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In this study, alkaline lignin (AL), dealkaline lignin (DAL), and lignin sulfonate (SL) were liquefied in phenol with sulfuric acid (H2SO4) or hydrochloric acid (HCl) as the catalyst. The phenol-liquefied lignins were used as raw materials to prepare resol-type phenol-formaldehyde resins (PF) by reacting with formalin under alkaline conditions. The results show that phenol-liquefied lignin-based PF resins had shorter gel time at 135 degrees C and had lower exothermic peak temperature during DSC heat-scanning than that of normal PF resin. The thermo-degradation of cured phenol-liquefied lignin-based PF resins was divided into four temperature regions, similar to the normal PF resin. When phenol-liquefied lignin-based PF resins were used for manufacturing plywood, most of them had the dry, warm water soaked, and repetitive boiling water soaked bonding strength fitting in the request of CNS 1349 standard for Type 1 plywood. (c) 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 201

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The spectroscopic and electrochemical characterizations of electrochemically stable biferrocene-modified Au clusters and chemisorbed biferrocenylalkanethiols on Au(111) surface were studied. The characterizations of biferrocene-modified Au cluster using TEM, UV-vis, and NMR techniques are also reported. Two successive reversible one-electron redox waves were observed for the biferrocenylalkanethiol Au nanoclusters and biferrocenylalkanethiol monolayers on Au(111) surface in the cyclic voltammetry. Furthermore, the positive and negative current peaks for each redox wave occur at almost the same potential, and the peak current increases almost linearly with the sweep rate. Repeat scanning does not change the voltammograms, demonstrating that these monolayers are stable to electrochemical cycling. The coverages of electroactive biferrocene in the monolayers were calculated from the cyclic voltammograms. The standard electron-transfer rate constant was calculated from the splitting between the oxidation and reduction peaks.

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