Synthesis and characterization of polymer nanocomposites consisting of diglycidyl ether of bisphenol-A with inorganic as well as organically modified nanosized clay fillers, for example, vermiculites and montmorillonite, obtained from trade, are studied. Confirmations of intercalation and exfoliation characteristics of these fillers into the cured epoxy resin matrix have been investigated by wide angle X-ray diffraction studies. Scanning electron microscopy and atomic force microscopy techniques have been adopted to assess the nature of filler dispersion, size of the agglomerates, and the polymer-filler adhesion. While significant improvement in the mechanical properties (i.e., tensile, flexural strength, and modulus) has been observed, the thermo-oxidative stability of the composites measured by thermogravimetric analysis showed only marginal improvement. V C 2011 Wiley Periodicals, Inc. J Appl Polym Sci 124: [3236][3237][3238][3239][3240][3241][3242][3243][3244] 2012

1007anisotropic thermal parameters for all except 23 non-hydrogen atoms, due to the limitations of SHELXTL. The 23 atoms left as isotropic were normal carbon atoms. Hydrogen atoms were included at calculated positions by using a riding model, with C-H of 0.96 A and UH = 1.2U*c. The largest shift in the final cycle of refinement was 0.005 for y of C(57). There are no exceptionally short intermolecular contacts in the structure.The final difference map has 50 peaks with heights between 1.0 and 2.7 e A-3. Four of the largest fifteen appear to be hydride ligands. These were not well-behaved upon refinement, but contour maps drawn through and parallel to the Ir2CuC12(C0)2 (20) The absorption correction is made by using Program XABS, B.Moezzi, Ph.D. Dissertation, University of California, Davis. The program obtains an absorption tensor from F, -F, difference.plane reveal that these electron densities have radial symmetry and central maxima. Their presence can also be inferred from the vacant coordination sites at Ir. Acknowledgment. We thank t h e United States National Science Foundation (CHE-8519557) and NATO (86/0793) for support, Johnson Matthey Inc. for a loan of iridium salts, M. Cowie for useful discussion and permission to quote his results, a n d K. Caulton for comments. Supplementary Material Available:Complete tables of bond distances and angles, hydrogen atom positions, and anisotropic thermal parameters (7 pages); a listing of structure factor amplitudes (70 pages). Ordering information is given on any current masthead page. Addition of the Pt-H bond of [~~~~S-P~(H)(PE~~)~(THF)]+ to the CEC triple bond of the alkynylsubstituent of O=PPhz(CzCPh) occurs regioselectively to give a Pt,P p-alkenylidene complex. Similar addition of a Pt-H bond to the trialkynylphosphine oxide O = P ( C E C C M~~)~ presumably occurs also, but a facile insertion rearrangement takes place to form a novel 2-alkylidene-l,2-dihydro-3-phosphete P-oxide ligand. Complexes containing this heterocyclic alkenyl ligand react with molecular hydrogen a t -78 OC and at atmospheric pressure to give neutral monohydride complexes. The X-ray structure of one such complex has been determined (trans-Pt C=C(CMe3)P(OBF3) ( C 4 C M e 3 ) C = C ( CMe3) (H)] [P( PI-)^] 2( H)]; monoclinic; B1/c; 2 = 4; u = 11.006 (4) d , b = 21.435 (5) A, c = 19.518 (5) A; ( ? = 100.72 (3)'. Other reaction chemistry and a discussion of proposed mechanisms for the formation of these unusual complexes are reported.

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Carbon fibre-reinforced composites of conventional diglycidyl ether of bisphenol-A (DGEBA) and liquid diglycidyl ether of bisphenol-C (DGEBC) were prepared, using 4,4'-diaminodiphenylmethane (DDM) or 4,4'-diaminodiphenylsulfone (DDS) curing agent and evaluated for their physical properties (density, void content) and mechanical properties (flexural strength and interlaminar shear strength). Thick films of the neat resin were also prepared and their flexural strength has been studied. It is observed that DGEBC-curing agent system shows improved properties compared to DGEBA-curing agent system. ZUSAMMENFASSUNG:Kohlefaserverstarkte Composites von konventionellem Bisphenol A-Diglycidylether (DGEBA) oder flussigem Bisphenol C-Diglycidylehter (GGEBC) mit 4,4'-Diaminodiphenylmethan (DDM) oder 4,4'-Diaminodiphenylsulfon (DDS) als Harter wurden hergestellt. Physikalische (Dichte, Leervolumina) und mechanischen Eigenschaften (Biegefestigkeit, Scherfestigkeit) wurden ermittelt. Dicke Filme der reinen Harze wurden ebenfalls hergestellt und deren Biegefestigkeit gemessen. Die Eigenschaften der DGEBC-Laminate ubertreffen die der DGEBA-Laminate.