Analysis And Treatment Of Wallpaper Stickies And Research On Properties Of Its Recycled Pulp

Non-woven wallpaper as one kind of indoor decorating materials is becoming more and more popular in market,with the growing scale of production,the problem of recycling secondary fibers has become increasingly acute.This paper took it as the research objective,finding that the key to recycling wallpaper was the treatment of stickies.Through the analysis and processing of wallpaper stickies,the conclusions were drawn as followings.?1?Non-woven wallpaper had high strength and dimensional stability,and also had good water resistance and bulk weight.The fibers were composed of synthetic fiber and plant fiber.Filler containing titanium dioxide could improve the optical index and flame retardancy.?2?Polyacrylic acid was the main ingredient of stickies,as adhesives it mainly depended on spraying between fibers including polypropylene fiber to form bonds,as the water resistance agent it was used to make the plant fiber surface lose or reduce hydrophobicity.?3?The polypropylene acid was a kind of non-crystalline,Begins to melt at about 90 ? and starting pyrolysis at 300?.In this experiment,the content of the stickies was 9.85%,which was regarded as the theoretical value in wallpaper.?4?Mechanical treatment alone cannot change the water resistance of wallpaper,it is not desirable to use this method to deal with the adhesive because the polyacrylic acid belonged to weak acid.In the alkaline environment,the optimal treatment process was as follows: pulp concentration was 10%,the temperature was 90?,the concentrations of NaOH and H₂O₂ were 10% and 8% respectively.After one hour of pre-impregnation,high-speed dispersion machine was used to dissociate fiber for 2 hours at 2000 r/min.Through this process,the percentage of recycled pulp could be reach 88.52%,and the removal rate of stickies was 92.66%.?5?Stickies removal mechanism was that NaOH and H₂O₂ could invade into the stickies,thereby reducing the surface energy of stickies,and causes the stickies thereby lose their stickiness to spread on the surface of fibers.Through further interaction,large stickies were broken down into smaller stickies which could be dissolved in Water,ultimately bond points broke,and the fiber under the action of shearing force could be better ease.?6?Most fiber of the recycled pulp was plant fiber,synthetic fiber was almost trapped in the sieve of 12 mesh.Through the observation by microscope,recycled pulp,that also was,plant fiber,whose stickies basically disappeared on the surface of fiber,could be used for pulp again.