Graphene has drawn a great attention in the recent research innovations mainly due to its structural geometry, which is composed of one-atom thick planar sheet of hexagonally arrayed sp2 carbon atoms. Development of nanocomposites utilising graphene as the nanofiller offer desired properties to the added polymer matrix. Furthermore, incorporation of functional groups such as hydroxyl, epoxy, carboxyl, etc. on the basal plane of graphene enhances the interaction with the polymer matrices. Better interaction between the nanofiller and the polymer leads to exfoliation of the nanofiller in the matrices, which indeed significantly improves the physical, mechanical, thermal, electrical, electronic properties, etc., of the polymer. The review article explores the recent research findings on the development of polymeric nanocomposites utilising pure and functionalised graphene. The article focuses on the method of synthesis of graphene and functionalised graphene, followed by their characterisation methods and inferences. It also summarises the routes for the preparation of graphene and modified graphene-based polymer nanocomposites. The work highlights the enhancement of properties observed due to the addition of graphene and modified graphene to the polymer matrices. Several surface modifications done on GNS in order to achieve better dispersion of the same in the polymer matrix has been discussed. The review article portrays the recent research reports on graphene and modified graphene-based polymer nanocomposites. Techniques such as cryomilling, latex technology and lyophilisation as applied to polymer nanocomposites have been reviewed. Also, each of the literatures has been reviewed under the synthesis of filler and the preparation of the polymer nanocomposite separately which would serve as a guidance for future research. Literatures in which different carbon nanofillers have been compared to find the optimum filler has also been discussed.

Magnetically active elastomer materials were prepared by incorporating nickel powder in synthetic elastomeric matrices, polychloroprene and nitrile rubber. Cure characteristics, mechanical, electrical and magnetic properties were experimentally determined for different volume fractions of magnetoactive filler. The cure time decreases sharply for initial filler loading and the decrease is marginal for additional loading of filler. The tensile strength and modulus at 100% strain was found to increase with increase in the volume fraction of nickel due to reinforcement action. The magnetic impedance and a.c. conductivity are found to increase with increase in volume fraction of nickel as well as frequency.

This work deals with the study of effect of multiwalled carbon nanotubes (MWNT) on the tensile hysteresis behavior of carboxylated nitrile rubber composites under various cyclic strain levels (5, 25, and 300%). The presence of thermo‐labile ionic crosslinks as well as interfacial stick‐slip motion of filler in the matrix was found to enhance both Mullins effect and hysteretic damping. Hysteretic damping reached a maximum of 37% for 0.050 volume fraction of MWNT at medium strain (25%). The crosslink density measured through equilibrium swelling method revealed that the degree of ionic crosslinking decreased with increase in MWNT content, which was confirmed by infrared spectroscopy. Transmission electron microscopic images showed that agglomeration of nanotubes was prominent at higher volume fractions of MWNT. Acoustic absorption capability, as measured by the impulse method, decreased with increase in MWNT concentration. The high hysteretic damping and low acoustic absorption make the nanocomposites a superior choice for structural vibration damping in underwater acoustic sensor systems. POLYM. COMPOS., 39:E1269–E1279, 2018. © 2018 Society of Plastics Engineers

In this work, application of rubber-MWNT nanocomposite for underwater acoustic sensors is explored. The nanocomposite is developed by incorporating multiwalled carbon nanotubes (MWNT) into carboxylated nitrile rubber by mechanical mixing. The addition of MWNT up to 10 phr is found to result in about 330% increase in tensile strength, 140% increase in modulus, and 160% increase in tear strength. Transmission electron microscopy and scanning electron microscopy analyses indicate uniform dispersion of nanotubes in the rubber matrix. Dynamic mechanical analysis shows that damping at ambient temperature gradually increases with increasing filler content. This is attributed to the augmented frictional energy loss at the interface. The damping peak position shifts upward with increase in MWNT concentration, which may be gainfully used to tune to the operational frequency range of underwater acoustic sensors. Payne effect is observed at higher filler concentration due to the breakage of aggregates formed by fillerfiller interaction. The nanocomposite may find application for damping structural vibrations and thus to improve the performance of underwater acoustic sensors.