Synthesis and biological activity of the metabolites of N-[2-(1-azabicyclo[3.3.0]octan-5-yl)ethyl]-2-nitroaniline fumarate (SK-946).

Three metabolites of N-[2-(1-azabicyclo[3.3.0]octan-5-yl)ethyl]-2-nitroaniline fumarate (SK-946), a novel central muscarinic cholinergic receptor agonist, were prepared to confirm their proposed structures, and tested for muscarinic receptor affinity in vitro.     

Surface mechanical properties of low‐molecular‐weight polystyrene below its glass‐transition temperatures

Lap shear and friction force measurements were carried out on a series of monodisperse polystyrene (PS) films below the corresponding glass‐transition temperatures. It showed that adhesion between the PS/PS interface was possible at the temperature below the bulk T_g, and the lower the molecular weight of PS, the lower the temperature at which the interfacial strength was detectable. The examination of a series of molecular weights indicated both the surface molecular motion and the magnitude of the interfacial strength were dependent on molecular weight and its distribution. And a steep increase of the friction force with increasing the test temperature was observed around 0 ∼ 30 °C. The contact angle of water versus molecular weight measurements also showed a transition at room temperature. The behavior observed in this study was supposed to be due to the increased molecular mobility, and was in good agreement with the measured surface transition temperatures by DSC. © 2000 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 38: 654–658, 2000     

Radical polyaddition of bis(α-trifluoromethyl-β-difluorovinyl) terephthalate with 1,4-dioxane

To develop a radical polyaddition reaction of 2-benzoyloxypentafluoropropene [CF₂C(CF₃)-OCOC₆H₅] (BPFP) with tetrahydrofuran (THF), the reactions of bis(α-trifluoromethyl-β-difluorovinyl) terephthalate [CF₂C(CF₃)OCOC₆H₄COOC(CF₃)CF₂] (BFP) with THF and of BPFP with 1,4-dioxane were investigated as model reactions to form 1 : 1 and 1:2 addition products of BFP with THF. This evidenced that THF is monofunctional, and dioxane is bifunctional since the 1:1 and 2:1 addition products of BPFP with dioxane were formed. The polyaddition reaction of BFP with dioxane turned out to produce a white powdery substance which was found to possess a mole ratio of BFP units to dioxane units in the polymers of 1:1. The highest molecular weight obtained was M _n = 9.9 × 10³.     

The role of a compatibilizer to saturate interfacial tension and to emulsify a polymer blend

A linear drop of the interfacial tension between polyamide 6 (PA6) and poly(propylene) (PP) upon increasing concentration of the reactive compatibilizer and a leveling-off at higher compatibilizer contents were found in this study. The reduction of the interfacial tension is compared with the reduction of the dispersed phase size of the corresponding blends. As a result, the domain size is not directly proportional to the interfacial tension under the condition that other factors are equal.