LABORATORY EVALUATION OF RESIN

The total exchange capacity, the porosity, the operating capacity and the efficiency of regeneration need to be evaluated in the laboratory when comparing resins for a given application. 

The total exchange capacity is usually determined by titrating the resin with a solution of acid or base to a specific end point. This type of information is readily available fi om the manufacturers of commercial ion exchange resins. 

The pore size of a microporous resin can be determined using water soluble standards, such as those listed in Table Ifthe resin is made with 

Convert the ion exchange resin to the desired ionic form. 

Add 500 ml of water-moist resin to a round bottom flask with an aspirator. Add one liter of anhydrous isopropyl alcohol and boil under reflux at atmospheric pressure for one hour, then remove the liquid. Repeat the isopropyl addition, boiling and aspirating four times. After this procedure the resin will contain less than 0.1% water. 

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Brown and Fessler have conducted a laboratory evaluation of conductive mastics that can be brushed or sprayed onto the concrete surface to achieve the necessary thickness. However, the most extensive study on conductive paints for cathodic protection purposes has been undertaken by the Federal Highway AuthorityA total of nine commercially available resins were evaluated in this work. It was shown that neither thermal cycling, freeze thawing nor the application of cathodic protection currents... 

Mainz, Germany, 4th-5th Nov.1997, p.65-85. 6124 LABORATORY EVALUATION OF METALLOCENE RESINS IN CROSSLINKED POLYETHYLENE (XLPE) FOAM HeckRL... 

Figure 20. Equipment for laboratory evaluation of ion exchange resins.

Kakaboura, A.I., Eliades, G.C., and Palaghias, G. (1996) Laboratory evaluation of three visible light-cured resinous liners. J. Dent., 24 (3),... 

With the diversity of resins being studied in this laboratory a set of standardized testing techniques have been adopted. Generally only limited quantities of each resin are available for preliminary evaluation. Therefore, tests have been developed to yield as much useful data as possible from fifty grams of sanqile and are described in more detail elsevdiere... 

Koenst, J. W. and W. R. Herald, Evaluation of New Macroporous Resins for the Removal of Uranium and Plutonium from Waste Streams, MLM-2320, Monsanto Research Corporation, Mound Laboratory, Miamisburg, Ohio 1976. 

MJ Rocheleau, BB Sithole, LH Allen, S Iverson, R Earrell, Y Noel. Eungal treatment of aspen chips for wood resin reduction A laboratory evaluation. J Pulp Pap Sci 24(2) 37-42, 1998. 

In addition to resin development it was necessary to build a mock-up production line, to design spacing devices, to evaluate heaters, to recommend an automatic dispenser, to purchase and modify this equipment, and to put on laboratory demonstrations exhibiting the mass production feasibility of the resin system. Then, when the time came for in-plant trials, equipment setup and operation, and evaluation of the end product required similar mutually benefiting cooperation. Today we have a product, D.E.R. 741, and some of your television sets have a new look this year. This could not have happened if the several companies had not had many technical service tools to do the job. 

All HIDM and twin screw color concentrate samples were letdown into blown film for evaluation of color, strength and dispersion quality. Standard 1.5 mil (37 pm) films were prepared by blending concentrate samples with 1.0 MI LLDPE resin at a letdown of 5.0 weight percent and extruding through a 37.5 mm laboratory film line at a blowup ratio of 2.4 1 and lay flat width of 20 cm. Standard operating procedures were observed throughout. 

Morgan undertook evaluation of carbon fibers produced in Courtauld s research laboratories. He established procedures to coat carbon fibers with metals using electroless plating techniques and developed a surface treatment process to improve the bond of carbon fibers to epoxy resins. 

Two types of paint systems were used for experiments. First system used was zinc phosphate primer (50 % Zn as compound) with micaceous iron oxide (MIO) as intermediate coat followed by polyurethane (PU) as top coat denoted as ZP. Other system used was zinc rich primer (80 % Zn as dust) with MIO as intermediate coat and PU as top coat denoted as ZR. This system is costlier with respect to ZP and considered for laboratory evaluations purpose only. ZP is designed with respect to places where test panels are deployed for exposure based on manufacturers catalogues and standards [4]. These systems possess good resistance from water permeability, weathering, abrasion and good adhesion to maintain a proper barrier to the environment. The drying mechanism of the systems is the reaction between epoxy resin and polyamide. The details of each paint system used comprising primer, intermediate and top coats with the respective layer of film thickness are shown in Table 2.2. 

