Feldspar filler

Unispar. [Unimin Specially Minerals] Feldspar fillers and flatting agents for traffo paint, interior/exterior atdiitec-turai coatings, protective, maintenance and marine coatii, mastics and adhesives. 

Table F. 1 Major Applications and Advantages of Feldspar Filler...

Unispar sicronizsd feldspar fillers are processed fros a naturally white, chemically inert feldspar with exceptionally low soluble salts. The result is a superior, reinforclnp mineral filler which is particularly effective in strengthening and enhancing a variety of industrial paint systems ranging from maintenance coatings to traffic paints. An economical ttorkhorse, Unlspar offers formulators many critical performance properties to help achieve a balance between performance and cost. 

It is possible to cut costs by incorporating cheap fillers such as calcium carbonate, talc, kaolin, feldspar, wollastonite, silica. .. or by using recyclates and, to a certain extent, by foaming, which leads to an increase of the volume for the same weight of resin and other expansive ingredients. 

Feldspars are the most abundant minerals in the earth s crust, accounting for about 60% of all igneous rocks. They are derivatives of silica in which about one-half or one-quarter of the silicon atoms have been replaced by aluminum. Feldspar is used in the manufacture of certain types of glass and pottery. Some feldspar crystals, such as moonstone (white perthilte), Amazon stone (green microcline), and multicolored labradorite, are used as gem stones and in architectural decorations. Some are used as a coating and filler in the production of paper. 

Kaolin clays are naturally occuring sedimentary deposits composed largely of kaolinite mineral. Typical impurities in these deposits are iron oxides, titanifer-ous minerals, silica, feldspar, mica, sulfides and organic matter. The majority of kaolin clay produced in the world is used in the paper industry as coating and filler materials. This mineral also makes an excellent filler, carrier, opacifier and diluent in a variety of industrial products such as paints, plastics, cement, rubber, pharmaceuticals, etc. 

A clay mass is a mixture of clay and additives for a specific ceramic (processing) technique. The clay provides the plastic properties. Possible additives are a flux and a filler. Some examples of fluxes are potassium feldspar, bone meal, volcanic ashes and ground glass, all of which serve to affect the density and decrease the melting range. Fillers reduce the shrinkage as well as the sticky character of the clay. 

Figure 4.1 Diffraction patterns of usual sample holders (0.5° div. slit). For thin samples, or with a too wide divergence slit, these patterns may be superimposed on the sample pattern. For a plastie framed background free Si single crystal holder a plastic hump appears in the lower angle area (for 1° div. slit this starts already at 18 ), The sharp reflections in 2 originate from the inorganic filler (feldspar ). Normal white Perspex resembles the given plastic curve (4). A blue Perspex of unknown origin was found to be almost free of background (3).

Felex 100. [Feldspar] Feldspar, 325 mesh filler exiento. 

Kaolinite is one of the most important clays in industry. It is used as a filler in paper and is also extensively used in the rubber and ceramic indus- tries. The clay is found as a secondary mineral formed by the weathering or hydrothermal alteration of aluminum silicates, particularly feldspars. Kaolinite occurs naturally in almost every country of the world. 

G-FilL [Feldspar] Feldspathic sand filler extender. 

Other inorganic antiblocking fillers such as calcium carbonate, alumina-silicate ceramic spheres, zeolite, kaolin day, feldspar, and mica have also been used as antiblocks. In PE film, caldum carbonate can provide the low blocking force of talc and DE, but only when loaded at 2-3 times their concentration (or higher), reducing darity of the film, and increasing its density [12-1, 12-22, 12-30]. 

Chem. Descrip. Sodium feldspar CAS 1344-00-9 EINECS/ELINCS 215-684-8 Uses Filler, flatting agent for traffic paints, interior/exterior architectural coatings, protective, maintenance and marine coatings, mastics and adhesives... 

Good mica, talc, magnesium dihydrate, other silicate fillers (feldspar, nepheline syenite, etc.), inorganic oxides... 

Nepheline ne-fo- len [F nepheline, fr. Gk nephele cloud] (ca. 1814) n. A naturally occurring mineral composed mainly of feldspar and nephelite. As a filler in PVC compounds, it has the unique property of contributing almost no opacity, so that it can be used in nearly transparent compounds. It is also used as a filler in epoxy and polyester resins. 

Besides mechanical properties, fillers change the optical and electrical properties, chemical and weathering resistance, flammability and density of polymers. In particular, most fillers destroy optical translucency, unless their refractive index (see Table 4.4) is the same as that of the polymer. Close agreement between the fibre and the polymer refractive index is required for translucency. Feldspar has a refractive index very similar to that of several polymers and so filled, translucent products can be obtained, but it is abrasive to processing equipment. 

A number of other less widely used mineral fillers are available from several suppliers, including some large mining companies. Sibelco is marketing Sibelite (pure silica) as well as Minex nepheline syenite fillers for plastics, and Siokal feldspars that contain muscovite mica. 

These fillers are easily wet and dispersed enable transparency and translucence in most polymers and exhibit chemical, weather, and abrasion resistance. They are snitable for food contact. Feldspar s transparency and matched index of refraction allow its nse with transparent plastics to produce reasonably transparent componnds. 

Feldspar is not considered a general-pnrpose filler, bnt it does have large-volume sales as well as special uses in many prodncts. Major applications and advantages of its use are shown in Table F.l. 

The combination of acid resistance and abrasion resistance of feldspar makes it a preferred filler in applications snch as pipe that is intended to transport abrasive and acidic slurries. 

Nepheline syenite is also a filler derived from igneous rock. It is used in many of the same polymers and for the same reasons that feldspar is used. Nepheline syenite is generally available in finer grades that are more suitable to thermoplastics and extrusion processing. The filler provides abrasion resistance in the finished product as well as reduced abrasive wear on extrusion dies and equipment. 

Mineral fillers include aluminum trihydrate, calcium carbonate, calcium sulfate, feldspar, Kaolin, mica, silica, talc, titanium dioxide, and wollastonite. These improve properties such as flame resistance, impact strength, and color. Table F.3 shows the major resin markets for selected mineral fdlers/reinforcements. 

Feldspar, nepheline syenite Speciality filler easily wetted and dispersed gives transparency/translucency resistant to chemicals and weathering... 

Fillers. Fillers are used in compounds to increase viscosity, increase solids, and to lower cost. Most fillers used in latex do not exhibit the reinforcing effect that is characteristic of their use in dry-type polychloroprene. Water-washed whiting (calcium carbonate) can be added directly to the latex. Most clays are acids and must be neutralized and slurred before adding to the latex. When used at levels ranging from 10- to 20-phr, fine clays such as DIXIE Clay (R. T. Vanderbilt Co.) can add some degree of reinforcement. Hard clays have much smaller particle size than soft clays. Feldspar can be added directly to the latex but will tend to settle quickly. Hydrated alumina is used primarily to improve flame retardancy and improve water resistance. Large-particle-size hydrated alumina can be added directly to the latex. 

The fillers described previously form the bulk of materials used in rubber applications. The list is by no means exhaustive but those that are not covered are more specialised in use. Other fillers known to be used in rubber include calcium sulphate, cork, dolomites, feldspar, graphite, lead, lithopone, magnesium carbonate, molybdenum disulphide, rubber crumbs, textile fibres (flocks), wollastonite, wood flour, zinc oxide and many others. 

---