Preparation And Performance Study Of Toughening Epoxy By Bitumen

Epoxy as the most important class of thermosetting polymer has been extensively used in structural applications like fiber-reinforced composites because of their outstanding mechanical, chemical, thermal and electrical properties. However, epoxy has a critical defect, brittle in nature, so it has low impact strength, which limits their many end-use applications especially in the fields of aeronautics and astronautics. So improving its toughness is a key fact for broadening the application of epoxy. Traditional toughening methods include liquid rubbers, thermoplastics and so on. But they all have their own inevitable defects. This paper reviewed the toughening methods at home and abroad, and then put forward a new idea of toughening epoxy resin-using asphalt as the new modifier.Bitumen is commonly used as the road paving material, which contains asphalt, colloid, aromatic and saturated component. Epoxy is now widely used as a modifier for bitumen, but using bitumen to toughen epoxy has not been studied yet. The main content of this paper includes:Mix different loadings of bitumen with three kinds of epoxy, exploring whether bitumen has the toughening effect to epoxy. Impact strength and mechanical properties of epoxy/bitumen hybrids with different bitumen contents are studied. FT-IR is used to analyze whether epoxy and bitumen has chemical reaction in the in the interface and SEM is used to analyze the microstructure of section.The tests results show that with the addition of only2%or3%bitumen to epoxy, maximum improvements in impact strength of77%,106%and100%are obtained; Tensile strength and are improved14%,6.5%and8%; bending strength are improved25%,24%and15%separately. And it has no significant effect on tensile modulus.The.microscopic phase structure formed in epoxy/bitumen hybrids is similar with that in epoxy/rubber hybrids, which is called sea-island structure. Through SEM pictures, bitumen particles gather together after the content of2%. And compatibility between bitumen and epoxy is a key aspect that affects the interface bonding of the hybrids. So maleic anhydride is used to improve the compatibility between bitumen and epoxy.Different addition of bitumen modified with maleic anhydride is than add to epoxy as toughening agent. Compact energy, mechanical properties and thermal decomposition temperature are test. The result shows that with the bitumen addition of4%, maximum improvement in impact energy, tensile and bending strength of150%,11%, and29%are obtained. The compatibility between epoxy and bitumen get better through SEM pictures. It shows that chemical interactions are occurred between bitumen and epoxy through FT-IR.