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To develop efficient coatings from a biobased vegetable oil (castor oil, CO) towards the elimination of fossil resources as well as the prevention of the impact of microorganisms on the surface of maritime vessels, coatings of biorenewable and biodegradable nonisocyanate polyurethane (NIPU) and nonisocyanate polyurethane nanocomposite (NIPU-F) were formed. The biorenewable precursor, CO, was transformed into the cyclic carbonate (CO–CC) substrate to form NIPU upon reaction with a long chain aliphatic diamine (1,12-diaminododecane) via a facile one pot reaction followed by film casting to recover the NIPU film. Furthermore, the protocol to form NIPU-F was executed by incorporation of synthesised amine-functionalised silica coated iron oxide nanoparticles (Fe3O4@SiO2–NH2) into the NIPU matrix via covalent bond formation. Subsequently, the physicochemical (1H and 13C NMR, FTIR, XRD and VSM), thermal (TGA and DSC) and morphological (SEM, optical microscopy and EDAX) characterization of NIPU and NIPU-F films was performed along with water contact angle and biodegradation studies. The results highlighted that the synthesized NIPU shows the highest Tg value of 55 °C with the average static water contact angle of 44°. The hydrophilic properties of above polymeric samples are identified as appropriate for applications in coatings towards antifouling, antibacterial and anticorrosion protection on submerged solid surfaces. As such the results from studies on NIPU and NIPU-F coatings indicated their remarkable resistance against E. coli bacteria with reduction rates of 99.7 and 88.7% respectively. Indeed, the settlements of algae like Spirulina platensis (S. platensis) on NIPU and NIPU-F diminished significantly by 71.2% and 52.9%, respectively, as compared to that of the control sample. Furthermore, the electrochemical impedance spectroscopy (EIS) studies suggested that when immersed in electrolyte solution for over a period of 24 h, the anticorrosion performance of both NIPU and NIPU-F attained a comparable level, with impedance magnitudes ‖Z‖ of ∼ 1.6 × 103 and ∼1.7 × 103 Ohm, respectively. Herein, the demonstration of EIS studies in 3.5 wt% NaCl and inhibition studies against microorganisms in marine environments for NIPU and NIPU-F paves new routes for applying such coatings in a practical environment. [ABSTRACT FROM AUTHOR]

Push--pull organic molecules have aroused wide interest in photochemistry and photophysics research communities. In this report, we present the synthesis, characterisation, photophysical and nonlinear optical property studies of a new organic fluorophore (AA2) with a unique push--pull molecular configuration: acceptor--p-bridge--donor--p-bridge--acceptor (A--π--D--π--A) constituted with phenothiazine as the donor moiety. A thorough investigation to validate its structure was undertaken through ¹H, 13C NMR and MALDI-TOF mass spectrometry. A variety of studies were undertaken to unravel its optical properties both experimentally and theoretically. A systematic investigation probing its optical absorption and emission characteristics revealed its strong dependence on solvent polarity, which confirmed the crucial role played by the intra molecular charge transfer (ICT) process emerging from its unique molecular and electronic structure. Such a strong structure--property correlation could be exploited for various optoelectronic applications, which triggered us to explore AA2 for photonics applications driven by nonlinear optical responses. Our nonlinear optical investigations confirmed strong excited state absorption at 532 nm when excited in the nanosecond regime using the Z-scan technique. This opened up yet another avenue of exploring it for optical limiting applications. The estimated optical limiting threshold for an AA2 molecule is about 0.98 J cm-2, which proved its high suitability for such photonics applications while outperforming many other organic fluorophores and benchmarked nanostructures under similar experimental evaluation. This is one of the very first reports on phenothiazine with an A--π--D--π--A configuration accompanied by excellent nonlinear optical properties. [ABSTRACT FROM AUTHOR]

By reactions of both catalyzed and non‐catalyzed pathway, we attempt to show that the synthetic route of non‐isocyanate polyurethanes (NIPU) is developed quite recently. The advancement of sustainable, bio‐renewable, impermeable and moisture‐insensitive NIPU has started to contribute its role in academia and industry. In case of NIPU formulation, polycondensation of dicarbonate with diamine precursors as well as waste‐free polyaddition of multifunctional cyclic carbonates with diamines via ring‐opening polymerization. Obviously, since the hydroxyl groups (both primary and secondary hydroxyl group) arisen in NIPU is employed to reveal fairly different attributes compared to trivial polyurethanes (PU). The advantage of NIPU comprises of the role of carbon dioxide and renewable feedstock, while various cyclic carbonates obtained to react with diamine substrates to incorporate desired physicochemical and mechanical properties. Indeed, NIPU are noted to be non‐toxic, biodegradable and exhibit remarkable properties. In this review, we account the imperative strategies employed in developing essential sustainable NIPU have been discussed in detail. [ABSTRACT FROM AUTHOR]

