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Local delivery of anticancer agents via injectable hydrogels could be a promising method for achieving spatiotemporal control on drug release as well as minimizing the disadvantages related to the systemic mode of drug delivery. Keeping this in mind, we report the development of N,O-carboxymethyl chitosan (N,O-CMCS)-guar gum-based injectable hydrogels for the sustained delivery of anticancer drugs. The hydrogels were synthesized by chemical crosslinking of multialdehyde guar gum (MAGG) and N,O-CMCS through dynamic Schiff base linkages, without requiring any external crosslinker. Fabrication of injectable hydrogels, involving N,O-CMCS and MAGG via Schiff base crosslinking, is being reported for the first time. The hydrogels exhibited pH-responsive swelling behavior and good mechanical properties with a storage modulus of about 1625 Pa. Due to the reversible nature of Schiff base linkages, hydrogels displayed excellent self-healing and thixotropic properties. Doxorubicin (Dox), an anticancer agent, was loaded onto these hydrogels and its release studies were conducted at pH 7.4 (physiological) and pH 5.5 (tumoral). A sustained release of about 67.06% Dox was observed from the hydrogel after 5 days at pH 5.5 and about 32.13% at pH 7.4. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay on the human embryonic kidney cell line (HEK-293) and the hemolytic assay demonstrated the biocompatible nature of the hydrogels. The Dox-loaded hydrogel exhibited a significant killing effect against breast cancer cells (MCF-7) with a cytotoxicity of about 72.13%. All the data presented support the efficiency of the synthesized N,O-CMCS/MAGG hydrogel as a biomaterial that may find promising applications in anticancer drug delivery.

Magnesium ferrite (MgFe2O4) nanorods and magnesium ferrite/polythiophene (MgFe2O4/PTh) composites have been fabricated by sol–gel and in-situ emulsion polymerization approach to investigate EMI (electromagnetic interference) shielding activity in the X-band region. The encapsulation of MgFe2O4 nanorods by conducting PTh decreased the coercivity and improved the conductivity of the composites. The composite with a maximum loading of MgFe2O4 nanoparticles (MP-21; MgFe2O4:PTh = 2:1) displayed superior magnetic moment (23.27 emu/gm) and coercivity (0.023 kOe). In addition, the composite (MP-21) exhibited the highest SE (shielding effectiveness) of − 40.17 dB at 10.29 GHz by 1 mm thick pellet for X-band region (8.2–12.4 GHz). The excellent shielding behavior of the composite is attributed to the synergistic effect of these two moieties resulting in the high dielectric and magnetic loss. Moreover, the porous and rod-like morphology of these composites further induces microwave absorption ability. These results revealed that MgFe2O4/PTh composite showed the maximum EMI shielding property, which can find potential application as a lightweight, high-performance EMI shielding material.

Gum arabic with multialdehyde groups (GAMA) was synthesized and utilized as a naturally derived macromolecular and nontoxic cross-linker to develop biocompatible and smart succinic anhydride-modified chitosan (SCS)-based injectable hydrogels for the first time. Aqueous solutions of GAMA and SCS were mixed at 37 °C to obtain hydrogels through pH-responsive, dynamic, and biodegradable Schiff base linkages. The effect of concentration of GAMA on hydrogel stiffness, swelling, morphology, and drug release behavior was investigated. These hydrogels exhibited outstanding self-healing and mechanical properties. Nanocurcumin as a chemotherapeutic agent was synthesized and loaded into these hydrogels for release studies carried out at pH 7.4 and 5.5. MTT assay revealed that these hydrogels are nontoxic to human embryonic kidney cell line (HEK-293). Loaded hydrogels demonstrated significant cytotoxicity against breast cancer cell line (MCF-7). Thus, the present strategy may find promising application for controlled delivery of anticancer drugs for treating locally accessible cancers.

The present study reports the formulations of biocompatible nanocomposite hydrogels using chitosan (CH), poly(vinyl alcohol) (PVA), oleo polyol, and fumed silica (SiO2) via a free radical polymerization method for anti-cancer drug delivery. Structural, morphological, and mechanical analyses were conducted using FT-IR spectroscopy, scanning electron microscopy, transmission electron microscopy, and rheological techniques. The effect of SiO2 concentration on mechanical strength, swelling ratios, morphological, and drug delivery behavior was investigated. The incorporation of SiO2 nanoparticles in hydrogels resulted in a significant enhancement in its properties. MTT assay of human embryonic kidney (HEK-293) and human colon (HCT116) cancer cell lines was conducted for up to 48 h to evaluate biocompatibility and cytotoxicity. These studies confirmed the biocompatible nature of nanocomposite hydrogels. Cisplatin-loaded nanocomposite hydrogels exhibit sustained release as compared to free cisplatin at pH 4.0 an...

The electronic and communication devices such as mobile, laptop, and radio ease our day-to-day life. However, these devices emit harmful radiation, which affects human health and the environment. Therefore, to prevent such radiation-based pollution and provide a safer working environment, viable and promising EMI shielding materials have been investigated. Keeping this in mind, the present work reports the relatively low-temperature synthesis of bismuth-doped barium ferrite (BaBixFe12−xO19, Bi-BFO) nanoparticles and their nanocomposite via sol–gel and in situ emulsion polymerization approaches for their application in EMI shielding material. The influence of Bi-doping on phase purity, morphology, structure, and thermal behavior has been explored. The EMI shielding properties of these materials have been investigated in the X-band (8.2–12.4 GHz) region. The composite (Bi-BFO:PT = 2:1 Bi-BFO/PTh-21) with 1 mm thickness exhibited maximum shielding effectiveness (SE) of − 47.12 dB in the X-band region. The high shielding activity is mainly due to the efficient complementarities between the magnetic and dielectric loss. The doping of Bi in barium ferrite results in the increase in electrical polarization that led to the high dielectric loss, causing higher absorption of electromagnetic (EM) waves. These studies suggest that the nanocomposite may find its scope as an excellent microwave absorber for a wide frequency region.

