【摘要】 采用气相色谱,在强酸(pH≈1)及脲和甲醛过量的条件下,通过测量脲、异丁醛和甲醛反应体系中异丁醛浓度随时间的变化,研究了脲-异丁醛-甲醛树脂的合成反应动力学,探讨了脲、异丁醛和甲醛的反应机理。结果表明,在反应体系中,脲、异丁醛和甲醛反应对异丁醛的反应级数为1,其反应表观活化能为77.05kJ·mol-1。脲、异丁醛和甲醛的反应为Mannich反应。更多还原

【Abstract】 Under the condition of strong acid (pH≈1), when the amount of urea and formaldehyde was excessive, the reaction kinetics of urea-isobutyraldehyde-formaldehyde resin was studied by means of the determination of the concentration of isobutyraldehyde in the urea, isobutyraldehyde and formaldehyde system with gas chromatography. The reaction mechanism of urea, isobutyraldehyde and formaldehyde was also discussed. The results showed that the reaction order of isobutyraldehyde was 1 and its apparent activation energy was 77.05 kJ·mol-1. This was a Mannich reaction.更多还原