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One of the environmentally friendly methods is the intelligent utilization of natural one-dimensional nanomaterials as carriers to improve the CO2 catalytic performance of MOF materials. This paper reports an efficient composite catalyst preparation using a cheap and readily available magnesium–aluminosilicate nanometer, attapulgite (ATP), as a carrier for MOF materials. Due to its Lewis acidic site and unique alkaline pore structure, ATP exhibits excellent catalytic activity in the coupling reaction of CO2 with epoxy compounds, and its regular one-dimensional nanorod shape has tremendous potential as a carrier compared to other natural minerals. Given the diversity of MOF material types and structures, the design of this UIO-66/ATP nanocomposite catalyst provides both a new pathway for CO2 capture and conversion and a developmental space for the synthesis of such nanocomposites. [ABSTRACT FROM AUTHOR]

In this paper, a cyclic (CuIpz)3·CH3CN (1) precursor and a mixed-valence pentanuclear complex Cu I3 Cu II2 (OH)pz6·CH3CN (2) have been synthesized and structurally characterized by single-crystal X-ray diffraction, where pzH = 4-chloro-3,5-diphenylpyrazole. The excellent catalytic activity of 2 has been demonstrated in the chemical fixation of CO2 into value-added cyclic carbonates, which can be carried out at ambient pressure and room temperature along with ultra-high yield and perfect steric hindrance tolerance. Based on density functional theory (DFT) calculations and comparison with the catalytic performance of 1, it is proposed that the coordinatively unsaturated CuII atoms of 2 are probably the active sites for this catalytic reaction. [ABSTRACT FROM AUTHOR]

Regioselective synthesis of halohydrin esters was achieved by (1) the reaction of acyl halides with epoxides and (2) the rhodium-catalyzed three-component coupling reaction of alkyl halides, carbon monoxide, and epoxides. [ABSTRACT FROM AUTHOR]

One way to improve the sensitivity and throughput of miniaturized biomolecular assays is to integrate microfluidics to enhance the transport efficiency of biomolecules to the reaction sites. Such microfluidic integration requires bonding of a prefabricated microfluidic gasket to an assay surface without destroying its biological activity. In this paper we address the largely unmet challenge to accomplish a proper seal between a microfluidic gasket and a protein surface, with maintained biological activity and without contaminating the surface or blocking the microfluidic channels. We introduce a novel dual cure polymer resin for the formation of microfluidic gaskets that can be room-temperature bonded to a range of substrates using only UVA light. This polymer is the first polymer that features over a month of shelf life between the structure formation and the bonding, moreover the fully cured polymer gaskets feature the following set of properties suitable for microfluidics: high stiffness, which prevents microfluidic channel collapse during handling; very limited absorption of biomolecules; and no significant leaching of uncured monomers. We describe the novel polymer resin and its characteristics, study through FT-IR, and demonstrate its use as microfluidic well-arrays bonded onto protein array slides at room temperature followed by multiplexed immunoassays. The results confirm maintained biological activity and show high repeatability between protein arrays. This new approach for integrating microfluidic gaskets to biofunctionalised surfaces has the potential to improve sample throughput and decrease manufacturing costs for miniaturized biomolecular systems. [ABSTRACT FROM AUTHOR]

This paper reports an effective route for the syntheses of hydroxy carbamates from the reaction of CO2, epoxides and amines catalyzed by a Au/Fe2O3 catalyst. Under the optimized reaction conditions, various hydroxy carbamates were successfully synthesized with 92–98% isolated yields. The catalyst could be reused for several runs without deactivation. A plausible reaction mechanism was proposed by which the hydroxy carbamate was formed through an ammonium carbamate intermediate and the catalyst mainly promoted further nucleophilic addition between the epoxide and ammonium carbamate. [ABSTRACT FROM AUTHOR]

