The Preparation And Performance Of Rubber With Multiple Cross-linked Networks

Rubber is the soft material which can be irreversible deformed,and that is indispensable to the national economy and daily life.It has been widely used in tires,sealing,shock absorption,shoes,and other areas of the industry.It is necessary to enhance the rubber properties,because the poor mechanical properties of the unreinforced rubber cannot meet the application requirements in most cases.This work designs the rubber with multiple cross-linked network to enhance the mechanical properties,extend the working life and guide the development of new rubber materials.1.The properties of styrene butadiene rubber filled with silica which modified by different content of silane coupling agent was investigated.The mechanism of silane coupling agent can coupling with silica and participate with rubber vulcanization is the key to enhance the performance of rubber.Because this hybrid network can inhibit the production of material damage structure.The results of Infrared spectrometer?IR?test proved that the silane coupling agent successfully grafted to the surface of nano silica.The transmission electron microscope?TEM?results found that silica particles have good dispersity in the rubber matrix.The grafting density of silane coupling agent was analyzed by the thermogravimetic analysis?TGA?.And the mechanical properties were tested.We found that the tensile strength of samples was proportional to the density of the grafted silane coupling agent.With the increase of the content of silane coupling agent,the crack growth rate of rubber material under dynamic load decreased obviously.In microscopic perspective,the mechanism of the damage structure of the hybrid network rubber under external force was explained by the synchronous radiation small Angle ray scattering instrument.It was found that the growth of the nano hole was not obvious,which was beneficial to inhibit the production of crack damage.2.The properties of elastomer with metal coordination between Fe³⁺and-COOH and the properties of rubber network with covalent bond and this metal coordination were investigated.The physical gel was successfully prepared,which had good tensile property and self-healing function.With the increase of Fe³⁺,the number of crosslinking point increases that results in the enhancement of tensile strength.The tensile properties of the ligand elastomers with physical crosslinking were also increased with the increase of Fe³⁺content,and the glass temperature increased with the increase of crosslinking density that tested by dynamic mechanical analysis?DMA?.The introduction of this coordination network into covalent sulfide nitrile rubber resulted in the enhancement of tensile strength of the multiple cross-linked rubber.The results of DMA shown that the storage modulus increased with the increase of physical crosslinking,and the plateau modulus range also widen with the increase of physical crosslinking.The study of the mechanism of nano-orifice in rubber material could provide a theoretical basis for the preparation of toughened rubber materials.Using the metal coordination between the functional groups of carboxyl nitrile and mental iron could prepare the pure physical crosslinking and the rubber elastomer with good properties.The rubber with multiple cross-linked network would be helpful to guide the development of new rubber materials.