Search

Chloromethylated polysulfone (CMPSF) microfiltration membrane were first prepared by using immersion-precipitation phase transformation method, and then CMPSF membrane was modified into aminated PSF membrane (AMPSF membrane). A surface-initiating system of-N[H.sub.2]/[S.sub.2][O.sub.8.sup.2-] was constituted at the interface between AMPSF membrane and a aqueous solution, in which monomer dimethylaminoethyl methacrylate (DMAEMA) and initiator ammonium persulfate were dissolved. The graft polymerization of DMAEMA was successfully realized on AMPSF membrane, resulting in the grafted membrane PSF-g-PDMAEMA. And then quaternization modification of the grafted membrane PSF-g-PDMAEMA was performed, resulting in the cationic microfiltration membrane of PSF-g-QPDMAEMA. The isothermal adsorption experiments of PSF-g-QPDMAEMA membrane for two acid dyes, reactive brilliant red (RBR), and reactive light yellow (RLY), were carried out, and the permeation experiments were also conducted. The experimental results show that PSF-g-QPDMAEMA membrane has strong adsorption ability for acid dyes by right of the electrostatic interaction between the quaternary ammonium cations on the surface of PSF-g-QPDMAEMA membrane and the sulfonate anions in the molecules of acid dyes as well as by right of cation-[pi] interaction between the quaternary ammonium cations on PSF-g-QPDMAEMA membrane and the aromatic rings in the molecules of acid dyes. PSF-g-QPDMAEMA membrane displays excellent rejection and removing performance for acid dyes in water., INTRODUCTION Organic dyes are familiar pollutants in wastewater, which could generate a great deal of toxic substances. Their source can be tracked down from textile industries as well as other [...]

In order to make polysulfone (PSF) microfiltration membrane to have the rejection selectivity, the microfiltration membrane of chloromethylated polysulfone (CMPSF) was first modified into aminated membrane (AMPSF membrane), and the functional monomer dimethylaminoethyl methacrylate (DMAEMA) was graft-polymerized on PSF membrane by the initiating of the surface-initiating system of – NH2/S2O82-, resulting in the grafted microfiltration membrane of PSF-g-PDMAEMA. And then PSF-g-PDMAEMA membrane was transformed into the quaternized (Q) membrane, PSF-g-QPDMAEMA membrane. The experimental results show that the graft-polymerization of DMAEMA can be carried out smoothly, and the cationic membrane, PSF-g-QPDMAEMA membrane, is successfully gotten. Both above two membranes are functional membranes. [ABSTRACT FROM AUTHOR]

Chopped carbon fibers with different dispersion types (colony type and uniform type) and area densities were inserted at sandwich beams, consisting of a PVC foam core covered with two glass fiber/epoxy composite face sheets. The effects of this reinforcement on the interfacial bonding between PVC foam core and glass fiber face sheets were evaluated. Their mechanical properties were measured by three‐point‐bending and Charpy impact tests. Their structures after mechanical failure were observed by scanning electron microscopy. Compared with the beam without interfacial reinforcement, the bending strength, energy absorption, and impact strength after interfacial reinforcement using 20 g/m2 uniform chopped fibers increased by up to 109%, 184%, and 47%, respectively, surpassing those of other chopped fiber mats. The weight percentage of carbon fibers/sandwich structure was less than 1%, so the chopped carbon fiber interleave had both cost effectiveness and outstanding structural performance. The improvement of interlayer toughness can mainly be attributed to the fiber bridging structure and the interlayer strength. POLYM. COMPOS., 40:E449–E455, 2019. © 2018 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

The rapid detection of nitroaromatic explosive in low concentration sample or complex matrices is of importance. In this paper, 2,4,6-trinitrotoluene (TNT) molecularly imprinted polyvinyl alcohol microspheres, MIP-CPVA, are synthesized in inverse suspension system using TNT as template, PVA as functional polymer, and glutaraldehyde as cross-linker. The MIP-CPVA possesses high affinity, specific recognition ability, and excellent selectivity towards TNT. The saturated adsorption capacity could reach to 10.62 mg g−1, and the selectivity coefficients relative to DNT is 12.44. In additional, MIP-CPVA can be used as the column packing of gas chromatograph to separate and detect nitroaromatic, and the result is very satisfactory. [ABSTRACT FROM PUBLISHER]

An anion-imprinted material with high performance for recognizing chromate anions was prepared by adopting the novel surface-molecular imprinting technique put forward by our research group previously. Functional macromolecule polyethyleneimine (PEI) was first grafted on the surfaces of micron-sized silica gel particles in the manner of 'grafting to,' forming the grafted particle PEI/SiO2. Afterwards, the ion imprinting was carried out towards the macromolecule PEI grafted on the surface of the silica gel particles by using [image omitted] ion as a template and ethylene glycol diglycidyl ether (EGGE) as crosslinking agent, and chromate ion-surface imprinted material IIP-PEI/SiO2 was obtained. The binding characteristic of IIP-PEI/SiO2 for [image omitted] ion was studied with both static and dynamic methods. The experimental results show that IIP-PEI/SiO2 has excellent binding affinity and high recognition selectivity for chromate anion. Before imprinting, the grafted particles PEI/SiO2 have similar adsorption capacities for both chromate anion and phosphate anion that was used as a contrast substance. However, after imprinting, the binding capacities of IIP-PEI/SiO2 towards phosphate anion decrease remarkably, whereas the binding capacity of IIP-PEI/SiO2 for chromate anion still remains higher, leading to a very high selectivity coefficient (12.23) of IIP-PEI/SiO2 for [image omitted] ion with respect to the [image omitted] ion. IIP-PEI/SiO2 is a separation material with high performance. [ABSTRACT FROM AUTHOR]

Alumina/polyurethane composites were prepared via in situ polymerization and used as thermal interface materials (TIMs). The surface of alumina particles was modified using polydopamine (PDA) and then evaluated via Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TG), and Raman spectroscopy (Raman). Scanning electron microscope (SEM) images showed that PDA-Al 2 O 3 has better dispersion in a polyurethane (PU) matrix than Al 2 O 3 . Compared with pure PU, the 30 wt% PDA-Al 2 O 3 /PU had 95% more Young's modulus, 128% more tensile strength, and 76% more elongation at break than the pure PU. Dynamic mechanical analysis (DMA) results showed that the storage modulus of the 30 wt% PDA-Al 2 O 3 /PU composite improved, and the glass transition temperature (Tg) shifted to higher temperatures. The thermal conductivity of the 30 wt% PDA-Al 2 O 3 /PU composite increased by 138%. Therefore, the results showed that the prepared PDA-coated alumina can simultaneously improve both the mechanical properties and thermal conductivity of PU., Competing Interests: The authors declare no conflict of interest.