The thermal polymerization of petroleum resin generally heats the carbon nine fraction to about 260°C in the reactor. First, it forms a Diels-Alder addition intermediate from two polymerizable molecules,Petroleum Resin and then reacts with another polymerizable molecule.Petroleum Resin Generate two free radicals,Petroleum Resin and then initiate polymerization. Thermal polymerization method has simple process and high yield, but the reaction temperature is high, energy consumption is large,Petroleum Resin coking is easy,Petroleum Resin the color of the produced resin is dark, and the product grade is low. It is only used in industry to produce dark resin,Petroleum Resin and its products are mainly used for Rubber reinforcing agent, additive for concrete.
Catalytic polymerization of petroleum resins is a cationic addition polymerization reaction,Petroleum Resin mainly carbon nine monomers under the action of a catalyst to form a carbon positive ion active center to initiate chain polymerization, thereby synthesizing petroleum resins. The active center is greatly affected by the degree of dissociation of the ion pair. When the reaction medium and solvent are different,Petroleum Resin the active center is also different.Petroleum Resin Catalytic polymerization is the earliest and most widely used in the synthesis of petroleum resins.
Free radical polymerization is due to the existence of a large number of unsaturated bonds (lone pairs of electrons) in the nine-component carbon molecule,Petroleum Resin which forms free radicals under the action of an initiator and initiates chain polymerization. After the product is synthesized,Petroleum Resin a solid inhibitor is added to terminate the reaction. The initiators commonly used in the free radical polymerization of petroleum resins are peroxides and sodium fatty acids or their mixtures. The amount and ratio of initiators have a greater impact on product quality. The fundamental difference between cationic polymerization and free radical polymerization is the different nature of the end of the growth chain,Petroleum Resin that is, the different active centers. Its main performance is in the following aspects:
The growth chain of cationic polymerization is charged;Petroleum Resin the growth chain of cationic polymerization and the counter ion can be seen from the above. The composition of the carbon nine fraction is complex,Petroleum Resin and the boiling point is high, which is difficult to accurately separate. It is rich in unsaturated olefins,Petroleum Resin making the carbon nine fraction suitable for production. Raw material for petroleum resin.