The reaction of the cyclotriphosphazene [N.sub.3][P.sub.3][Cl.sub.5][O-[C.sub.6] [H.sub.4]-p-[C.sub.6][H.sub.4]-p-CH = C[H.sub.2]] (2) with 10 equiv of N-methylhydrazine proceeds in a regio-specific manner to afford the multi-functional hydrazide [N.sub.3][P.sub.3][[N(Me)[NH.sub.2].sup.5]][O-[C.sub.6][H.sub.4]-p-[C.sub.6] [H.sub.4]-p-CH = C[H.sub.2]] (3). Condensation of 3 with o-hydroxy benzaldehyde or pyridine-2-carboxaldehyde affords the corresponding hydrazones [N.sub.3][P.sub.3][[N(Me)N = CH-[C.sub.6] [H.sub.4]-o-OH].sub.5][O-[C.sub.6][H.sub.4]-p-[C.sub.6][H.sub.4]-p-CH = C[H.sub.2]] (4) and [N.sub.3][P.sub.3][[N(Me)N = CH-[C.sub.6][H.sub.4]N].sub.5][O-[C.sub.6][H.sub.4]-p-[C.sub.6][H.sub.4]-p-CH = C[H.sub.2]] (5), respectively. These hydrazones can be homopolymerized to afford polymers 6 and 7 containing multi-site coordinating cyclophosphazenes as pendant groups. Key words: cyclophosphazene, hydrazone, pendant polymers, hybrid polymers, polymeric ligands.

Polymer composite membranes composed of crosslinked sulfonated poly(vinyl alcohol) (SPVA) and fly ash (FA) were prepared via solution casting method. The physicochemical properties of these electrolyte membranes were studied in detail. SEM and XRD results provide evidence for the successful incorporation of fly ash into the SPVA matrix. As such SPVA polymer loaded with 20 wt.% of fly ash exhibited the ionic conductivity of 0.016 S. cm−1, whereas pristine membrane occurred to show 0.008 S. cm−1. The substantial results achieved with the organic-inorganic composites have been demonstrated and reported membranes can be a feasible electrolyte for fuel cell applications. [ABSTRACT FROM AUTHOR]

A novel luminescent hybrid inorganic–organic molecular assembly was synthesised by the condensation of hexakis cyclotriphosphazene hydrazide (CTP-Hyd) with six units of 10-octyl-10H-phenothiazine-3-carbaldehyde (R-PTZ-CHO) for the first time. In particular, synthesis of a new precursor, an inorganic heterocycle, CTP-Hyd, has been developed to append PTZ units on the periphery of the thermally stable CTP ring via condensation. The luminescent hybrid material prepared by the convergent approach was well characterized at each step using a plethora of techniques like FT-IR and multi-nuclear NMR including 1H, 13C and 31P as well as HRMS/MALDI-TOF data. Further, the photophysical properties of the synthesised hybrid material were investigated by UV-visible absorption, steady state and time resolved photoluminescence spectroscopy. The synthesised hybrid molecule shows extraordinary solvent compatibility and shows tunable emission in the yellow–green region. A relatively large Stokes shift of 82 nm was observed with varying solvent polarity owing to the charge transfer nature of the electronic transition in the hybrid molecule. The thermal stability and electrochemical properties of key substrates and products were studied using thermal gravimetric analysis (TGA) and cyclic voltammetry studies respectively. The high Td value of 326 °C inferred that the hybrid CTP-PTZ exhibited superior thermal stability. This study shows important insight into the understanding of the hybrid material properties for possible application in the areas of optoelectronics and bio-imaging. [ABSTRACT FROM AUTHOR]

The cyclophosphazene hydrazide gem-[N.sub.3][P.sub.3][Ph.sub.2][[N(Me)N[H.sub.20]].sub.4 is reacted with o-hydroxybenzaldehyde to produce the multisite coordination ligand gem-[N.sub.3][P.sub.3][Ph.sub.2][[N(Me)N[double bond]CH[C.sub.6][H.sub.4]-2-OH].sub.4] (L[H.sub.4]). The latter has reacted with copper(II) slats in order to produce a novel tetranuclear copper assembly that contains 15 contiguous inorganic rings.

Research has been conducted on phosphorus supported multisite coordinating ligand. The authors describe the preparation of this compound via condensation of phosphorus tris hydrazide with o-hydroxybenzaldehyde.

