机构地区: 华南理工大学化学与化工学院
出 处: 《涂料工业》 2013年第2期39-42,共4页
摘 要: 以自制的Mannich碱催化剂C-0116合成甲苯二异氰酸酯(TDI)三聚体聚氨酯固化剂,研究了合成工艺条件。在氮气保护下,向TDI和乙酸丁酯混合溶液中滴加Mannich碱催化剂,控制温度、时间、用量等条件,最终得到TDI三聚体。实验结果表明:该催化剂催化活性高,在40℃下,以滴加方式催化反应,8 h可达到反应终点,—NCO含量在7%以上,由气相色谱测定得到的三聚体中游离单体含量低至0.7%;实验中添加适量的十二醇进行改性处理,大大改善了三聚体的二甲苯容忍度。 A self- made Mannich base catalyst C -0116 was used in synthesis of the polyurethane cu- ring agent TDI trimer. And the synthetic conditions were discussed. When the Mannich base catalyst was added into the mixture of TDI and butyl acetate under purge of nitrogen, and the reaction conditions like temperature, time, quantity were controlled, TDI trimer was synthesized. The experiment results indicated that this catalyst showed a high catalytic activity. The TDI trimer with low free monomer content could be ob- tain at 40 ℃ with dropwise addition of catalyst for 8 hours to reach the end point. The --NCO content was a- bove 7% and the free monomer content was lower than 0. 7% determined by gas chromatography. Incorpora- tion of dodecanol for modification could greatly improve the xylene tolerance of the TDI trimer.
领 域: [化学工程]