| 摘要 |
A structural element is made by admixing a finely divided aggregate with 3-30 wt. per cent, based on aggregate, of a bituminous binder; compacting under pressure; and curing at 250-550 DEG F. (120-290 DEG C.) for 2-80 hrs.; the aggregate is contacted with a hydrophobic amine. The amine may be a C8- 24 cmpd., e.g. octadecylamine and may be added to the aggregate when curing e.g. as a vapour, or before the bitumen is added; or the amine may be added to the bitumen before mixing or to the mix; or the amine may be applied to the cured material in water emulsion. The composition may contain 0.005.2% wt. amine. The bitumen may have ASTM softening pt of from below 75 DEG F. (23.9 DEG C.) to 235 DEG F. (113 DEG C.). The asphalt may be cut-back in a volatile solvent, e.g. a hydrocarbon of halohydrocarbon, e.g. toluene, benzene, xylene, mineral spirits, naphtha, Stoddard solvent, kerozene, CCl4, or CH2 Cl2. The penetration of the asphalt or cut-back may be 18-335 mm./10 (77 DEG F.). The bitumen may be natural, artificial or chemically modified, a large number being exemplified. 1-10 wt. per cent. of natural or synthetic thermoplastic or thermosetting substances e.g. rubbers, resins, and elastomers, may be added to the bitumen. A reagent liquid, e.g. CCl4, may be added to the asphalt as a solvent, the modifying reaction occurring before, during or after compacting or curing. The aggregate may be any dry inorganic or organic comminuted solid matter, e.g. earth, soil, clay soils of particle diameter < 5 m , iron ore fines, cinder, expanded slag or clay, rock wool, steel wool, abrasives, cellulose fibres, sawdust, cane fibres, bagesse, hemp, jute, coke, iron ore, diatomaceous earths, silt, coal, asbestos, glass fibres, wood chips, quartz, carbonate rocks, volcanic ash, bamboo, chlorite, talc, mica, illite, attapulgite, montmorillonite, bentonite, allophanes, or kaolinite. |
