Composition, rheological properties

In all cases, because of the orientation phenomenon inherent to the fiber spinning process, the phases are all aligned in the longitudinal direction. In the fibril-matrix structure, the number and size of fibrils depend on composition, rheological properties of the constiments and the type of deformation during spinning. A tree-ring structure , as shown... 

It has become common to recycle photo-oxidized polypropylene by blending it with original polypropylene [2174,2175]. However, both rheological and mechanical properties depend on composition. Rheological properties indicate some interactions between the two polymers at low shear rate. On the other hand, at high shear rates there is evidence of incomp-ability. The nominal strength is almost independent of the composition, whilst other mechanical properties are similar to those of the degraded polymer. 

The influence of the composition of asphalt has been recognized, for many years, as being an important factor in controlling the performance of such materials. Furthermore, rheological properties have always been associated with composition but, in order to utilize compositional data effectively, more definitive correlations between composition and properties are needed (46—48). 

Acrylic polymers have the advantage that they can be formulated to be inherently tacky. However, for certain applications it may be desirable to adjust the rheological properties of the PSA beyond what can be obtained by selecting the right polymer composition and crosslink density. 

Chemorheology is concerned with the chemical kinetics and the associated flow properties of a model reacting system. Energetic composite rheology is a continuously evolving process. The initial slurry viscosity is determined by the system temperature, plasticizer content... 

Indeed, one often observes a more or less direct relationship between the rheological properties of melts and the mechanical strength of the condensed material. This is a commonplace statement in regard of, say, stiffness, since the equations relating the viscosity of heterogeneous materials with their composition... 

Effect of Filler Particle Size and Shape on the Rheological Properties of Composites... 

Organotitanates form regular adsorbed layers on the filler surfaces. This assures a high degree of dispersibility of the solid particles of the filler, removal of moisture and air from the surfaces, a material improvement of the rheological properties of filled compositions. Also, it is possible to use much greater percentages of cheap... 

Popov VL (1982) Rheological properties of norplastics and composites on their basis. Candidacy thesis. Institute of Chemical Physics AN SSSR publication, Moscow... 

Fridman ML (1981) Control of rheological properties of thermoplastics and compositions on thdr basis with a view to intensify the shaping process, Doctorate thesis, IKhF AN SSSR, Moscow... 

The fact that the appearance of a wall slip at sufficiently high shear rates is a property inwardly inherent in filled polymers or an external manifestation of these properties may be discussed, but obviously, the role of this effect during the flow of compositions with a disperse filler is great. The wall slip, beginning in the region of high shear rates, was marked many times as the effect that must be taken into account in the analysis of rheological properties of filled polymer melts [24, 25], and the appearance of a slip is initiated in the entry (transitional) zone of the channel [26]. It is quite possible that in reality not a true wall slip takes place, but the formation of a low-viscosity wall layer depleted of a filler. This is most characteristic for the systems with low-viscosity binders. From the point of view of hydrodynamics, an exact mechanism of motion of a material near the wall is immaterial, since in any case it appears as a wall slip. 

Clay hllers were surface modihed with TMPTA or triethoxyvinyl silane (TEVS) followed by EB irradiation by Ray and Bhowmick [394]. Both the untreated and treated fillers were incorporated in an ethylene-octene copolymer. Mechanical, dynamic mechanical, and rheological properties of the EB-cured unfilled and filled composites were studied and a significant improvement in tensile strength, elongation at break, modulus, and tear strength was observed in the case of surface-treated clay-filled vulcanizates. Dynamic mechanical studies conducted on these systems support the above findings. 

The interfacial rheologic properties are extremely sensitive parameters toward the chemical composition of immiscible formation liquids [1053]. Therefore comparison and interpretation of the interfacial rheologic properties may contribute significantly to extension of the spectrum of the reservoir characterization, better understanding of the displacement mechanism, development of more profitable enhanced and improved oil-recovery methods, intensification of the surface technologies, optimization of the pipe line transportation, and improvement of the refinery operations [1056]. 

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