17 . Nov . 2023
Sponge foaming principle: the foam resin, foam additives and adhesive resin (so that the finished product has adhesion) mixed together; Foaming process is carried out. The foam sponge can be prepared by mixing 80 parts of vinyl acetate (EVA), 20 parts of APAO PT 3385, 20 parts of azodimethylamide, l9 parts of CaCO and 0.6 parts of diisopropylbenzene peroxide in the mold to foam, and then breaking the closed hole with mechanical force. Its density (d) is 0.028 g/cm and 25% compression hardness is 1.9 KPa
Common sponge foaming treatment method
1. Manual foaming method, which is the convenient method, will accurately weigh all sponge raw materials.
2. One-step foaming method. The polyether or polyester polyol and polyisocyanate, water, catalyst, surfactant, foaming agent, other additives and other raw materials are added in one step, mixed at high speed stirring after foaming.
3, prepolymer foaming method. Refers to the polyether polyol and diisocyanate prepolymer, and then add water, surfactants, catalysts and other additives in the prepolymer mixed under high-speed stirring for foaming, curing at a certain temperature can be matured.
4. Semi-prepolymer foaming method. Is to make part of the polyether polyol and diisocyanate prepolymer, and then the other part of the white and black materials, catalysts, water, surfactants and other additives are added, mixed under high speed stirring for foaming. This foaming method is similar to the prepolymer foaming method.
These are the four foam methods commonly used for sponges. After foaming, sponges can obtain better elasticity and water absorption, which can meet the needs of sponges in many industries.