The adsorption of the polybutadiene terminated with a polar group on hydrophilic zeolite particles and the resulting dispersion stability were examined in non-aqueous solvents with a different solubility parameter. The amount adsorbed of the polymer with group terminations was considerably larger than that of the homopolymer. With increasing the polarity of group terminations, the amount adsorbed increased, and dispersion stability improved. For a polymer with the same polarity, the amount adsorbed was independent of the solubility parameter of the solvents. The stability effect was eluciated by the steric stabilization theory on the basis of the polymer conformation on the particles's surface.

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A rotary type of rheometer with a conical rotor has been applied to measure the flow characteristics of powders. The shearing torque as a function of the boundary area in the friction zone of the rotor was continuously measured during intrusion of the conical rotor into the powder bed.
The effects of the rotor shape and operating conditions on the torque variation curves were investigated, and an empirical coefficient C including factors of stress and internal friction coefficient was proposed to express the change in the physical properties of the powders.
The applicability of this testing method was confirmed by measuring two typical powder samples: a binary-component mixture of fine powders processed under different operating conditions, and polymer particles coated with different kinds of wax.

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A new type of powder mixer has been developed for preparing highly homogenized mixtures and composites of various particulate materials. It consists of a horizontally rotation (at low speed) elliptical barrel and an elliptical impeller (rotating at high speed) installed coaxially inside the barrel. A strong shear force acts on the powders periodically at the narrow clearance between the barrel and the rotor tip.
The effects of the operating conditions on the degree of mixing and dispersing have been investigated by using an optical method. The applicability of this equipment to the manufacturing of a variety of powder composites has been shown.

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Monodispersed, spherical MTiO₃(M=Ba, Sr, Pb) fine powders were synthesized by the hydrolysis of metal alkoxide in a mixture of alcohol and dipolar aprotic solvent. Ba-Ti, Sr-Ti or Pb-Ti double alkoxide were used as starting materials. The synthesis factor such as water and alkoxide concentration, type of solvent and reaction temperature influenced particle size, particle size distribution and the state of aggregation. Monodispersed powders were obtained when the volume ratio of octanol to acetonitrile was in the range from 60:40 to 80:20. As-prepared powders were amorphous and then crystallized to a perovskite-type structure by calcination at 600°C. Spherical morphology was retained after calcination at 600°C. Fluoresence X-ray analysis showed that the BaO/TiO₂, SrO/TiO₂ and PbO/TiO₂ ratio of as-prepared powders was 48:52, 49:51 and 49:51, respectively.

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The delamination of talc platelets was carried out by two different wet grinding methods, i. e., by a ball mill, and by a rod mill. The rate of rotation, grinding time and volume of suspension were systematically varied. The best talc platelets with a maximum aspect ratio of 42 were obtained when suspension with the solid volume fraction of 0.15 was filled to a volume of 25% of the capacity and rotated at 77rpm in a ball mill. The change in the pH of the suspension and mechanical amorphization were also observed indicating simultaneous mechanical activation.

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