Polypropylene chopped strands for dry mix

Monofilament polypropylene fiber is also called engineering fiber, concrete fiber,anti-crack fiber, crack control fiber,synthetic fiber or plastic fiber,etc.It is a kind of high intensity bunchy monofilament fiber mainly made of PP raw meterial by special technique.

Adding Micro PP fiber into the concrete or mortar, can effectively prevent temperature change, microcrack caused by plastic and dry shrinkage,etc, thereby prevent crack and improve effectively anti-crack,anti-infiltration, anti-concussion and anti- shock of the concrete. 

Polypropylene (PP) chopped strands for dry mix applications are typically in lengths of 3mm, 6mm, or 12mm, which are ideal for mortars and screeds. These fibers are designed to improve crack resistance and durability in cement-based products,Polypropylene fibers are a popular choice for reinforcing concrete and mortar due to their high performance and resistance to the alkaline cement environment.                                

They are used widely in roads,bridges,underground waterproof projects and roofings,walls,pools,basements of the industrial civil construction. 

The Physicochemical Properties of Micro PP Fiber:

The General Introduction of the Fiber Reinforced High Performance oncrete(FRHPC)
       The cement concrete material is the most widely-used man-made construction material nowadays. But it tends to produce crack as a result of its brittleness, and the anti-stretch intensity of the ordinary high-strength concrete is far lower than its anti-compression intensity, so the brittleness damage easily happen, which will influence the lifetime of the project.

With the rapid development of the city construction of our country and the continuous innovation of the technique of architecture, the high-rise buildings,the skyways,the underground traffic make requests to the performance of the concrete, e.g. high anti-stretch and anti-compression,high toughness,high anti-infiltration and anti-crack,easy to construct and so on, as a result, the FRHPC arised.

FRHPC, that is, adding synthetic fiber or steel fiber or glass fiber or carbon fiber etc. into the ordinary concrete, which embodied the logos of composite material design. Especially the synthetic fiber reinforced concrete, not only remain the high anti-compression the concrete inhered, but also reinforce anti-crack, anti-infiltration and toughness, that make it meet the demand of nowadays high and new construction better.

The Function of Reinforcement of Micro PP Fiber for the Concrete  
1) Anti-crack function:
PP fiber was distributed in the concrete in 3D stereo, which reduces the stress concentration of the microcrack point , weakens or removes the tension caused by sun crack of the concrete or mortar, further prevents the happen and development of the microcrack. For plastic concrete, PP Fiber can support the aggregate, reduce and prevent the isolation tendency of the concrete, so lessens even prevent the happen of crack on surface.  

2) The improvement of anti-infiltration performance:  
PP Fiber can lessen the plastic crack of concrete effectively, and prevent the development and run-through of the crack. The evenly distributed fiber monofilament formed a support system, prevent the surface bleeding and the aggregate fall, decrease the bleeding of concrete, reduced the bleeding passage of concrete, lessened the hole rate greatly, consequently prevent infiltration of the concrete obviously .  

3) the improvement of anti-freezing and thawing:  
PP fiber can decrease effectively anti-compression stress concentration in the concrete caused by several times’circulation of freezing and thawing, which prevent the further extend of the microcrack.In addition, the increase of the anti-infiltration of the concrete surely makes for the improvement of freezing and thawing.  

4) the improvement of toughness and anti-shock: 
PP Fiber can help to absorb the kinetic energy ,which produced when the component of concrete is shocked, moreover due to the anti-crack effect of the fiber, when the concrete is shocked, the fiber can prevent the rapid extend of the inner crack, consequently increased the toughness and anti-shock of the concrete.

5) the improvement of durability:   
The excellent anti-crack effect of the PP Fiber reduce the happen and development of the crack greatly.The reduction of the inner hole rate makes the infiltration and corrosion from the water,the chemical substance,theChloride salt as well as other outside factors slow down, i.e. because of the great reduction of the crack, the channel that provided by the crack which would make the function of damage and corrosion infiltrate even extend become