Materials processing industry particulate systems

The size distribution of particles in a wide variety of particulate systems is of paramount importance in the chemical processing industries. For example, the compacting and sintering behavior of metallurgical powders, the flow characteristics of granular material, the hiding power of paint (qv) pigments (qv), and the combustion efficiency of powdered coal (qv) and sprayed fluids, are all heavily influenced by the size of the constituent particles (see Flow... 

UPE resins can be used as clear castings or in combination with particulate fillers or fibres. The resin was developed to meet the demand of lightweight materials in military application. The first functional use of UPE was in radome. Because of the obvious advantages of easy processability and low cost, it was used in a wide range of applications in civil sectors such as tanks, pipes, and electronic gears. Some of the important products based on cast UPE resins are encapsulation of electronic assembly, buttons, door handles, knives, umbrellas, industrial wood and furniture finishing. A filled resin system using limestone, silica, and china clay are used for floor tiles. The major use of UPE is as a matrix for fibre-reinforced composites. Such composites have wide applications in automobile and construction industries such as boats, water-skis and television antennae. Examples of applications of UPE resins are presented in Table 2.7. 

From its onset, the semiconductor industry has relied on fluoropolymers as the material of construction for wet processing equipment, fluid transport systems, and wafer handling tools. Semiconductor manufacturing processes are extremely intolerant of particulate and chemical contamination which can, even in trace amounts, cause severe decreases in yields. Therefore, fluoropolymers purity and resistance to chemical attack have created an important role for plastics in the semicon industry. In the next section, we briefly review the chip manufacturing industry to provide the reader with a more in-depth understanding of the important role that fluoroplastics play in this industry. 

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