The analysis of scientific-technical literature has shown the prospectiveness of applyinghigh-temperature thermoplastic polymers - among which there are complex aromatic polyesters -as constructive materials. Mixed po...The analysis of scientific-technical literature has shown the prospectiveness of applyinghigh-temperature thermoplastic polymers - among which there are complex aromatic polyesters -as constructive materials. Mixed polyarylates of DV mark based on diphenilolpropane and themixture of iso- and terephtale acid are mentioned to make the most valuable practical interest. Forimproving technological and exploitation properties the authors of the article have suggested toreinforce the polymer linking element with uglen-9 mark. Combination of the composition compo-nents was realized within the rotating electromagnetic field with the help of non-equiaxial ferro-magnetic elements. The study of tribotechnical characteristics (coefficient of friction, intensity oflinear wear, temperature in the contact zone "polymer specimen - counterbody" of elaborated car-bon plastics) has been made at the disc machine of friction. Investigation of exploitation regimes’(specific pressure and slip velocity) influence on the mentioned properties of the initial polymer hasshown that polyarylate can be recommended for work at values of PV criterion not greater than 1.2MPa · m/s. Hardening the exploitation regimes is accompanied by the catastrophic wear of plastic.Reinforcement of polyarylate with carbon fibre is noted to enable significant improvement (to de-crease the coefficient of friction, to increase resistance to wear) of tribotechnical characteristics ofcarbon plastics. The most optimal is the content of carbon fibre in polyarylate in amount of 25mass.%.展开更多
Solid state ^(13)C NMR spectra of a series of naphthol-1 and naphthol-2-arylazo--deriva- tives were studied and compared with respective results in solutions.Signals of carbon nuclei of naphthalene ring were assigned....Solid state ^(13)C NMR spectra of a series of naphthol-1 and naphthol-2-arylazo--deriva- tives were studied and compared with respective results in solutions.Signals of carbon nuclei of naphthalene ring were assigned.Tautomeric forms of compounds were determined.It was shown that 4-(p-NO_2C_6H_4)-azonaphthol-1 and 1-(p-NO_2C_6H_4)-azonaphthol-2 in solid state existed ex- clusively in quinohydrazone form.The other two compounds——1-(C_6F_5)-azonaphthol-2 and 2-(p- CH_3C_6H_4)-azonaphthol-1 in solid state were not found in the form of individual tautomeric mixtures but in respective tautomeric equilibrium form.Thus,during transition from liquid to solid state, the tautomeric equilibrium was practically unchanged.In solid state it was found that rotation around aryl-N bond was hindered in the time scale of NMR spectroscopy.展开更多
文摘The analysis of scientific-technical literature has shown the prospectiveness of applyinghigh-temperature thermoplastic polymers - among which there are complex aromatic polyesters -as constructive materials. Mixed polyarylates of DV mark based on diphenilolpropane and themixture of iso- and terephtale acid are mentioned to make the most valuable practical interest. Forimproving technological and exploitation properties the authors of the article have suggested toreinforce the polymer linking element with uglen-9 mark. Combination of the composition compo-nents was realized within the rotating electromagnetic field with the help of non-equiaxial ferro-magnetic elements. The study of tribotechnical characteristics (coefficient of friction, intensity oflinear wear, temperature in the contact zone "polymer specimen - counterbody" of elaborated car-bon plastics) has been made at the disc machine of friction. Investigation of exploitation regimes’(specific pressure and slip velocity) influence on the mentioned properties of the initial polymer hasshown that polyarylate can be recommended for work at values of PV criterion not greater than 1.2MPa · m/s. Hardening the exploitation regimes is accompanied by the catastrophic wear of plastic.Reinforcement of polyarylate with carbon fibre is noted to enable significant improvement (to de-crease the coefficient of friction, to increase resistance to wear) of tribotechnical characteristics ofcarbon plastics. The most optimal is the content of carbon fibre in polyarylate in amount of 25mass.%.
基金The project was supported by the National Natural Science Foundation of China.
文摘Solid state ^(13)C NMR spectra of a series of naphthol-1 and naphthol-2-arylazo--deriva- tives were studied and compared with respective results in solutions.Signals of carbon nuclei of naphthalene ring were assigned.Tautomeric forms of compounds were determined.It was shown that 4-(p-NO_2C_6H_4)-azonaphthol-1 and 1-(p-NO_2C_6H_4)-azonaphthol-2 in solid state existed ex- clusively in quinohydrazone form.The other two compounds——1-(C_6F_5)-azonaphthol-2 and 2-(p- CH_3C_6H_4)-azonaphthol-1 in solid state were not found in the form of individual tautomeric mixtures but in respective tautomeric equilibrium form.Thus,during transition from liquid to solid state, the tautomeric equilibrium was practically unchanged.In solid state it was found that rotation around aryl-N bond was hindered in the time scale of NMR spectroscopy.
