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A considerable amount of research has been devoted to carbon nanotubes because of their unique electrical, mechanical, optical, and chemical properties. Here, in this report, we introduce a novel, simple ultraviolet initiated ''graft from'' polymerization method to synthesize PEGylated carbon nanotubes. This grafting procedure significantly enhanced nanotube aqueous dispersibility and long term stability in solution. Mass of grafted polymer chains was easily modulated by adjusting polymerization reaction time, and nanomaterials containing up to 80% polymer by weight were synthesized. Nanotube morphology was characterized by SEM, TEM before and after the functionalization. In addition, the covalent bonding of polymer chains to the nanotubes structure was elucidated by Raman, ATR-FTIR, and XPS spectroscopy.

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A method simulating the formation of densely cross-linked polymeric networks was developed that incorporates both intramolecular as well as intermolecular interactions and the subsequent effects they have on the end network structure. The all-atom nature of the model allows for the simulation of network formation in a variety of conditions including differing solvent qualities, presence of inert species, as well as nonlocal effects such as polymerization in the presence of a template molecule. We employed an all-atom kinetic gelation technique that utilized an off-lattice approach that tracked the position and interaction of all atoms throughout the simulation. This model was then used to study the formation of polymeric networks capable of recognizing and binding a specific molecule out of a host of competing species. Simulation of the imprinted network formation was done using the all-atom kinetic gelation framework, which helped identify the interactions central to recognition. These results were verified by comparison with previous experimental results.

In this work, we detail a method whereby a polymeric hydrogel layer is grafted to the negative tone photoresist SU-8 in order to improve its wettability. A photoinitiator is first immobilized on freshly prepared SU-8 samples, acting as the starting point for various surface modifications strategies. Grafting of a 2-hydroxyethylmethacrylate-based hydrogel from the SU-8 surface resulted in the reduction of the static contact angle of a water droplet from 79 ± 1° to 36 ± 1°, while addition of a poly(ethylene glycol)-rich hydrogel layer resulted in further improvement (8 ± 1°). Wettability is greatly enhanced after 30 minutes of polymerization, with a continued but more gradual decrease in contact angle up to approximately 50 minutes. Hydrogel formation is triggered by exposure to UV irradiation, allowing for the formation of photopatterned structures using existing photolithographic techniques.