Preparation method for organosilicone positive ion waterborne polyurethane

Abstract

The invention relates to a preparation method for organosilicone positive ion waterborne polyurethane. The preparation method comprises the following steps: (1) reacting diethylamine with allyl chloride in the presence of an alkaline to generate diethyl allylamine; (2) carrying ring opening on D4 under the effect of a catalyst and blocking by using HMM (hexamethylmelamine) to generate dihydro-blocked polysiloxane; (3) carrying out hydrosilylation reaction on dihydro-blocked polysiloxane and diethyl allylamine; (4) carrying out quaternization reaction on the production of the addition reaction and chloropropanol; and (5) generating a prepolymer through reaction between HMDI and PTMEG1000 and extending chains in water by using the quaternization product to generate the organosilicone positive ion waterborne polyurethane. The preparation method provided by the invention is simple and convenient to operate, mild in reaction condition, free of carbonization and products are easily separated and recycled. Firstly, polysiloxane with amido at two terminals is salified and then chains are extended, and the conventional step of salifying positive ions with an acid and then neutralizing is cancelled, so that use of a nitrogen-containing chain extender is reduced, the cost is saved and the problem that positive ion polyurethane gets yellow is prevented.

Description

technical field The invention relates to a preparation method of organosilicon cationic waterborne polyurethane, which belongs to the technical field of chemical industry. Background technique Cationic water-based polyurethane inherits the advantages of water-based polyurethane (WPU), such as non-flammability, non-toxicity, and environmental friendliness. At the same time, because the ions formed by it are quaternary ammonium salts, the particles are positively charged, which is the same as the charge carried by dust in the air, and has a certain It has good dustproof effect; its bonding performance is also good, and it can be used as an adhesive for some substrates; in addition, cationic water-based polyurethane also has a certain bactericidal effect and can be widely used as a fabric finishing agent. However, the process of salting the prepolymer is more complicated, the cost is higher, the product yellows seriously, and the emulsified product is sometimes not stable enou...

AI Technical Summary

Problems solved by technology

Aromatic isocyanates such as TDI and MDI synthesized water-based polyurethane are prone to yellowing, and aliphatic isocyanates such as HMDI can solve this problem well, but the use of chain extenders containing primary, secondary and tertiary amines also causes yellowing of water-based polyurethane important reason for

Due to the introduction of hydrophilic groups into the macromolecular structure during the synthesis of water-based polyurethane, and most of the water-based polyurethanes are linear polymers, although there are physical cross-links formed by hydrogen bonds inside, they lack chemical cross-links, so the mechanical properties of water-based polyurethane are relatively low. Poor, water resistance, solvent resistance, heat resistance and gloss are not ideal

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