Fillers wettability

Precipitated calcium carbonates are generally surface-treated to render them hydrophobic and to improve their dispensability in hydrophobic systems. Conventional surface treatment of CaC03 is with fatty acids. However, the use of different types of acids yields subtle differences in filler wettability and polymer compatibility. 

An unaccelerated, low styrene content resin offering good filler wettability, specifically designed for the hot casting of polymer marble slabs. 

An unaccelerated orthophthalic resin offering good filler wettability for the cold casting of polymer marble... 

An amine accelerated orthophthalic with good filler wettability for putties. 

An unaccelerated, orthophthalic of excellent flexibility, offering excellent glass and mineral filler wettability in the manufacture of SMC BMC compounds. 

The main purpose of pesticide formulation is to manufacture a product that has optimum biological efficiency, is convenient to use, and minimizes environmental impacts. The active ingredients are mixed with solvents, adjuvants (boosters), and fillers as necessary to achieve the desired formulation. The types of formulations include wettable powders, soluble concentrates, emulsion concentrates, oil-in-water emulsions, suspension concentrates, suspoemulsions, water-dispersible granules, dry granules, and controlled release, in which the active ingredient is released into the environment from a polymeric carrier, binder, absorbent, or encapsulant at a slow and effective rate. The formulation steps may generate air emissions, liquid effluents, and solid wastes. 

In addition to the amount of filler content, the shape, size and size distribution, surface wettability, interface bonding, and compatibility with the matrix resin of the filler can all influence electrical conductivity, mechanical properties, and other performance characteristics of the composite plates. As mentioned previously, to achieve higher electrical conductivity, the conductive graphite or carbon fillers must form an interconnected or percolated network in the dielectrical matrix like that in GrafTech plates. The interface bonding and compatibility between... 

Keywords aggregation, interfacial interaction, reversible work of adhesion, wettability, matrix-filler interaction, surface treatment, interphase, surfactant, coupling agent, elastomer interlayer... 

Surface modification of the fillers and curing agents in order to increase their wettability and interaction with the polymers... 

Adsorption Properties. Due to their large specific surface areas, carbon blacks have a remarkable adsorption capacity for water, solvents, binders, and polymers, depending on their surface chemistry. Adsorption capacity increases with a higher specific surface area and porosity. Chemical and physical adsorption not only determine wettability and dispersibility to a great extent, but are also most important factors in the use of carbon blacks as fillers in rubber as well as in their use as pigments. Carbon blacks with high specific surface areas can adsorb up to 20 wt% of water when exposed to humid air. In some cases, the adsorption of stabilizers or accelerators can pose a problem in polymer systems. 

The surface of PDMS is hydrophobic which results in poor wettability with aqueous solvents and promotes non-specific protein adsorption. It is also relatively inert to chemical modification [25]. The liquid silicon rubber chosen for fabrication of the reaction plate contained pyrogenic silicic acid as a filler. Aside from its effect on elastomer properties the silicic acid can be expected to provide additional silanol... 

The characterization of surface activity of fillers is obtained by use of several analytical techniques [1]. Examples of them are inverse gas chromatography [1, 2], the adsorption of a low molecular weight analog of elastomers [3], the adsorption of elastomer chains fi om dilute solutions [4], the wettability, viscosity of PDMS fluids in the boundary layer at the surface of solids [5], the determination of the specific surface area, and the analysis of surface groups [1]. It should, however, be mentioned that the results obtained by these methods do not provide direct information on the elastomer behavior at the interface, due to the use of small probe molecules or the presence of a solvent in the systems studied. 

It has been well known that weak interfaces between the inorganic fillers and the organic matrix reduce the mechanical strength of bone cement [38,40,44,45]. The interfacial adhesion strength can be enhanced by plasma treatment, which is generally due to the improved wettability and possibly to the chemical bonds between the filler and the resin [46,47]. Especially in acrylic bone cement, chemical bonds may have an important role in improving the mechanical strength by the plasma treatment. 

The Part 14 of ISO 787 gives details of the method. A sample is prepared in boiling water. If the filler is hydrophobic some methanol is added to increase its wettability. The extract is filtered, cooled to room temperature, and measured in a conductivity cell. The result is expressed as resistivity. 

Applications. The following uses of contact angle were reported in the literature surface energy of different sizes for fibers, correlation between contact angle of fiber and interlaminar shear strength of composite, effect of surface treatment of fillers for paints, the matrix-filler adhesion parameter for PS filled with CaCO, dispersion stability of PEO-modified kaolin particles, determination of contact angle of carbon fibers and its dependence on treatment, wettability of fiber sur-... 

Chemical composition, particle size, particle shape, specific gravity, surface area, refractive index, brightness, absorptivity, and wettability are the most important criteria used in selecting a filler for the paper industry. For further reading, a recent monograph on the use of fillers in paper industry is an excellent source of practical information. ... 

Several properties of the filler are important to the compounder (279). Properties that are frequently reported by fumed silica manufacturers include the acidity of the filler, nitrogen adsorption, oil absorption, and particle size distribution (280,281). The adsorption techniques provide a measure of the surface area of the filler, whereas oil absorption is an indication of the structure of the filler (282). Measurement of the silanol concentration is critical, and some techniques that are commonly used in the industry to estimate this parameter are the methyl red absorption and methanol wettability (273,274,277) tests. Other techniques include various spectroscopies, such as diffuse reflectance infrared spectroscopy (drift), inverse gas chromatography (igc), photoacoustic ir, nmr, Raman, and surface forces apparatus (277,283—290). 

Resins based on dicyclopentadiene (DCPD) offer better wettability of fillers and better prevention of print-through than conventional unsaturated polyesters, making them particularly suitable for appearance parts in transportation and marine applications. Polyesters based on DCPD require special chemical competence on the part of the fabricator, but... 

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