Oleo polymer coatings provide a paradigm shift in traditional corrosion control. Herein, the present work provides new insight on solventless Tung oil Polyetheramide-Cerium oxide (UTOPETA-CeO2) nan...

Present study reports a facile synthesis of surface-active antimicrobial hyperbranched polyurethane coatings using oleo-ethers of boric acid (BA) as branching and biocidal moiety (BHPU). The antimicrobial branching center was synthesized via polycondensation reaction of BA and vegetable oil-based diol. The structural characterization of synthesized BHPU and its linear counterpart was investigated using Fourier-transform infrared (FTIR) and nuclear magnetic resonance (1H, 13C, and 11B NMR) spectroscopy techniques. The cured coatings were examined by physico-mechanical, thermogravimetric (TG) analysis and differential scanning calorimetry (DSC). The antimicrobial behavior of these polymers against Gram-positive and Gram-negative bacteria was carried out by well diffusion technique. The appearance of zone of inhibition (ZOI) in case of BHPU confirmed its antimicrobial activity, which arisen due to the presence of cationic moiety in its structure. These investigations showed that the utilization of oleo-ethers of BA as branching agent in synthesis of BHPU coatings induced prominent effect on its physico-mechanical, thermal, and biocidal properties. In addition, soil burial study for 210 days was conducted on BHPU film to confirm its contact-killing mechanism against soil-borne bacteria. These results suggest the potential scope of BHPU in various applications such as long-term antimicrobial surface-active coatings for medical devices, packaging industry, paints, etc. Keywords: Boric acid, Hyperbranched, Polyurethane, Antimicrobial coating, Sustainable polymers

Tung oil monoglyceride (TMG), 4,4′-diaminodiphenylsulfone modified (DDS-TO-alkyd) polypyrrole enveloped cerium oxide (PPy-PSCeO2) nanofiller dispersed alkyd nanocomposites (alk-DDS-PPy-PSCeO2-x) were synthesized using pyromellitic dianhydride through an eco-friendly, solvent-less and in situ approach. Structural elucidation was carried out using Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance (1H, 13C NMR), X-ray diffraction (XRD), and thermogravimetric analysis (TGA) techniques while morphological studies were performed using a scanning electron microscope (SEM/EDX), dynamic light scattering (DLS) and optical micrographs. Physico-chemical and physico-mechanical studies were tested to ASTM standards with a hydrophobic study measured by CA values. Further, the anticorrosive performance of the plain alkyd (alk-Pl) and alk-DDS-PPy-PSCeO2-x nanocomposite-coatings were experimentally studied using potentiodynamic polarization (PDP), electrochemical impedance spectroscopy (EIS) and salt spray studies (SST). These studies revealed that nanocomposite (alk-DDS-PPy-PSCeO2-1.5) coatings synthesized by the green and solvent-less approach exhibit higher physico-mechanical properties, hydrophobicity, adhesion and superior corrosion protective performance under acidic and saline environments in comparison to reported oleo-alkyds and other oleo-polymer nanocomposite coatings. The proposed oleo-alkyd nanocomposite-coatings are found to be ecologically reliable and thermally more stable and can be safely used up to 213 °C.

Herein, a facile route was employed for the construction of novel dual-functional boronated (hybrid) hyperbranched polyurethane composite (HPUC) coatings using covalently functionalized reduced graphene oxide (FRGO) as chain extender and reinforcing agent. The FRGO exhibited excellent compatibility with the boronated HPU matrix that resulted in the chemical, structural and surface transformation of FRGO-HPUC coatings. The electrochemical corrosion studies were employed to confirm the protective performance of these composite coatings. The presence of electron deficient centres (tri-coordinated B) and electron rich FRGO restricted the diffusion of electrons through the coating network, which altered the mechanism of corrosion protection. In addition, the antimicrobial surface activity of these composites were investigated to ascertain their permanent contact killing properties.

Waterborne polyurethanes (WPUs), owing to their environmental friendliness and non-flammability, are considered as a green class of materials for a wide spectrum of applications, like adhesives, co...

The chemically oxidized gum arabic was prepared and used as a naturally derived nontoxic and pH-responsive cross-linker to develop smart polyvinyl alcohol (PVA)-based hydrogels for the first time. The formulated hydrogels exhibited high mechanical properties, good porosity, and pH sensitivity, which facilitated their application as promising biomaterials for sustained delivery of folic acid. Further, the synthesized cross-linked PVA hydrogels displayed no cytotoxicity toward the human embryonic kidney cell line and exhibited higher blood compatibility. The hydrolytic degradation study confirmed their biodegradable nature. While the sustained delivery along with photoprotective properties of these hydrogels confirmed their multifunctional characteristics, these results suggest that these hydrogels may act as an efficient photoprotective material and find their application in the field of drug delivery.

Surface functionalized tri-metallic strontium magnesium ferrite (Sr0.3Mg0.7Fe2O4, SMF) nanoparticles were synthesized by using facile solvent less green oleo polyol method. Various analytical techniques (XRD, XPS, FT-IR, TEM, SEM, BET, and VSM) were used for the investigation of the crystal lattice, surface functionalization, morphology, surface area, and magnetic properties of these nanoparticles. SEM and TEM analysis revealed that the nanoparticles exhibit mesoporous morphology with cubic structure. These mesoporous nanoparticles have been exploited for the removal of toxic organic pollutant (Congo red, CR) from the aqueous solution. Detailed investigations on the adsorption of CR dye by these nanoparticles have been conducted via the rate kinetics study using various adsorption isotherms (Freundlich, Langmuir, Temkin, etc.). These studies revealed that the mesoporous SMF nanoparticles with the high surface area (21.85 m2g−1), have exhibited superior adsorption capacity (>90% within 30 min) and fast separation ability under the influence of external magnetic field along with good recyclability (∼93%). The adsorption analysis of magnetic SMF revealed pseudo-second order dye removal kinetics and follow Freundlich isotherms. These properties of magnetic SMF nanocubes provide an extra edge over other such reported systems and may find its potential as a cost-effective magnetic adsorbent for water treatment application.

