Application of polyurethane catalyst in the synthesis of rigid sheets
It specifically relates to a catalyst for the preparation of polyurethane and the application of this catalyst, which belongs to the technical field of polyurethane material synthesis.
Polyurethane is a collective name for a polymer compound containing repeating urethane groups in its main chain. This polymer material can be used in the manufacture of rubber, rigid and soft foam, adhesives, coatings, paints and other products, and is widely used in construction, automotive, light industry, textile, petrochemical, metallurgy, electronics, national defense, medical, machinery and many other fields for its excellent wear resistance, impact resistance, UV resistance and high and low temperature resistance. and many other fields.
Polyurethane materials are made of polyisocyanate, polyol and other stabilizers as raw materials, which are catalyzed by catalysts at a certain temperature. products.
To this end an amine catalyst for the preparation of low emitting, recatalytically stable flexible polyurethane foams, which includes at least one reactive amine catalyst and at least one organic potassium, zinc and/or tin compound, has a good catalytic activity. However, the use of tin compounds as a component of the catalyst in the above catalysts makes organotin-based catalysts contain incomplete reactive dibutyltin, etc. Such byproducts tend to cause malformation or chronic poisoning of living organisms, and therefore have been included in the list of controlled uses in developed countries such as the EU. However, if the tin compounds are replaced by other organic compounds such as potassium and/or zinc without the addition of organotin compounds, the catalytic activity of the catalysts decreases significantly, and on the one hand, even if the reaction temperature is increased, the decrease in reaction rate and the increase in reaction time cannot be avoided, and on the other hand, if the reaction rate is similar to that of the tin-containing catalysts, the amount of catalyst has to be increased, for example, in the synthesis of synthetic leather slurry, the use of organo For example, in the synthesis of synthetic leather paste, the use of organic bismuth to completely replace dibutyltin laurate, the dosage will reach 4-5 times of the original dosage; and either the former solution of extending the reaction time and increasing the reaction temperature, or the latter solution of increasing the dosage of catalyst will lead to the increase of the synthesis cost of polyurethane materials to varying degrees, even so, the physical properties of polyurethane materials synthesized by its catalysis, for example, tensile strength, tear strength are significantly reduced, and furthermore, the When using formulations that do not contain tin compounds in the above-mentioned literature, they also tend to yellow the synthesized light-colored polyurethane materials; in addition, in the case where the raw material formulations for synthesizing polyurethane contain water, the organic compounds of bismuth or zinc are deactivated by hydrolysis, making the storage period of the combination materials shorter.
To this end, the technical problem to be solved is that the catalysts without tin organometallics in the prior art not only have low catalytic activity but also poor performance of the synthesized polyurethane materials, so as to provide an environmentally friendly polyurethane catalyst with high catalytic activity and good physical properties of the prepared polyurethane materials for the synthesis of rigid polyurethane materials.
