Belt process

Several recent patents describe improvements in the basic belt process. In one case a higher soHds polymerization is achieved by cooling the starting monomer until some monomer crystallizes and then introducing the resulting monomer slurry onto the belt as above. The latent heat of fusion of the monomer crystals absorbs some of the heat of polymerization, which otherwise limits the soHds content of the polymerization (87). In another patent a concave belt is described which becomes flat near the end. This change leads to improved release of polymer (88). 

In the belt process, the mixture is cast onto the belt or conveyor (high temperature polyethylene (264)) where gelling occurs (261,265). The gel is removed from the surface before syneresis, cut into smaller particles, and passed to a holding or washing tank (Fig. 14). The Hquid is removed from the precipitate using common chemical deHquefying methods, and the resulting particles ate dried in a continuous dryer. 

In the screw conveyor process, solutions of poly(vinyl acetate) and catalyst are mixed in a high intensity mixer and continuously introduced to a screw-type saponification and conveyor system (270). Downstream details are similar to those found in the belt process. 

Pastes and melts are spread as a thin film on a surface where they are dried and cooled, respectively. Subsequently scraped off to yield solid product. Drum drying, flaking, melt cooling, endless belt processing, slating, pastille formation. Drum dryers, drum flakers, endless belt systems... 

Figure 5 BASF belt process for high molar mass polyisobutene, (a) moving steel belt (b) twin-screw extruder (c) finishing unit (d) purification of flash-off ethylene. (From Ref. 18, courtesy of VCH Publishers, Weinheim.)...

SMC is a flat sheetlike compound, produced on a continuous moving belt process. The thermoset precursor is an UP-resin composed of an unsaturated polyester... 

FIGURE 4.6 Schematic of belt-processing for methanolysis of polyvinyl acetate. 

Heat sealing is commonly used with a continuous belt process for sealing plastic bags, film, etc. If the plastic film has too high a melt temperature or if it is a themoset material, thin thermoplastic films have been applied by coating or coextrusion to act as a hot-melt adhesive for seating films. A heat-sealing adhesive is a thermoplastic film adhesive that is melted between adherend surfaces by apptication of heat to one or both of the surfaces. 

In this run of our optimisation method we have identified two opportunities to parallelize actions. Within the Filling Robot process, the filling can be prepared and measured at the same time. In the conveyor belt process, it is possible to prepare... 

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