Editor On When the rubber test piece is deformed under the reciprocating cycle force, even if the reciprocating speed is equal, The stress and strain curves do not coincide (as shown in Figure 4-6). In the figure, OA is a tensile curve and AC is a retraction curve. The area covered by the OAB represents the mechanicalContinue Reading
Editor On 1. Rubber molecular structure Where the molecular chain is soft and the glass transition temperature is low, the fluidity is generally good. 2. The molecular weight should not be too high. If the average molecular weight is more than 1 million, the molecular chain entanglement will be intensified, which is not conducive to flow. NaturalContinue Reading
Editor On The rubber is in a high elastic state at normal temperature. When the temperature falls below its crystallization temperature, the rubber enters a crystalline state. When the temperature rises to a certain critical point (which varies with the rubber type), it changes from a high elastic state to a viscous flow state, and becomes aContinue Reading
Editor On When the rubber stopper is subjected to an external force (whether tensile or compressive), a certain deformation is inevitable. However, once the external force is removed, the rubber plugs will exhibit an inertial instinct, that is, it will return to its original state in both size and geometry, but it cannot be completely restored toContinue Reading
Editor On (1) Glue Crystalline rubbers, such as NR and CR, have high inter-intermolecular forces and strong mutual entanglement, so they are self-adhesive. Non-crystalline rubbers such as SBR, BR, and NBR are the second, and IIR and EPDM are the worst. Their adhesive force (kg / cm) compared below: NR(12.5)>SBR,BR(5.6)>IIR(3.7)>EPDM(1.7-2.5) (2) Additives Due to the small molecularContinue Reading