Barium ferrite encapsulated polythiophene (BaFe12O19/PTh) nanocomposite has been synthesized to analyse electromagnetic interference (EMI) shielding. The morphological analysis of the synthesized composites has been investigated by scanning electron microscopy (SEM), which confirmed the encapsulation of BaFe12O19 nanoparticles by PTh forming a core-shell structure. Highest loading of BaFe12O19 in composite (NC-100 i.e. BaFe12O19:PTh = 1:1) exhibits excellent magnetic properties with a magnetic moment and coercivity of 25.78 emu/gm and 2.5 kOe, respectively. Microwave shielding behaviour of the nanocomposite samples has been tested in X-band region by vector network analyser. Highest −43.27 dB shielding effectiveness at 11.65 GHz has been obtained in NC-100 composite. The excellent shielding effectiveness is due to the synergistic effect of dielectric and magnetic loss of the nanocomposite. These results suggest that the BaFe12O19/PTh nanocomposite (NC-100) exhibited superior EMI shielding properties and find wider application as low cost, high performance, lightweight microwave absorbing material.

Inhibition of electrochemical and microbial corrosions is one of the prominent importance in both industrial and environmental applications. Therefore, we have designed a sustainable surface-active bi-functional (antimicrobial/anticorrosive) polyurethane nanocomposite (PUC) coating by means of synergistic effects of π-π interaction and in situ incorporation of graphene oxide (GO) for the first time. The PUC was synthesized using Pongamia oil, acrylic acid (to induce π-π interaction), GO (biocidal and reinforcing agent), and toluene diisocyanate (TDI) via one-pot addition polymerization. These interactions improved GO distribution, which influenced the structure and segmental dispersion within the PUC network. Further, it was observed that the properties (physical, mechanical, thermal, barrier, and adhesion) of the synthesized PUC coating were significantly improved. The electrochemical studies confirmed that upon addition of small amount of GO (0.5 wt.%) the anticorrosive behavior of PU nanocomposite coating was increased, exhibiting high corrosion potential (Ecorr= -0.179 V), low corrosion current density (Icorr = 2.3 × 10−11 A. cm-2), and enhanced impedance modulus at low frequency (|Z|0.01 Hz = 3.6 × 1010 Ω cm2) even after 21 days of immersion (5% NaCl solution). Besides, the surface activity of the PUC coating was confirmed by its strong contact-killing effect against Gram-positive and Gram-negative bacteria. Based on these results, present work provides a facile route towards the development of high-performance dual-functional coatings that may find a wider scope of applications in various industries like maritime, food, fuel and healthcare.

A waterborne polyesteramide (WBPEA) and its nanocomposites (WBPEA–RGO) were synthesized using soya oil, diethanol amine, phthalic anhydride and RGO nanoparticles. Ethanolic solutions of RGO nanoparticles were dispersed in WBPEA via sonication (WBPEA–RGO) and simultaneously both (WBPEA) and (WBPEA–RGO-x) were cured with 80 phr poly(melamine-co-formaldehyde) isobutylated solution (PMF). Their coatings (WBPEA–PMF-80 and WBPEA–PMF-80–RGO-x) were formulated on finally polished carbon steel strips. The structural elucidation of these materials was performed by FT-IR and NMR spectroscopic analysis. The physico-chemical, physico-mechanical, thermal and anticorrosive properties of these coatings were investigated, which revealed that the nanocomposite coatings possess remarkably good physico-mechanical [impact resistance (150 lb per in.), scratch resistance (11.5 kg), bend tests (flexibility retained up to 1/8 inch)] properties. The nanocomposite coatings show far superior anticorrosive performance (impedance = 107 ohm cm2 and phase angle = 85.6°) in comparison to those of WBPEA–PMF-80 (impedance = 106 ohm cm2 and phase angle = 82°) and other such reported coatings.

Graphene oxide (GO) reinforced Polyvinyl chloride (PVC)-Waterborne Castor Alkyd (WCA) nanocomposites (PVC/WCA/GO) films were processed through solution blending technique. TGA showed that the thermal stability of PVC/WCA/GO-0.5 films was better than that of PVC/WCA blend film. With incorporation of 0.5 wt.% GO, the tensile strength and elastic modulus of the blend nanocomposite have significantly improved by about 260% and 185%, respectively, compared with neat polymer. The physico-mechanical properties of these films suggest that the PVC/WCA/GO nanocomposite films may have a potential scope for their application in packaging industries. The results are supported by characterizations like FTIR, XRD, TEM and FESEM.

