Polymer matrix friction materials filled with bentonite of high specific heat were prepared by heatpress molding method.The effect of bentonite content on physical and mechanical properties and tribological behaviors of polymer matrix friction materials was investigated.Scanning electron microscopy(SEM)was employed to study the character of worn surface of different friction materials,and analyze the wear mechanism.The results show that the hardness of friction materials was decreased gradually with the increasing of the bentonite content,while the density and impact strength are linearly increased.The friction materials with mass fraction of less than 40% bentonite can greatly improve friction coefficient and reduce wear rate of friction materials.Particularly,the material with mass fraction 40% bentonite exhibits the best comprehensive properties.But the mass fraction of bentonite is more than 40%,the friction stability of friction materials is decreased,and the wear form is changed from main abrasive wear into main heat wear and abrasive wear.