Polyvinyl alcohol is a white flake, flocculent or powdery solid, odorless organic compound that is harmful to the body when inhaled or ingested and irritating to the eyes. And flammable, irritating, polyvinyl alcohol can be boiled into glue and used in the construction industry. This article specifically describes the composition analysis and production process of polyvinyl alcohol glue formula.
The formula of polyvinyl alcohol glue is prepolymer, diluent, auxiliary agent, etc. It is basically non-toxic. The ingredient in the glue is polyvinyl alcohol, which is a water-soluble plastic. When we add borax, boron atoms and oxygen atoms will string polyvinyl alcohol molecules together, so the properties of the original glue can be changed.
Technological advancements There are currently two main types of adhesives used in building decoration: solvent-based and water-based adhesives.
Solvent-based adhesives are mostly rubber-based adhesives, the most common being strong universal adhesives. In the past, the main quality problem of such adhesives was the excessive content of benzene and toluene. Now the formula has been improved, using low-toxic mixed solvents with less toluene content and strictly controlling the content of impurity benzene in raw materials, resulting in a significant increase in the detection pass rate.
The market share of polyvinyl formaldehyde (trade name 801 glue) in water-based adhesives is relatively high. In the past, the main problem was that free formaldehyde exceeded the standard. Nowadays, manufacturers strictly control the amount of formaldehyde used during synthesis or add additives to reduce free formaldehyde in the synthetic formula to make the product meet the requirements of national standards.
| Raw materials | Unit consumption (weight ratio) |
|---|---|
| polyvinyl alcohol | 6% |
| hydrochloric acid | 0.5-0% |
| glue reactants | 0.6% |
| base | 0.2-0% |
| glue film enhancer | 0.2-0% |
| Preservatives | 0.1% |
1. Pour 400kg of water into the reactor for the first time.
2. Heat to 60 degrees to open the mixer, add 60kg of polyvinyl alcohol, add 6kg of glue reactant, then add 5-6kg of hydrochloric acid, and measure PH = 2.
3. Put the steam directly into the reactor, heat it up to 97-100 ° C, completely dissolve the polyvinyl alcohol, and stir the heat preservation reaction at 98-100 ° C for 60-80 minutes.
4. Then add about 300kg of second water, cool the temperature in the reactor to about 70-75 ° C, slowly add 1kg of alkali (10kg diluted with water), and adjust the pH to 5-6.
5. Then add 2kg of glue film-forming enhancer (diluted with 3 times water), slowly add it to the reactor, and react at natural temperature for 30 minutes.
6. Add 100kg of water for the third time, then slowly add 1-1.5 kg of alkali (10kg diluted with water), adjust PH = 7-8, and react for 30 minutes.
7. Add 1kg of preservative, add water to 1000kg of glue, cool to 40 degrees, and discharge into barrels.
1. Add 100 to 150 kilograms of water to the reactor, heat up, start the mixer when the temperature reaches about 55 ° C and add 10 to 12 kilograms of polyvinyl alcohol, continue to heat up, stop heating when the temperature reaches about 98 ° C, keep stirring until the polyvinyl alcohol is completely dissolved, add 0.5 kilograms of formaldehyde and stir well.
2. Add 10 to 12 kilograms of acrylamide under stirring conditions (10 to 12 kilograms of acrylamide should be melted with 40 kilograms of water first), and stir well.
3. When adjusting the temperature to 62~ 70 ° C, slowly add 22~ 80 grams of the initiator amine persulfate while stirring (22~ 80 grams of amine persulfate should be dissolved with 400~ 480 grams of water first), and stir well.
The above is the analysis of the composition of the polyvinyl alcohol glue formula and the content of the production process of the polyvinyl alcohol glue formula. After reading the article, you should have a basic understanding of the polyvinyl alcohol glue formula. If you are interested in this area, you can continue to find relevant information and do further research.
