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Surface structure, obtained from atomic force microscopy and X-ray reflectivity, and surface chemical analysis data, obtained from X-ray photoelectron and static secondary ion mass spectroscopy, are reported for blends of poly(p-bromostyrene) with poly(deuteriostyrene). When high speeds are used in the spin-coating process, the atomic force microscopy measurements reveal that the surface structure consists of islands, the distribution and number changing with the poly(bromostyrene) content. A ribbon structure is observed at just above 50% (w/w) poly(bromostyrene) in the mixture. These ribbons merge to form more continuous structures, leaving voids at higher concentrations. X-ray reflectivity data from the films were consistent with the topographical features observed with the AFM. At low spinning speeds, continuous films with little or no topographical structure are formed. The islands observed at high spinning speeds are predominately poly(bromostyrene) and reflect the importance of thermodynamic and kinetic driving forces in their formation.

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A series of tensile tests were conducted on a Lloyd LRX tensile testing machine for numerous natural fibers deemed potential candidates for development in composite applications. The tensile tests were conducted on the fibers jute, kenaf, flax, abaca, sisal, hemp, and coir for samples exposed to moisture conditions of (1) room temperature and humidity, (2) 65% moisture content, (3) 90% moisture content, and (4) soaked fiber. These seven fibers were then tested for the four conditions and the mechanical properties of tensile strength, tensile strain to failure, and Young's modulus were calculated for the results. These results were then compared and verified with those from the literature, with some of the fibers showing distinctly promising potential. Additionally, a study on the effect of alkalization using 3% NaOH solution was carried out on flax, kenaf, abaca, and sisal to observe impact that this common fiber pre-treatment process has on fiber mechanical properties. The result of the investigation indicated that over treatment of natural fibers using NaOH could have a negative effect on the base fiber properties. It is consequently apparent that a treatment time of less than 10 min is sufficient to remove hemicelluloses and to give the optimum effect.