Nanocomposite hydrogels have found a wide scope in regenerative medicine, tissue engineering, and smart drug delivery applications. The present study reports the formulations of biocompatible nanocomposite hydrogel films using carboxymethyl cellulose-hydroxyethyl cellulose-acrylonitrile-linseed oil polyol (CHAP) plain hydrogel and Na-montmorillonite (NaMMT) dispersed CHAP nanocomposite hydrogel films (NaCHAP) using solution blending technique. The structural, morphological, and mechanical properties of resultant nanocomposite hydrogel films were further investigated to analyze the effects of polyol and NaMMT on the characteristic properties. The synergistic effect of polyol and nanofillers on the mechanical strength and sustained drug-release behavior of the resultant hydrogel films was studied, which revealed that the increased cross-link density of hydrogels enhanced the elastic modulus (up to 99%) and improved the drug retention time (up to 72 h at both pHs 7.4 and 4.0). The release rate of cisplatin in nanocomposite hydrogel films was found to be higher in CHAP-1 (83 and 69%) and CHAP-3 (79 and 64%) than NaCHAP-3 (77 and 57%) and NaCHAP-4 (73 and 54%) at both pHs 4.0 and 7.4, respectively. These data confirmed that the release rate of cisplatin in nanocomposite hydrogel films was pH-responsive and increased with decrease of pH. All nanocomposite hydrogel films have exhibited excellent pH sensitivity under buffer solution of various pHs (1.0, 4.0, 7.4, and 9.0). The in vitro biocompatibility and cytotoxicity tests of these films were also conducted using 3-(4,5-dimethylthiazole-2-yl-2,5-diphenyl tetrazolium bromide) assay of human embryonic kidney (HEK-293) and human breast cancer (MCF-7) cell lines up to 48 h, which shows their biocompatible nature. However, cisplatin-loaded nanocomposite hydrogel films effectively inhibited the growth of human breast MCF-7 cancer cells. These studies suggested that the proposed nanocomposite hydrogel films have shown promising application in therapeutics, especially for anticancer-targeted drug delivery.

Pemphigus Vulgaris (PV) is a life-threatening autoimmune disease manifested with blisters in the skin and mucosa and caused by autoantibodies against adhesion protein desmoglein-3 (Dsg3) expressed in epithelial membrane linings of these tissues. Despite many studies, the pathogenesis of PV remains incompletely understood. Recently we have shown Dsg3 plays a role in regulating the yes-associated protein (YAP), a co-transcription factor and mechanical sensor, and constraining reactive oxygen species (ROS). This study investigated the effect of PV sera as well as the anti-Dsg3 antibody AK23 on these molecules. We detected elevated YAP steady-state protein levels in PV cells surrounding blisters and perilesional regions and in keratinocytes treated with PV sera and AK23 with concomitant transient ROS overproduction. Cells treated with hydrogen peroxide also exhibited augmented nuclear YAP accompanied by reduction of Dsg3 and α-catenin, a negative regulator of YAP. As expected, transfection of α-catenin-GFP plasmid rendered YAP export from the nucleus evoked by hydrogen peroxide. In addition, suppression of total YAP was observed in hydrogen peroxide treated cells exposed to antioxidants with enhanced cell-cell adhesion being confirmed by decreased fragmentation in the dispase assay compared to hydrogen peroxide treatment alone. On the other hand, the expression of exogenous YAP disrupted intercellular junction assembly. In contrast, YAP depletion resulted in an inverse effect with augmented expression of junction assembly proteins, including Dsg3 and α-catenin capable of abolishing the effect of AK23 on Dsg3 expression. Finally, inhibition of other kinase pathways, including p38MAPK, also demonstrated suppression of YAP induced by hydrogen peroxide. Furthermore, antioxidant treatment of keratinocytes suppressed PV sera-induced total YAP accumulation. In conclusion, this study suggests that oxidative stress coupled with YAP dysregulation attributes to PV blistering, implying antioxidants may be beneficial in the treatment of PV.

Biodegradable and biocompatible hydrogels are a fairly imperative class of biomaterials, which find applications for drug delivery. The blending of natural biopolymers and synthetic polymers has introduced exceptional characteristics in hydrogels for diverse biomedical applications. Here, we report a novel class of pH responsive, hydrophobically modified chitosan based hydrogels using methylmethacrylate (MMA) and sustainable polyol. The polyol derivatized hydrogels were characterized using FT-IR spectroscopy, thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and scanning electron microscopy (SEM). The biodegradability studies were carried out in soil and water. The in vitro equilibrium swelling behavior in different buffer solutions of pH values (4 and 7.3), including some physiological solutions were also evaluated. The potential of these hydrogels in drug delivery was demonstrated by preliminary biocompatibility assessment in different human sera for 24 hours. No significant changes in the values of various components present in sera before and after test procedures were found.

The frequent use of electrical equipment and devices has raised a serious threat to the environment and society in the form of electromagnetic interference (EMI), which not only decreases the competency of instruments but also affects the human health badly. Therefore, to reduce the effect of EMI, materials with high shielding effectiveness (SE) need to be designed. Conducting polymers (CPs) such as polyaniline, polypyrrole, polythiophene, etc., provide high conductivity and dielectric properties and are found to be promising for EMI shielding applications. Further, to enhance its SE, composites based on CPs have been widely studied. In view of this, the present chapter highlights the recent developments in CP composites in EMI shielding. The synthesis and properties of such materials are also discussed in detail. Further, the future scope of CP-based EMI shielding materials has also been discussed in detail.

The waterborne soya alkyd (WSA) and its RGO dispersed nanocomposites (WSA-RGO) were synthesized via ex situ polymerization using a solvent-less green approach. The soya oil monoglyceride was used as precursor for waterborne alkyd. The synergistic effect of nanofillers and poly melamine coformaldehyde isobutylated solution modified organic matrix (WSA) on physicomechanical and corrosion inhibition of these coatings on finally polished carbon steel (CS) was investigated. Their physicochemical, physicomechanical, and thermal properties were analyzed using standard protocols. The electrochemical corrosion measurements of these coatings were performed using Potentiodynamic Polarization and Electrochemical Impedance Spectroscopy. The aforementioned studies revealed that the nanocomposite coatings exhibit promising corrosion protection performance which is evident from the icorr, Ecorr, impedance and phase angle values of coatings (i.e., icorr 7.736 × 10–9 Acm–2, Ecorr −0.191 V, impedance ∼107 Ω cm2, and phase a...

