Method for producing high-viscosity adhesive from polyvinyl alcohol high-strength high-modulus waste fiber

The invention relates to a method for producing a high-viscosity adhesive from polyvinyl alcohol high-strength high-modulus waste fiber. The process comprises the following steps of: first, dissolving the polyvinyl alcohol high-strength high-modulus waste fiber into raw solution with steam; then adding water into the raw solution to dilute the raw solution and adjusting the pH to be 3 to 4; next, keeping the temperature of the raw solution at 90 to 93 DEG C and adding a modifier into the solution for modification at the temperature; and later on, performing acetalation, adjusting the pH to be 6 to 7, reducing the temperature and filtering the solution. By the method, the polyvinyl alcohol high-strength high-modulus waste fiber is subjected to modification and acetalation to produce the high-viscosity adhesive with viscosity of between 2,000 and 20,000mpa.s, so a new utilization way is provided for the polyvinyl alcohol high-strength high-modulus waste fiber; and thus the waste material is made profitable and