Preform processes direct

In one very important respect the manufacture of spiritous liquors from a grain base differs from that commencing with a fruit juice base. This difference is that the fruit juices contain preformed sugar directly available for fermentation while the cereals contain starch and proteins in a relatively insoluble form. It was stated in previous chapters that by suitable processes this insoluble starch and proteins can be converted into soluble forms which are then fermentable. The processes by which this conversion is accomplished are the subject of this chapter. 

Figure 5.6 Schematic of the direct preform process spraying two molds...

New glass fibre-reinforcement products for u.se in fibre-directed preform processes are another focus of development, designed specifically for liquid composite moulding applications such as resin transfer moulding with thermoset polyesters. 

MCVD process (Fig. 7) the reactants enter the tube, are reacted in the hot 2one of the torch, deposit therm oph oretically downstream of the torch, and are subsequendy sintered to a clear glass as the torch passes over the deposited particulate layer. Once the desired stmcture has been deposited, the direction of the torch is reversed and the tube is collapsed to form a soHd preform. 

Radiation-induced degradation reactions are in direct opposition to cross-linking or curing processes, in that the average molecular weight of the preformed polymer decreases because of chain scission and without any subsequent... 

Rotating-drum-type and belt-type heat-transfer equipment forms granular products directly from fluid pastes and melts without intermediate preforms. These processes are described in Sec. 5 as examples of indirect heat transfer to and from the solid phase. When solidification results from melt freezing, the operation is known as flaking. If evaporation occurs, solidification is by diying. 

Ionic polymers are a special class of polymeric materials having a hydrocarbon backbone containing pendant acid groups. These are then neutralized partially or fully to form salts. lonomeric TPEs are a class of ionic polymers in which properties of vulcanized rubber are combined with the ease of processing of thermoplastics. These polymers contain up to 10 mol% of ionic group. These ionomeric TPEs are typically prepared by copolymerization of a functionalized monomer with an olefinic unsamrated monomer or direct functionalization of a preformed polymer [68-71]. The methods of preparation of various ionomeric TPEs are discussed below. 

Both iron- and nickel-mediated cyclooligomerization processes have been used in direct routes to pyrrole derivatives. Preformed ferracyclopentadiene complexes can be converted in moderate yields into 2,3,4,5-tetraphenyl-... 

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