Multi-lobe particle

The particle morphology can have important ramifications for the latex product performance. Because multi-lobed particles have a larger hydrodynamic volume than a spherical particle of equal polymer mass, such types of latexes have been used to raise the viscosity in coatings applications. Hollow particles are used in paper coatings to improve the optical properties and surface smoothness. Particles with core-shell morphologies or with domains have been developed for impact modification. In addition, various microencapsulation techniques have been employed to enclose a wide variety of materials (47, 97,239) for pharmaceutical, agricultural and cosmetic applications. 

Catalysts are manufactured by various methods (such as precipitation, extrusion and spray drying) in the form of cylinders, rings, multi-lobed extru-dates and other shapes. They range in size from a few millimetres to several centimetres small spheres are used in fluidized bed reactors. Active phases can be dispersed on the pre-shaped support by several methods such as by impregnation of a solution of the active components. Alternatively the catalysts can be made by the extrusion of mixtures of solid components the support, active phase, and binder. For some reactions that are diffusion limited, the catalyt-ically active species are not uniformly distributed instead they are deposited on the outer shell of the catalyst particle (egg-shell catalysts), since those inside the particle cannot be involved in the reaction. 

Similar filtration efficiency benefits may be obtained by applying a layer of fibres with irregular or multi-lobed cross-sectional shape as, for a given count, these also provide a greater surface filtration area. P84 is such a fibre, and is often used where superior particle capture is required. 

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