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Fullerene adducts have attracted attention in a variety of applications including organic optoelectronic devices. In this regard, we have designed a covalently linked donor-acceptor dyad comprising a fluorobenzothiadiazole-thiophene (BTF

3D printing involves the use of photopolymerizable resins, which are toxic and typically have incompatible properties with materials such as polystyrene (PS), which present limitations for biomedical applications. We present a method to dramatically improve the poor adhesion between the PS insulative layer on 3D printed Microelectrode Array (MEA) substrates by functionalizing the resin surface with polydopamine (PDA), a mussel-inspired surface chemistry derivative. A commercial 3D printing prepolymer resin, FormLabs Clear (FLC), was printed using a digital light processing (DLP) printer and then surface functionalized with PDA by alkali-induced aqueous immersion deposition and self-polymerization. It was observed that the adhesion of the PS to FLC was improved due to the precision emanating from the DLP method and further improved after the functionalization of DLP printed substrates with PDA at 1, 12, and 24 h time intervals. The adhesion of PS was evaluated through scotch tape peel testing and instron measurements of planar substrates and incubation testing with qualitative analysis of printed culture wells. The composition and topology of the samples were studied to understand how the properties of the surface change after PDA functionalization and how this contributes to the overall improvement in PS adhesion. Furthermore, the surface energies at each PDA deposition time were calculated from contact angle studies as it related to adhesion. Finally, biocompatibility assays of the newly modified surfaces were performed using mouse cardiac cells (HL-1) to demonstrate the biocompatibility of the PDA functionalization process. PDA surface functionalization of 3D DLP printed FLC resin resulted in a dramatic improvement of thin film PS adhesion and proved to be a biocompatible solution for improving additive manufacturing processes to realize biosensors such as

1,2-Bis{(3,5-dimethylpyrazol-1-yl)methyl}benzene (L) reacts with [Cu(OAc)2] and C6H5COOH, 4-OH-C6H4COOH, 2-Cl-C6H4COOH and (3,5-NO2)2-C6H3COOH to afford the copper complexes [Cu2(C6H5COO)4(L)2] (1), [Cu2(4-OH-C6H4COO)4(L)2] (2), [Cu2(2-Cl-C6H4COO)4(L)2]n (3) and [Cu{(3,5-NO2)2-C6H3COO}2L]n (4) which are characterised by IR, mass spectrometry, elemental analyses, and X-ray crystallography. The structural data revealed two geometries that are adopted by the complexes: (i) paddle wheel in 1, 2·7H2O, 3 and (ii) regular chains in 3 and 4. Magnetic studies show strong antiferromagnetic couplings in the paddle wheel complexes and a weak antiferromagnetic coupling in the monometallic chain one. Catalysis studies performed with these complexes (1–4) showed that they initiate ring opening polymerization (ROP) of e-caprolactone (e-CL) under solvent-free conditions and D,L-lactide in toluene at elevated temperatures. Polycaprolactone (PCL) and poly(D,L-lactide) (PLA) obtained from the polymerization reactions are of low molecular weights (858 for PCL and 602 Da for PLA for initiator 1) and polydispersity indices (typically 2.16 for PCL and 1.64 for PLA with 1 as the initiator). End group analysis of the polymers, determined by MALDI-ToF MS, indicates that the polymers have benzoate, hydroxyl, methoxy and cyclic end groups.

Stimulus-responsive polymers have been used in improving the efficacy of medical diagnostics through different approaches including enhancing the contrast in imaging techniques and promoting the molecular recognition in diagnostic assays. This review overviews the mechanisms of stimulus-responsive polymers in response to external stimuli including temperature, pH, ion, light, etc. The applications of responsive polymers in magnetic resonance imaging, capture and purification of biomolecules through protein-ligand recognition and lab-on-a-chip technology are discussed.

Olefin bonds participate in co-reaction with the benzoxazine functionality of the monomer and is appeared as one of the strategies to affect the crosslink density of a polybenzoxazine network. In general, the double bond incorporation in starting material is usually catalysed by expensive, rare earth metals affecting the sustainability of the reaction. The natural abundance of feedstocks with inherent double bonds, may be a powerful platform for the development of novel greener structures, thus holds inspiring potential and applicability in polymers. Here, we report the design, synthesis and characterisation of biobased non-halogen flame retardant consisting of naturally occurring phenols, eugenol (E) and cardanol (C). The presence of covalently linked phosphazene (P) core allowed synthesis of hexa-functional flame retardant molecules, abbreviated as EP and CP. The chemical structures of the synthesised EP and CP was confirmed by Fourier transform infrared (FTIR), nuclear magnetic resonance (1H, 13C, 31P NMR) and single crystal XRD (only in the case of EP). Their polymerisation with cardanol sourced tri-oxazine benzoxazine monomer, C-trisapm, was followed by FTIR, NMR and DSC studies. The thermal stability and flame retardant properties of the hybrid phosphazene-benzoxazine copolymers was determined by thermogravimetry analysis (TGA), limiting oxygen index (LOI), vertical burning and smoke density analyses. SEM images of the char residues of the polymers with or without addition of reactive phosphazene molecules confirmed the intumescent flame retarding mechanism. Current work highlights the utility of sustainable origin non-halogen flame retardant (FR) molecules and their utility in polybenzoxazine chemistry.