The composite polymer electrolyte membranes were prepared from sulfonated poly (ether sulfone) (SPES), silicotungstic acid (STA) and fly ash (FA). Post sulfonation process was adopted to synthesize SPES using sulphuric and chlorosulfonic acid. The prepared electrolyte membranes were examined by water uptake capacity, swelling ratio, ion-exchange ability, proton conductivity, thermal stability and electrochemical performance for evaluating the pertinence of these membranes in fuel cell applications. As such the pristine membrane restricts with the proton conductivity of 0.042 S cm−1 at 30 °C and 0.060 S cm−1 at 90 °C while the polymer composite membrane, SP-STA-FA-10 reveals the maximum conductivity of 0.054 S cm−1 at 30 °C and 0.073 S cm−1 at 90 °C. It also exhibits good thermal stability than that of the pure membrane. The membrane electrode assemblies (MEAs) have been successfully developed from SPES as well as SP-STA-FA-10 membranes and their electrochemical performance were studied the wide range of current density. Herein, the composite membranes derived from SPES, STA and FA can be viable candidates for fuel cell applications. [ABSTRACT FROM AUTHOR]

Abstract: Novel 36- 6 and 42- 7 membered cyclophosphazene-containing macrocycles were obtained by [2+2] condensation reactions of N3P3(O2C12H8)2[–O–C6H4–p-CHO]2 3 with PhP(O)[N(Me)NH2]2 4 or 1,6-diaminohexane 5. [Copyright &y& Elsevier]

Biodegradable trifunctional polyol, polycaprolactone triol (PCL) has been chosen as major component (~77 wt%) to develop polyurethane (PU) foam with promising physicochemical and mechanical properties upon optimization of essential components such as surfactant, catalysts and diisocyanate reagent as well as variation of isocyanate index and chain extender in the presence of trace volume of water. To accomplish the optimization of PU foam formulation by one-shot method, a set of free raised foam samples were obtained by solvent free method at ambient condition. In addition to the physicochemical characterization of these foams molded in paper cup, non-trivial characteristic parameters like density, hardness, cushioning energy for walking (CEw) and running (CEr), cushioning factor for walking (CFw) and running (CFr) as well as compression set values were measured and correlated against the morphology of each foam sample, particularly to identify the suitable one, which exhibits the recommended physical parameters to use as semi-flexible insole in footwear. Optimization of biodegradable polyurethane foam formulation is achieved using major ratio of polycaprolactone triol (~77 wt%) with 1, 6 - hexamethylene diisocyanate and other reactive components via one-shot process to afford the semi-flexible foam in paper cup, free from solvent. The correlation of cell morphology against characteristic physical data supports to develop semi-flexible foam with appropriate crosslinking density, high cushioning energy and low compression set as shock absorbing and damping insole material towards green shoe. Unlabelled Image • This article on biodegradable polyurethane (PU) foam aims to reduce non-biodegradable polymeric waste disposal in environment • Polycaprolactone triol (PCL) is used exclusively as polyol via one-shot process to obtain foams by solvent free method in cup • PCL (~ 77 wt.%) loaded in major ratio with aliphatic diisocyanate and other additives tends to afford unprecedented PU foams • Semi-flexible, low density, high cushioning energy foam for damping shoe insole was established in footwear upon optimization [ABSTRACT FROM AUTHOR]

ABSTRACT Herein, a new hybrid inorganic–organic ligand was designed and synthesized to form a series of transition metal (II) complexes as potential substrate towards cytotoxicity studies. The inorganic heterocycle, cyclotriphosphazene (N3P3Cl6, CTP) was chosen as the core unit to synthesize geminal hydrazone Schiff bases as multisite coordination ligand via substitution of six reactive chlorine. Herein, CTP was substituted by nucleophilic reaction at six chlorine atoms that exist on three phosphorus (V) centers of CTP with salicylaldehyde to form hexakis salicylaldehyde derivative. Further, salicylic hydrazide tethered with terminal amine group was condensed with above hexakis salicylaldehyde derivative of CTP at ratio of 1:6 afforded SBCTP ligand. Indeed, a series of M (II) complexes (M = Co, Ni, Mn, Cu and Zn) were obtained from SBCTP ligand with characteristic functional groups to manifest the cytotoxic activity, in order to venture as the active anticancer agent in pharmaceutics. Despite the Schiff base of aromatic rings tend to exhibit inherent cytotoxic properties, the complementary influence of CTP appended with two consecutive salicylic units in SBCTP found to show unique properties. In particular, metal (II) complexes via imine bonds of SBCTP oriented from CTP ring found to reveal essential properties to treat cancerous cells. The above ligand and prospective metal complexes were investigated individually for the cytotoxic activity with normal and cancerous cells at five different concentrations, with/without addition of the above samples into MTT assay. Structural characterization of above samples was conducted by multinuclear NMR, 1H, 13C, and 31P as well as ESI, HRMS, FTIR, EDS, and TGA data. [ABSTRACT FROM AUTHOR]

The article presents an abstract of an author response to technical commentary, the full text of which is available on the journal's web site and regards the paper "The Silicate-Mediated Formose Reaction: Bottom-Up Synthesis of Sugar Silicates," by J.B. Lambert et al. in the February 19, 2010 issue.

