Internal crosslinking polypropylene carbonate waterborne polyurethane emulsion and preparation method and application thereof

Abstract

The invention belongs to the field of waterborne polyurethane and discloses an internal crosslinking polypropylene carbonate waterborne polyurethane emulsion and a preparation method and application thereof. The preparation steps are as follows: mixing polypropylene carbonate polyols and diisocyanate, increasing the temperature to 60 DEG C, adding a catalyst, increasing the temperature to 80-90 DEG C gradually, and performing thermal reaction for 2-3 h; adding a hydrophilic chain extender and performing thermal reaction; cooling to 60 DEG C, adding a crosslinking agent and performing reaction for 1-2 h; adding a proper amount of acetone to adjust viscosity; when the temperature is reduced to 35-45 DEG C, adding a neutralizer for reaction for 0.5-1 h; adding deionized water for emulsification, stirring for 0.5-1 h at a high speed; evaporating acetone to obtain the internal crosslinking polypropylene carbonate waterborne polyurethane emulsion. The internal crosslinking polypropylene carbonate waterborne polyurethane emulsion has superior cohesiveness and can be used as water paint and adhesive, an emulsion membrane prepared from the internal crosslinking polypropylene carbonate waterborne polyurethane emulsion has good transparency and high tearing strength.

Description

technical field [0001] The invention belongs to the field of water-based polyurethane, in particular to an internal cross-linked polypropylene carbonate water-based polyurethane emulsion and a preparation method and application thereof. Background technique [0002] Polypropylene carbonate polyol (PPC) is made of CO 2 A new type of aliphatic polycarbonate polyol resin, which is copolymerized with propylene oxide (PO), has abundant sources of synthetic raw materials and low price, and is of great significance to the comprehensive utilization of carbon dioxide. The content of carbonate structural units in PPC is relatively high, and the mole fraction is between 25% and 50%. The catalyst used in the reaction is cheap, the reaction operation is simple, and the reaction energy consumption is also low. If it is produced on a large scale, the production cost of PPC can be greatly reduced. PPC is a polymer with hydroxyl groups at both ends of the molecule. It is the raw material f...

AI Technical Summary

Problems solved by technology

The Chinese invention patent with the application number 201010565904.0 discloses a water-based polyurethane coating with polypropylene carbonate polyol as raw material and its preparation method. In this preparation method, an anionic hydrophilic chain extender is added in the prepolymerization stage, which easily leads to ion The uneven distribution of groups in the polyurethane molecular chain makes the emulsification effect poor