Chilworth has an international research and laboratory testing facilities with state of the art dust explosion and electrostatic laboratories. There is also a laboratory for the evaluation of thermal mnaway reactions. Their clients are in more than 20 cormtries, and includes mamrfacturing corrtparties in the fine cherrricals/pharmacenticals, brrik organics, paints, resins/plastics, agrochemicals, soaps/detergents, oil/petrocherrricals, and a host of other fields. 

Many of the laboratory evaluations were run at the boiling point of the chemicals listed. This should not be considered the upper use temperature for Teflon resins In such environments, which can be considerably higher. 

After an overview of the scope of the chapter, each of these mechanisms was individually described in detail in Sections 10.2—10.8. Of course, each mechanism only has relevance depending on site-specific conditions as well as the specific type of geotextile resin and the formulation from which it was made. If a specific mechanism is involved, testing organizations have appropriate standards for such a laboratory evaluation. These standards were cited accordingly. The results of such testing are usually of a go—no go nature insofar as a final decision is concerned. 

Physical property testing involves the determination of a sample s response to mechanical deformation under a variety of testing regimes. Tests may determine the relationship of deformation to applied force, stress as a function of applied strain, or the energy required to fraeture a sample, or they may simply note a pass/fail result under specified conditions. Temperature, humidity, and other environmental factors may be varied to simulate end use conditions. Experiments may be performed on finished items for the purposes of quality control and product evaluation or on specimens speeially prepared under standardized conditions for the purposes of fundamental research or comparative evaluation of competing resins. Experiments performed in the laboratory infrequently duplicate the conditions found in service. Laboratory results should therefore be treated as comparative, useful for ranking specimens prepared from different resins under standard conditions but not necessarily indicative of service performance. 

The final step in the process of standardizing our columns was to try and maintain the high quality of columns from batch to batch of gel from the manufacturer. This was done by following the basic procedures outlined earlier for the initial column evaluation with two exceptions. First, we did not continue to use the valley-to-peak ratios or the peak separation parameters. We decided that the D20 values told us enough information. The second modification that we made was to address the issue of discontinuities in the gel pore sizes (18,19). To do this, we selected six different polyethylenes made via five different production processes. These samples are run every time we do an evaluation to look for breaks or discontinuities that might indicate the presence of a gel mismatch. Because the resins were made by several different processes, the presence of a discontinuity in several of these samples would be a strong indication of a problem. Table 21.5 shows the results for several column evaluations that have been performed on different batches of gel over a 10-year period. Table 21.5 shows how the columns made by Polymer Laboratories have improved continuously over this time period. Figure 21.2 shows an example of a discontinuity that was identified in one particular evaluation. These were not accepted and the manufacturer quickly fixed the problem. 

In one series of laboratory tests carried out to find the optimum wear resistance of heavy-duty epoxy resin flooring compositions, a number of different abrasion resistant materials were evaluated using BS 416, employing three different epoxy resin binders which themselves had significantly differing chemical compositions and mechanical properties. The results of this work, which was carried out under dry conditions, are given in Table 9.1. As can be seen from the table, the selection of the abrasion-resistant material and the resin matrix both influence the abrasion resistance of the system, although the abrasive material incorporated appears to play a more cmcial role. 

In 1940 most of the shellac imported into the United States came in through the docks of Brooklyn. It was, therefore, appropriate that W. H. Gardner had selected the Polytechnic as the site to establish a national testing laboratory a few years before. Research at the laboratory, called the Shellac Bureau, centered on evaluating the properties of this important natural resin. On assuming his position in Brooklyn, Mark was assigned to the Shellac Bureau. 

Using a laboratory technique previously developed to evaluate the performance of chemical foaming agents in XLPE foam, metallocene polyolefins are evaluated at various addition levels to branched LDPE to determine their effect on general foam quality (cell size, density, appearance). The laboratory method is discussed, and conclusions on acceptable levels of the metallocene resins are offered. 5 refs. 

Rather than extracting water with solvent, the water sample is poured through a column or filter containing an absorbent resin. The organics will preferentially adsorb to the resin, which is subsequently desorbed with solvent. This technique has been used for PAHs, pesticides, and PCBs and has been well characterized for drinking water. Laboratories should take proper steps to evaluate the efficiency of this technique for effluent samples or turbid samples and may refer to EPA method 3535A or to guideline documents from SPE suppliers (e.g., Supelco bulletin 910). 

The collector is molded from a mixture of carbon and phenolic resin which incorporates an in-situ formed titanium foil shield on the anode side to prevent corrosion. Small laboratory-sized collectors have accumulated over 12,000 hours of operational evaluation to date. Figure 7 shows large-sized molded collectors with 21/2 ft 2 active area. 

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