In near future, bio-based polymer coatings are expected to gradually replace the fossil oil based coating materials. However, extensive application of bio-based polymer is still a challenge because of its several limitations. The use of organic-inorganic hybrid cross linker is one of the interesting strategies used for the processing of highly crosslinked polymer coatings with improved mechanical and anticorrosive performance. Thus present work reports the preparation of organic-inorganic hybrid (OIH) cross linker using melamine formaldehyde (MF) and 3 isocynatopropyl triethoxy silane (IPTES). The structural characterization was carried out using various spectroscopic techniques, which provide ample evidence in favor of MF/IPTES cured alkyd formation. The impact of OIH cross linker on various properties like physico-mechanical, adhesion, thermal stability and anticorrosive properties was investigated systematically. The enhancement in aforementioned properties could be explained in terms of synergistic effect of s-triazine ring of melamine formaldehyde and IPTES.

The conversion of micro lignin to lignin nanoparticles (LNP) and their application in engineering and technology are potential steps towards global sustainability because lignin is obtained from industrial and agricultural waste and can be used in green chemistry. In the present study, we report the high-yield synthesis of lignin nanoparticles in different media, i.e., castor oil (CO), ethylene glycol (EG) and water (W) and evaluate their effect on the size and morphology of the LNP. The syntheses of LNP cover 9 out of 12 of the green chemistry principles; the synthesis was carried out via acid precipitation in a polyol medium, which acts as a stabilizing agent. From the results of the TEM, DLS, and SEM studies, it was observed that ≈15–20 nm LNP were successfully formed and spherical morphologies were observed when EG and CO were used as solvents. Furthermore, the anticorrosive behaviour of these nanoparticles was evaluated; the LNP acted as anticorrosive nanofillers for the protection of carbon steel (CS) in stringent corrosive conditions and was dispersed in an epoxy matrix to formulate epoxy nanocomposite coatings. Physicomechanical and electrochemical impedance spectroscopy (EIS) studies suggest that LNP-dispersed epoxy coatings potentially protect the underlying materials and show better protection as compared to the bare epoxy coatings.

Globular structured oleo alkyds possess low viscosity, good fluidity and play important role in the generation of volatile organic compound (VOC) free paints and coatings. Soya oil (SO), an abundant, inexpensive, renewable, and sustainable is one of the examples of such oleo alkyd precursor that meets the requirement of green chemistry. Present work reports the synthesis of hyperbranched soya alkyd based nanocomposite coatings and their corrosion inhibition efficiency. Hyperbranched alkyd (HBA) was synthesized using SO, pentaerythritol and phthalic anhydride. The magnetite (Fe3O4) nanoparticles were dispersed via sonication in butylated melamine formaldehyde (BMF) modified HBA (HBA-BMF) to formulate the nanocomposite (HBA-BMF-Fe3O4) anticorrosive coatings. The ASTM methods were used to evaluate structural, morphological, physico-mechanical, thermal, electrochemical and anticorrosive properties of these coatings. The HBA has a globular structure with the good degree of branching (DOB = 0.69). HBA-BMF and H...

With the endless efforts in the development of polymer composite materials, conducting polymer reinforced in polyurethane (CP/PU) composites are gaining tremendous attention of scientific community in the past few years. Conducting polymers as a reinforcement, offers exceptional properties when it combines with the thermoplastic polyurethane matrix. In view of this, we critically highlight the development of different types of conducting polymers reinforced in polyurethane composites, with a detailed discussion on their method of synthesis and various characterizations techniques. Furthermore, the promising applications of CP/PU composites have also been discussed. Finally, we attempted to assemble the existing challenges and the possible future perspectives.

In the present study, preparation, characterization and coating properties of plant oils based organic-inorganic hybrid materials [OIHM] are described. Polyols from Castor oil [CO], Linseed oil [LO] and tetraethoxyorthosilane [TEOS] serve as organic and inorganic constituents, respectively. OIHM are prepared by “hydrolysis-condensation” reactions. The hydroxyl groups of polyols condensed with TEOS, forming silica anchored polyol based OIHM which on addition reaction with isocyanate formed polyurethane hybrids [COHM-PU and LPOHM-PU]. In FTIR spectra of OIHM, absorption bands at 800 cm −1 (Si O Si sym str) and 1090.0 cm −1 (Si-O-Si assym str) confirmed the formation of nano silica, that occurred as unagglomerated and spherical particles as observed in TEM micrographs of OIHM. Thermogravimetric analysis showed the onset of degradation at 220 °C–225 °C. OIHM showed moderate to good antibacterial behavior against E.coli and S.aureus . OIHM coatings showed good corrosion rate and inhibition efficiency in 3.5 wt% NaOH, 3.5 wt% HCl and performed well in salt fog environment. The corrosion rate and IE% values for COHM-PU were found to be 1.534 × 10 −2 mm/yr and 94.208%, and 9.923 × 10 −3 mm/yr and 95.062% for LPOHM-PU, in 3.5 wt% NaOH for 0.5 mol loading of TEOS. In 3.5 wt% HCl, corrosion rate was 9.78 × 10 −3 mm/year for COHM-PU with IE% value as 91.90% and 7.98 × 10 −3 mm/year for LPOHM-PU with IE% value as 93.44%. OIHM were developed via a synergistic approach wherein plant polyols provide matrix for the production of SiO 2 ; the latter act as reinforcements improving the performance properties in hybrid polyurethane. OIHM may serve as platform chemicals for numerous industrial products such as paints and coatings.

