A method for treating sea sand with recycled polyurethane

Abstract

The invention discloses a method for treating sea sand by using recycled polyurethane, which is characterized in that an aqueous solution of a silane coupling agent containing amino groups on the molecule is added to a mixing material mixer, untreated sea sand is added, and after thorough stirring, solids are filtered out. Particles; add the mixture containing polyol, urea group and isocyanate into water to make a solution, add the obtained solid particles into the solution, and after thorough stirring, filter out the solid particles; mix the water-based asphalt with the obtained solid particles, fully Stir. The preparation method of the invention is simple, the whole process is carried out in an aqueous environment, the cost is low, and the processed sea sand has better performance, and can be used for building materials.

Description

technical field [0001] The invention relates to a method for preparing sea sand with a multi-layer coating structure by utilizing recycled polyurethane, and belongs to the technical field of material preparation. Background technique [0002] With the vigorous development of China's construction industry, the demand for concrete, which is an important part of construction, has also increased. Sand is the main component of concrete, and its consumption is increasing year by year. my country's annual demand for construction sand will reach 2.6 billion t, which is a huge challenge to the domestic sand source reserves. Nowadays, China's river sand resources are increasingly scarce, and the exploitation of river sand has also caused damage to the ecological environment. It has become extremely urgent to find alternative sand sources. Therefore, people have turned their attention to the abundant marine sand resources. Compared with river sand, sea sand has its own unique advantag...

AI Technical Summary

Problems solved by technology

This is because: 1) in the early stage of the reaction, the broken polyurethane needs to be pre-dissolved in the alcoholysis agent, and the alcoholysis agent is usually a small molecule alcohol with a functionality of 2-3, which has a limited dissolution efficiency for the polyurethane, resulting in the process Slowly; 2) The initial viscosity of the system is high, so that the probability of alcohol exchange reaction of polyurethane in the environment of alcoholysis agent is not high, resulting in slow degradation; 3) The characteristic functional groups of conventional alcoholysis agents are hydroxyl and ether bonds , it has no special promotion effect on the alcoholysis reaction of polyurethane, and an organic metal salt or tertiary amine organic catalyst is required to promote the reaction