Simultaneous wide- and small- angle X-ray scattering (WAXS-SAXS) has revealed a stress-induced bimodal orientation of POSS crystals and PCL chains, both in a constrained POSS/PCL crosslinked network architecture with shape memory properties. POSS/PCL nanocomposites with molecular weight of 2,600 g/mol exhibiting shape memory behavior were synthesized and variation of crosslinker molar ratio was used to obtain POSS/PCL networks with different crosslink density (Alvarado-Tenorio et al., Macromolecules, 44, 5682, 2011). In that study it was shown that there are POSS crystals embedded in an amorphous PCL matrix, and the POSS crystals were ordered in a cubic nanostructure. In this work, it will be shown that elongation at room temperature of all the networks yielded a double-induced orientation (90º and 180º) of the POSS crystals, as indicated by the 101 reflection. Moreover, it was also detected stretched-induced crystallization of the otherwise amorphous PCL chains. Furthermore, SAXS data showed long periods in the meridional and equatorial orientations of 630 Å, 90 Å and 45 Å corresponding to a lamellar nanostructure of PCL chains. The induced bimodal orientation of the POSS-PCL molecular network will be correlated with its shape memory properties.

Nanostructure templates fabrication from P(S-b-MMA) thin films requires precise control of interfacial energies to achieve perpendicular orientation of microdomains to the substrate surface and can be obtained by modifying the oxide layer on silicon with a covalently anchored hydroxyl-terminated random copolymer P(S-r-MMA) termed a “neutral brush”. This commonly employed method enables precise fine-tuning of interfacial energies, but involves a lengthy process, requires starting materials that are commercially available but expensive, and results in a relatively thick under layer that can interfere with subsequent surface processing. We report here the microphase separation behaviour of an asymmetric P(S-b-MMA) diblock copolymer on electronic substrates modified with ethylene glycol (EG) self-assembled monolayer (SAM) as alternative to standard random copolymer brush. The diblock copolymer films deposited on EG SAMs upon thermal annealing spontaneously generates features with sub-lithographic resolution and pitch with perpendicular orientation. Selective etching provides a rapid route for the generation of PS template structures as the PMMA domains are etched at a faster rate. These templates can subsequently be used as etch masks to generate nanoscale features. We use state of the art lithography to generate sub-μm features and within these generate nm sized copolymer templates. Graphoepitaxy method proved a successful approach for the alignment of the microphase separated structures. This method of EG SAM driven self-0assembly provides a simple, rapid, yet tuneable approach for surface neutralization and nanofabrication technique for creating high density nanoscale features for the nanoelectronic industry.

Bottom-up design of materials via self-assembly with appropriate building blocks offers the possibility of developing innovative three-dimensional all synthetic materials with new functionalities. Helical optically active poly(3-methyl-4-vinylpyridine)/(R) and (S) mandelic acid and helical optically active poly(3-methyl-4-vinylpyridine) (P3M4VP)/ D- and L- amino acid complexes have been prepared. A diblock copolymer of helical poly[(3-methyl-4-vinylprydine)/mandelic acid complex]-block-poly(styrene) has been processed into smectic layer-like helical-bundle structures on silicon wafer. Additionally, optically active helical poly(2-methoxystyrene) (P2PMS) has been synthesized and the surfaces of the chiral helical P2MS have been shown to be effective as supports for mouse and human osteoblast cells. The cell attachment and growth data demonstrate that the chiral P2MS surfaces were better supports compared to achiral P2MS surfaces.

Silver nanoparticles (AgNPs) in silicate clay matrix films were fabricated from solution casting method. The Ag/clay dispersion was first prepared from in situ reduction of silver nitrate in the presence of silicate clay platelets and ethanol as the reducing agent. The morphologies of AgNPs have changed in a hierarchical manner, from sphere to cube and then to rod and wire morphologies during the annealing at 200 °C. The originally homogeneous AgNPs distribution in the clay matrix underwent the transformation of AgNPs in moving to the film surface and coalescing to larger sizes. The hierarchical change continued to form other morphologies. We observed the self-assembled morphologies including spherical (diameter ∼ 50 nm), cubic (length ∼100 nm), rod-like (length ∼ 1.6 μm and width ∼300 nm) and then to lengthy wire Ag (length ∼10μm). The kinetic mobility of AgNPs to surface and the characterization of Ag composition were confirmed through energy-dispersive X-ray spectroscopy (EDS) and X-ray diffraction (XRD).