Nano-sized CuO particles were prepared insitu via “one-pot, solvent-less” microwave-induced synthesis, by environmentally benign polyol process using polyol obtained from Linseed oil by (non-aqueous) condensation reaction, for the first time. Linseed polyol acts as solvent, base matrix providing functional groups, and stabilizer; the reaction is devoid of any additive, catalyst or solvent. In the prepared nanocomposites [LPE-CuO], CuO nanoparticles shaped somewhat like rods, assembled themselves in a “T-fashion”. The antifungal effects of synthesized particles were investigated against four clinical isolates of different Candida species. Results showed that the synthesized compound LPE-0.06 was found to be most effective, followed by LPE-0.05 and LPE-0.04. The rapid actions of the synthesized compounds on fungal cells suggested membrane-located targets. We investigated the effect of MIC90 values of these compounds on H+-ATPase mediated proton pumping by different Candida species. In the absence of glucose, the mean inhibition rate of H+ extrusion caused by MIC of LP was 28.09%, LPE: 33.04%, CuAc: 36.86%, LPE-0.04: 58.54%, LPE-0.05: 69.82% and LPE-0.06: 78.07%, respectively. Antifungal mechanism of action suggested that the synthesized compounds exert their antifungal activity by targeting H+-ATPase mediated proton pumping. Inhibition of H+-ATPase activity leads to intracellular acidification and consequently cell death. Results obtained in this study indicated strong antifungal activity of synthesized compounds against all the Candida species and suggest that the inhibition of fungal H+ ATPase is responsible for the antifungal activity of the test compounds. LPE-CuO can be employed as antifungal polyester and polyurethane coatings. The present work is consistent with the Principles (Principle 1,2,3,4,5,6,7,8, 12) of Green Chemistry.

Mechanical stability, surface hydrophobicity, and thermal stability of anticorrosive polymeric coatings play a significant role in technological and industrial fields. In view of this, the present study demonstrates the design of transparent organic–inorganic hybrid nanocomposite coatings with improved mechanical strength and barrier properties. Herein, a suspension was formulated containing in situ grown titania (–O–Ti–O–) from titanium isopropoxide (TIP), diglycidyl ethers of bisphenol-A (DGEBA), and polyamide (PA). TIP simultaneously acts as a condensation agent, bridging agent (–O–Ti–O), as well as an inorganic surface modifier to epoxy resin and increases the water contact angle due to topographical improvement via optimum cross-linked surface density. The surface, morphological, thermal, and electrochemical techniques highlight broader application areas for these hybrid polymeric materials. The lowest Icorr value of 2.5211 × 10−10 for DGE–TiO2–PA hybrid coatings compared to those of DGE–PA (2.1029 × 10−7), CS (8.9131 × 10−5), and other reported coating systems in saline (3.5 and 5 weight% NaCl) environments projects DGE–TiO2–PA as a potential anticorrosive coating material.

Modification of Hyaluronic acid (HA) with Sodium metaperiodate (NaIO4) results in the formation of oxidized HA (OHA). OHA containing multiple aldehyde groups can easily react with the materials having amino functionality via formation of Schiff base linkage, resulting in the formation of OHA based hydrogel scaffolds. These hydrogels have recently attracted considerable attention as scaffolds for tissue engineering (TE) applications. Thus, the aim of the present review is to give an overview on OHA based hydrogels as scaffolds and their potential application in the field of TE along with the method of synthesis and important properties of OHA.

Nanocomposite coatings with synergistic properties hold a potential in long-term corrosion protection for carbon steel. Polydiphenylamine (PDPA) and vanadium pentoxide (V2O5) have rarely been used ...

Ethelynediamine modified graphene oxide (MGO) covalently functionalized with poly(p-phenylenediamine) (MGO-PPPDA) nanofiller was synthesized and characterized by Fourier transform infrared spectroscopy (FTIR), X-Ray diffraction analysis (XRD), and Transmission Electron Microscopy (TEM). Their composites were formulated using safflower oil polyurethane (PU) viz; MGO/PU, PPPDA/PU, and MGO-PPPDA/PU through 0.5 wt.% dispersion of these (MGO, PPPDA and MGO-PPPDA) nanofillers via ultra-sonication. Their coatings were prepared on carbon steel. The corrosion protective performance of these coatings were investigated under harsh acidic environments (5 wt.% HCl and H2SO4) with the help of potentiodynamic polarization (PDP), electrochemical impedance spectroscopy (EIS) and salt spray techniques. The results revealed that the synergistic effect of both MGO and PPPDA within a single PU matrix remarkably enhances the corrosion protection ability of MGO-PPPDA/PU than those of MGO/PU and PPPDA/PU nanocomposite coatings.

To overcome the shortcomings of petro-based polymer coatings, researchers have intensified research efforts on the development of eco-friendly and sustainable polymer coatings. It may help in reducing the burden on fossil fuel, which is expected to deplete by near future. Thus, here we report the In-situ formulation of solvent-less hydrophobic bi-functional ceria doped Tung Oil Polyesteramide nanocomposite coatings. The physico-chemical, physico-mechanical, structural, corrosion protective and flame-retardancy performance of these hybrid inorganic-organic nanofillers dispersed Tung Oil polyesteramide nanocomposite coatings were investigated using standard methods i.e. Fourier-transform infrared spectroscopy (FTIR), nuclear magnetic resonance (NMR), x-ray diffraction (XRD), thermal gravimetric analysis (TGA), scanning electron microscopy (SEM), transmission electron microscopy (TEM), vertical burning test (VBT), potentiodynamic polarisation (PDP), electrochemical impedance spectroscopy (EIS) and salt-spray test. The studies revealed that the prepared nanocomposite coatings exhibit excellent adhesion, hydrophobicity, negligible water uptake, superior corrosion protection and flame retardancy behaviour than those of other such reported oleo polymer coating systems. The coatings can be safely used up to 200 °C.

High-performance vegetable oil based organic–inorganic bio hybrid materials are of great interest in the current scenario, as the utilization of vegetable oil meets the seventh principle out of the 12 Principles of Green Chemistry that contributes to sustainability in chemistry due to their universal availability, inherent biodegradability, low price, and superb environmental credentials. Here, we report the synthesis of transparent organic–inorganic bio hybrid coatings by tailoring the properties of both linseed oil and 3 isocynatopropyl triethoxysilane (IPTES) using the sol–gel technique. Such materials combine the advantages of both the phases that are usually not compatible within the same material (robustness and homogeneity, mechanical strength, flexibility, optical transparency, hydrophobicity, and anticorrosive properties). The structure elucidation, particle size, and morphology of the synthesized OIH polymers were done by FT-IR, 1H NMR, 13C NMR, 29Si NMR, and electron microscopy techniques (TEM ...

