| 摘要 |
The mould material binding medium is for the production of foundry mould parts and consists of two components, which set cold, with polyurethane formation, in the presence of a catalyst. One component is a solution of a phenol-containing polyol with at least two OH groups (normally a phenolic resin), to which an organic peroxide is added, and the second component is a normally likewise dissolved polyisocyanate with at least two NCO groups. The ease of dismantling the mould parts after casting is considerably improved by the addition of the organic peroxide, without the other good properties of the binding medium being impaired. Preferably, about 1 to 30 % by weight of the solids content in the polyol solution is replaced with the peroxide. |
