Resin fines

Property Granular resin Fine powder ASTM method... 

Fine Powder Resins. Fine powder PTFE resins are extremely sensitive to shear. They must be handled gendy to avoid shear, which prevents processing. However, fine powder is suitable for the manufacture of tubing and wire insulation for which compression molding is not suitable. A paste-extmsion process may be appHed to the fabrication of tubes with diameters from fractions of a millimeter to about a meter, walls from thicknesses of 100—400 )J.m, thin rods with up to 50-mm diameters, and cable sheathing. Calendering unsintered extmded soHd rods produces thread-sealant tape and gaskets. 

Most types of ion-exchange resin suffer some breakdown and volume loss over time because of attrition, excessive heat, or other factors. Water softeners should be inspected annually, and a double backwash procedure should be provided. This generally lifts the broken resin ( fines ) to the top of the bed, where it can be removed and replaced to restore capacity. Allow for 5 to 10% resin operating capacity loss per year because of physical breakdown. At many sites the resin is unfortunately not inspected regularly but merely replaced when a serious decline in operating capacity is noticed. Here a resin life expectancy of, say, 6 to 8 years probably is the norm. 

Property Granular Resin Fine Powder ASTM Meth... 

Backwashing Backwashing the resin removes suspended solids and resin fines that may have collected in the vessel. Typical flow rates for backwashing range from about 4 to 8 gpm/ft2 for a minimum of 10 minutes or until the backwash water runs clear. The target is to expand the bed by 50% for adequate backwash. Backwash water is usually sent to drain. 

Backwashing is necessary to keep the bed in a hydraulically classified condition, to minimize pressure drop, and to remove resin fines and suspended solids that have been filtered out of the influent water. Normal practice is to backwash at the end of each run for about 15 min, so as to obtain about 50 to 75 percent bed expansion. The flow rate required to achieve this expansion is obtained from the manufacturers data. As noted in the statement of the example, an appropriate flow rate in this case is 6.4gal/(min)(ft2). The total backwash rate is thus [6.4gal/(min)(ft2)](14ft2) = 90 gal/min. The total water requirement, then, is (90 gal/min)(15 min) = 1350 gal (5.11 m3). 

Fine-cut granular resins resnlting from size redaction of the snspension polymer have a typical average particle size 20 pm to 40 pm. The small particle size of hne-cnt PTFE imparts the highest possible mechanical properties to articles made from grannlar resins. Fine-cnt resins (powders) have poor flow and low apparent density... 

Microfilters use membranes with pores in the 0.1-1 pm range. They can filter out particles of dust, activated carbon, and ion exchange resin fines, and most microorganisms. Microfilters require low differential pressures (5-20 psi) and are available both as normal flow ( dead end ) and crossflow configurations. In pharmaceutical water purification systems, they are often used as disposable cartridge filters after activated carbon filters, softeners, and ion exchange beds. 

To remove small broken fragments of ion exchange resin or resin fines arising through normal anticipated resin degradation, but only fragments small enough to be carried out with the upward flow will be removed. 

A relatively new generation of filled polyols was obtained by the reaction of an epoxy resin with an epoxy hardener in situ, in liquid polyether media. Cured epoxy resins, finely dispersed in the liquid polyether (with around 20% solid content), are obtained. 

CAS 112-47 EINECS/ELINCS 203-975-2 Uses Pharmaceuticals personal care prods. flavors fragrances polyesters acrylates epo) diluents plastics coatings inks photographic materials textiles leather lubricants polyurethanes agile. solvents modifiers in all d resins fine chems. plasticizers Manuf./Distrib. Aldrich Inti Chem. Group Jarchem Ind. Penta Mfg. ... 

Resin fines] thermal or physical shock/freeze/thaw. 

Dechlorinated and softened water flows to the RO skid through a 5.0-nm (nominal pore size) cartridge filter. The cartridge filter removes resin fines, particles and complexed colloids necessary to protect the RO membranes from particulate fouling. The RO membranes are thin-film composite (TFC) polyamide RO membranes (20 cm diameter X 100 cm long spiral wound elements) with rejection 99%. 

Media or resin fines in the cartridge filter indicates that a vessel distributor/lateral has failed... 

The rate of depolymerizing polyacetal to formaldehyde is the subject of much research, because the rate of depolymerizing is a critical factor in MIM costs, and there is not that much proven information on it. Removal of binder is determined by various factors, namely, binder removal temperature, about 120°C (248°F) catalyst linear or random degradation of polyacetal resin fineness of powder mold part shape and size and catalytic debinding furnace. The catalytic furnace developed for debinding... 

The mixed bed demineraliser in service can be supplemented by intermittent use of the cation bed demineraliser for additional purification in the event of fuel defects. In this case, the cation resin removes mostly lithium and caesium isotopes. The cation bed demineraliser has sufficient cqiacity to maintain the cesium-136 concentration at acceptable levels with the assumed level of Design Basis fuel defects. Each mixed bed and the cation bed demineraliser is sized to accept the maximum purification flow. Filters are provided downstream of the demineralisers to collect particulates and resin fines. 

After deionisation, the water passes through an after-filter, where radioactive particulates and resin fines are removed. The processed water then enters one of the monitor tanks. When one of the monitor tanks is full, the system automatically realigns to route the processed water to another monitor tank. 

Figure 7. Thermogravimetric Analysis of Tospearl 120 and Organic Resin Fine particles.

I he chemical industry manufactures a very large number of products for different uses. In industrial parlance, the products are often classified under different categories such as polymers and resins, fine chemicals, flavors and fragrances, and pharmaceutical intermediates. Some of these such as plastics are produced in millions of tons, while some others less than a few tons per year. As we will see, homogeneous catalysis plays an important role at both these extremes. 

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