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This review is designed to be a comprehensive source for polyamide (PA) nanocomposite research, including fundamental structure/property relationships, manufacturing techniques, and applications of these materials. This work presents the scientific framework for the advances in PA nanocomposite containing carbon nanofiller, and different methods applied in order to synthesis them. This review focuses on the scientific principles and mechanisms in relation to the methods of processing and manufacturing. A comprehensive discussion on technology, modeling, characterization, processing, manufacturing, and applications have been done. The processing and properties of PA nanocomposites with carbon nanofillers are investigated. In addition, the mechanical properties and morphology changes of PA with the incorporation of nanoparticles are described. POLYM. ENG. SCI., 57:475-494, 2017.

This work aims at investigating the dynamic mechanical properties of in situ anionic ring opening polymerized polyamide 12 in the presence of multi‐walled carbon nanotubes (MWCNT). According to the dynamic mechanical thermal analysis results, the addition of only 0.1 wt.% of MWCNTs led to 30% enhancement in modulus at room temperature which exhibited improved mechanical behavior of the nanocomposites. Test results showed that by the presence of 1.2% wt MWCNTs, the modulus is almost doubled, and it did not show any tangible changes by the addition of more nanotubes. Also, the effect of different frequencies on the viscoelastic behavior was investigated in order to determine the thermal transitions occurred in the synthesized nanocomposites. After that, the crystallinity of the samples has been studied using differential scanning calorimetry and X‐ray diffraction data in order to investigate the effect of MWCNT content on the crystals' dimension.

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In this work, in-situ polymerisation of laurolactam in the presence of multi-walled carbon nanotube (MWCNT) was performed toward MWCNT/Nylon12 nanocomposite. Different levels of MWCNT (0.1, 0.3, 0.7, 1.2 and 3.5 wt%) were introduced to the monomer in the presence of 2 wt% toluene diisocyanate and 1 wt% sodium caprolactam as an activator and catalyst, respectively. The test results indicated that by increasing the amount of MWCNT, the conductivity of the nanocomposite increased up to that level at which it could serve as an electrically conductive material at room temperature. The melt rheological measurements showed a transition from liquid-like to solid-like state. The rheological results obtained within the linear viscoelastic region demonstrated that the rheological percolation threshold happened at 0.1 wt% multi-walled nanotube (MWNT), whereas the electrical percolation threshold appeared at 1.2 wt% MWCNT. A homogeneous dispersion of MWCNT into the Nylon12 matrix with a high aspect ratio of MWNT was achieved at a low percolation threshold. This mainly could be attributed to the fact that a denser MWCNT network was required for electrical conductivity, while a less dense MWCNT network sufficiently impeded Nylon12 chain mobility related to the rheological percolation threshold.

In the present paper, in situ ring opening anionic polymerization of laurolactam towards polyamide 12 (PA12) was investigated, during reactive melt blending. The reaction was taken place in an internal mixer, in the presence of sodium caprolactam (catalyst), and toluene diisocyanate (activator). The effect of catalyst and activator contents on initiation time of the reaction and the residual monomer was carried out in this study. Solvent extraction method was used in order to remove the residual monomer. The experimentation is further undergone to statistical analysis to extract the absolute optimal values of activator-catalyst content in synthesized polyamide 12. Two-factor design in Response Surface Method (RMS) is suitably applied for validation analysis of experimental data. The optimum content of catalyst and activator was obtained 2.53% and 1.15%, which offers the polyamide 12 with minimum residual monomer equal to 1.26%.