Coated polymer fillers

One way of improving the adhesion between polymer and filler is to improve the level of wetting of the filler by the polymer. One approach, which has been used for many years, is to coat the filler with an additive that may be considered to have two active parts. One part is compatible with the filler, the other with the polymer. Probably the best known example is the coating of calcium carbonate with stearic acid. Such coated or activated whitings have been used particularly with hydrocarbon rubbers. It is generally believed that the polar end attaches itself to the filler particle whilst the aliphatic hydrocarbon end is compatible with the rubbery matrix. In a similar manner clays have been treated with amines. 

Aid in the uniform dispersion of additives. Make powdered solids (e.g. particulate fillers with high energy and hydrophilic surface) more compatible with polymers by coating their surfaces with an adsorbed layer of surfactant in the form of a dispersant. Surface coating reduces the surface energy of fillers, reduces polymer/filler interaction and assists dispersion. Filler coatings increase compound cost. Fatty acids, metal soaps, waxes and fatty alcohols are used as dispersants commonly in concentrations from 2 to 5 wt %. 

Many coating polymers contain additives and compounding ingredients to improve the physical durability, flexibility and performance. Rubber coatings in particular usually include carbon black and inorganic fillers to improve physical properties or reduce costs. 

Qualitative analysis of common plasticisers is complicated by the fact that there may be other fillers and additives in the coating polymer. It is important to dissolve out the plasticiser in a reflux apparatus with suitable solvent such as ether, methanol or carbon tetrachloride. 

Polymers and biopolymers can not only be active substances but also preparation bases (e.g. ointment and suppository bases), stabilizing additives in emulsions and suspensions, fillers, binders, disintegrants, lubricants, and gli-dants in tablet preparation. Coating polymers lead us to a major field of modern pharmaceutical technology, which is controlling the release or dissolution of active substances. 

Masonry coating inaterials, which are the mixture of organic polymer, filler and fine aggregates, often applied some 0.3 to 15mm thick by sprayingor rolling on the various types of external surface such as concrete, cement mortar, asbestos cement sheets and other boards, are objects in this investigation. 

Virtually all polymers deteriorate under exposure to outdoor weathering and solar radiation, but at greatly varying rates. Polymers In solar equipment must maintain optical, mechanical, and chemical Integrity despite prolonged exposure to solar ultraviolet radiation. For most outdoor applications of polymers, solar radiation exposure Is Incidental, but for many solar applications, exposure to solar radiation Is deliberately maximized In the equipment design. Transparency Is essential for many of the potentially most cost-effective applications, and conventional approaches to ultraviolet protection such as opaque coatings and fillers are unacceptable. 

Disperse oxides unmodified or modified by organics (OC) or OSC are used as fillers, adsorbents, or additives [1-11]. OSCs are used as promoters of adhesion, inhibitors of corrosion, for the stabilization of monodisperse oxides and the formation of the nanoscaled particles. Oxide modification by alcohols or other OC is of interest for synthesis of polymer fillers, as such modification leads to plasticization and reinforcement of the filled coating, but in this case a question arises about hydrolyz-ability of the =M—O—C bonds between oxide surface and alkoxy groups, as those are less stable than =M—O— M= formed, for example, upon the silica modification by silanes or siloxanes. The high dispersity, high specific surface area, and high adsorption ability of fumed oxides have an influence on their efficiency as fillers of polymer systems. 

Conductive filler Plated resin powder (8 tm) Nickel and metal coated resin particles Gold-coated polymer... 

CAS 1327-36-2 EINECS/ELINCS 215-475-1 Uses Reinforcing agent, extender for EPDM, SBR, nitrile, most other polymers filler in solvent and water-based coatings and inks Features Offers superior disp. 

CAS 2634-33-5 EINECS/ELINCS 220-120-9 Uses Preseivative, bactericide, fungicide, yeast inhibitor for aq. coatings, polymer disps., filler suspensions, slurries, sol ns. and disps. of adhesives and thickeners, concrete additives, other aq. formulations Features Broad spectrum Preventol Cl 8-100 [Bayer AG Sea-Land]... 

Schaefer et al. (19) studied the interphase microstructure of ternary polymer composites consisting of polypropylene, ethylene-propylene-diene-terpolymer (EPDM), and different types of inorganic fillers (e.g., kaolin clay and barium sulfate). They used extraction and dynamic mechanical methods to relate the thickness of absorbed polymer coatings on filler particles to mechanical properties. The extraction of composite samples with xylene solvent for prolonged periods of time indicated that the bound polymer around filler particles increased from 3 to 12 nm thick between kaolin to barium sulfate filler types. Solid-state Nuclear Magnetic Resonance (NMR) analyses of the bound polymer layers indicated that EPDM was the main constituent adsorbed to the filler particles. Without doubt, the existence of an interphase microstructure was shown to exist and have a rather sizable thickness. They proceeded to use this interphase model to fit a modified van der Poel equation to compute the storage modulus G (T) and loss modulus G"(T) properties. 

Yim and co-workers developed a microwave frequency model for ACF-based flip chip joints based on microwave network analysis and S-parameter measurements. By using this model, high frequency behavior of ACF flip chip interconnections with two filler particles, Ni and Au-coated polymer particles, was simulated. It was predicted that Au-coated polymer-particle-fllled ACF flip chip interconnections exhibited comparable transfer and loss characteristics to solder bumped flip chips up to about 13 GHz and thus they can be used for up to 13 GHz, but Ni-filled ACF joints can only be used for up to 8 GHz because the Ni particle has a higher inductance compared to the Au-coated particle. Polymeric resins with a low dielectric constant and conductive particles with low inductance are desirable for high resonance frequency applications (24). 

---