Hydrophilic aromatic polyurethane (HAPU) microspheres were prepared through dispersion polymerization of a rosin-based polyurethane dispersion with C=C and styrene (St). The effects of the monomer ratio (i.e., waterborne rosin-based aromatic polyurethane (WRPU) to St), dispersant level, and reaction temperature on the properties of the microspheres were investigated; the effects of pH and adsorption temperature on the adsorption capacity of Orange II were also studied. The microspheres were characterized using Fourier transform infrared spectroscopy, energy-dispersive spectrometry, thermogravimetric analysis, laser particle size analysis, and scanning electron microscopy. The results showed that HAPU microspheres have been successfully synthesized and the produced microspheres exhibited good thermal stability and monodispersion. The optimum reaction conditions for the preparation of the microspheres were determined as a monomer ratio ( m WRPU / m St ) of 6:4 with 8 wt % poly(vinyl pyrrolidine) (on the basis of the mixed monomer) at 80 °C for 8 h. Under these conditions, the average particle size of the synthetic microspheres was 120 nm and the particle size distribution index was 0.442. The microspheres’ adsorption capacity for Orange II reached 17.53 mg·g –1 when the solid–liquid ratio was 1 g·L –1 , with an initial concentration of 100 mg·L –1 at pH 5, and the adsorption was conducted at 313 K for 3 h.

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Carboxyl-functionalized polymer microspheres with a rosin moiety were prepared through dispersion polymerization using styrene, disproportionated rosin ester, and methylacrylic acid as raw materials. The effects of dispersion medium (ethanol/water) ratio, monomer mass proportion and initiator concentration on the polymer microspheres were studied. Scanning electron microscopy, laser particle size analysis, thermogravimetric analysis and Fourier transform infrared spectroscopy were used to characterize the microspheres, and their carboxyl contents were determined by the conductance titration method. The adsorption of methylene blue of the microspheres was also investigated. The results showed that rosin-based carboxyl-functionalized polymer microspheres were successfully synthesized. The microspheres exhibited smooth, spherical shapes with good monodispersity and high thermal stability. The carboxyl content of the microspheres prepared under optimum conditions was 0.089 mmolÁg À1 , with the average particle size approximately 950 nm. With increasing carboxyl contents of the polymer microspheres, their methylene blue adsorption capacities increased. The maximum methylene blue adsorption capacity of the microspheres was 59.55 mgÁg À1 in the highest carboxyl content.

Ultrathin amorphous Ni–Ti film is investigated as conductive diffusion barrier layer to integrate La0.5Sr0.5CoO3∕PbZr0.4Ti0.6O3∕La0.5Sr0.5CoO3 (LSCO/PZT/LSCO) capacitors on silicon. X-ray photoelectron spectroscopy results demonstrate that Ni in LSCO∕Ni–Ti∕Si heterostructure is not oxidized after 550°C annealing in oxygen. The structural properties of LSCO∕PZT∕LSCO∕Ni–Ti∕Si are characterized by x-ray diffraction and transmission electron microscopy. It is found that Ni–Ti film is still amorphous and that there are no discernible reactions at the interfaces of the sample. LSCO/PZT/LSCO capacitor, measured at 5V, possesses very good ferroelectric properties, such as low coercive field (∼1.28V), high remnant polarization (∼27.9μC∕cm2), and good fatigue-free characteristic, implying that ultrathin amorphous Ni–Ti film can be used as barrier layer for fabricating high-density ferroelectric random access memories.

Analysis of size effects in Pb ( Zr 0.54 Ti 0.46 ) O 3 thin film capacitors with platinum and LaNiO 3 conducting oxide electrodes Diffusion of oxygen tracer into deuterium-gas-baked Ir O x ∕ Pb ( Zr , Ti O 3 ) Pt capacitors and Pb ( Zr , Ti ) O 3 Pt films J. Appl. Phys. 98, 094107 (2005); 10.1063/1.2099508 Direct observation of region by region suppression of the switchable polarization (fatigue) in Pb(Zr,Ti)O 3 thin film capacitors with Pt electrodes Both FePt/ PbZr 0.4 Ti 0.6 O 3 ͑PZT͒ / Pt and Pt/PZT/Pt ferroelectric capacitors have been fabricated onSi substrates. It is found that up to 10 9 switching cycles, the FePt/PZT/Pt capacitor, measured at 50 kHz, with polarization decreased by 57%, is superior to the Pt/PZT/Pt capacitor by 82%, indicating that an intermetallic FePt top electrode can also improve the fatigue-resistance of a PZT capacitor. Maximum dielectric constants are 980 and 770 for PZT capacitors with FePt and Pt, respectively. This is attributed to the interface effect between PZT film and the top electrode since the interfacial capacitance of FePt/PZT is 3.5 times as large as that of Pt/PZT interface.