Preparation and processing of porous sulfur foams having low thermal conductivity

Porous sulfur foams were prepared by combining inverse vulcanization and template removal techniques. The porosity of the foam was altered by varying the template particle size; which lead to drop in thermal conductivity.

Block, random and palm-tree amphiphilic fluorinated copolymers: controlled synthesis, surface activity and use as dispersion polymerization stabilizers

The architecture of novel fluorinated copolymers drastically influences their stabilizing properties and their ability to template particle formation.

Study on the Mechanical Properties of PP/EPDM/Mesoporous MCM-41 Composites

Nano-sized as-synthesized MCM-41 (with template) particle, whose pore channels and outer surface are full of organic CTAB template, is used as compatibilizers for immiscible polypropylene (PP)/ethylene–propylene–diene terpolymer (EPDM) blends. The mechanical properties of PP/EPDM/mesoporous MCM-41 ternary composites are investigated. The nano-structured MCM-41 (without template) material constituted by an ordered network of hexagonal channels is selected to compare with as-synthesized MCM-41 (with template) in mechanical properties of PP/EPDM blend. The results shows that tensile strength of the blend is increased by 13.6% and the impact strength is increased by 71.6% by addition 2 wt% content of as-synthesized MCM-41 (with template) compared to pure PP/EPDM. The presence of MCM-41(without template) in the blend cannot improve the mechanical properties obviously. SEM reveals that the enhancement of the interface is obtained by adding MCM-41 (with template). SEM also indicates that incorporation of as-synthesized MCM-41 (with template) into PP/EPDM blend can act as compatibilizer, which results in a decreased particle size of dispersion phase together with morphological evidence of interfacial adhesion. However, with the presence of MCM-41 (without template), the interface do not show clearly change compared with the PP/EPDM blend. The PP/EPDM/MCM-41 (with template) composites show higher tensile strength and impact strength than the PP /EPDM / MCM-41 (without template).

Parametric Studies on the Processing Parameters of a Thermally Wicking Material using Image Analysis

A heat pipe is a device that transports heat against gravity using a wicking material and evaporation-condensation cycle..In these systems a thermal wick moves fluid from the cool region of a heat pipe to the hot region, where evaporative cooling occurs. Due to the operating demands of a thermal wick, several microstructural features are integral to the performance of the wick: capillary radii, specific surface area and permeability. Measuring these properties of a thermal wick (capillary radii, specific surface area and permeability) is difficult, therefore image analysis methods of quantification of the critical properties of a thermal wick has been developed . However, the microstructure of a thermal wick contains semicontinuous pores, therefore connectivity of pores cannot be assumed during quantification of the critical properties.. Two processing parameters, sacrificial template particle size and sintering temperature, were varied during the thermal wick synthesis. Quantification of the critical properties of the thermal wick was performed using the newly developed method. The newly developed method was able to detect the an increase in the pore connectivity as the sintering temperature decreased, and an increase in the connectivity as the sacrificial template particle size decreased. The newly developed method was also able to describe the size distribution of individual pores as well as the hydraulic resistance and orientation of individual pores as well as estimate the porosity and true specific surface area of the different samples.

Effect of Template Particle Formation on Texture Development in Bi0.5Na0.5TiO3 Ceramics

The factor determining texture development was examined for Bi0.5Na0.5TiO3 ceramics made by the reactive-templated grain growth process using platelike Bi4Ti3O12 particles as reactive template. Platelike, skeleton Bi0.5Na0.5TiO3 particles were formed by the reaction between Bi4Ti3O12 and Na2CO3 in calcined compacts. Coalescence of small grains in the skeleton particles to form single template particles was important to obtain highly textured ceramics.

Selfassembling around Templates – Creating Nano Dots and Pits for Chemical Sensing –

Nano- and micro-structured materials are a powerful tool in the development of chemical sensors. Surface imprinting of different biogenous species into pre-polymerized, highly crosslinked reaction mixtures (polyurethanes, polystyrenes, sol-gel materials etc.) yields selfassembled structures that are optimized to re-incorporate the template particle. Surface properties are tuned both on the micrometer as well as the molecular scale, as selectivity studies suggest the formation of strongly adapted interaction networks between the polymer and the species used for imprinting.