Polyacrylonitrile Fiber
(PANF)
Product introduction
Polyacrylonitrile fiber (PANF) is a new reinforced fiber applied in asphalt or cement concrete to strengthen and prevent cracking. It is a synthetic fiber made of polyacrylonitrile resin through particular processing. The effect of mixing into cement concrete is similar to that of concrete with polypropylene fiber, and the role of mixing into asphalt concrete is roughly identical to that of concrete with polyester fiber.
Adsorption of PANF
The fiber diameter is relatively small and has a large specific surface area which, provided by each gram, can reach tens of thousands of square meters. Therefore, the fibers are dispersed in the bitumen, and their vast surface area becomes the wetting interface. In the interface layer, there will be physical and chemical interactions between the asphalt and the fiber so that the asphalt can arrange as a single molecule on the fiber's surface, forming a structural asphalt interface layer with a solid bonding force. At the same time, since the fibers and the surrounding structural asphalt are coated on the surface of the aggregate, the asphalt film on the surface of the aggregate increases, which is beneficial to slow down the aging of the asphalt and prolong the service life of the pavement. Foreign experience shows that the service life of SMA pavement can be extended by 30-50% compared with traditional asphalt pavement.
Stabilizing effect of PANF
The asphalt adsorbed by the criss-cross fibers increases the proportion of structural asphalt, reduces the free asphalt, and enhances the viscosity and softening point of mastic, thereby improving the stability of the SMA mixture.
Reinforcing effect of PANF
The fibers are randomly distributed in three dimensions in the mastic which can block the cracking of the mixture, thereby improving the self-healing ability and reducing the occurrence of cracks in the asphalt pavement. However, it should state that not all fibers have this effect. For example, since lignin and mineral fibers have insufficient tensile strength, they do not act as reinforcement, while polyacrylonitrile fibers have higher strength. Therefore, the strengthening effect is more pronounced.