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This paper evaluated the effect of multiwall carbon nanotube (MWCNT) on the properties of PBT/PC blends. The nanocomposites were obtained by melt blending MWCNT in the weight percentages 0.15, 0.3, and 0.45 wt% with PBT/PC blends in a high performance corotating twin screw extruder. Samples were characterized by tensile testing, dynamic mechanical analysis, thermal analysis, scanning electron microscopy, and X-ray diffraction. Concentrations of PBT and PC are optimized as 80 : 20 based on mechanical properties. A small amount of MWCNT shows better increase in the thermal and mechanical properties of the blends of PBT/PC nanocomposite when compared to nanoclays or inorganic fillers. The ultimate tensile strength of the nanocomposites increased from 54 MPa to 85 MPa with addition of MWCNT up to 0.3% and then decreased.The tensile modulus values were increased to about 60% and the flexural modulus was more than about 80%. The impact strength was also improved with 20% PC to about 60% and with 0.15% MWCNT to about 50%. The HDT also improved from 127 ∘ C to 205 ∘ C. It can be seen from XRD result that the crystallinity of PBT is less affected by incorporating MWCNT. The crystallizing temperature was increased and the MWCNT may act as a strong nucleating agent.

4-(Dihydroxyboryl)-3-nitrobenzoic acid, C7H6BNO6, M(r) = 210.94, monoclinic, P2(1)/n, a = 10.542 (2), b = 6.411 (1), c = 13.105 (4) A, beta = 106.47 (2) degrees, V = 849.3 (4) A3, Z = 4, Dm = 1.65 (flotation in CCl4/1,2-dibromoethane), Dx = 1.649 Mg m-3, lambda(Mo K alpha) = 0.71073 A, mu = 0.135 mm-1, F(000) = 432, T = 293 K, R = 0.0530 for 1328 observed reflections with F > 2 sigma(F). The molecule is flat [the carboxy and nitro groups are rotated 5.8 (4) and 1.9 (4) degrees, respectively, out of the plane] with the boronic acid group almost normal to the plane of the benzene ring, 92.4 (3) degrees. The B atom and one O atom of the nitro group are separated by only 2.457 (4) A implying an interaction that is consistent with observed chemical behavior.

N,N-Dimethyl formamide (DMF) and N,N-diphenyl formamide (DPF) complexes of six lanthanide perchlorates of the composition M(DMF)8(C104)3 and M(DPF), (ClO,), where M = La, Ce, Pr, Nd, Sm, or Y have been prepared and characterized. The infrared spectra show that the amide is bonded to the metal through oxygen. Conductivity, molecular weight, and spectral studies indicate coordinationnumbers of eight and six for DMF and DPF complexes respectively, with the perchlorate groups remaining ionic.

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SYNOPSISFree radical copolymerization of glycidyl methacrylate ( GMA) and N-vinyl-2-pyrrolidone (VPD) was carried out using 2,2'-azobisisobutyronitrile ( AIBN) , in chloroform at 60°C.The polymers were characterized by IR and 13C-NMR spectroscopic methods. The percentage composition of the copolymers were established by microelemental analysis and by 13C-NMR spectroscopy. The copolymerization reactivity ratios were computed using the Fineman-Ross method, the Kelen-Tudos method, and the extended Kelen-Tudos method. The molecular weights of the copolymers were obtained by GPC measurements. Thermal properties of the homo-and copolymers were also studied by thermogravimetric analysis. The copolymers were tested as adhesives for leather-to-leather and leather-torubber bonding.