode of reaction and structure of the resin was confirmed by physico-chemical tests and spectral analysis. The performance of the coatings on mild steel strips was tested by physico-mechanical and chemical/corrosion resistance tests. Thermo gravimetric analysis [TGA] and differential scanning calorimetry [DSC] techniques were used to investigate the thermal stability and curing behavior of the resin. The aforementioned properties of newly synthesized resin were compared with those of reported linseed oil-based polyesteramide urethane [Ur-LPEA, synthesized by partial replacement of phthalic anhydride by TDI] and uralkyd. The newly synthesized resin has shown improved physico-mechanical and corrosion resistance performance to Ur-LPEA and alkyd, whereas to those of uralkyd has comparable results. The PULFA resin exhibits not only superior properties to some of the reported resins, but also helps in the conservation of energy by being synthesized at room temperature as compared to other similar reported systems which were synthesized at reasonably high temperatures. The present study reveals that the PULFA resin can be used as a substitute to Ur-LPEA, alkyd and uralkyd in the field of corrosion protective paints and coatings.

The growing environmental concerns have led to the formulation of new coating strategies by employing inherently conductive polymers (ICPs) as a key component in order to eliminate the toxic heavy metals from protective coatings. Also, the renewable resources are given increasing priority within chemical industry and the energy community. Emphasis is therefore, processing of polymers from renewable resources which show advantages when compared with petrochemical raw materials and are regarded as an ideal raw material. The present work reports the investigations on the corrosion-resistance performance of soya oil alkyd, containing nano polyaniline (PANI) against mild steel (MS). The corrosion-protective performance was evaluated in terms of physico-mechanical properties, corrosion rate, open circuit potential measurements (OCP) and scanning electron microscopy (SEM) studies. The performance was compared to the reported PANI coatings.

Pongamia glabra seed oil (PGSO) – a non-edible, non-drying oil; a sustainable resource has found application as alkyds, epoxies and polyesteramides in paints and coatings. Generally, PGSO based polymeric coatings are obtained by curing at elevated temperature. Efforts have been made to cure PGSO at room temperature by simple route modification. Self-cured Pongamia glabra oil based on polyesteramide (APGPEA) resin was synthesized by the reaction between Pongamia glabra oil modified fatty amide diol (HEPGA) with polystyrene co-maleic anhydride (SMA). After complete synthesis of APGPEA, phthalic anhydride modified polyesteramide (APGPEAPh) was synthesized in situ by a minor addition of phthalic anhydride (PA) to APGPEA in order to improve the performance of the latter. The effect of the SMA and PA introduction on properties of PGPEAPh film was also investigated. The physico-chemical characteristics of both resins were obtained by standard laboratory methods. The structural elucidation of these resins was carried out by FT-IR, 1H-NMR and 13C-NMR spectral techniques. The thermal behavior was studied by TGA. Curing was studied by DSC and FT-IR techniques. It was observed that APGPEA and APGPEAPh resins significantly improve the drying property in contrast to the previously reported polyesteramides cured at high temperature. Physico-mechanical and chemical/corrosion resistance tests of APGPEAPh coatings showed that the presence of phthalic anhydride in APGPEA enhanced the physico-mechanical and corrosion resistance considerably. The APGPEAPh resin appears to be sustainable aspirant biomaterials for anticorrosive surface coatings which may substitute polymers obtained from petroleum, potentially scarce resource.

Iron oxide (Fe(3)O(4)) nanoparticles prepared using co-precipitation method have been dispersed in chitosan (CH) solution to fabricate nanocomposite film on indium-tin oxide (ITO) glass plate. Glucose oxidase (GOx) has been immobilized onto this CH-Fe(3)O(4) nanocomposite film via physical adsorption. The size of the Fe(3)O(4) nanoparticles estimated using X-ray diffraction (XRD) pattern and transmission electron microscopy (TEM) has been found to be approximately 22 nm. The CH-Fe(3)O(4) nanocomposite film and GOx/CH-Fe(3)O(4)/ITO bioelectrode have been characterized using UV-visible and Fourier transform infrared (FTIR) spectroscopic and scanning electron microscopy (SEM) techniques, respectively. This GOx/CH-Fe(3)O(4)/ITO nanocomposite bioelectrode has response time of 5s, linearity as 10-400 mgdL(-1) of glucose, sensitivity as 9.3 microA/(mgdLcm(2)) and shelf life of about 8 weeks under refrigerated conditions. The value of Michaelis-Menten (K(m)) constant obtained as 0.141 mM indicates high affinity of immobilized GOx towards the substrate (glucose).

