Processing viscosity reduction

Apple application e)q)aiments for producing ple juice show a clear benificial effect liumnogalacturonase in combination with a pectinase was added to the process. As can be seen from figure 5 rhamnogalacturonase has a clear positive influence on viscosity-reduction. Rhamnogalacturonase also prevents formation of haze in juices and therefore gives a stable juice. 

Comparison with acoustic cavitation have also shown that hydrodynamically generated cavitation is far more energy efficient i.e. 76.5 J/mL as against 14,337 J/mL needed for sonically generated cavitation, for the same process, i.e., equivalent viscosity reduction. 

Haney III, W. H., and Monticello, D. J., Microbial Process for Reduction of Petroleum Viscosity. Patent No. W09211343. 1992, July 09. 

There are also hundreds of additives used as process aids to improve such things as air release, cure rate, thickening, viscosity reduction, mold release, wetting and dispersion of fillers, thixotropy, shrinkage and static reduction. 

Plating bath viscosity can be lowered by raising the solution s temperature. This will result in reduced process solution volumes entrapped on the workpiece, and thus, less dragout. Raising the bath temperature of a water-like solution from 100° to 140°F results in a viscosity reduction of 30%. Figure 8-3 illustrates that the drag-out reduction from this temperature increment is about 17% (Meltzer 1989). 

The viscosity of a starch paste is often characterized differently by the starch manufacturer and by users in the paper industry. In the manufacturing plant, viscosity tests serve to control the starch modification process. As an example, the test is used to determine when to terminate a starch oxidation reaction for viscosity reduction. In the paper mill, viscosity testing is required to characterize the flow properties of starch-based coating formulations. 

An ingredient added to an adhesive to reduce the concentration of base resin or binder is called a diluent. Diluents are principally used to lower the viscosity and modify the processing conditions of some adhesives. The degree of viscosity reduction caused by various diluent additions to a conventional epoxy adhesive is shown in Fig. 1.5. Diluents do not evaporate as does a solvent, but they become part of the final adhesive. Reactive diluents react with the resin base during cure, so that the final adhesive characteristics are determined by the reaction product of the binder and diluent. Nonreactive diluents do not react with the resin or curing agent and, therefore, more seriously weaken the final properties. Coal and pine tar are common nonreactive diluents. 

The characteristics of lubricants, their effects during plastics processing and their influence in the calendering process are discussed in depth. Attention is paid to the different intemal/external behaviour of lubricants, viscosity reduction by internal lubricants, fusion delay by external lubricants, shear liquefaction by lubricants and the suitability of various lubricants for the manufacture of calendered PVC films in relation to melt elasticity, release effect, flow and plate-out. 

Key process and material variables are viscosity (or viscosity reduction)... 

These at room temperature plastic/hard one-component systems are usually processed in adhesive melting drum installations. Adhesive heating occurs by means of heated panels that, depending on the consumption, continuously sink in the drum and heat the adhesive in layers until the curing reaction and viscosity reduction set in. The adhesive melt is pumped to the application appliances by thermally insulated hoses that are also heated. While the melt is solidifying, the final curing occurs in the glueline and results in an adhesive layer (just like a hot-melt adhesive, Section 5.1) due to the chemical reaction described in Section 4.1.1. 

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