Environment friendly soy polyester urethane nanocomposite coating materials were prepared by dispersing TiO2 and Ce-TiO2 nanoparticles in a 3-isocyanatopropyltriethoxysilane (IPTES) modified soy oil (SO) polyester urethane triethoxysilane (PEUTES) matrix via a sonication technique. Fourier Transform Infrared Spectroscopy (FT-IR), 1H and 13C Nuclear Magnetic Resonance (NMR) spectroscopy, Scanning Electron Microscopy (SEM), Energy-Dispersive X-ray spectroscopy (EDX), X-ray Diffraction (XRD), Transmission Electron Microscopy (TEM), UV-visible spectroscopy (UV) were employed to characterize the synthesized coating materials. The anticorrosion ability of nanocomposites and that of PEUTES coatings on carbon steel (CS) in 3.5 wt% NaCl solution was investigated using potentiodynamic polarization (PDP), Electrochemical Impedance Spectroscopy (EIS) techniques and a salt mist test. The effects of dispersion of nano TiO2 and Ce-TiO2 fillers in PEUTES matrices on the hydrophobic, physico-mechanical, thermal and anticorrosive properties were also studied. The TiO2 and Ce-TiO2 nanofiller dispersed soy polyester urethane nanocomposite coatings have exhibited far superior corrosion resistance properties than those of other such reported systems. These studies revealed the presence of nanofiller in polyester urethane matrix, induces strong barrier and locking effects at the coating–metal interface. The higher impedance value (≈108 Ω) and lower corrosion rate (7.8518 × 10−6 mpy) confirm the superior protection ability of the nanocomposite.

The projected fossil fuel deposits depletion by near future and detrimental effects of petroleum products on environment has led to the development of volatile organic compound (VOC) free low molecular weight sustainable polymers, with promising applications in field of inks, adhesives, paints, and coatings. In view of this, present study reports synthesis, characterization, and anticorrosive performance of SMG-PU and modified SMG-PU through in situ formed silica networks (SMG-PU-TEOS) OIH polymer nanocomposite coatings on CS. The size of ∼30 nm silica nanonetworks were formed within SMG-PU on addition of TEOS, inducing thermal stability, hydrophobic, improved physicomechanical and corrosion resistant properties to polymer nanocomposite coatings. The corrosion protective performance of these coatings in 5% NaCl (salt mist test), 3.5% NaCl, and 3.5% HCl solutions revealed very lower Icorr values (3.8891 × 10–10 A cm–2 and 6.8756 × 10–9 A cm–2) as compared to SMG-PU (1.8159 × 10–8 A cm–2 and 9.1396 × 10–7 A...

Novel copper(II) nanocoordination complexes [LCuCl]Cl C1, [LCu(SCN)]SCN C2, and [LCu(NO3)]NO3C3 capped by bis-benzimidazole diamide ligand N1,N5-bis{(1H-benzo[d]imidazole-2-yl)methyl}glutarimide L were synthesized and characterized by spectroscopic methods viz. transmission electron microscopy (5–100 nm), dynamic light scattering, elemental analysis, EPR, and infrared spectroscopy. These complexes were also tested for their ability to inhibit nitric oxide release during culture. Lipopolysaccharide-induced superoxide production decreased most significantly for complex C2. Nanocoordination complex C2 also showed the most significant in vitro cytotoxicity against HeLa human cervical cancer cells, MCF-7 breast cancer cells, and U-87 glioblastoma cells, ranging from 50 μg ml−1 to 500 μg ml−1. In vivo study revealed an increase in body weight (11.5 g) for the tumour control groups, whereas in the case of the mouse groups treated with test sample C3, the difference in body weight as compared to the control was approximately 4.7 g. In further studies, it decreased to 2.2 g and 0.6 g in the case of mouse groups treated with nanocoordination complexes C1 and C2, respectively. The mean mouse survival time was 21 days, which increased to 100, 120, and 170 days for C3, C1, and C2, respectively.

The synergistic contributions of nanofillers and polymer matrix induce remarkable properties in nanocomposite hydrogels. Present article reports the facile synthesis of biocompatible nanocomposite hydrogels using microporous multi wall carbon nanotubes (MWCNTs) dispersed chitosan (CH)-Acrylonitrile (AN), N,N'-methylenebisacrylamide (MBAAm) and linseed polyol through solution blending method. Polyol and N,N'-methylenebisacrylamide (MBAAm) was used as the crosslinking agent. The structural characterization and formation of highly crosslinked network with dendrimer morphology was confirmed by FT-IR and scanning electron microscope (SEM) analysis. In addition, transmission electron microscope (TEM) was employed to visualize the size and proper dispersion of MWCNT in the polymer matrices. The strong mechanical strength exhibited by these hydrogel films was confirmed by the tensile strength analysis. The dispersion of the conductive nanofillers, like MWCNTs has significantly enhanced the strength, which revealed unique characteristics of these hydrogel films. The high swelling capacity and sustained expansion of hydrogel films were confirmed in the buffer solutions of pH4 and 7.4. The biodegradability of these films was estimated by hydrolytic and soil burial tests. The biocompatibility test was conducted on Human Embryonic Kidney (HEK-293) cell line, which confirmed the non-toxic and biocompatible nature of these films. Incorporation of carbon nanotubes (MWCNTs) in the polymer matrix enhanced the film forming properties, high modulus and tensile strength, swelling ability, biodegradable and biocompatibility. These properties can be finely tuned through the variation of MWCNT concentrations, as a result these nanostructure hydrogel films have potential scope for their diverse applications in the field of tissue engineering.

