Nanoscale materials are typically produced either by breaking down larger structures or by assembling them directly from their smaller constituents. Another approach is to establish processing conditions where initially large component domains in the melt intermingle via intelligent agitations in accordance with continuum mechanics, refine progressively, and eventually give nanoscale materials where molecular interactions may induce further orientation. In this paper, the potential of chaotic advection to develop in situ nanoscale structures is specifically described in polymer melts. Due to induced chaotic motions, melt domains stretch and fold recursively. Structure is evolved in lieu of being broken down as occurs typically in common blending. Moreover, the extent of structure development is controllable so that a variety of distinct material arrangements can be formed.

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Wound healing is a dynamic and complex process that requires a suitable environment to enhance the rapid healing process. In this context, fabrications of nanofibrous materials with antibiotic and antibacterial properties are becoming extremely important. In this present work, we report on the fabrication and characterization of electrospun cellulose ether-PVA nanofiber mats loaded with halloysite clay (HNT) and gentamicin sulfate (GS) for faster wound healing applications. The morphology of nanofiber mats was examined by SEM and TEM. The average diameter of the nanofiber mats were in the range of 325 ± 30 nm. The physicochemical characterizations were done by FT-IR and XRD, which reveal the presence of HNT and GS into the nanofibers. The incorporation of halloysite gave good mechanical strength to the nanofiber mats. Swelling studies indicated the hydrophilicity of the mats. In vitro studies revealed that HNTs are nontoxic to L929 fibroblast cells and also promote cell growth and proliferation. The antibacterial property of HNT was also studied. The slow release of GS from the nanofiber mats was observed for a period of 18 days. The in vivo wound healing studies on the wistar rats for 21 days revealed the wound healing faster within 2 weeks by the incorporation of HNT and GS into the nanofiber mats and hence these nanofiber mats show great potential in acute and chronic wound healing applications.

A totally new mode of frontal polymerization (FP) of acrylamide is established which is triggered by the simple addition of a minute, specific volume of water. Experimental conditions under which this mode of polymerization yields linear and water‐soluble polyacrylamide were carefully established, paving the way to synthesize commercially pertinent homo‐ and copolymers. A new redox couple was identified to circumvent the imidization and the ensuing gelation, hitherto associated with FP of acrylamide. Effects of reaction variables such as type and concentration of redox couple and volume of water on measurable parameters of FP such as front velocity, front temperature, shape of front and yield have been studied. Two types of redox couples are reported. Nonplanar frontal regime was observed in few redox couples. We could visually observe helical patterns with naked eyes, while layered patterns were observable under SEM. Additionally, micro‐phase separation and heterogeneity in the polymer matrix was observed due to unreacted pockets of monomer which evolve via bulk mode. This nonlinear phenomenon is described.magnified image