Determination of shear modulus and Poisson's ratio of polymers and foams by the anticlastic plate-bending method

In this paper, results of research towards development of a test method for the determination of shear modulus and Poisson's ratio of polymers and structural foams are presented. Through this work, a test apparatus was developed which employed anticlastic plate bending behaviour; this device was used for calibration tests on steel and aluminium samples and for tests on a number of polymers, including high density Polyethylene (PE-HD), unplasticized Polyvinylchloride (PVC-U), Polymethylmethacrylate (PMMA) and rigid Polyurethane (PUR) foam. Long-term tests and temperature-dependent tests on PVC-U, PE-HD and PMMA samples were also performed. In some cases, results of the tests with the anticlastic bending method were compared with those obtained from tests carried out with the torsion pendulum method. For theoretical simulation, an analytical formula and a number of finite element analyses were performed. Through these simulations, values for the short-term, long-term and temperature-dependent shear modulus and Poisson's ratio of PE-HD, PMMA, PVC-U and PUR foam were obtained.