TOFA 180 (Tall Oil Fatty Acids 180) is a fatty-acid feedstock used in bitumen/asphalt applications for two core functions: it is an intermediate in the production of anti-stripping additives that improve adhesion between bitumen and mineral aggregate, and of emulsifiers that keep droplets stable in bitumen emulsions. Being an economical feedstock with a high tolerance for rosin and unsaponifiables makes it a preferred choice in both hot- and cold-mix road technologies.
What does TOFA 180 do in asphalt?
The durability of an asphalt pavement depends largely on how well the bitumen binder adheres to the aggregate surface. Water can penetrate this interface and separate the bitumen from the aggregate — a phenomenon called stripping, which leads to early pavement failure. TOFA 180 serves as a fatty-acid source for reaction with amines to produce amidoamine/imidazoline-type surface-active additives; these additives function both as anti-stripping agents and as emulsifiers.
The long hydrocarbon tail of the fatty acid has affinity for bitumen, while the polar head group of the amine derivative anchors to the mineral aggregate surface (particularly to silica-rich, acidic aggregates). This forms a water-repellent, durable bond at the bitumen-aggregate interface and reduces moisture-induced stripping.
The emulsifier role in bitumen emulsions
Bitumen emulsions are systems in which bitumen is dispersed as fine droplets in water and can be applied near ambient temperature; they are used in cold mixes, surface dressings (chip seals), primers and tack coats. Surfactants derived from TOFA 180 form a film on the surface of these droplets, delaying their coalescence and keeping the emulsion stable throughout its shelf life. Whether the emulsion is anionic or cationic depends on which chemistry (alkali soap or amine/amidoamine) is used to derivatize the TOFA.
Why TOFA 180?
Asphalt additives do not require color or high purity; what matters is the appropriate reactivity of the fatty-acid chain and the cost. TOFA 180's tolerance of max. 3% rosin and max. 6% unsaponifiables delivers sufficient performance for this application at an economical price. The resin acids can also add adhesion and compatibility with bitumen.
BİO BAZLI ÜRÜNLERTall Oil Fatty Acids 180 (TOFA)KORKİMYA supplies TOFA 180 in bulk (ISO tank, 20-24 MT net) to manufacturers of asphalt anti-stripping agents and bitumen emulsifiers.Within the same bio-based raw-material family, tall-oil-pitch-based products (Ecophalt) can play a complementary role as a bitumen modifier and fluxing agent; they are evaluated alongside TOFA 180 according to formulation goals.
Safe handling and storage
- Store in closed containers in a cool, dry, well-ventilated area; keep away from oxidizers.
- Can be stored in bulk in carbon-steel or stainless-steel tanks.
- Shelf life is 12 months and can be extended to 24 months following a quality-control test.
- Prolonged air exposure can darken the color; keep containers tightly closed.
Is TOFA 180 added directly to asphalt?
Usually not. TOFA 180 is mostly first reacted with amines to form an amidoamine/imidazoline-type surfactant; this additive is then added to the asphalt/bitumen system as an anti-stripping agent or emulsifier.
How does an anti-stripping additive prevent stripping?
The additive's polar head group anchors to the mineral aggregate surface while the fatty-acid tail has affinity for bitumen. This forms a water-repellent, durable bond at the bitumen-aggregate interface and reduces the separation of bitumen from aggregate by moisture.
Is TOFA 180 used in hot mix or cold mix?
Both. In hot mix it is used as an anti-stripping additive, and in cold mixes and bitumen emulsions it is used as an emulsifier feedstock.
Does TOFA 180 make an anionic or cationic emulsion?
It depends on the derivatization. Saponified with alkali it gives anionic emulsifiers, while conversion with amines to amidoamine/imidazoline gives cationic ones; the choice is made according to aggregate type in road applications.