Preparation method of urea-formaldehyde resin from straw ethanol byproduct

[0017] A preparation method of straw ethanol by-product urea-formaldehyde resin glue, the preparation steps are:

[0018] Step 1: Add 36.8wt.% formaldehyde solution, water, pre-compression modifier, the first batch of urea, the first batch of melamine and the first batch of straw ethanol by-products into the reactor, where the water / formaldehyde mass ratio is 0.40 ~1.54:1, the mass ratio of pre-compression modifier / formaldehyde is 0.001~0.02:1, the mass ratio of the first batch of urea / formaldehyde is 0.70~1.20:1, the mass ratio of the first batch of melamine / formaldehyde is 0.02 ~0.14:1, in order to adjust the pH value to 7.0~9.0, raise the temperature to 80~95℃, react for 30~50min; the second step: adjust the pH to 4.0~6.5, react at 80~95℃, control the reaction at 30min~120min To cloud point

[0019] The third step: add the second batch of urea, the second batch of melamine and the second batch of straw ethanol by-products, where the mass ratio of the second batch of urea /

[0023] Example 1

[0024] Step 1: Add 250g of 36.8wt.% formaldehyde solution, 37.8g of water, 0.1g of polyvinyl alcohol 2699, 102.7g of the first batch of urea, 2g of the first batch of melamine, and 10g of the first batch of straw ethanol into a 500mL four-necked flask. product. Start the stirring and adjust the pH value to 7.0 with 30wt.% NaOH solution, raise the temperature to 80°C, and react for 30min;

[0025] Step 2: Use 20wt.% NH 4 Adjust the pH of the Cl solution to 4.0 and react at 85°C for 30 min to the cloud point;

[0026] The third step: add the second batch of urea 34.5g, the second batch of melamine 2g, and the second batch of straw ethanol by-product 10g, adjust the pH to 6.0 with 30wt.% NaOH solution, and react at 90°C for 30 minutes;

[0027] The fourth step: add the third batch of 12 g of melamine and 10 g of straw ethanol by-product, adjust the pH value to 7.1 with a 30 wt.% NaOH solution, and react at 90° C. for 30 min.

[0028] Step 5: Cool down to 70°C, add 34g of

[0030] Example 2

[0031] Step 1: Add 250g of 36.8wt.% formaldehyde solution, 50.8g of water, 0.7g of polyvinyl alcohol 1799, 90g of the first batch of urea, 4g of the first batch of melamine and 15g of the first batch of straw ethanol into a 500mL four-necked flask . Start stirring and adjust the pH value to 7.5 with 30wt.% NaOH solution, heat up to 85°C, and react for 40 minutes;

[0032] Step 2: Use 20wt.% NH 4 Adjust the pH of the Cl solution to 4.5, and react at 90°C for 80 min to the cloud point;

[0033] The third step: add the second batch of urea 27.5g, the second batch of melamine 4g, and the second batch of straw ethanol by-product 15g, react at 90°C for 30 minutes, and adjust the pH to 6.5 with 30wt.% NaOH solution;

[0034] The fourth step: adding 24 g of the third batch of melamine and 15 g of straw ethanol by-product, adjusting the pH to 7.5 with a 30 wt.% NaOH solution, and reacting at 85° C. for 40 min.

[0035] Step 5: Cool down to 70°C, add 27.5g of the third batch of