The relationship between the hydrogen bond network,intermolecular binding energy as well as other factors in the polyurethane/polyethyl methacrylate (PU/PEMA) damping material and the damping properties of the material was studied by means of molecular dynamics simulation and experimental verification.The results of the molecular dynamics simulations revealed that there were two types of hydrogen bonds in the PEMA/PU damping material.They were “Type A” hydrogen bond between the carbonyl group in PU and the amine group,and “Type B” hydrogen bond between the amine group in PU and the carbonyl group in PEMA.As the ratio of PEMA increased,the free volume fraction of the system decreased,and the binding energy also declined gradually.At the same time,the number of Type B hydrogen bonds in the system increased and the number of Type A hydrogen bonds decreased.When the mass ratio of PU to PEMA was 7∶3,the number of hydrogen bonds in the system reached the maximum value,and the existence of the hydrogen bond network in the system was confirmed by infrared spectroscopy.The results of dynamic mechanical analysis showed that the damping peak value of the material reached the maximum value of 051 when the mass ratio of PU to PEMA was 9∶1,and the effective damping temperature range of the material reached 992 ℃ when the ratio of PU to PEMA was 6∶4.According to the calculation results of the binding energy and the statistical analysis for hydrogen bonds,it could be concluded that Type A hydrogen bonds have stronger binding ability to molecular chains than Type B hydrogen bonds.Type A hydrogen bonds are the main factor affecting the damping peak value,while Type B hydrogen bonds are beneficial to broaden the effective damping temperature range of the material.