The Effect Of Nano-Fiber Mineral On Properties Of Rubber And The Study Of Its Mechanism

In this paper, attapulgite which is a kind of natural fibrous silicate nano-clay minerals and environmental-friendly is chosen as raw material. Coupling agents are selected for the surface modification of attapulgite and the modified attapulgite/butadiene rubber composites have been successfully prepared using butadiene rubber as matrix and modified attapulgite as filler. Mainly studied modified mechanism of attapulgite with silane coupling agent Si-998 as an example and the reinforcement mechanism is analysised in details.Optimized the machining formulations of the composites by orthogonal experiment. According to the optimal formulations, the influences of modified attapulgite on the mechanical properties of the composites have been studied. The results shows that: When the addition amount is 60 phr, the maximum tensile strength reaches 8.9MPa, improved 4.84-fold. Using different kinds of coupling agents to modified attapulgite then fill-up in the butadiene rubber. Compared the mechanical properties of the composite. Results shows that silane coupling agent Si-998 has the best effect. When the amount is 3%, the tensile strength reaches the maximum as 11.37 MPa, improved 27.8% than unmodified attapulgite.Explored the effect and mechanism of attapulgite modified by silane coupling agent Si-998. SEM shows that the dispersion of modified attapulgite has been significantly improved, forming nanoscale materials. FTIR testing shows that the hydroxyl groups of the attapulgite modified surface produce condensation reaction with silane coupling agents to generate new Si-O bonds. This concludes that between the silane coupling agent and attapulgite have undergone a chemical link. XRD analysis shows that the coupling coated on the surface of the attapulgite fiber and the organic functional groups formed by the reaction don’t make a significant effect on the crystal structure of attapulgite. The surface energy test can be drawn: When the amount of coupling agent is 3%, attapulgite reaches saturated modification. The mass fraction of silane coupling agent which chemically linked with the saturation modified attapulgite could be accurately calculated as 3.12% via TGA analysis. Established a mathematical model which coupling physically coated attapulgite and gives the mathematical derivation formula.Systematically studied the reinforcement mechanism of the rubber which is filled with attapulgite modified by silane coupling agent Si-998. XRD testing speculates that there are some combined rubber covering on the surface of attapulgite fibers. Combined rubber could be found from the photos of TEM, which verified the XRD analysis. Established the models that attapulgite nano short fiber reinforced rubber. Combined the stress-strain curve during the stretching process and its first derivative curve, indicating that there are three states in the stretching process. Rationality of the models can be verified via SEM analysis and EDS analysis of the composite rubber tensile fracture. Discovered the percolation phenomenon during the rubber nano-enhanced process and explained its reasons. Then established a mathematical model. Presented the mathematical formula of the average spacing between the enhancer particles and the particles diameter distribution. It can theoretically calculate the critical volume fraction of enhancer when percolation phenomenon occurs.