Emulsified cationic asphalt

Table 3.15 Types and requirements for cationic emulsified asphalt ...

Source Reprinted from ASTM D 2397, Standard specification fi>r cationic emulsified asphalt. West Conshohocken, Pennsylvania, USiASTM International, 2012. With permission ( ASTM International). 

AASHTO M 208. 2009. Cationic emulsified asphalt. Washington, DC American Association of State Highway and Transportation Officials. 

Only those grades of emulsified asphalt in general use have been indicated herein. It is possible that under certain variation of aggregates and/or climatic conditions, additional selections might be appropriate. Where the use of emulsified asphalt for applications other than those listed in the table are contemplated, the emulsion supplier should be consulted k Unless otherwise noted C Cationic D2397. 

Electrophoresis of the bitumen droplets to the aggregate surface depends both on the charge on the asphalt droplets and on the aggregate surface, as well as the size of the bitumen droplets - small particles mean faster-setting emulsions. The rise in pH resulting from the contact of emulsion with the aggregate surface or filler in the mixture, can result in a deprotonation of the cationic emulsifiers and consequent destabilization of the emulsion. 

Asphalt emulsions are used in road paving for the production of a smooth, water-repellant surface. First, an asphalt O/W emulsion is formulated, which has sufficiently low viscosity to be easy to handle and apply, and which has sufficient stability to survive transportation, brief periods of storage, and the application process itself. The emulsion needs to be able to shear thin during application, and then break quickly when it contacts the aggregate. The asphalt emulsions are usually 40-70% bitumen and stabilized either by natural naphthenic surfactants released by treatment with alkali (for a somewhat similar situation involving bitumen processing see also [64]), or else by the addition of anionic or cationic surfactant [106]. Emulsified asphalt can be applied to gravel or rock even when wet [1,20,105,106]. 

These compounds are widely employed as fabric and textile softeners, for the manufacture of organo-mod-ified clay for drilling mud, as bactericides and as cationic emulsifiers for asphalt. 

Typical cationic emulsifier formulations are based on tallow amine and tallow diamine. The type of emulsifier used depends on the specific asphalt, the aggregate and the intended application most asphalt emulsions are used in road maintenance applications. The... 

Chem. Descrip. Amine-based emulsifer Ionic Nature Cationic Uses Asphalt emulsifier Properties Liq./solid 50-100% cone. 

Emulsifiers and Stabilizers Both anionic (INDULIN C) and cationic (INDULIN W-l) derivatives of non-sulfonated kraft lignin are commonly used as stabilizers for making asphalt, wax, or oil-in-water emulsions. 

A typical formulation for a cationic asphalt emulsion calls for 0.5% tallow amine emulsifier and 70% asphalt, the rest consisting of water and water-soluble ingredients. How much asphalt can be emulsified per pound of emulsifier ... 

Redicote. [Akzo Akzo Chem. BV] Cationic asphalt emulsifiers. 

Nissan Amine. [Nippon Oils Fats] Amines interm ate for cationic surfactants anticorrosive agent germicide, wetting agent mdd release agent softener, emulsifier, dispersant intermediate used in textiles, water treatment concrete, asphalt agriculture, ceramics. 

For application purposes it is often found that asphalt emulsions stabilized by cationic surfactants function better than such emulsions stabilized by anio- nic surfactants. One main reason is that the interaction between the emulsion droplet and the road material differs depending on the emulsifier used (37). When the asphalt emulsion is spread on the road surface it should rapidly break and form a homogeneous layer. The stones on the road surface are often negatively eharged and there will be an electrostatic attraction between cationic emulsion droplets and the stones. This attraction facilitates the attachment and spreading of the emulsion. On the other hand, when the emulsion droplet is negatively eharged there will be an electrostatic repulsion between the stones and the emulsion droplets. 

Uses Emulsifier, corrosion inhibitor, softener, antistat, wetting agent, flocculant, lubricant for textiles, asphalt, car wax emulsions, cleaners, paint mfg., agric. applies., syn. coolants dispersant for clay and pigments in solv. systems tar emulsion breaker Properties Brn. liq. amine odor sol. in min. oil and spirits, aromatic solv., perchloroethylene water-disp. dens. 0.94 g/ml f.p. 5 C cationic 85% act. 

Chem. Descrip. Stearyl amine CAS 124-30-1 EINECS/ELINCS 204-695-3 Uses Intermediate for cationic surfactants corrosion inhibitor, germicide, wetting agent, mold release agent, softener, emulsifier, dispersant used in textiies, water treatment, concrete, asphalt, ceramics, paints, metals, rubber, plastics anticaking agent in agric. 

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