Reinforcement Of Ethylene-Propylene-Diene Monomer Rubber With Carboxylic Acids Modified Nano Calcium Carbonate

Calcium carbonate has been mainly used as filler to reduce the cost of rubber products. With the development of technology in superfine filler production and especially in surface modification, calcium carbonate used as reinforcing filler has caught great attention. As inert inorganic filler, nano calcium carbonate (NCC) has not exhibited the similar reinforcing effect as traditional reinforcing fillers such as carbon black till now. Lacking of reactive group on the surface, NCC cannot chemically react with rubbers in a simple mixing procedure. Poor filler-matrix interface interaction generates interface defect and results in the normal reinforcing ability of NCC to rubber.In the dissertation, nano calcium carbonate, which was in situ modified with methylacrylic acid (MAA), was used to reinforce ethylene–propylene–diene monomer (EPDM). The mechanical properties, crosslinking structure, and filler-matrix interface interaction of EPDM/NCC vulcanizates were studied. The reinforcement mechanism of MAA in situ modified NCC was also investigated. MAA remarkably improves the reinforcing effect of NCC on EPDM vulcanizates. 2 wt% MAA with respect to the NCC weight increased the tensile strength of the vulcanizates from 16.9 MPa to 25.6 MPa. Other mechanical properties including tensile modulus, tear strength and elongation at break are also increased.Infrared transmission spectrum (FTIR) was used to determine the chemical reactions among MAA, NCC and EPDM. Ionic bond formed between MAA and NCC in the mixing procedure. In the curing procedure, dicumyl peroxide (DCP) initiated...