We report on the preparation of hexa-functional cardanol (renewable phenolic compound) benzoxazine with a phosphazene core (CPN) for use as a greener eco-friendly halogen-free flame retardant reactive additive for the formation of sustainable polyphosphazene polybenzoxazine networks for flame resistant applications. The structure and purity of the monomer was confirmed by Fourier transform infrared (FTIR), nuclear magnetic resonance (1H-, 13C-, 31P NMR) and gel permeation chromatography studies. The CPN monomer showed good compatibility with benzoxazine monomer (CPN0) as suggested by the cocuring studies. The thermal properties of the copolymer can be directly tuned by altering the composition of the monomer blend. The occurrence of phosphazene–phosphazane thermal rearrangement is also suggested for the thermal behavior (thermogravimetry analysis) at higher loading of CPN in the monomer feed ratio. An improvement in mechanical properties of the copolymer with increase in glass transition temperature was c...

3,5-Dimethylpyrazole (L), reacts with [Cu(OAc)2] or [Zn(OAc)2]; and either C6H5COOH, 4-OH–C6H5COOH, 3,5-NO2–C6H5COOH or 2-Cl–C6H5COOH to afford the corresponding metal complexes: [Cu(C6H5COO)2(L)2] (1), [Cu(2-Cl–C6H4COO)2(L)2] (2), [Cu(3,5-NO2–C6H3COO)2(L)2] (3), [Cu(4-OH–C6H4COO)2(L)2] (4), [Zn(C6H5COO)2(L)2] (5), [Zn(2-Cl–C6H4COO)2(L)2] (6), [Zn(3,5-NO2–C6H3COO)2(L)2] (7), [Zn(4-OH–C6H4COO)2(L)2] (8). The diamagnetic zinc complexes were characterized by IR, NMR spectroscopy and elemental analysis; while the paramagnetic copper complexes were only characterized by IR spectroscopy, elemental analysis and 1 and 2 were further characterized by single crystal X-ray diffraction studies. All eight complexes are very good initiators for the ring opening polymerization (ROP) of e-caprolactone and d , l -lactide at elevated temperatures, under solvent-free conditions and in toluene respectively; producing polycaprolactone (PCL) and poly( d , l -lactide) (PLA) of moderate molecular weights (ca 4757 Da for PCL and 2484 Da for PLA) and narrow polydispersity indices (1.36 for PCL and 1.42 for PLA). The 13C{1H} NMR spectra indicate the stereochemistry of PLA is heterotactic.

A high-yield, solvent-free approach to the synthesis of 1,3,5-trisubstituted pyrazoles is reported. Four compounds, (3,5-di-tert-butyl-1H-pyrazole, (2-(3,5-dimethyl-1H-pyrazol-1-yl)ethanol, 2-(3,5-di-tert-butyl-1H-pyrazol-1-yl)ethanol, 2-(3,5-diphenyl-1H-pyrazol-1-yl)ethanol were readily prepared by solvent-free condensation of the appropriate dike-tone and the respective hydrazine. The crystal structures of the three pyrazolyl-ethanols are typical of N-substituted pyrazoles. All three pyrazolyl compounds show interesting inter-molecular hydrogen bonding. For the 3,5-dimethyl compound the molecules form discrete hydrogen bonded dimers within a unit cell, while for the others the hydrogen bonding is in a head-to-tail arrangement resulting in the formation of chains.

The hydrogen-bonded arene ruthenium metalla-rectangle, [(p-cymene) 2Ru2(OOnOO)(UPy)2]24+ , obtained from 1-(4-oxo-6-undecyl-1,4-dihydropyrimidin-2-yl)-3-(pyridin-4- ylmethyl)urea (UPy) and the dinuclear arene ruthenium clip (p-cymene) 2Ru2(OOnOO)Cl2 (OOnOO = 2,5-dioxido-1,4- benzoquinonato), is investigated by means of solution-phase NMR spectroscopy. Rotating frame nuclear Overhauser effect measurements are used to probe the H- bond network that drives the UPy self-assembly as well as the full rectangular supramolecular system. An effective distance that takes into account both intra-and intermolecular polarization-transfer pathways is utilised for data analysis. The experimental findings are corroborated by DFT calculations of NMR parameters and internuclear distances, thus confirming the formation of a very stable tetranuclear metalla-assembly.

The title compounds (III) and (IV) are readily obtained by solvent-free condensation of the appropriate diketone and hydrazine derivatives.

The bis(pyrazole)zinc(II) benzoate complexes bis(3,5-diphenylpyrazole)zinc(II) benzoate (1), bis(3,5-diphenylpyrazole)zinc(II) 3,5-dinitrobenzoate (2), bis(3,5-diphenylpyrazole)zinc(II) 4-hydroxybenzoate (3), and bis(3,5-di-tert-butylpyrazole)zinc(II) 2-chlorobenzoate (4) were synthesized from the reaction of 3,5-diphenylpyrazole (L1) or 3,5-di-tert-butylpyrazole (L2), zinc(II) acetate and the appropriate benzene carboxylic acid. The molecular structure of complex 2 confirmed that these zinc(II) benzoate complexes adopt a 4-coordinate tetrahedral geometry. All four complexes were screened as catalysts for the copolymerization of carbon dioxide (CO2) and cyclohexene oxide (CHO) and were found to be active for the formation of poly(cyclohexene carbonate) (PCHC) at CO2 pressures as low as 1.0 MPa under solvent-free conditions and without the use of a co-catalyst. At some reaction condition, most of the catalysts produced PCHC with high carbonate content of up to 98% and a good amount of cyclic cyclohexene carbonate (CCHC). The copolymers produced have low to moderate molecular weights (5200–12300 g/mol) and with polydispersity indices that vary from 1.19 to 2.50. Matrix Assisted Laser Desorption/Ionization-Time of Flight Mass Spectra (MALDI-TOF MS) of these copolymers showed they have benzoate and hydroxyl end groups.