Synthesis and physico-chemical studies of some Bisphenol Derrivatives, Polymers and Composites

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Ultrasonic Speed and Related Acoustical Parameters of 1,1ʼ-Binaphthalene-2,2ʼ-diyl Diacetate Solutions at 308.15 K

The density (ρ), viscosity (η) and ultrasonic speed (U) (2 MHz) of chloroform, THF, ethyl alcohol, ethyl acetate, 1,4-dioxane and 1,1ʼ-binaphthalene-2,2ʼ-diyl diacetate (DBNA) solutions have been determined at 308.15 K. Various acoustical parameters namely specific acoustical impedance (Z), adiabatic compressibility (κa), Van der Waals constant (b), intermolecular path length (Lf), internal pressure (π), Raoʼs molar sound function (R), relaxation time (τ), classical absorption coefficient (α/f2)cl and solvation number (Sn) have been derived from ρ, η and U data and correlated with concentration (C). A fairly good to excellent correlation has been observed between a particular parameter and C. Linear increase of Z, R, b, (α/f2)cl and τ (except EA) (R2 = 0.90 – 0.999) and linear decrease of κs, π and Lf (R2 = 0.947 – 0.995) with C supported existence of powerful molecular interactions in the solutions and further supported by nonlinear increase of Sn with C. A fairly constant Gibbs free energy of activation has been observed in all the solvent systems studied

Fabrication, mechanical and electrical study of sandwich biocomposites of epoxy resin of 1,1’-bis(3-methyl-4-hydroxyphenyl)cyclohexane

568-572A 70 % matrix of reinforcement and 20% TEA of the matrix are used in the present investigation. <span style="mso-bidi-font-weight: bold">Jute-wild almond (JWA-EMCT-20), jute-coconut (JCN-EMCT-20), jute-groundnut(JGN-EMCT-20), jute-wheat(JW-EMCT-20), jute-banana(JBN-EMCT-20) and jute-sugarcane (JSC-EMCT-20) sandwich biocomposites of epoxy resin of 1,1’-bis(3-methyl-4-hydroxy phenyl)cyclohexane have been fabricated by hand layup technique at 150oC and under 27.6 MPa pressure for 4 h using a 20% triethylamine as a curing agent. Sandwich biocomposites possess 6-26 MPa tensile strength, 2.8-53 MPa flexural strength, 0.5-1.9 kV/mm electric strength and 1.4×1010 - 2.7×1015 ohm.cm volume resistivity. JWA-EMCT-20 and JW-EMCT-20 showed better tensile strength, while<span style="mso-bidi-font-weight: bold"> JWA-EMCT-20, JCN-EMCT-20 and JBN-EMCT-20 showed better flexural strength due to their better stiffness property. Sandwich biocomposites possess fairly good electric strength (except JW-EMCT-20 and JBN-EMCT-20) and excellent volume resistivity (JW-EMCT-20 and JCN-EMCT-20) indicating their usefulness for low load bearing applications especially for housing units and as insulating materials. </span