Aliphatic series polyisocyanurate preparation method

Abstract

An aliphatic series polyisocyanurate preparation method includes the following steps: isocyanate and complex catalytic system formed by quaternary ammonium salt and inert alcohol solvent are added to a static mixer to lead isocyanate to have polymerization reaction, and then the formed product flow is transferred to a dynamic reactor for continuing the polymerization reaction; the reaction solution obtained in the polymerization reaction is processed by a second-level evaporator to obtain polyisocyanurate product. The preparation method can well control the reaction activity of the catalyst, causes the trimerization of isocyanate to be carried out in mild conditions and accordingly obtains tripolymer products with very high quality.

Description

technical field [0001] The invention relates to a preparation method of aliphatic isocyanate trimer, in particular to a preparation method of aliphatic polyisocyanurate. Background technique [0002] As early as more than 100 years ago, the famous German scientist Hoffman discovered that three isocyanate groups can react to form isocyanurate. In the 1960s, the industrialization of Bayer's isocyanurate, its HDI trimer has a stable isocyanurate heterocyclic structure in the molecule, so it has low volatility, low toxicity, and good storage stability. Compared with biuret, it has more excellent weather resistance, heat resistance, light stability, low viscosity and high product hardness, so it is widely used in polyurethane materials. [0003] HDI isocyanurate can be used to prepare polyurethane coatings, which have good weather resistance, chemical stability and long pot life. The storage stability of HDI trimer is especially better than that of biuret. At the same time, th...

AI Technical Summary

Problems solved by technology

At the same time, the yellowing resistance of the trimer in the product placement is obviously better than that of biuret and other adduct products, but in the process of preparing the trimer, there are the following problems: the catalyst is easy to remain, which affects the later application ; The obtained adduct is easy to turn yellow, which affects the performance of the later product; the product obtained from the trimer has a high viscosity, which affects the construction performance

The main problem of the trimerization reaction is that the reaction heat is too large, it is difficult to control the reaction process, and there are too many additional catalysts and additives. Undesirable by-products, and in the post-processing process, these trace components cannot be eliminated, thereby affecting the application properties of the final trimer