● Linear structure: the general structure of unvulcaniz […]
● Linear structure: the general structure of unvulcanized rubber. Due to its large molecular weight, it has a fine mass without external force. When an external force is applied and the external force is removed, the entanglement of the small group changes, and the molecular chain rebounds, resulting in a strong tendency to recover. This is the origin of the high elasticity of rubber.
● Branch structure: The aggregation of the branches of the rubber macromolecule chain forms a gel. Gels are detrimental to rubber performance and processing. During compounding, various compounding agents often cannot enter the gel area, forming a local blank, forming no reinforcement and cross-linking, and becoming a weak part of the product.
● Cross-linked structure: Linear molecules are connected to each other through the bridging of some atoms or groups of atoms to form a three-dimensional network structure. With the progress of the vulcanization process, this structure is continuously strengthened. In this way, the free-moving ability of the chain segment is reduced, the plasticity and elongation are reduced, the strength, elasticity and hardness are increased, and the compression set and the swelling degree are decreased.