Simultaneous hydrogenation and hydroacylation of vinyl groups in polybutadiene by use of a rhodium catalyst

Vinyl groups in phenyl-terminated polybutadiene (1a) containing 99% unsaturation (27% vinyl group, 73% internal olefin), and for which the average M_n is 3400, were simultaneously hydrogenated and hydroacylated with various aromatic or heteroaromatic primary alcohols in the presence of the catalytic system RhCl₃.H₂O, PPh₃ and 2-amino-4-picoline. Sterically less hindered alcohols, such as benzyl alcohol, showed greater reactivity than sterically more hindered alcohols, such as 2-naphthylmethanol and heteroaromatic primary alcohols. Vinyl groups in phenyl-terminated polybutadiene (1b) containing 99% unsaturation (45% vinyl group, 55% internal olefin) and for which the average M_n is 1300 also showed similar reactivity toward various primary alcohols under identical reaction conditions.     

Titanium oxide thin film deposited on metallic Cr substrate by RF-magnetron sputtering

In order to develop a colored mirror with hydrophilicity, TiO₂ films are deposited on the Cr and amorphous-TiO₂ substrate. In TiO₂/Cr, a mixed phase comprising of anatase and rutile is formed. In TiO₂/amorphous-TiO₂/Cr, pure anatase phase is obtained. The amorphous-TiO₂ film as interlayer tends to induce micro-columnar-shaped anatase phase. The formation of anatase phase leads to an abrupt decrease of the contact angle by UV-irradiation. Hydrophilic to hydrophobic reconversion by electron-hole recombination is retarded, which seems to be due to pure anatase phase without rutile phase.     

Synthesis and photo-catalytic degradation property of nanostructured-ZnO with different morphology

ZnO nanostructures with different morphology have been successfully fabricated by a simple relative low temperature approach at 90 °C for 5 h without surfactant assistance. These structures can be easily tailed using varied concentrations of sodium hydroxide (NaOH) and different amounts of the hydrazine hydrate (N₂H₄·H₂O). X-ray diffraction (XRD) result proves the formation of ZnO with wurtzite structure. Microstructure as revealed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM) indicates that the rod-like and chrysanthemum-like ZnO nanostructures contain many radial nanorods, which grow along the [0001] direction. Furthermore, the as-prepared ZnO nanomaterials exhibit high activity on the photo-catalytic degradation of typical persistent organic pollutants (POPs), indicating that they are promising as semiconductor photo-catalysts.     

含钼催化剂研究新进展

含钼催化剂广泛用于多种化工生产的过程,在含钼精细化学品的研究与开发中占有重要地位,简要介绍了我国近年来一些含钼催化剂的研究进展和关文献。     

乙酸与异戊醇酯化反应中沸石催化剂的改性与优选

以分子筛-HZSM-5(38),HZSM-5(55),USY和REY原粉为原料改性制备了四种催化剂.其中的HZSM-5(55)(在600℃焙烧)和REY(在300～400℃焙烧)对乙酸异戊醇酯化反应有较好的催化活性和稳定性,并讨论了催化剂失活的原因.