Thickeners performance

Stable thickener performance can be maintained by carefully monitoring operating conditions, particularly the pulp interface level and the underflow rate and concentration. As process changes occur, the pulp level can vary regulation of the underflow pumping rate will... 

B. Fitch, Batch Tests Predict Thickener Performance, Chem. Eng., 78(19) 83 (1971),... 

Alkanolamides that are liquid at room temperature have been commercialized based on increased content of unsaturated C18 acids, use of branched alkanolamines such as monoisopropa-nolamine (MIPA), or propoxylation of MEA amides, as well as blends of all these with PEG esters to improve thickening performance of the products. The higher cost of the earlier-mentioned feedstocks... 

Sobisch T, Lerche L (2008) Thickener performance. Colloids Surf A 331 114... 

Features Improves thickener performance, imparts exc. pH stability, reduces corrosion problems effective in low-odor systems replacement for ammonia... 

The dimensions of alginate chains (radius of gyration and intrinsic viscosity) in aqueous solutions depend on the external salt concentration the expansion is directly related to the persistence length Lp and to the thickening performance of the polymer. The relative extension of the three types of blocks increases in the following order ... 

Farrow, J B, Fawell, P D, Johnston, R R M, Nguyen, T B, Rudman, M, Simic, K and Swift, J D (2000), Recent developments in techniques and methodologies for improving thickener performance . Chemical Engineering Journal, 80(1-3) 149-155. 

L. Svarovsky and A. J. Walker, "The Effect of Eeed Thickening on the Performance of a Horizontal Vacuum Belt Eilter," 1st World Congress Particle Technolog)/, Part IV, 331 Event of EFCE, Apr. 16—18, 1986, NMAmbH, Ni>mburg, Germany, 1986. 

Addition Point. The flocculant addition point in a continuous system can also have a significant effect on flocculant performance. The turbulence as the flocculant is mixed in and the floes travel toward the point where they enter the thickener or filter causes both the formation and breakup of floes. Usually there is an optimal addition point or points which have to be determined empirically. In cases where the same polymer is being added at two or more points, the relative amounts added at each point may also affect performance. Thus providing multiple addition points in the design of new installations is recommended (56). 

Synthetic lubricants are made with neopentyl glycol in the base-stock polyester (24). Excellent thermal stabiHty and viscosity control are imparted to special high performance aviation lubricants by the inclusion of polyester thickening agents made from neopentyl glycol (25,26) (see LUBRICATION AND lubricants). Neopentyl glycol is also used to manufacture polymeric plasticizers that exhibit the improved thermal, hydrolytic, and uv stabiHty necessary for use in some exterior appHcations (27). 

High Water-Base Fluids. These water-base fluids have very high fire resistance because as Httle as 5% of the fluid is combustible. Water alone, however, lacks several important quaUties as a hydrauHc fluid. The viscosity is so low that it has Httle value as a sealing fluid water has Httle or no abiHty to prevent wear or reduce friction under boundary-lubrication conditions and water cannot prevent mst. These shortcomings can be alleviated in part by use of suitable additives. Several types of high water-based fluids commercially available are soluble oils, ie, od-in-water emulsions microemulsions tme water solutions, called synthetics and thickened microemulsions. These last have viscosity and performance characteristics similar to other types of hydrauHc fluids. 

In drafting a patent appHcation, proceeding methodically through the several steps necessary to produce the type of disclosure legally and technically sufficient to satisfy the requirements of the laws of the United States is absolutely essential to a successful granting of the patent. A first step is to outHne those elements of the invention which are absolutely essential to its practice. A body of disclosure should be outlined for each of the essential elements of the claim. This disclosure should describe each element in terms of its function, as weU as the parameters that are relevant to the essential nature of the individual element. For example, if a chemical mixture has a component which acts so as to thicken the mixture, it is appropriate to outHne the family of constituents that can serve this function. At the same time, a full outHne of the disclosure of this individual element will include mention of those chemicals that are preferred for use within the mixture so as to perform the desired thickening function. 

Resin Solubilizers. In general, water-soluble resins ate amine salts of acidic polymers. Water-soluble coatings formulated with AMP-95 and DMAMP-80 exhibit superior performance (15,16) (see Water-SOLUBLE polymers). AMP-95, used in conjunction with associative thickeners (17) or hydroxy-ethylceUulose, provides for the most efficient utilization of such thickeners. It also is the neutralizer of choice for use with hair spray resins. 

The viscosity of an adhesive directly influences its penetration into a substrate as the viscosity increases, the penetrating power decreases. It also determines the amount of mileage or spread that can be obtained. An optimum viscosity exists for each substrate and each set of machine conditions and must be achieved in order to manufacture an efficient adhesive. Poly(vinyl acetate) emulsions are frequently too low in viscosity to be metered efficiently or to perform well as adhesives by themselves. They must be bodied to working viscosities, eg, by adding thickeners. 

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