Abstract: Polymer extruded or expanded foams that contain modifier-free nanoclays are provided. The addition of modifier-free nano-clays to extruded or expanded foam products improves the thermal properties, mechanical properties, and fire performance properties. Water or a water-containing compound is used as a carrier for the modifier-free nanoclays. The final foamed products may be utilized in building application such as foamed insulation products and in underground applications such as highway insulation. A preferred modifier-free nanoclay is Na+MMT. Modifier-free nanoclay particles may be injected into a polymer during an extrusion foaming process. In another embodiment of the invention, polymer beads containing water/nanoclay particles are formed using inverse emulsion/suspension polymerizations and expanded or extruded into a foamed product. In a further embodiment, a modifier-free nanoclay particle is encapsulated in a super-absorbent material, which may be used in an expanding or extruding process.

Abstract: With extraordinary mechanical properties, carbon nanofibers (CNF) serve as reinforcements for both lightweight and ultra strong composite materials. CNF was used as the reinforcing nanoelements to synthesize polystyrene (PS)/CNF nanocomposites by the in-situ polymerization process. The obtained composites were further foamed using supercritical CO2 as the foaming agent. A homogeneous dispersion of CNF was observed and the final PS/CNF nanocomposite foam showed microcellular foam morphology.

Abstract: A valve is provided for use in a microfluidic platform. The valve is preferably a superhydrophobic fishbone valve that comprises a channel and at least one branch in continuous contact with the channel. The channel has two sidewalls, an inlet, and an outlet. The branch extends outwardly and substantially perpendicularly from each sidewall of the channel. In further embodiments, the number of branches is from one to five. The sidewalls and the walls of the branch(es) preferably have a fluorine coating. The valve retains superhydrophobicity even after exposure to a protein solution.

Abstract: An interferometer system for measuring a displacement along a first direction includes (1) a measurement roof optic (e.g., a porro prism) mounted to a stage translatable along the first direction, (2) a polarizing beam splitter having (a) a first face opposite the measurement roof optic and (b) a second face opposite the first face, (3) a first wave plate located between the measurement roof optic and the first face of the polarizing beam splitter, and (4) a redirecting optic located opposite the first face of the polarizing beam splitter. A measurement path through the system includes only segments located substantially in a plane defined by the first direction and a second direction orthogonal to the first direction.

Abstract: A method of bonding materials. The method comprises providing a polymer; providing a second material; contacting the polymer and the second material at a low contact pressure in the absence of a solvent or an adhesive; maintaining the polymer at a temperature less than a bulk Tg of the polymer; introducing a gas at low pressure; and bonding the polymer and the second material.

Abstract: Nano-sized particles such as nano-clays can be mixed with polymers through either melt compounding or in-situ polymerization. By modifying the particle surface with various surfactants and controlling processing conditions, we are able to achieve either intercalated (partial dispersion) or exfoliated (full dispersion) nano-clay distribution in polymers with the clay content up to 35% by weight. When a blowing agent is injected into the nanocomposite in an extruder (a continuous mixer) or a batch mixer, polymeric foam can be produced. Supercritical carbon dioxide, an environmentally friendly, low-cost, non-flammable, chemically benign gas is used as the blowing agent. This process forms a microcellular foam with very high cell density (>109 cells/cc) and small cell size (<5 microns) can be achieved by controlling the CO2 content, melt and die temperature, and pressure drop rate.