Unsaturated polyester resins modified by nanometer ZrO₂ powder

The nano-ZrO₂/unsaturated polyester resin (referred to as nano-ZrO₂/UPR hereafter) was prepared with the 'reaction method' which the nano-ZrO₂ powder is added as a raw material upon synthesizing the unsaturated polyester resin (UPR) to form nano-ZrO₂/UPR. The optimal formula of the prepared nano-ZrO₂/UPR by the orthogonal experiments is: the molar ratio of the dibasic acid and the dibasic alcohol is 1 : 1, the saturated and unsaturated acid is 1 : 1, the amount of nano-ZrO₂ powder is 7%, the molar ratio of phthalic annydride and adipic acid is 1 : 1, the amount of benzyl peroxide (BPO) is 1%. The bending strength and impact strength of the nano-ZrO₂/UPR are 121.3 MPa and 10.1 kJ/m², increases 28.4% and 16.1% respectively as compared with that of UPR. So the simultaneous strengthening and toughening resin is obtained.