The efficient utilization of inherently conducting polymers in nanotechnological applications faces challenges in processing them into highly ordered structures that yield novel properties. This paper reports a comparative study on the nanocomposites of poly(1-naphthylamine) (PNA), having a fused aromatic ring, and its conductive nanocomposites with polyvinyl alcohol (PVA) and polyvinyl chloride (PVC). The composites were prepared by two different methods: (a) dispersion of PNA in PVA and (b) in situ polymerization of PNA in PVC. These nanocomposites were characterized by UV–visible spectroscopy, TEM, stress, strain, and conductivity measurements. The variation in the nanostructured morphology of PNA particles in PVA as well as PVC matrix in the two cases resulted from the pronounced interaction of PNA with PVA through hydrogen bond, forming a homogeneous matrix that facilitates the formation of a self-assembled network of PNA nanoparticles. In case of PNA/PVC composite, a discrete, agglomerate-free distribution of PNA particles was obtained. The results revealed that an appropriate choice of synthesis conditions offers a possibility to improve not only the processability but also the pattern of distribution as well as the stability of PNA particles. © 2008 Wiley Periodicals, Inc. Adv Polym Techn 27:40–46, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/adv.20117

PurposeThe purpose of this paper is to report a comparative study of conducting polymer (CP) dispersed oil polyurethane coatings derived from a sustainable resource, i.e. polyaniline (PANI)/coconut oil polyesteramide urethane (CPEAU) and poly(1‐naphthylamine) (PNA)/linseed oil polyurethane (LPUA) coatings.Design/methodology/approachThe coatings were prepared chemically and were characterized for their physico‐chemical, physico‐mechanical, corrosion protective efficiency, and open circuit potential measurements. The morphological analysis of the corroded carbon steel (CS), coated uncorroded CS, and coated corroded CS specimens, was carried out by SEM analysis.FindingsThe study revealed that the presence of a CP enhanced the corrosion protective efficiency of the sustainable resource‐based organic coatings. The type of CP used also played a major role in defining the corrosion resistance behavior of the coating materials.Originality/valueThe comparative study of anticorrosive properties of CP with oil‐based polyurethane blends has been studied for the first time.

Nanostructured materials have been establishing themselves as modem generation of high performance materials in many areas ranging from automotive engineering to bioengineering owing to a vast array of their unique properties. Improvements in environmental impact can also be achieved utilizing nanostructure particulates in coating and eliminating the requirement of toxic inhibitors such as chromates. The paper reports a comparative study on the corrosion resistance performance of soya oil alkyd containing nanostructured polyaniline (PANI) and poly(1-naphthylamine) (PNA) composite coatings. The corrosion protective performance was evaluated by physico-mechanical properties, corrosion rate, open circuit potential measurements, and SEM studies. The PNA/ alkyd composite coatings were found to show far superior corrosion resistance performance as compared to PANI/alkyd system.

Cholesterol biosensor has been fabricated by covalently coupling cholesterol oxidase (ChOx) via glutaraldehyde onto electrochemically prepared polyaniline film in presence of TritonX-100 [4-(1,1,3,3-tetramethylbutyl) phenyl polyethylene glycol], a non-ionic surfactant onto indium-tin-oxide (ITO) glass substrate. These ChOx/PANI-TX-100/ITO bioelectrodes have been characterized using Fourier transform infrared (FTIR) spectroscopy, cyclic voltammetry (CV) and scanning electron microscopy (SEM) techniques. The results of response measurements carried out on ChOx/PANI-TX-100/ITO bioelectrodes using amperometric and photometric techniques, reveal detection limit as 5 mg/dl, linearity from 5 to 400 mg/dl of cholesterol and sensitivity as 131 μA/(mg/dl cm−2). These biosensing electrodes are thermally stable up to 65 °C, can be used about 20 times and have a shelf-life of about 10 weeks when stored at 4 °C. Attempts have also been made to utilize the ChOx/PANI-TX-100/ITO bioelectrodes for estimation of free cholesterol concentration in serum samples.

