摘要
本文以差热扫描量热法(DSC)分别研究了脲醛(UF)胶、聚异氰酸酯(PMDI)胶以及它们的混合液的加热固化过程。结果表明,PMDI和UF在105～110℃发生放热固化反应。此外,PMDI与水在120～125℃发生剧烈的放热反应。PMDI的反应活性受介质酸度影响较大,介质pH值越低,PMDI的反应性越小,或几乎被抑制。
The curing processes of urea-formaldehyde(UF) resin, polydiphenylmethane diisocyanate (PMDI) and their mixtures were examined respectively by differential scanning calorimetry (DSC). Results showed that the reactions between the UF resin and PMDI occur at the temperature of 105～110℃. PMDI intensely reacts on water when the temperature reaches 120～125℃. However, the reaction activeties of PMDI is effected by the acidities of the medium. The lower the pH value of medium, the worse the reactiveness of PMDI.
出处
《木材工业》
北大核心
1993年第2期2-6,共5页
China Wood Industry
关键词
差热分析
脲醛树脂
聚异氰酸酯
人造板
胶粘剂
固化过程
Differential scanning calorimetry (DSC)
Urea—formaldehyde resin
Polydiphenylmethane diisocyanate (PMDI)
