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In the formulation, there are two main purposes of surfactants. One is to improve the emulsifying ability of components, so that they can be more effectively mixed with each other. Two, during the foaming process, the control system has proper surface tension and produces a good bubble network structure. Therefore, it can also be called foam stabilizer. Polyester and polyether soft foam have different raw materials and properties, so the selection and dosage of surfactants are different. The commonly used surfactants for polyester polyurethane soft foam are: Witco 77-86 from Witco, emulphor el-719 from Antara, additive A-3 and A-9 from mabay, tegostab from Goldschmidt B-8300 and so on, usually in the formula dosage of 1 to 2.5 parts /100 polyol polymer. Its incorporation can effectively improve the emulsifying capacity of each raw material component, promote the stable growth of foam and prevent shrinkage. However, the efficacy of various surfactants is also different, such as A-3 can prevent foam shrinkage, while A-7 and A-9 can delay the gel time of foam surface and prevent foaming. crack.

The commonly used foam stabilizers for polyether polyurethane flexible foam are mainly Si - O - C - and Si - C - siloxane - olefin block copolymers. In the production of polyether polyurethane soft foam by one-step process, proper choice of foam stabilizer is one of the important factors to obtain excellent foam. The former is a hydrolytic foam stabilizer, which is easy to cause hydrolysis. In particular, its composition and other components are easy to cause hydrolysis when stored in other ingredients. The latter is non hydrolytic foam stabilizer. It is widely used and has excellent foam stabilizers. Its main products are DC-190 and DC-191 of Dow Corning, NIAX of UCC company. L-520, l-540, l-580, etc.; tegostab b-8110, b-8123, etc. of Goldschmidt. Their basic dosage in the formula is about 1% of polyether polyol dosage. Foam stabilizer will also increase when water foam is used and the water content is more than 3.5 mass fraction. The proportion of foam stabilizer usually increases by 0.2 parts per 0.5 additional water. In addition, in the formula, when CFC-11 is increased by 5 parts, the foam stabilizer should be increased by 0.2 to 0.5 parts.

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