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The influences of structure parameters of polyetheramines as clay‐swelling inhibitors in water‐based drilling fluids on the application performances were studied. Interactions of polyetheramines with clays were investigated through elemental analysis (EA), X‐ray diffraction (XRD), and thermogravimetric analysis (TGA). The results showed that lower molecular weight, hydrophobic oxypropylene segment, and plentiful amino group of polyetheramines favored improvement of inhibitive properties, enhancement of adsorption abilities, and expelling interlayer bound waters of clays (as confirmed by cutting rolling test, bentonite inhibition test, EA, XRD, and TGA studies). Simultaneously, the polyetheramines did not produce adverse effect to filtration control of the drilling fluids. In addition, XRD patterns revealed that these polyetheramines could intercalate into interlayer spaces of clays and display a monolayer arrangement. The corresponding basal spacing of clays was correlated only with molecular weight of polyetheramines. The dense loading of polyetheramines in the interlayer of clays was beneficial in improving inhibitive properties. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013

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Nanofibrillated cellulose (NFC) and graphene oxide (GO) with reinforcing and film-forming properties were employed with graphene to develop a novel and thin electric heating membrane with heat dissipation controllability. A negative charge was found on the surface of GO and NFC in aqueous dispersions, which contributed to the homogeneous distribution of the graphene sheets. The membrane had a good laminated structure with three-dimensional interaction between GO and NFC, with embedded graphene sheets. Conductivity was characterized as a function of the amount of graphene, thus giving control over to the heating power by adjusting the ratio of graphene. Subsequent electric heating tests can remove irregularities on the GO and graphene sheet, improving the laminated structure further. The temperature on the surface of the membrane presented an exponential increasing regularity with time. Under the same power density and time, the stabilized temperature rise of membranes was higher when grammage was higher, which was characterized by the linear function of the power density. Low-grammage membranes (1 and 4 g·m−2) also exhibited regular and even stabilized temperature rises. The indicated structure and heating performance of the membrane, as well as the variation induced by Joule heating, would drive its applications.

Along with the electronic products entering people's life, the electromagnetic radiation is becoming a serious problem threatening human health. Consequently, the aim of this paper is fabricating the electromagnetic shielding materials containing carbon fiber (CF), carbon black (CB), poly(vinylidene fluoride) (PVDF) and poly(ethylene terephthalateco-1,4-cylclohexylenedimethylene terephthalate) (PETG). By adjusting CB content, the composite with high electromagnetic interference shielding effectiveness (EMI SE) was achieved. Additionally, the effects of CB on the rheological, dynamic mechanical properties, and electrical resistivity of PVDF/PETG/CF composites were investigated in detail. That CB formed the conductive networks in the PVDF/PETG/CF/CB composite at 5 % of CB and above led to the reduction in electrical resistivity and the augment of the modulus as well as the glass transition temperature of PETG. From the electrical resistivity and storage modulus points of view, the short CF exhibited the better synergistic effect with CB than the long CF did. But the lowest electrical resistivity (0.39 Ω.cm) occurred in the long CF based composites containing 15 % of CB, and its EMI SE is determined to above 30 dB over a frequency of 0.1 to 1500 MHz.