Coating process: 801 glue production process

Key tip: 801 glue is also known as polyvinyl formal amino glue The water resistance and adhesive properties are better than polyvinyl alcohol glue, and the residual formaldehyde content is much lower than 107 glue, which can meet the national compulsory standard (GB 18583-2001) The reason for the low content of residual formaldehyde in 801 glue is that the acetal glue is aminated with urea, so that the residual nail clothing reacts with urea, and the formaldehyde molecules are separated, so the formaldehyde smell is very slight, and the human nose can hardly smell it 1 Formula: Composition and dosage of polyvinyl alcohol dry product (brand 17 Paint knowledge how about Akzo Nobel Powder Coating Recommended introduction: powder coating is a kind of coating with different form from general coating, which is in powder form It is a new type of coating, because of its own advantages and more and more known by people Let's introduce Akzo Nobel Powder coating Akzo Nobel Powder coating is a cost-effective coating solution, which can be applied to different kinds of products After the treatment of static electricity and fire baking, a tough and durable coating surface will be formed, with the least impact on the environment Since the introduction of this technology, powder coating has been able to continue to maintain the Paint Home News: 801 glue is also known as polyvinyl formal amino glue The water resistance and adhesive properties are better than polyvinyl alcohol glue, and the residual formaldehyde content is much lower than 107 glue, which can meet the national compulsory standard (GB 18583-2001) The reason for the low content of residual formaldehyde in 801 glue is that the acetal glue is aminated with urea, so that the residual nail clothing reacts with urea, and the formaldehyde molecules are separated, so the formaldehyde smell is very slight, and the human nose can hardly smell it 1 Formula: it consists of 20kg 35% ～ 37% formaldehyde solution, 6.5kg 30% hydrochloric acid, 1.25Kg caustic soda (solid base), 0.25kg urea, 1.25Kg water, 200kg 2 The production process is as follows: 1 Prepare heating equipment, glue barrel, mixer, etc (2) The raw materials in the formula shall be weighed accurately (3) In another prepared barrel, add a proper amount of tap water, then add formaldehyde in the formula, stir and mix evenly to obtain formaldehyde diluent Standby (wear protective glasses and masks during formaldehyde dilution operation, and strengthen ventilation) (4) According to the above method, prepare hydrochloric acid diluent and caustic solution respectively for standby (5) In another prepared bucket, add 5kg of urea into tap water, stir and dissolve evenly to get the urea aqueous solution for standby (6) Deduct 30% of the tap water in the formula (the deducted water is used for acetal), add it to the glue pot, start the mixer (rotating speed: 80-120r / min), sprinkle it into the polyvinyl alcohol dry material, and mix it at room temperature for 20min, so that the polyvinyl alcohol can be fully wetted, expanded and dispersed, and at the same time volatilize the residual monomer in the polyvinyl alcohol dry material (7) After 20 minutes, steam is added to the glue pot to make the temperature of the material in the pot reach about 95 ℃ After continuous heat preservation and stirring for 1 hour, polyvinyl alcohol can dissolve completely Immediately stop heating and let it cool down (8) When the temperature of the material is reduced to about 90 ℃, add the diluted formaldehyde aqueous solution to the glue in a trickle way, and control the dosage of the formula within 15 minutes (mixing can't stop) (9) After the formaldehyde is added, add the diluted hydrochloric acid solution in a trickle way Add hydrochloric acid while measuring the pH value of the glue with the pH universal test paper When the pH value is 1.5, stop adding hydrochloric acid (10) When the reaction is near the end point, the glue will thicken rapidly, a large number of fine bubbles will appear, and the color of the glue will start to turn white At this time, the remaining 30% water in the formula should be immediately injected into the glue, and the human steam should be stopped to make the temperature drop rapidly The caustic soda water solution should be added to the glue as soon as possible In water, neutralize and make the pH value of glue 7.5 to stop formaldehyde condensation (11) Add urea aqueous solution for amination treatment (12) Continue to cool down When the glue is cooled to about 40 ℃, the material can be discharged and filtered with a 40 mesh screen to obtain the 801 glue of the finished product, which can be put in barrels for standby Home of coatings is specialized in coatings, diatom mud, paint coating, coating technology, fire retardant coating news and coating, diatom mud, paint coating, coating technology, fire retardant coating decoration knowledge and decoration renderings,