A series of putative mono- and binuclear copper(II) complexes, of general formulas [CuL](ClO(4)) and [Cu(2)L](ClO(4))(2), respectively, have been synthesized from lateral macrocyclic ligands that have different compartments, originated from their corresponding precursor compounds (PC-1, 3,4:9,10-dibenzo-1,12-[N,N'-bis[(3-formyl-2-hydroxy-5-methyl)benzyl]diaza]-5,8-dioxacyclotetradecane; and PC-2, 3,4:9,10-dibenzo-1,12-[N,N'-bis[(3-formyl-2-hydroxy-5-methyl)benzyl]diaza]-5,8-dioxacyclopentadecane). The precursor compound PC-1 crystallized in the triclinic system with space group P(-)1. The mononuclear copper(II) complex [CuL(1a)](ClO(4)) is crystallized in the monoclinic system with space group P2(1)/c. The binuclear copper(II) complex [Cu(2)L(2c)](ClO(4))(2) is crystallized in the triclinic system with space group P(-)1; the two Cu ions have two different geometries. Electrochemical studies evidenced that one quasi-reversible reduction wave (E(pc) = -0.78 to -0.87 V) for mononuclear complexes and two quasi-reversible one-electron-transfer reduction waves (E(1)(pc) = -0.83 to -0.92 V, E(2)(pc) = -1.07 to -1.38 V) for binuclear complexes are obtained in the cathodic region. Room-temperature magnetic-moment studies convey the presence of antiferromagnetic coupling in binuclear complexes [mu(eff) = (1.45-1.55)mu(B)], which is also suggested from the broad ESR spectra with g = 2.10-2.11, whereas mononuclear complexes show hyperfine splitting in ESR spectra and they have magnetic-moment values that are similar to the spin-only value [mu(eff) = (1.69-1.72)mu(B)]. Variable-temperature magnetic susceptibility study of the complex shows that the observed -2J value for the binuclear complex [Cu(2)L(1b)](ClO(4))(2) is 214 cm(-1). The observed initial rate-constant values of catechol oxidation, using complexes as catalysts, range from 4.89 x 10(-3) to 5.32 x 10(-2) min(-1) and the values are found to be higher for binuclear complexes than for the corresponding mononuclear complexes.

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A series of binuclear macrocyclic copper(i1) complexes [Cu,L] [CIO,], have been prepared in which the two copper(ii) ions are placed in two geometrically distinct co-ordination environments, comprising saturated and unsaturated nitrogen-donor sets. Cyclic voltammetry has revealed two reduction couples, Cu"Cu" Cu"Cu' and Cu"Cui --+ Cu'Cu'. The first is sensitive to the macrocyclic structure as well as to electronic effects of the substituents at the aromatic ring of the ligand system, shifting to positive potentials as the macrocycle size increases. The comproportionation constants Kcom for the mixedvalence CulCuii complexes have been determined electrochemically. Cryomagnetic investigations (80-300 K) reveal a weak antiferromagnetic spin exchange between the copper(l1) ions within each complex (J = -85 to -1 95 cm-l).

Four different samples of ferrocene-grafted hydroxyl-terminated polybutadiene (Fc-HTPB), containing 0.20, 0.52, 0.90, and 1.50 wt % iron, were synthesized by the Friedel-Crafts alkylation of ferrocene with hydroxyl-terminated polybutadiene (HTPB) in the presence of AlCl 3 as a (Lewis acid) catalyst. The effects of the reaction conditions on the extent of ferrocene substitution were investigated. The Fc-HTPBs were characterized by IR, ultraviolet-visible, 1 H-NMR, and 13 C-NMR spectra. The iron content and number of hydroxyl groups were estimated, and the properties, including thermal degradation, viscosity, and propellant burning rates (BRs), were also studied. The thermogravimetric data indicated two major weight loss stages around 395 and 500 C. These two weight losses were due to the depolymerization and decomposition of the cyclized product, respectively, with increasing temperature. The Fc-HTPB was cured with toluene diisocyanate and isophorone diisocyanate separately with butanediol-trimethylolpropane crosslinker to study their mechanical properties. Better mechanical properties were obtained for the gumstock of Fc-HTPB polyurethanes with higher NCO/OH ratios. The BRs of the ammonium perchlorate (AP)-based propellant compositions having these Fc-HTPBs (without dilution) as a binder were much higher (8.66 mm/s) than those achieved with the HTPB/ AP propellant (5.4 mm/s).

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