Coatings unfilled

The energy required to initiate an explosion and the maximum explosive pressure developed by a number of polyester—epoxy powder coatings has been studied in some detail (89). The variables studied included composition, level and type of pigmentation, particle size, and concentration in air. The lowest MEG for unfilled and unpigmented powders was 33—35 g/m. ... 

For resistance to acid conditions alone, traditional filled and unfilled bituminous solutions (which have economic advantages), chlorinated rubber and shellac have been used. Crosslinking coatings, e.g. amine-cured epoxy resins, often blended with coal-tar which develops resistance to oils and solvents, have obvious advantages on chemical plant. 

An example of the effectiveness of this equation is given by an aqueous HEUR gel made up of a polymer with Mn = 20 x 103 Daltons at a concentration of 30kgm-3 filled with a poly(styrene) latex with a particle diameter of 0.2 pm at q> = 0.2. The unfilled gel had a network modulus of 0.4 kPa, whilst the modulus of the filled gel was 0.7 kPa. Equation (2.68) predicts a value of 0.728 kPa. The poly(styrene) particles act as a non-interactive filler because the surface is strongly hydrophobic as it consists mainly of benzene rings and adsorbs a monolayer of HEUR via the hydrophobic groups, resulting in a poly(ethylene oxide) coating that does not interact with the HEUR network. This latter point was... 

Fig. 9. The effect of magnesium hydroxide filler type on the dynamic storage modulus G of polypropylene (PP) at 200 °C (strain amplitude 10%, filler level 60% by weight). Magnesium hydroxide fillers differed in origin particle size and treatment. Mean particle size (pm) type A ( ), 7.7 type B (+), 0.9 type C ( ), 4.0 type D ( ), 0.53 type E, stearate-coated version of type A, (X), 3.7 unfilled PP (O) [36]...

Fig. 8 Force normalized by radius as a function of surface separation. The forces were measured between muscovite mica surfaces across a 0.1 mM KBr solution containing 50 ppm chitosan-E045 oligomers. Filled and unfilled symbols represent forces measured on approach and on separation, respectively. The forces measured between mica surfaces coated with polymeric chitosan are represented by crosses. The arrows represent inward jumps due to the action of an attractive force...

These plastics, also known as pyrrones, are experimental materials prepared from aromatic dianhydrides and aromatic tetraamines. The polymer syntheses provide soluble prepolymers that are converted to the pyrrone structures by thermal or chemical dehydration. The precursors can be used to cast films or coatings, or can be molded under very high pressures into filled or unfilled forms. The pyrrones combine some of the best properties of the polybenzimidazoles and polyimides. The pyrrone films are exceptionally radiation resistant and retain their strength properties after 10,000 megarads of 1-MeV electrons. 

An investigation was carried out into the fire retardant behaviour of zinc hydroxystannate-coated fillers (alumina trihydrate and magnesium hydroxide) in PVC and EVA cable formulations. Measurements were made of the limiting oxygen index, peak rate of heat release and smoke parameter and the data for unfilled and filled formulations compared. X-ray photoelectron spectroscopy and diffuse reflectance infrared Fourier-transform spectroscopy were used to study the filler-coating interaction. 16 refs. 

The primer, defined in the first part of this paper as a cut-back of the same or a compatible, unfilled, oxidized asphalt dissolved in a high flash petroleum fraction, should be scrubbed into the concrete surface with a broom or stiff brush (roller or spray application is not recommended) and allowed to dry to permit the solvent to evaporate. This usually takes about 3 to 4 hours, at which time the odor of the solvent will have become faint. This leaves a black deposit of the asphalt in the pores and on the surface of the concrete. If the black color fades away, or becomes gray, the concrete is porous, and another coat of primer is necessary. Repeat until the surface remains black. 

Attempts to improve flexural strength by surface treatment of fillers have not, to date, been successful. A variety of silanes, titanates, and fatty acids and their derivatives have been used to coat magnesium hydroxide for use as a filler in polypropylene. " Almost all composites had inferior flexural properties. In the few cases where some improvement was seen, it was 10% more then the unfilled material. 

FIG. 9 The forces measured on approach between mica surfaces coated with PCMA (circles) and AM-CMA-10 (squares). The forces were recorded before (filled symbols) and after (unfilled symbols) the polyelectrolyte solutions were replaced with a solution containing no polyelectrolytes. 

Although FEP is available as a liquid dispersion, the commonly used material in liquid dispersion coatings are PFA and PVDF. Both materials are used in various ways such as filled or unfilled. T q)ical fillers for PFA are mica flakes. PVDF can be reinforced with fiberglass cloth or carbon fabric for additional permeation protection. T q)ical thicknesses achieved are up to 80 milli-inches (2 mm). PFA coatings are used with wire mesh reinforcment for additional protection from delamination. 

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