Structure architecture and morphology changes study in nylon 6/12 copolymers through anionic copolymerization via Response Surface Methodology modeling

The objective of this study was to investigate and characterize the morphology changes in nylon 6/12 with the variation of the initiation system in anionic copolymerization as well as optimization of initiation system via statistical Response Surface Methodology (RSM) modeling. At first, the random structure was directly proved through Carbon-13 (C13) nuclear magnetic resonance (C-13 NMR) analysis. However, in the course of study, considering both C-13 NMR and Proton nuclear magnetic resonance (H-1 NMR) signals, comonomer placement alteration in chain structure was realized; the higher the loading of initiator, the more hand in hand embedding of omega-laurolactam (LL) comonomers in the polymer backbone. Wide-Angle X-ray Scattering (WAXS) was performed to identify crystal structural changes with alteration of the initiator and catalyst contents, and further supported the observations. Thermal analysis performed and, the above conclusions were confirmed with Differential Scanning Calorimetry (DSC) curves too.