Rubber and plastic products are indispensable materials in modern industry and daily life. Their synthesis methods directly impact their performance and application range. Rubber and plastic products are primarily categorized into two main categories: rubber and plastic. While their synthesis processes differ, both involve the chemical synthesis and physical processing of polymer materials.
Rubber synthesis typically uses petrochemical raw materials, producing raw rubber through polymerization reactions. Natural rubber is derived from the latex of rubber trees, while synthetic rubbers such as styrene-butadiene rubber (SBR) and butadiene rubber (BBR) are produced through emulsion polymerization or solution polymerization. For example, emulsion polymerization of butadiene and styrene in the presence of an emulsifier produces SBR, a rubber with excellent elasticity. The synthesized raw rubber undergoes vulcanization, a process in which it reacts with a crosslinking agent such as sulfur under heating to form a three-dimensional network structure, thereby enhancing the rubber's strength and durability.
Plastic synthesis primarily relies on polyaddition or polycondensation reactions. Thermoplastics such as polyethylene (PE) and polypropylene (PP) are produced through the polymerization of ethylene and propylene monomers. Their molecular chains are free of chemical crosslinks, allowing them to be repeatedly heated and reshaped. Thermosetting plastics such as phenolic resins and epoxy resins undergo polycondensation under heating or catalytic conditions, forming irreversible crosslinked structures that impart greater heat resistance and mechanical strength. In recent years, green synthesis technologies, such as bio-based monomer polymerization and solvent-free polymerization, have emerged to reduce the environmental impact of rubber and plastic products.
Post-processing of rubber and plastic products is also crucial, including processing techniques such as compounding, extrusion, and injection molding to optimize the material's molding properties and end use. With advances in polymer science, synthetic methods for rubber and plastic products are evolving toward high efficiency, environmental friendliness, and high performance to meet the demands of emerging industries.