The interassociation equilibrium constant and interaction behavior between OH and amide group in phenolic resin/polyamide 6 blend have been investigated. There is a very strong intermolecular hydrogen bonding in the phenolic/polyamide 6 blend. KA = 639.64 is calculated from the Painter‐Coleman association model (PCAM). Quantitative description of the intermolecular hydrogen bonding number resulted from solid FTIR spectra is rather close to that predicted by PCAM. The self‐association of polyamide 6 is replaced by the interassociation in the phenolic rich region. The phenolic resin/polyamide 6 blend is miscible and phase separation does not occur throughout the blend range from room temperature to molten state, causing a high KA value. The Tg deviation of phenolic resin/polyamide 6 is negative throughout the blending range. The phenolic–polyamide 6 interaction formed is not large enough to overcome the breaking off of the self‐association of phenolic resin and polyamide 6. It is attributed to the long repeated unit of polyamide 6 which hinders the self‐association of phenolic resin, especially on phenolic rich region, consequently, increasing the entropy of polymer blend.

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The dimerization of isobutylene to diisobutylene in C4 mixture was evaluated using various catalysts such as nickel salts system, zeolite system and acidic ion exchange resin. There were shown that the strong acidic type ion exchange resin (Amberlyst 15) under 6 kg/cm2 and 60 degrees C gave rise to 90% conversion and more than 60% selectivity to diisobutylene with acceptable amounts of oligomer as a best catalyst. Therefore, Amberlyst 15 was employed to investigate the optimum reaction condition. In the batch reaction, since the catalyst activity was increased with the increasing reaction temperature, the reaction time should be shortened appropriately to prevent a high yield of oligomer. The reaction rate was increased by the increased amount of catalyst without much change in the product composition. The formation of oligomer was inhibited when a small amount of organic solvents (methyl tert-butyl ether) are attended. In the fixed-bed study, the results indicate that the increase in reaction temperature was accompanied by the increase in reaction rate, however, the selectivity to the dimer was affected. Higher WHSV will enhance the selectivity but reduce the conversion. Conclusively, the appropriate reaction condition was 45 degrees C with WHSV of 10.

Novel phosphorus-containing polymers with high-electron-affinity oxadiazole were synthesized and characterized by thermal analysis and spectroscopy (infrared, ultraviolet-visible, photoluminescence, cyclic voltammetry) measurements. These new polymers can be used as blue electroluminescent materials and as electron-transport layers in polymer light-emitting diodes. In this study, aromatic polyethers containing electrontransporting chromophores and emission chromophores were synthesized from 2,5-bis-(4-fluoroaryl)-1,3,4-oxadiazole and 2-(6-oxido-6H-dibenzϽc,eϾϽ1,2Ͼ oxaphosphorin-6-yl)-1,4-naphthalenediol (DOPO-NBQ). The effects of reaction temperature and time on the formation of polyethers were investigated to obtain optimum conditions for polyether manufacturing. All the resulting polymers were thermally stable at Ͻ460°C. The absorption peaks of these polymers were at 350-365 nm, whereas the photoluminescent peaks were at 460-481 nm. But, the intensity of polymer absorption decreased and a blue shift was observed in the photoluminescent spectra as the temperature increased. In addition, these polymers containing the electron-transporting oxadiazole indeed showed extra reduction potentials in cyclic voltammetry measurements.

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