Inorganic fillers/organic additives

Several inorganic fillers/organic additives, such as silica, talc, kaolin, CaC03, titania, zeolites, cross-linked acrylic copolymers, spherical silicon beads, and so on, are employed in the plastics/coatings industry to attain the desired blocking performance. Some of these fillers are discussed elsewhere in this book in terms of their primary function only amorphous silica forms (natural and synthetic), used for antiblocking, will therefore be discussed in this chapter. 

In addition to the inorganic fillers, organic fillers such as high molecular weight styrenes, lignins and reclaimed rubber may be used. 

Principles and Characteristics Mass-spectral analysis methods may be either indirect or direct. Indirect mass-spectral analysis usually requires some pretreatment (normally extraction and separation) of the material, to separate the organic additives from the polymers and inorganic fillers. The mass spectrometer is then used as a detector. Direct mass-spectrometric methods have to compete with separation techniques such as GC, LC and SFC that are more commonly used for quantitative analysis of polymer additives. The principal advantage of direct mass-spectrometric examination of compounded polymers (or their extracts) is speed of analysis. However, quite often more information can be... 

The zeolites discussed so far have all relied on exotic organocations to function as SDAs. However, sometimes the inorganic cations can have a greater influence as demonstrated by the 12-MR zincosilicate, VPI-8 (65-68). The synthesis of VPI-8 still requires an organic additive but its role as template may be as a void filler. A recently determined model for the structure of VPI-8 viewed along the 001 direction is shown in Fig. 10 (69). Much like SSZ-31, the structure of VPI-8 involves ID channels running in parallel that are defined by odd-shaped 12-MR structures (6.2 x 5.97 x 5.88 A). An unusual feature of this structure is the pinwheel building unit that is composed of four 5-MR stmctures surrounded by another four 5-MR structures. 

Simple additions of organic or inorganic fillers and components... 

Flame-retardants are used as additives in the preparation of fire retardant paints. They are decomposed by heat to produce nonflammable components, which are able to blanket the flames. Both inorganic and organic types of flame-retardants are available in the market. The most widely used inorganic flame-retardants are aluminum trihydroxide, magnesium hydroxide, boric acid, and their derivatives. These substances have a flame-retardant action mainly because of their endothermic decomposition reaction and their dilution effect. The disadvantage of these solids is that they are effective in very high filler loads (normally above 60 percent). 

Combinations of inorganic and organic flame retardants are discussed hcrc. " Figure 13.6 shows than the addition of regular fillers, such as talc and CaCOs, to ammonium polyphosphate increased the fire resistance of PA-6. The function of filler in these combinations is to increase char yield and increase insulation properties of char. On the other hand, ammonium polyphosphate protects char Ifom oxidation and hinders diffusion of combustible gases to the flame. 

Simple tests can only indicate which polymer type the plastic contains. To identify materials more precisely, it is necessary to use instrumental analytical methods. Each technique provides specific information either about which polymers or which additives are present, so it is usually necessary to use several in combination. For example, gas chromatography-mass spectrometry (GC-MS) is a destructive technique which allows identification of the polymer, plasticizer and other organic components. X-Ray Fluorescence (XRF) spectroscopy is an effective, non-destructive surface technique for identifying inorganic fillers, pigments and metal components, but carmot be used to identify polymers. 

High viscosity filled hardener, containing inorganic fillers or organic thickeners, hardener, and sometimes some formaldehyde catcher and other additives. 

There are several fillers and inoiganic/organic additives used in flame retarded materials and these include antimony oxide, aluminum trihydrate, zinc borate, ammonium octamolybdate, and zinc stannate. The details related to the composition required and performance characteristics of inorganic additives can be found in specialized monograph. Some of these compounds are discussed below in relation to their effects on enhancement of performance of phosphate plasticizers. 

Fillers and other additives are used to make molded objects from phenolic resins to reduce shrinkage during cure, improve strength, and provide flow control. Representative materials added are mineral flour, wood flour, nutshell flour, pressed olive stones, lignite, and natural rubber. Crosslinked phenolics containing inorganic or organic fillers are schematically illustrated in Scheme 35. 

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