InstrumentationThermal Analysis. Standard thermal gravimetry experiments were performed on a TA Instruments Q5000IR TGA. Samples were heated in platinum pans from ambient temperature to 600.0°C at 20.0°C/min. A TA Instruments Q1000 Differential Scanning Calorimeter (DSC) was used to evaluate thermal transitions of the (co)polymers. Samples (~ 3-8 mg) were prepared in standard aluminum pans/lids and were first heated from ambient temperature to 160.0°C at a ramp rate of 20.0°C/min. Samples were subsequently cooled to -50.0°C at 25.0°C/min and finally heated to 160.0°C at 20.0°C/min. Glass transition temperatures are reported from the second heating as the mid-point of the heat flow derivative curve. The DSC was calibrated using indium standard (In; melting point, T m, In = 156.6 °C; provided by TA Instruments) according to the manufacturer's recommendation, which includes baseline and temperature calibrations.Additionally, standard thermal gravimetry experiments were performed on a TA Instruments Q5000IR TGA. Samples were heated in platinum pans from ambient temperature to 600.0°C at 20.0°C/min. Raman Microspectroscopy. Raman spectroscopy of thin polymer films were performed using a Renishaw 100 confocal micro-Raman system equipped with a CCD detector. A 632.8 nm HeNe laser was focused to 2 µm spot size with a 50x objective. Raman spectra were acquired using a 60 s integration time. Atomic ForceMicroscopy. A Digital Instruments Dimension 3100 atomic force microscope (AFM) was used in tapping mode to obtain height images of 1000 µm lines of a PGMA 73 -b-PVDMA 174 copolymer spin-coated from solution in CHCl 3 at a concentration of 0.75% wt and annealed under vacuum at 110 °C. The micropattern was made by photolithographic techniques. 1The amplitude set-point and proportional and integral gains were adjusted for each sample assuring optimal image quality. All measurements were done at a scanning rate of 0.5 Hz using silicon nitride cantilevers. An area of 8 µm × 8 µm at the edge of the pattern was initially surveyed in order to obtain a direct comparison of layer thickness values obtained by AFM and by ellipsometry. Then, a 2 µm × 2 µm area on the polymer layer was sampled, which allowed the film's topography and roughness to be examined.

The three-phase hydrodeoxygenation (HDO) of 5-hydroxymethylfurfural (HMF) and hydrogenation of 2,5-dimethylfuran (DMF) were studied over six carbon-supported metal catalysts (Pt, Pd, Ir, Ru, Ni, and Co) using a tubular flow reactor with 1-propanol solvent, at 180°C and 33 bar. By varying the space time in the reactor, the reaction of HMF is shown to be sequential, with HMF reacting first to furfuryl ethers and other partially hydrogenated products, which then form 2,5-dimethylfuran (DMF). Ring-opened products and 2,5dimethyltetrahydrofuran (DMTHF) were produced only from reaction of DMF. Rate constants for the pseudo-first-order sequential reactions were obtained for each of the metals. The selectivities for the reaction of DMF varied with the metal catalyst, with Pd forming primarily DMTHF, Ir forming a mixture of DMTHF and open-ring products, and the other metals forming primarily open-ring products. Catalyst stabilities followed the order Pt ~ Ir > Pd > Ni> Co > Ru. Since the stability order correlated with carbon balances in the product (>93% for Pt; <75% for Ru), deactivation appears to be caused by deposition of humins on the catalyst.

As a positive temperature coefficient of resistivity (PTCR) material, (1−x)BaTiO3–x(Bi0.5Na0.5)TiO3 (BT–BNT, 0.01≤x≤0.08) ceramics without any donor doping were prepared by a conventional solid‐state reaction method. All samples were sintered in an N2 atmosphere at 1340°C, followed by reoxidizing at 800°–1100°C in air. The PTCR characteristics of BT–BNT ceramics were investigated in terms of BNT content, reoxidation temperature, and time. Room‐temperature resistivity (ρRT) of simples sintered in N2 decreased to 102Ω·cm, and the jump in resistivity (maximum resistivity [ρmax]/minimum resistivity [ρmin]) was enhanced by three orders of magnitude through a suitable reoxidation process without sacrificing the ρRT. The Curie temperature (Tc) was shifted to a high temperature (>130°C) with an increase in the BNT content. With the addition of 4 mol% BNT, the obtained ceramic exhibited a low ρRT of 2 × 102Ω·cm, a typical PTC effect of ρmax/ρmin>103, and a Tc of 160°C.

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Ytterbium (Yb)-doped (1 -x)BaTiO 3 -xBi 4-Ti 3 O 12 (abbreviated as BT-BIT, where x = 0, 0.005, 0.01, 0.015, 0.02 and 0.03) semiconducting ceramics were fabricated by the conventional mixed oxide method, all the samples were sintered in a pure N 2 atmosphere and annealed in air for several hours. The Curie temperature (Tc) firstly increased and then decreased with the increase of BIT, which corresponded to the trend of c/a value. In addition, the effect of Yb 3? on the PTCR was also investigated. It was found that the Curie temperature was shifted to a higher level and the dielectric constant decreased with the increase of Yb 3? .

Lanthanum (La) doped BaTiO 3 -(Bi 0.5 Na 0.5 )TiO 3 (BT-BNT) positive temperature coefficient of resistivity (PTCR) ceramics were prepared by a conventional solid state reaction method. The microstructure and PTCR effect of BT-BNT ceramics were investigated by scanning electron microscopy and measurement of resistivity-temperature dependence. The BT-BNT ceramics sintered in a N 2 gas flow possessed low room-temperature resistivity (ρ RT < 10 2 ·cm) and PTCR effect wasn't remarkable (ρ max /ρ min < 10); through a proper reoxidation process, the ceramics showed a typical PTCR effect (ρ max /ρ min > 10 3 ) but with a high room-temperature resistivity (ρ RT > 10 3 ·cm). Room-temperature resistivity increased with the raising content of BNT. The Curie temperature (Tc) of BT-BNT ceramics shifted to 160 • C for the 8mol% BNT added. With the addition of 4mol% BNT, the obtained BT-BNT ceramics reoxidized at 950 • C possessed ρ RT = 10 3 ·cm and exhibited a resistivity jump (ρ max /ρ min > 10 3 ) at 150 • C. The possible mechanism underlying the PTCR behavior in BT-BNT ceramics was discussed.

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