SbstractA series of vinyl ester and polyurethane interpenetrating polymer networks were prepared by changing the component ratios of VER (Vinyl ester) and PU (Polyurethane) and the polymerization process was confirmed with Fourier Transform infrared spectroscopy. IPN (Inter Penetrating Polymer Network -VER/PU) reinforced Glass and carbon fiber composite laminates were made using the Hand lay up technique. The Mechanical properties of the E-glass and carbon fiber specimens were compared from tests including Tensile, Compressive, Flexural, ILSS (Inter Laminar Shear Strength), Impact & Head Deflection Test (HDT). The IPN Reinforced Carbon fiber specimen showed better results in all the tests than E-Glass fibre reinforced IPN laminate with same thickness of the specimen, according to ASTM standards. It was found that the combination of 60%VER and 40%PU IPN exhibits better impact strength and maximum elongation at break, but at the slight expense of mechanical properties such as tensile, compressive, flexural, ILSS properties. The morphology of the unreinforced and reinforced composites was analyzed with help of scanning electron microscopy.

We report an effective way to develop thermally strong and multifunctional cardanol‐based nanocomposite using graphene as nanofiller. New benzoxazine monomer was synthesized by using bio‐product cardanol, aniline, and formaldehyde. Benzoxazine‐graphene nanocomposites (pba‐g) were prepared by in situ polymerization. The pba‐g precursor was copolymerized with diglycidyl ether of bisphenol‐A at different loading level to make copolymer. Benzoxazine monomer was characterized by Fourier transform infra red spectroscopy (FTIR) and NMR. Graphene was characterized by FTIR, XRD, SEM, and TEM. Benzoxazine‐graphene/epoxy (epba‐g) nanocomposites have been characterized by FTIR, thermogravimetric analysis, and inductance capacitance and resistance meter. Both the thermal and electrical properties of epba‐g were significantly improved compared with those of pure epoxy (ep) matrix. The dielectric constant of epba‐g was 11, which was four times higher than that of pure epoxy matrix. POLYM. COMPOS., 36:1–7, 2015. © 2014 Society of Plastics Engineers

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A series of E-Glass fiber reinforced polyurethane (PU)/vinyl ester(VER) resin interpenetrating polymer network (IPN) composites were prepared. The Mechanical Properties like tensile, flexural and impact of IPN composite were studied. Results revealed that addition of PU increases the impact strength by 8.33%, 7.69%, 14.28%, 12.5%, 11.11% for the proportinate of 0%PU, 10%PU, 20%PU, 30%PU, 40%PU, 50%PU respectively, at the slight expense of decrease in flexural and tensile modulus. The obtained experimental results were compared with the Finite Element Analysis data's (ANSYS 10). The comparison shows good agreement with experimental data's.

Anthraquinone dicyanate was prepared by treating CNBr with 1,4 dihydroxy anthraquinone in the presence of triethylamine at -5 to 5°C. The dicyanate was characterized by Fourier transform infrared (FT-IR) spectroscopy. The prepared dicyanate was blended with commercial epoxy resin in different ratios and cured at 120 °C for 1 h, 180 °C for 1 h and post-cured at 220 °C for 1h using diamino diphenyl methane as the curing agent. Castings of neat resin and blends were prepared and characterized by FTIR analysis. The composite laminates were also fabricated from the same composition. The mechanical properties such as tensile strength, flexural strength and fracture toughness were measured as per ASTM D 3039, D 790 and D 5528, respectively. The tensile strength increased with increasing cyanate content (3, 6, and 9%) from 52.1 to 80.1 MPa. The values of fracture toughness also increased from 0.7671 kJ m-2 for the neat epoxy resin to 0.9168 kJ m-2 for the 9% cyanate ester epoxy-modified system. The thermal properties were also studied. The 10% weight loss temperature of pure epoxy was 358 °C and it increased to 381 °C with incorporation of cyanate ester resin. The incorporation of cyanate ester up to a 9% loading level did not affect the glass transition temperature to a very great extent.

The performance of epoxy/cenosphere syntactic foams cured using phenalkamine (PA) were analyzed and characterized. The PA system was found to cure faster at room temperature, had lower density, and lower water absorption values. The thermogravimetric analysis result implied higher thermal stability. The cure studies using DSC inferred faster cure reaction in the ambient temperature conditions. The compression studies confirmed that unlike the epoxy system based on conventional triethylenetetramine curative, PA‐based system did not undergo brittle failure. This was also confirmed with the scanning electron microscope images. Dynamic mechanical analysis inferred the glass transition temperatures (Tg) as 81.4°C. The specific modulus and specific strength were higher for 40% cenosphere loading in PA‐based syntactic foams. As the need for light weight core materials is continually increasing, there is a great possibility for the utilization of this novel bio‐based curing agent to produce sustainable products. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 44189.

Bis(4-cyanato 3,5-dimethylphenyl) naphthylmethane was prepared by treating CNBr with bis(4-hydroxy 3,5dimethylphenyl) naphthylmethane in the presence of triethylamine at À5 to 58C. The dicyanate was characterized by FT-IR and NMR techniques. The prepared dicyanate was blended with commercial epoxy resin in different ratios and cured at 1208C for 1 hr, 1808C for 1 hr, and post cured at 2208C for 1 hr using diamino diphenyl methane (DDM) as curing agent. Castings of neat resin and blends were prepared and characterized by FT-IR technique. The morphology of the blends was evaluated by SEM analysis. The composite laminates were also fabricated from the same composition using glass fiber. The mechanical properties like tensile strength, flexural strength, and fracture toughness were measured as per ASTMD 3039, D 790, and D 5528, respectively. The tensile strength increased with increase in cyanate content (3, 6, and 9%) from 322 to 355 MPa. The fracture toughness values also increased from 0.7671 kJ/m 2 for neat epoxy resin to 0.8615 kJ/m 2 for 9% cyanate ester epoxy modified system. The thermal properties were also studied. The 10% weight loss temperature of pure epoxy is 3588C and it increased to 3988C with incorporation of cyanate ester resin. The incorporation of cyanate ester up to 9% loading level does not affect the T g to a very great extent. POLYM. COMPOS., 29:709-716, Synthesis of Monomer PrecursorSynthesis of Bis(4-hydroxy 3,5-dimethylphenyl) Naphthyl Methane. Into a three-necked flask equipped with a condenser, a Dean-stark water separator and a nitrogen Correspondence to: M. Sarojadevi;

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