Mononuclear divalent metal complexes of 13-membered macrocycle were evaluated under in vitro condition as intercalators with efficient antimicrobial performance. Cu(II) complex show potential cytotoxic activity towards tumor cell lines and performs effectively. [Display omitted] • Synthesis of tetraaza macrocyclic metal complexes. • Efficient interaction of DNA with Cu(II) complex. • Potential antimicrobial effect against pathogens. • Effective cytotoxicity against human cancer cell lines. We report a new tetraaza macrocyclic Knoevenagel Schiff base as the 13-membered ligand developed by non-template route via condensation of 3-(cinnamyl)-pentane-2,4-dione with two equivalent of 4-aminoantipyrine as pendant group prior to its execution for Knoevenagel condensation with o-phenylenediamine. The above type of conjugate macrocyclic ligand tends to employ as a potential tetradentate ligand, which generated a seies of macrocyclic metal complexes (1 – 4) with Cu(II), Co(II), Ni(II) and Zn(II) metal ions. Herein, the macrocyclic ligand and its metal complexes were characterized by the spectral and analytical methods including UV– vis , FT-IR, 13C and 1H NMR, ESI-MS, EPR, microanalytical and magnetic moment values. The above set of data tend to suggest that synthesized metal complexes exist in square planar geometry, whereas high molar conductance values supported about the distribution of complexes in ionic nature. Indeed, cyclic voltammetry and optical absorption titration as well as hydrodynamic experiments and docking analysis data were used to identiy the way of binding of these metal complexes with calf thymus deoxyribonucleic acid as intercalation type. Further, DNA damage study was conducted by gel electrophoresis. Moreover, these complexes were studied for antimicrobial screening under in vitro condition against a set of microorganisms via broth dilution technique. It was noted that all the complexes occurred to reveal better activity as compared to macrocyclic Schiff base ligand. Also, the cancer cell lines including cervical, epithelioma, human breast and cell line of normal human dermal fibroblast were chosen to assess for cytotoxic effect with above samples. [ABSTRACT FROM AUTHOR]

Iron oxide nanoparticles (Fe 3 O 4 NPs) and functional inorganic cyclotriphosphazene Schiff's base (SBCTP) are hybridized to afford conjugate NPs, Fe 3 O 4 @SBCTP NPs for cytotoxicity studies with normal and cancerous cells at five different concentrations, with/without addition of the drug in MTT assay. • Fe 3 O 4 NPs and cyclophosphazene Schiff base (SBCTP) hybridized to form Fe 3 O 4 @SBCTP NPs Fe 3 O 4 @SBCTP NPs show the complementary role of anticancer agents, Fe 3 O 4 NPs and SBCTP. • Conjugate NPs, Fe 3 O 4 NPs and SBCTP studied for cytotoxicity on normal/cancerous cells. • Conjugate NPs show synergic effect towards cancerous cells compared to individual NPs. It is our objective to hybridize iron oxide nanoparticles with functional inorganic substrate to afford the potential conjugate nanoparticles for cytotoxicity studies. Magnetic iron oxide nanoparticles (Fe 3 O 4 NPs), tethered with amine functional groups on its surface has been chosen as template to condense with the inorganic heterocyclic Schiff's base (SBCTP) as a pendant group to afford conjugate nanoparticles. SBCTP, a non-geminal heterobifunctional substrate is synthesized by the substitution of five arms of Schiff's base and one unit of aromatic aldehyde on hexachlorocyclotriphosphazene (HCCP). Despite the above two substrates exhibiting inherent drug properties, their mutual complementary role with case of Fe 3 O 4 @SBCTP NPs is investigated upon simple condensation of Schiff's base units of SBCTP substrate on the surface of Fe 3 O 4 NPs. Synthesis and characterization of the originally designed conjugate nanoparticles, Fe 3 O 4 @SBCTP NPs tends to exhibit potential anti-cancer properties to treat cancerous cells. As such the prospective hybrid product, Fe 3 O 4 @SBCTP NPs and its precursors, Fe 3 O 4 NPs and SBCTP have been investigated separately for the cytotoxic activity with normal and cancerous cells at five different concentrations, with/without addition of the drug in MTT assay. Structural characterization of the above samples was deduced by data collected from multinuclear NMR (1H, 13C and 31P), solid state NMR, ESI mass, HR MS, FT-IR, UV– vis , XRD, FESEM, HRTEM, EDX, TGA and VSM at ambient temperature. [ABSTRACT FROM AUTHOR]