It was for the first time we attempted to develop zinc and cadmium incorporated linseed oil based poly(esteramide-urethane) [Zn/Cd-LPEAUr], and investigated their structure, mechanism, and properties. The resin was synthesized in situ by the reaction of linseed oil derived fatty amide diol [HELA], divalent zinc/cadmium acetate and toluylene-2, 4 (6), diisocyanate [TDI; 2–12 wt %] with minimal solvent. The structural elucidation of Zn/Cd-LPEAUr was carried out by FTIR, 1H-NMR, and 13C-NMR spectral techniques. TGA and DSC techniques were used to measure the thermal stability and curing behavior of these resins, respectively. The physicomechanical and chemical/corrosion resistance properties were investigated by standard laboratory methods. The performance of Zn/Cd-LPEAUr coating was compared with reported oil based polyesteramide. Antibacterial test of the resins were performed by agar diffusion method against E. coli and S. aureus, and compared with those of petroleum-based metal containing polyurethanes. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008

Studies on composites and blends based on nanostructured polyaniline (PANI) have become the subject of scientific curiosity with regard to their morphology, stability, and electronic properties. Nanocomposites of conducting polymers display improved mechanical, electrical, optical, and catalytic properties owing to their remarkable nanostructure. The present study reports the synthesis of nanostructured PANI and its composites based on soy oil alkyd. The effect of loading of nanostructured PANI on the physiochemical, physicomechanical, morphological, and thermal properties of the composite has been analyzed. POLYM. COMPOS., 2010. © 2008 Society of Plastics Engineers

The rabbit immunoglobulin antibodies (IgGs) have been immobilized onto nanobiocomposite film of chitosan (CH)–iron oxide (Fe3O4) nanoparticles prepared onto indium–tin oxide (ITO) electrode for detection of ochratoxin-A (OTA). Excellent film forming ability and availability of –NH2 group in CH and affinity of surface charged Fe3O4 nanoparticles for oxygen support the immobilization of IgGs. Differential pulse voltammettry (DPV) studies indicate that Fe3O4 nanoparticles provide increased electroactive surface area for loading of IgGs and improved electron transport between IgGs and electrode. IgGs/CH–Fe3O4 nanobiocomposite/ITO immunoelectrode exhibits improved characteristics such as low detection limit (0.5 ng dL−1), fast response time (18 s) and high sensitivity (36 μA/ng dL−1 cm−2) with respect to IgGs/CH/ITO immunoelectrode. Keywords: Electrochemical immunosensor, Fe3O4 nanoparticles, Chitosan, Bionanocomposite, Ochratoxin-A

A novel attempt has been made to incorporate boron in the backbone of castor oil to develop boron-modified polyester (BCPE) and polyurethane (BPU). The overall reaction strategy involved “single pot multiple reactions” in minimum solvent achieving about 50% reduction in the use of volatile organic compounds (VOCs) during the synthetic procedure. Spectral (I.R., 1 H NMR and 13 C NMR), physicochemical and thermal (TGA and DSC) analyses of BCPE and BPU were carried out by standard methods. The physico-mechanical and corrosion/chemical resistance performances (in various corrosive media) tests of BPU coatings were also conducted to evaluate their coating properties. These studies revealed that (i) the incorporation of boron has a significant influence on structural and physico-chemical aspects, thermal stability as well as on coating properties of BPUs, (ii) interestingly, BPUs showed very good performance in alkaline media (unaffected in 5 wt% NaOH for 50 h) as compared to their other previously reported oil-based counterparts, (iii) boron, here, acts both as a modifier and crosslinker and (iv) BPUs serve as novel and promising candidates for use as corrosion protective coating material, which can be safely employed up to 220 °C.

Modern engineering science and nanotechnology have hastened the development of high performance corrosion-resistant coatings having a broad spectrum of effectivity under a wider range of hostile environments. The formulation of such coating systems is expected to cause a major revolution in the corrosion world. Conducting polymers have recently proved to be an effective alternative to phosphate–chromate pretreatment that is hazardous due to toxic hexavalent chromium. Moreover, improvements in environmental impact can be achieved by utilizing nanostructured particulates in coating and eliminating the requirement of toxic solvents. The paper reports some preliminary investigations on the corrosion resistance performance of nanostructured methyl orange (MO)-doped polyaniline (PANI)/castor oil polyurethane (COPU) composite coatings on mild steel (MS). The nanostructure of the MO-PANI was confirmed by transmission electron microscopy (TEM). The corrosion protective performance was evaluated by physico-mechanical properties, corrosion rate, and open circuit potential measurements. These coatings were found to act as “corrosion sensors” by exhibiting different colors when placed in acid as well as alkaline media. The protective behavior of coatings was attributed to the formation of a passive iron oxide/dopant layer at the metal-coating interface that impedes the penetration of the corrosive ions. Copyright © 2008 John Wiley & Sons, Ltd.