摘要 |
This Invention discloses the use of ascorbic and citric acid, their salts, ethers, acid esters and mixtures thereof in a method for the prevention of peroxide formation, and/or for decomposing peroxides already formed in polyethers. Hereby, the polyethers are made reactive to hydrosilylation by silanes and hydrosiloxanes. When the polyether treatment is done with mixtures of ascorbic acid and sodium ascorbate and allyl polyethers, the hydrosilylation product contains reduced levels of propanal. The copolymers prepared using the treated polyethers are efficient stabilizers of flexible polyurethane foams and rigid polyurethane and polyisocyanurate foams.
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