Rotaxane-Silica Rubber Composition for Winter Tire Flexibility

The patent uses a composite material system combining rotaxane molecules with silica-coated fine particles and rubber components. The rotaxane provides flexibility at low temperatures through its unique molecular structure with cyclic molecules that can move along the straight chain, while the silica-coated particles provide reinforcing properties. This composite approach allows both flexibility and strength to coexist without the trade-off present in conventional single-material solutions.

The rotaxane structure exhibits local quality differentiation where the cyclic molecules provide flexibility through their movement along the straight chain, while the silica coating on the fine particles provides localized reinforcing properties. This spatial differentiation of functions within the rubber composition allows simultaneous achievement of low-temperature flexibility and overall reinforcing property.

The patent segments the rotaxane addition process from the rubber polymerization process. Instead of adding rotaxane during polymerization or modifying rubber components, the patent adds pre-synthesized rotaxane as a separate component to the rubber composition. This segmentation simplifies manufacturing by allowing rotaxane to be added in the same manner as other rubber additives, eliminating the need for complex modification processes.

The rotaxane is pre-synthesized and prepared as a ready-to-use component before being added to the rubber composition. This preliminary preparation of rotaxane with the desired molecular structure and properties allows it to be directly incorporated into the rubber compound without requiring subsequent modification steps, thereby simplifying the overall manufacturing process.