Slip Resistance of Plastics

The coefficient of static friction is generally greater than the coefficient of dynamic friction on the same surface. 

Slip resistance is the property of surface that prevents slipping. In case of composite deck board, this property either reflects a nature of the matrix (a blend of plastic and hllers), or it could be designed by special means (brnshing, embossing, introdncing slip modihers). 

Friction is independent of the surface area, of speed (except when the objects are resting), and of temperature. This is in theory. However, in the real world, the contact area does matter. Furthermore, in the case of polymers, in general, and composite materials, in particular, the actual contact area is difficult to determine dne to deformations of the plastic. In reality, applied force, test temperature, sliding rate, and duration of the test, all are important. 

The concept of friction was recognized more than 300 years ago by Gnillaume Amon-tons (1663-1705). In his article De la resistance cansee dans les machines, published in 1699, Amontons first established that there existed a proportional relationship between friction force and the mutual pressure (or force) between the bodies in contact. That is why to obtain the coefficient of friction, we divide friction force by normal force. 

if it takes 5 lb of horizontal force to move a 10 lb block resting on a floor, the static coefficient of friction is 0.5. 

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