The work presents the physico-mechanical properties and potentiodynamic polarization measurements studies of linseed oil based polyurethane/tetraethoxyorthosilane [LPU/TEOS] hybrid and polyurethane/tetraethoxyorthosilane/fumed silica NC [LPU/TEOS/FS] hybrid nanocomposite coatings. The best coating performance was obtained by the inclusion of 2 wt% FS in 2-LPU/TEOS hybrid. 2-LPU/TEOS/FS produced glossy, transparent, flexibility retentive, scratch-resistant and impact resistant coatings at ambient temperature relative to LPU/TEOS coatings. 2-LPU/TEOS/FS showed good scratch hardness (5.5 kg), impact resistance (250 lb/in.), flexibility (1/8 in.) as investigated by standard methods with corrosion rate obtained as 3.567 × 10−4 mm/year and 4.05 × 10−4 mm/year and inhibition efficiency as 99.816% and 99.710% in 3.5% NaOH and 3.5% HCl, respectively.

The present article reports the synthesis and corrosion protection performance of polyorthotoluidine (POT) nanoparticles dispersed castor oil polyurethane (COPU) nanocomposite coatings in acid and saline environments. The structure of POT/COPU was confirmed by FTIR and UV-visible spectroscopic techniques. The nanostructure of the pristine POT nanoparticles and those in the composite was characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). The physico-mechanical properties were analyzed using standard methods. The corrosion protective performance was evaluated by weight loss, potentiodynamic polarization and electrochemical impedance spectroscopy in an acid medium. While in the saline environment the corrosion protective performance was investigated in a salt mist chamber using a 5% NaCl solution for 30 days. The morphological behavior of the corroded and un-corroded coated specimen was investigated by SEM studies. The stipulated acid and saline corrosion mechanism was also discussed.

Nano conducting polymer (CP) dispersed polymer hydrophobic coatings are considered to be a new generation coating system. They have promising applications in the area of anticorrosive coatings and have proved to be an effective alternative to the toxic phosphate–chromate based coatings. In view of this, for the first time, we report here the effect of microwave (MW) irradiation on various properties of polythiophene (PTh) and compare with conventionally polymerised nano PTh (cPTh). The effect of MW irradiation on the morphology, size, solubility and electrical properties are investigated with the help of TEM, SEM, CV and four probe conductivity measurements. The synthesis has been carried out in aqueous medium, as it is green, renewable, environmentally friendly and free from harmful VOCs. The nano PTh dispersed epoxy-polyamide (PA) nanocomposite coatings are developed on carbon steel (CS). The mPTh–epoxy-PA shows superior flexibility, gloss, adhesion, impact and scratch resistance properties than those of the cPTh–epoxy-PA nanocomposite coatings. The salt spray test and potentiodynamic polarization (PDP) studies on these coatings reveal that the mPTh–epoxy-PA nanocomposite coatings show superior anticorrosive properties (Ecorr/Icorr: −0.30301 V/3.1587 × 10−9 A cm−2) than cPTh–epoxy-PA (−0.32138 V/1.1003 × 10−8 A cm−2) and epoxy-PA (−0.45505 V/9.3862 × 10−7 A cm−2) coatings. The morphology of corroded and uncorroded coatings are analysed by SEM/EDAX. The promising physico-mechanical properties and corrosion protection performance of mPTh–epoxy-PA nanocomposite coatings highlighted the potential of MW techniques for the synthesis of CPs.

Electromagnetic interference (EMI) is one of the main causes for the failure of electronic devices working in close vicinity of EM field induced by the neighboring electronic device. Therefore, we report a facile synthesis of barium ferrite (BaFe12O19) nanoparticles via sol-gel technique for efficient EMI shielding application. These nanoparticles were annealed at 400 °C, 700 °C, and 850 °C to investigate the effect of temperature on shielding efficiency and morphology of BaFe12O19 nanoparticles. The structure, morphology, phase purity, magnetism, and shielding effectiveness were analyzed using Fourier-transform infrared (FT-IR) spectroscopy, x-ray diffraction (XRD), electron microscopy (SEM and TEM), vibrating sample magnetometer (VSM) and vector network analyzer, respectively. These studies suggest that BaFe12O19 nanoparticles annealed at 850 °C exhibit crystalline pure phase hexagonal structure with the high magnetic moment (31.32 emu g−1) and coercivity (2.7 kOe). The total shielding effectiveness of the same was found to be −17.57 dB at 11.58 GHz, which is much higher than those of earlier reported studies.

Some preliminary investigations on “green” preparation, morphology and antibacterial behavior of Linseed polyol nanocomposite [LMPOL] for antibacterial polyurethane coatings are summarised. Nanocomposite is prepared in situ with Linseed polyol [LP] matrix as organic and Copper acetate as inorganic constituent by “solventless one-pot” chemical reaction. The presence of characteristic absorption bands in FTIR spectra confirmed the formation of LMPOL. TEM analysis showed the presence of nano-sized metal oxide in LMPOL. LMPOL showed good antibacterial behavior against E. coli and S. aureus . The interactions between LMPOL and bacterial surfaces lead to good antibacterial efficacy, suggesting membrane disruption based cell death. LMPOL may serve as an excellent starting material for antibacterial polyurethane coating. The approach is an excellent example for the preparation of “green” polyol from “green” resource en route Green Chemistry for protective polyurethane coatings.

Discovery of hydrogels has resulted in developing competent controlled-release drug delivery systems. Present study describes the synthesis and characterization of novel pH responsive hydrogels of chitosan, hydroxyl ethyl cellulose (HEC) and polyol prepared by physical blending of the three components in different ratios. Vegetable oil derived polyol seems to act as a filler and cross linking agent. The synthesized hydrogels were characterized using FT-IR spectroscopy, thermo gravimetric analysis (TGA), Optical microscopy and scanning electron microscopy (SEM). Equilibrium swelling behavior of hydrogels in water and different buffers with pH values (2, 4, 7.3, and 8) indicated the sustained expansion of the films in different pH solutions.

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.