We investigate the mechanical properties of ultra-thin layers of polystyrene/poly (2-vinylpyridine) (PS/P2VP) block copolymers by means of a Surface Forces Apparatus adapted to operate as a rheometer at the molecular level. Two systems are studied: "brush/wall" and "brush/brush". A comparison of the normal force curves shows that when brushes are compressed against each other, they contract rat...

Texture of fatty liver, as a multiparameter attribute, has been examined more and more during the last decade. The instrumental texture analysers used are developed on the analogy of penetration tests to imitate the action of human jaws. In this study a Physica UDS200 rheometer was used, fitted with a MP31 top plate and a Peltier bottom plate. Rotational rheometer measurements using plate-plate...

in this paper, the flow of couple stress fluid is investigated in a helical screw rheometer (hsr). by unwrapping the channel, lands, and the outside rotating barrel, the geometry of hsr is approximated as a shallow infinite channel. both one- and two-dimensional analysis of the problem is presented using rectangular coordinates. in either case an exact solution of the flow problem is presented ...

Rheological properties related to the extrusion of polyolefins are shear viscosity, elongational slip velocity and their temperature- pressure-dependencies. These measured in rheology lab mainly via a parallel-plate rheometer capillary rheometer. Then appropriate rheological models have be used account for all these properties. Such either viscous (e.g., Cross model) or viscoelastic K-BKZ model...

Each film coating formulation and film forming polymer has an individual limiting maximum viscosity value for processability which depends on the type of nozzle and coater used, as well as on the batch size. In order to optimize efficiency and quality, knowledge of the formulation dependant viscosity curves is absolutely necessary. Fig. 1: Thermo Scientific HAAKE RotoVisco 1 rotational rheomete...

In this work, the laboratory-made handsheets having different grammages were obtained at certain production conditions. The tensile characteristics of analysed by using two measuring techniques. main method for determining behaviour was performed on universal testing machine, which is a generally accepted conventional machine. A rheometer device used as second and alternative properties handshe...

The effectiveness of natural Gilsonite on the performance properties modified bitumens was studied. Three samples having different ratios that are 6%, 8% and 10% by weight base bitumen which PG 64-16 grade were prepared. physical storage stabilities four investigated means conventional tests. short-term long-term aging processes conducted with rolling thin oven pressure vessel tests, respective...

acrylamide was grafted in low density polyethylene during melt processing in the presence of a free radical initiator using a torque rheometer in a closed system. effects of processing time, acrylamide and benzoyl peroxide concentrations were studied. ftir studies revealed that the degree of grafting increased by an increase in acrylamide concentration. maximum grafting was obtained at 7 minute...

This study treats one important aspect of starch-filled rubber compounds which is their rheological behavior. Starch-based SBR1712 masterbatches resulting from various formulations were prepared using a mini two roll mill and an internal mixer (Plastograph Brabender).The content in starch was varied from 0 to 50 phr. The effect of starch content on the rheological behavior was ev...