Literature says that Tensile Strength of 30% glass fiber filled PP is around 52 MPa. Now I suppose that some ASTM procedure is followed to measure the Tensile strength. But the ASTM procedure does not tells us what is the length of the glass fiber in the polymer matrix. The reason why I am asking this is because the tensile strength of the polymer composite is directly related to the length of the fiber.
Where can I know what is the length of the glass fibers being used?
( Besides I have seen different values of tensile strength of 30% glass fiber filled PP in different literature sources. Does that suggest that the fiber length are different in the different sources)