Two series of waterborne polyurethane-urea anionomers were prepared by a polyaddition reaction with isophorone diisocyanate, poly(tetramethylene oxide) glycol (weight-average molecular weight ϭ 1000), dimethylol propionic acid (DMPA), and ethylene diamine as chain extenders. Triethylamine (TEA) or 28:1 mol/mol ammonium hydroxide (NH 4 OH)/cupric hydroxide [Cu(OH) 2 ] was used as a neutralization agent [NH(C 2 H 5 ) 3 ϩ or NH 4 ϩ / Cu 2ϩ counterion] for the pendant COOH group of DMPA. The effects of the degree of neutralization and counterion on the particle size of the dispersions, the conductivity, and the antibacterial and mechanical properties of polyurethaneurea anionomer films were investigated. The particle sizes of the two sample series dispersions decreased with an increasing degree of neutralization. Aqueous dispersions of polyurethane-urea anionomers with particle sizes of 30 -120 nm were stable for about 3 months. By infrared spectroscopy, it was found that TEA-based samples (T series) had higher fractions of hydrogen-bonded carbonyl groups in the ordered region than NH 4 OH/Cu(OH) 2 -based samples (S series). However, the fractions of hydrogen-bonded carbonyl groups in the disordered region of the S-series samples were higher than those of the T-series samples. The conductivities of the S-series film samples were higher than those of the T-series samples. However, the T-series film samples commonly had higher tensile strengths and initial moduli than the S-series samples.

No abstract

The reaction of benzil 1‐ureidoethylidenehydrazones 8 with a mixture of triphenylphosphine, carbon tetrachloride, and triethylamine provides a general route to 7H‐imidazo[1,2‐b][1,2,4]triazoles 18 via the thermal reaction of the expected ketoazine carbodiimide intermediates 13, and the structure of 18 was confirmed by X‐ray crystallographic analysis.

No abstract

Oxirane derivatives R 0030 Efficient Synthesis of 2(S)-[1(S)-Azido-2-phenylethyl]oxirane. -The approach to title compound (VI), an educt for the preparation of the antiviral substance amprenavir, is suitable for large-scale preparation. -(PARK, S.; LEE, S.; KANG*, H.-J.; Bull.