Modified Mooney method

Due to production tolerances, the pressures and, hence, the wall shear stresses differ slightly for the three different barrel diameters. Since, however, the modified Mooney method only applies to Tr = const, additional calculated values are needed for plotting the true flow curve. They are obtained via a grid of shear stresses covering the measured range and super-... 

Mooney s method has been modified in various ways to allow for the observation that, with many suspensions, the slip velocity depends on the tube diameter as well as the wall shear stress. Jastrzebski (1967) deduced that, for certain kaolinite-water suspensions, vs was inversely proportional to d Thus a modified slip coefficient Cj may be defined by... 

Surface water is the water from Mooney Mooney Dam prior to concentration and freeze drj ing, whereas NOM is the redissolved powder of the same water. A small, but nevertheless clear, increase in molecular weight can be seen. It is thus obvious that the organic is being modified even using this comparably soft concentration method. 

Three different techiuques for mixing a sihca and caibon black filled tyre tread compound were evaluated and the effect of surfactant-based process additives (modified zinc soaps and a zinc soap/resin combination designated Struktol HT 266) on productivity and compound quality investigated. Mixing methods studied involved the use of a separate filler addition stage for each component type and different orders of filler addition. Mixing efficiency and dispersion/filler interactions were examined and the effects of process additives on Mooney viseosity and extrusion assessed. The cure characteristics, physical properties and dynamic properties of the vulcanisates were also examined. 9 refs. 

---