AbstractA series of thirteen polyethylene and ten polypropylene packaging films was studied by both the Handle‐O‐Meter and the dynamic tensile modulus apparatus, to discover how the stiffness of polyolefin films determined with the Handle‐O‐Meter depended on the modulus of the material and the thickness of the film. The polyethylene films included low‐, medium‐, and high‐density resins and ranged in thickness from 0.7 to 4 mils. The moduli of these films ranged from 2.5 X 109to 18 X 109dynes/cm.2The polypropylene films were made from several types of resins with moduli varying from 73 x 109to 54 X 109, and the thicknesses of these films ranged from 0.5 to 4 mils. When the logarithm of the ratio of stiffness to modulus was plotted as a function of the logarithm of the thickness of the film, as determined from unit weights and densities, a straight line was obtained with a slope of 2.5. This means that over a wide range of gauge and modulus the Handle‐O‐Meter stiffness of these materials,S(in grams), is related to the modulus,E(in dynes per square centimeter), and the thickness,t(in mils), by the equationS= 1.41 X 10‐9Et2.5. This result, which shows that the Handle‐O‐Meter stiffness of polyolefin films may be represented as a function of the thickness and the modulus as given by the dynamic tensile modulus apparatus, may be used to calculate a modulus value from any single Handle‐O‐Meter stiffness value or, alternatively, to reduce Handle‐O‐Meter stiffness measurements to a standard thickness. Conversely, this relationship may be used to predict the Handle‐O‐Meter stiffness of a film made fr
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