A series of chelating resins, derived from a macroreticular styrene‐divinylbenzene (2%) copolymer beads grafted with various poly(ethylene glycols) HO(CH2CH2O)nH(n = 0, 4, 9, 13) and containing thiol groups as chelating functions, have been synthesized in a three‐step reaction sequence. The structure of the functionalized resins was confirmed by IR spectrophotometry, elemental analysis, and differential scanning calorimetry. The complexation behavior of these thiol resins was investigated towards Hg(II), Cu(II), and Pb(II) ions in aqueous solution by a batch equilibration technique. The influence of pH on adsorption capacity was also examined. The adsorption values for metal ions' intake followed the order Hg(II) > Cu(II) > Pb(II). The affinity of these polymers towards Hg(II) ions was so high that the total mercury level in the liquid decreased from 20 ppm to below 10 ppb after 2 h of treatment. Polymers can be regenerated by washing with a solution of hydrochloric acid (6N) and 10% by weight of an aqueous solution of thiourea. © 1994 John Wiley & Sons, Inc.

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The rheological behavior of liquid crystal polymers is still far from completely clarified from both experimental and theoretical points of view. In this paper, the shear flow and the non-isothermal elongation flow behavior of a semirigid liquid crystal copolyester is discussed. The viscosity strongly decreases when the test temperature is increased above the crystal-nematic transition temperature: below this temperature the viscosity is very high. The thermal history strongly affects the shear viscosity. The elongational flow behavior depends also on temperature. Above the crystal-nematic transition temperature and the mesophase is easily spinnable, whereas below this temperature, the spinnability is very poor.

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