Unidirectional compression of electrorheological fluids in electric fields

A series of unidirectional compression tests on electrorheological fluids has been carried out with different plate sizes, initial plate separations, and applied voltages. Experimental results of compression pressure were compared with the continuum non-Newtonian squeeze-flow theory in a normalized form. It was found that the compression resistance of the electrorheological fluid in an electric field was much higher than that predicted by the theory when the fluid was compressed to some extent and/or when the initial plate separation was relatively small. Characteristics of the pressure variation with the reduction in electrode gap width have been analyzed, and the compression behaviors under different experimental conditions have been discussed in terms of the morphology of particle aggregations under compression.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/87377/2/074901_1.pd

The effects of different additives on the dielectric relaxation and the dynamic mechanical properties of urethane dimethacrylate

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/73548/1/j.1365-2842.2000.00491.x.pd

The effects of moisture on the dielectric relaxation of urethane dimethacrylate polymer and composites

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/75059/1/j.1365-2842.2001.00669.x.pd

Thermoelastic effect in liquid mercury at high hydrostatic pressures

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/43034/1/10855_2005_Article_BF01672058.pd

Thermal effects in styrene-butadiene rubber at high hydrostatic pressures

The temperature changes as a result of rapid hydrostatic pressure applications are reported for unvulcanized styrene-butadiene rubber (SBR) in the reference temperature range from 292 to 405 K and in the pressure range from 13.8 to 200 MN m-2. The thermal effects were found to be a function of pressure and temperature. A curve fitting analysis showed that the empirical curve ([part]T/[part]P)=ab([Delta]P)b-1, described the experimental thermoelastic coefficients obtained from the experiments. The data were analysed by determining the predicted thermoelastic coefficients derived from the Thomson equation ([part]T/[part]P)=[alpha]To/[varrho]Cp. The experimental and the predicted Gruneisen parameter [gamma]T were also estimated. Close agreement was found at low pressure but differences were observed at higher pressures between the experimental and expected values for the thermoelastic coefficients and the Gruneisen parameter.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/25970/1/0000036.pd

Similarities in the fracture surface features of borosilicate and polymer glasses

Considerable similarity exists between the features on the fracture surfaces of a borosilicate glass and those on the fracture surfaces of polymer thermoset glasses like epoxies and vinyl esters. These features include the steps and welts of the hackle, the arrays of skewed cracks, and the basic longitudinal texture. It was the latter, the basic longitudinal texture, that was the most surprising find on the fracture surfaces of borosilicate glass. On the fracture surfaces of polymer thermoset glasses, the basic longitudinal texture has been interpreted as a remnant from the fracturing process, arising from an instability in the meniscus between air and a polymer layer softened or “liquified” by the stresses of cracking. The meniscus instability results in an array of crack fingers preceding the nominal crack front. By analogy, it is suggested that the borosilicate glass fractures by a similar process, including the softening of the glass ahead of the crack front. The basic longitudinal texture is usually visible only at high magnification and often requires (a necessity for the borosilicate glass fracture surface) the tilting of the normal to the fracture surface toward the detector. The steps, welts and arrays of skewed cracks are simply explained with the crack fingering hypothesis.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/44692/1/10853_2006_Article_BF02385750.pd

Character of adsorbed bovine serum albumin from adsorption enthalpies

Heats of adsorption of BSA onto polystyrene and polycarbonate were determined microcalorimetrically. The polymers were coated onto 50 nm alumina particles which were immersed in buffer for the measurements. Experimental variations to isolate the various component reactions of the integral heats included adsorption of native and denatured BSA from solution, adsorption onto substrates precoated with BSA, varying the thicknesses of adsorbed BSA by varying concentrations of the adsorbing solutions, and determining the denaturation energy by solution of the solid native and denatured BSA into a denaturing solvent.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/26061/1/0000135.pd

Polyurethane Elastomers as Maxillofacial Prosthetic Materials

A series of polyurethane elastomers based on an aliphatic diisocyanate and a polyether macroglycol was polymerized with various crosslink densities and OH/NCO ratios. Stoichiometries yielding between 8,600 and 12,900 gm/ mole/crosslink and an OH/NCO ratio of 1.1 resulted in polymers with the low modulus, yet high strength and elongation necessary for maxillofacial applications.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/68299/2/10.1177_00220345780570040501.pd

ISOTHERMAL ENTHALPY AND DENSITY STUDIES OF POLYMERIC GLASSES VERSUS FORMATION PARAMETERS

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/74075/1/j.1749-6632.1981.tb55672.x.pd

Thermoelastic temperature changes in poly(methyl methacrylate) at high hydrostatic pressure: Experimental

Temperature changes as a result of large rapid hydrostatic pressure changes were measured for poly(methyl methacrylate) at various temperatures from ambient to 95 °C and for various pressure increments from 14 to 207 MN/m2. We observe complete reversibility of the measurements over the pressure range studied. The value of the incremental ratio ΔT/ΔP was a function of both temperature and pressure, ranging from 0.04 to 0.09 K/MNm−2 from 298 to 368 K at low pressures, and 0.03–0.05 at 200 MN/m2 over the same temperature range. The largest variation of ΔT/ΔP with pressure was at low pressures, the ratio becoming nearly constant above about 200 MN/M2.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/69688/2/JAPIAU-53-10-6536-1.pd