Polypropylene crack resistant fiber is a high-strength bundle monofilament organic fiber formed from fiber grade polypropylene through special processing technology. It has inherent  resistance to strong acid and alkali, weak thermal conductivity and extremely stable chemical properties. Adding it in the mortar or concrete can effectively control the micro cracks caused by temperature changes in the initial mould shrinkage stage of mortar and concrete, prevent and restrain cracking, and greatly improve the performance of crack resistance, impermeability, impact resistance and seismic capacity of concrete.