The accelerator refers to a substance which can lower the initiator initiation temperature during the curing process of the polyester resin, and promote the organic peroxide to generate a radical at room temperature.
The critical temperature of the organic peroxide for unsaturated polyester resin is above 60 ° C, which cannot meet the room temperature curing requirement. Only in the presence of reducing agent (or oxidant), the activation energy of organic peroxide decomposition can be significantly reduced. The decomposition temperature of the organic peroxide can be decomposed at room temperature, and therefore, a system composed of an initiator and an accelerator is often referred to as an initiation system.
(1) According to its effect on the effect of organic peroxides: 1 an effective accelerator for peroxides; 2 an effective accelerator for hydrogenated oxides; 3 for all peroxides and hydroxides. Most of the promoters are reductive, and their principle of action is to promote the formation of free radicals in the peroxide and form a reaction chain.
(2) According to the initiator accelerator system classification: 1 dibenzoyl peroxide-tertiary amine system; 2 ketone peroxycarbon naphthenic acid initiator system.
(3) Combination accelerator: a combination of an accelerator and another accelerator will produce a synergistic effect, shortening the gel time and curing timeBack