In this paper we present a reusable, chemically inert, multichannel Chip-to-World-Interface (CWI). The concept of this interface is based on a force fit connection similar to the hollow screw connectors known from high-performance liquid chromatography (HPLC) instruments. It allows contamination free connection of up to 100 thermoplastic tubes to microfluidic chips made from various materials e.g., epoxy polymers, glass and polydimethylsiloxane (PDMS). The spacing of the tubes is fixed whereas the outer dimensions of the CWI can be adapted to the microfluidic chip it should be used with. We demonstrate that such a CWI with 100 tubes is pressure-tight up to (at least) 630 kPa (6.3 bar) pressure and the connection easily sustains flow rates above 4 ml min−1. The presented CWI is designed such that the fluid probed in the microfluidic chip is in direct contact only with the tube material and the material from which the microfluidic chip is made. This not only enables fluid transport without dead volume, it also ensures that CWI itself will not be contaminated or contaminate the samples being probed. Using polytetrafluoroethylene (PTFE, Teflon®) tubing we demonstrate that the CWI can even be used with harsh organic solvents such as dichloromethane or dimethylformamide during continuous solvent probing over several hours without damage to the CWI or leakage. This CWI therefore effectively allows using almost all types of organic solvents in microfluidic applications. [ABSTRACT FROM AUTHOR]

In this paper, two bio-based epoxy curing agents were synthesized using rosin acids. The chemical structures of the rosin derivatives were confirmed in detail by 1H NMR, 13C NMR, FT-IR and ESI-MS. The synthesis methods of the rosin-based curing agents, curing behaviors and properties of the cured epoxy resins were studied. Two commercial curing agents, which have similar functionality and structural resemblance to the rosin-based curing agents, were also used in the study for comparison. Compared with the synthesis of petrochemical curing agents, the synthesis of rosin-based curing agents was simpler and more environmentally friendly, and has less strict requirements on reactors and catalysts. Non-isothermal curing of a commercial liquid epoxy was studied using differential scanning calorimetry (DSC). The thermal mechanical properties and thermal stability of the cured epoxy resins were evaluated using dynamic mechanical analysis (DMA) and thermogravimetric analysis (TGA), respectively. Results showed that the curing behaviors of the rosin-based curing agents were similar to those of the commercial curing agents. The epoxies cured by rosin-based curing agents also demonstrated similar thermal mechanical properties and thermal stability to the epoxies cured by commercial curing agent analogs. [ABSTRACT FROM AUTHOR]

Zn3[Co(CN)6] based double metal cyanide complexes are currently used as catalysts for both the ring-opening polymerization of epoxides and the copolymerization of epoxides and CO2. This paper reports an environmentally friendly route for the copolymerization of cyclohexene oxide (CHO) with CO2 using microwave irradiation. The reaction occurred over a faster reaction time (2–30 min) and a much lower pressure (9.7 bar) than conventional methodologies giving a high molecular weight (19.3 kg mol−1) polycarbonate with a higher level of CO2 incorporation (fCO2 = 75%). The catalysts were prepared from an aqueous solution of ZnX2 and K3[Co(CN)6] using tert-butanol and polyethers as complexing agents. All the catalysts were characterized by elemental analysis, ICP-OES, XRD, XPS and IR spectroscopy. The catalysts were found to be highly selective for the copolymer with a high TOF (TOF = 25 177 h−1) values. Unlike conventional synthesis, there was no induction period noticed for the catalyst to initiate copolymerization. The high reactivity and excellent properties of the copolymer might be due to the higher activation of CHO by microwaves due to its high polarizability and higher dielectric constant. [ABSTRACT FROM AUTHOR]

In this paper we describe a highly effective surface modification of SU-8 microparticles, the attachment of appropriate linkers for solid-supported synthesis, and the successful chemical modification of these particles viacontrolled multi-step organic synthesis leading to molecules attached in an unambiguous manner to the support surface. [ABSTRACT FROM AUTHOR]