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Two kinds of nylon 4 having an acyllactam group at one or both chain ends were synthesized by the anionic ring‐opening polymerization of 2‐pyrrolidone using N‐benzoyl‐2‐pyrrolidone (BP) or N,N′‐isophthaloylbis‐2‐pyrrolidone (IPP) and potassium tert‐butoxide as an initiator and a catalyst, respectively, and carefully isolated with the suppression of moisture adsorption. The acyllactam at one chain end in the low molecular weight of nylon 4 was quantitatively converted to other functional groups such as carboxy, amine and so on, which were confirmed by matrix‐assisted laser desorption/ionization time‐of‐flight (MALDI TOF) mass spectroscopy. Terminal acyllactam groups telechelating in the nylon 4 at both chain ends were also modified to carboxy and amino groups. From the thermogravimetric analysis (TGA), thermal decomposition point of the modified nylon 4 was increased in comparison with that of the original acyllactam‐type nylon 4, although the acyllactam chain end caused the backbiting depolymerization accompanied with the generation of 2‐pyrrolidone monomer. The direct heating of the acyllactam‐telechelic low molecular weight of nylon 4 mixed with the diamine in bulk also led to improve its thermal stability significantly by the chain extension through the polyaddition reaction. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011

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Four kinds of bio-based polyurethanes bearing hydroxy groups in the pendants were synthesized by the polyaddition of D-mannitol-and D,L-erythritol-derived diols (1,2:5,6di-O-isopropylidene-D-mannitol and 1,2-O-isopropylidene-D,Lerythritol) with hexamethylene diisocyanate and methyl (S)-2,6diisocyanatohexanoate and the subsequent deprotection of the isopropylidene groups. They were hydrolyzed much more quickly than the corresponding protected polyurethanes at 50 C and pH 7.0, although their hydrolytic degradation rate was lower than that of polyurethanes with saccharic and glucuronic lactone groups, which had been reported in our previous articles. The introduction of D-mannitol units to the polyetherpolyurethanes containing poly(oxytetramethylene) glycol units also enhanced their hydrolyzibility. V C 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 49: [976][977][978][979][980][981][982][983][984][985] 2011

A thiophene derivative containing a thiol group, (3-thienylethyl)-11-mercaptoundecanoate, was deposited on a gold surface. The thiophene monomer formed a self-assembled monolayer (SAM). The structure of the SAM was characterized by X-ray photoelectron spectroscopy (XPS). The molecules were adsorbed at the thiol group with end-on configuration. Using the ratio of signal intensity of the two types of sulfur atoms in the thiol and thiophene groups, the escape depth of a photoelectron of the SAM was estimated to be 30 Å, which is slightly longer than the empirical value of 33 Å for SAMs of alkanethiols. This is because the bulky thiophene ring and the flexible ester group prevent the monolayer from forming a densely packed structure like the alkanethiol SAMs.