The research on phenolic resin modified by nanoparticles and used for magnesite-carbon brick binder
The research method use nanoparticles to modify the phenolic resin binder for magnesite-carbon brick. The normal detection indexes of phenolic resins is suited to used as the binder. FESEM images show that the nanoparticles are distributed uniformly without agglomeration almost. The physical-chemical property analyses show that the magnesite-carbon brick using this modified phenolic resin as binder possesses a low apparent porosity and a high bulk density and compression strength. Especially, the compression strength of the magnesite-carbon bricks after heat treatment for 200°C×12h increase to 43.94MPa and 41.35MPa, respectively. The results also show that with the increase of heat treatment temperature, the compression strength and the bulk density of magnesite-carbon bricks decrease and the apparent porosity magnesite-carbon bricks increases. The physical-chemical property shows a significant change from 200°C to 1100°C. However the change is not obviously from 1100°C to 1550°C and shows worse trend with the increase of heat treatment temperature.
Addition curable phenolic resins based on ethynyl phenyl azo functional novolac
Abstract Novel addition curable phenolic resins bearing terminal ethynyl groups anchored to benzene ring through a phenyl azo linkage were realized by the coupling reaction between novolac and 3-ethynyl phenyl diazonium salt. The diazo-coupling occurred to a maximum of 50 mol%. The apparent molecular weight, determined from gel permeation chromatography showed a downward drift with increase in degree of acetylene substitution. The resin underwent curing in a broad temperature range 140–240 °C. Analyses using a model compound indicate that the curing occurs via various addition polymerization of acetylene groups. The thermal stability and anaerobic char yield of the polymers increased proportional to the crosslinking and were considerably superior to those of a conventional resole. Isothermal pyrolysis studies implied the possibility for the decomposition occurring mainly by loss of nitrogen gas, and hydrocarbon to form mostly an amorphous char.
Lupin alkaloids from teratogenic and nonteratogenic lupins. II. Identification of the major alkaloids by tandem gas chromatography-mass spectrometry in plants producing crooked calf disease.
The major alkaloids of lupin plants producing crooked calf disease were identified by tandem gas chromatography-mass spectrometry and infrared analysis. The gas chromatography peak invariably present in teratogenic plants proved to be anagyrine. A minor but irregular contaminant of the peak was α-isolupanine. Other alkaloids present but apparently not associated with crooked calf disease were lupanine and two others that were probably epimethoxylupanine and 5,6-dehydrolupanine.