Acrylics bitumen

During the last decade many new roofing materials were introduced which are applied in the form of weldable membranes, liquid curable materials, self-adhesive products, and torchable materials. These materials are produced from numerous polymers such as, PVC, chlorinated polyethylene, chlorosulfonated polyethylene, EPDM, acrylics, bitumen, polymer-reinforced bitumen and several other materials. It is beyond the scope of this book to analyze compositional changes in these materials. We will provide a brief overview. 

Atmospheres polluted by oxidising agents, e.g. ozone, chlorine, peroxide, etc. whose great destructive power is in direct proportion to the temperature, are also encountered. Sulphuric acid, formed by sulphur dioxide pollution, will accelerate the breakdown of paint, particularly oil-based films. Paint media resistant both to acids, depending on concentration and temperature, and oxidation include those containing bitumen, acrylic resins, chlorinated or cyclised rubber, epoxy and polyurethane/coal tar combinations, phenolic resins and p.v.c. 

Acrylic resins, activated carbon, adipic acid, alfalfa, alga powder, alumina, aluminium, ammonium chloride, animal feed, anthracite, asbestos Barium chloride, barium sulfate, battery masses, bauxite, bentonite, bitumen, bone meal, borax, brass turnings... 

Previous investigators have drawn attention to the beneficial effect of lime when added in small quantities to asphaltic bitumen. The lime helps retard oxidative hardening (13) and reduces the tendency towards water-stripping (4,11,12). Most asphalts are slightly acidic because of the presence of phenolic or carboxylic substituents and would therefore react with basic oxides to form insoluble salts. For example, Fromm (10) has described the use of iron salts of naphthenic acids as adhesion promoters to improve the water resistance of asphalt concretes. This promising approach is now undergoing commercial trials. The literature also describes methods of chemically modifying asphalt with maleic anhydride or acrylic acid (14), sulfur trioxide (15), sulfur dioxide (16), acetyl sulfate (17-21), and sulfuric acid (20). (For a recent review of the interfacial phenomena in asphaltic compositions see Ref. 4.)... 

Cyclohexyl acetate [622-45-7] is very slightly miscible with water, but completely miscible with common organic solvents. Its solvency properties are comparable to those of amyl acetate. Cyclohexyl acetate dissolves oils, fats, resins, waxes, cellulose nitrate, cellulose tripropionate and acetobutyrate, alkyd resins, unsaturated and saturated polyester resins, phenolic resins and aminoplasts, poIy(vinyI chloride), vinyl chloride copolymers, poly(vinyl acetate), poly(vinyl ethers), epoxy resins, and acrylic resins, basic dyes, blown oils, crude rubber, metallic soaps, shellac, and bitumen. 

Chem. Descrip. Calcium sulfonate, mineral spirits Uses Wetting agent/dispersantfor inorg. and org. pigments in broad range of resins incl. alkyd, epoxy, chlorinated rubber, bitumen, polyurethane, acrylic, and polyester... 

Nowadays commercial mixtures of bitumens with uncured synthetic elastomers are produced, e.g. ethylene-propylene-diene terpolymers (EPDM), styrene-butadiene sequence copolymers (SBS), and ethylene-acrylic ester-acrylic acid terpolymers (AECM). Mixtures with some thermoplastics are also commercial products, e.g. polyethylene (PE), ethylene-propylene copolymers (EPM), alpha-olefinic copolymers, atactic polypropylene (aPP), and ethylene-vinyl acetate copolymers (EVA). 

The main thermoplastics used for the modification of the bitumen are the following ethylene vinyl acetate (EVA), polyvinyl chloride (PVC), polyethylene (PE), polypropylene (PP), polystyrene (PS), ethylene methyl acrylate (EMA) and ethylene butyl acrylate (EBA). 

PVC and PE have played a major role in the shift of early roof waterproofing technology and materials. After the introduction of elastomeric and other thermoplastic materials, flexible membranes of polychloroprene (Neoprene) rubber, butyl rubber and Hypalon were used. Later on, liquid PU, solvent-based liquid acrylate and liquid EPDM systems, in addition to new materials like SBS modified bitumens, were also used in the management of roofing. All fall into the single-ply family of roofing, which offers a much cleaner, safer, energy-efficient and cost-effective alternative to built-up roofs. 

Sand. In compact sandy soils, bitumens, which are not water-soluble, are the most effective dust suppressant. Water-soluble suppressants such as salts, Hgnons, and acrylics will leach from the upper road smface. However, in loose, medium, and fine sands, bearing capacity will not be adequate for the bitumen to maintain a new surface. 

A complete range of such items would include bitumen/rubber blends, acrylic elastomer, drying oil-based sealants. 

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