Enclosed polyurethane performed polymer for formulating low-temperature plasticizing PVC plastic colloidal sols and method of producing the same

Abstract

The invention relates to a close type polyurethane prepolymer used for preparing low temperature plasticizing PVC plastisol, which can improve the adhesion of the PVC plastisol on an electrophoresis paint plate and simultaneously reduce the plasticizing temperature of the PVC plastisol so as to reduce energy consumption. The polyurethane prepolymer is characterized in that: the polyurethane prepolymer is polymerized by polyisocyanate and a polyhydroxy compound with the generation terminal group of the semi-prepolymer of - NCO and a sealant is applied to blocking the semi-prepolymer so as to obtain the close type polyurethane prepolymer. The preparation method is as follows: 50 portions to 500 portions of a diluent are added into a three-necked reactor, stirred and heated to 75 DEG C to 80 DEG C, then 100 portions to 400 portions of polyisocyanate are added, 250 portions to 800 portions of the polyhydroxy compound are added slowly, reaction lasts for 3 hours to 4 hours, then 10 portions to 200 portions of the sealant and 0 portion to 2 portions of a catalyst are added slowly and the reaction lasts for 2 hours and 3 hours.

Description

technical field [0001] The invention relates to the field of polyurethane prepolymer and its preparation method, in particular to a closed polyurethane prepolymer for preparing low-temperature plasticized PVC plastisol and its preparation method. Background technique [0002] PVC plastisol is widely used in the automobile industry, and its typical products are PVC anti-stone impact vehicle undercoating and PVC weld seam sealant. The plasticizing temperature required by PVC plastisol products on the market is mostly around 140°C, and high-end products The plasticizing temperature can be as low as 130°C. Automobile manufacturers need to reduce the temperature of the drying room for the purpose of energy saving and emission reduction. Therefore, it is necessary to use it to improve the adhesion of PVC plastisol on the electrophoretic paint board and reduce the PVC plastisol at the same time. Low-temperature plasticizing PVC plastisol with a certain plasticizing temperature; clo...

AI Technical Summary

Problems solved by technology

[0002] PVC plastisol is widely used in the automobile industry, and its typical products are PVC anti-stone impact vehicle undercoating and PVC weld seam sealant. The plasticizing temperature required by PVC plastisol products on the market is mostly around 140°C, and high-end products The plasticizing temperature can be as low as 130°C. Automobile manufacturers need to reduce the temperature of the drying room for the purpose of energy saving and emission reduction. Therefore, it is necessary to use it to improve the adhesion of PVC plastisol on the electrophoretic paint board and reduce the PVC plastisol at the same time. Low-temperature plasticizing PVC plastisol with a certain plasticizing temperature; closed polyurethane prepolymer is a kind of polyurethane resin, and polyurethane resin is a polymer compound with unique properties and multiple uses, and its molecular chain contains polar poles High isocyanate group (-NCO) and carbamate (-NHCOO-) have excellent adhesion ability to materials containing active hydrogen, and hydrogen bonding occurs between materials to be adhered, which strengthens the intramolecular force and makes The adhesion is stronger, so it is often used as a tackifier for PVC plastisols to improve the adhesion of PVC plastisols on electrophoretic paint panels, but it cannot achieve the effect of reducing the plasticizing temperature of PVC; prepolymers on the market generally use The main material is isocyanate monomer or its adduct, which is directly reacted with a blocking agent to prepare a prepolymer, which is mainly used as a curing agent for paint