Synthesis and formulation of the hottest polyvinyl

Synthesis and formula examples of polyvinyl acetate lotion adhesive (Part 2)

(4) operation method of polyvinyl acetate lotion synthesis preparation polyvinyl acetate lotion can be synthesized by chemical method and short irradiation method. The particle size of lotion prepared by irradiation method is uneven and requires high equipment, so this method is generally not used. Only chemical method is introduced here. There are two ways of chemical method: intermittent operation and continuous operation. The specific process methods are introduced below

① continuous lotion polymerization method

a, put the measured deionized water and polyvinyl alcohol (PVA) into the dissolution kettle, put steam into the jacket of the dissolution kettle, raise the temperature to 80~85 ℃, stir and dissolve for 4~6h, so that PVA is completely dissolved, and prepare a 10% (mass) PVA solution

b. Filter the prepared 10% (mass) PVA solution and put it into the polymerization kettle together with OP-10 in these product combinations. Start stirring to make it fully mixed, then put vinyl acetate (about 1/7 of the total amount) and 10% (mass) potassium persulfate solution (about 2/5 of the total amount) in the metering tank into the polymerization kettle respectively, stir and emulsify for 30min, because the addition of toughening agent improves the shrinkage of the material

c, put steam into the jacket of polymerization kettle, raise the temperature of materials in the kettle to 60~65 ℃, and stop heating. At this time, the polymerization reaction starts, because it is an exothermic reaction, and the temperature in the kettle will automatically rise to 75~85 ℃. At this time, the reflux condenser will have reflux. When the reflux decreases, start dropping vinyl acetate into the polymerization kettle through the metering tank, and drop potassium persulfate melt through the metering tank [add 4% to 5% of potassium persulfate per hour (mass)]. Control the dropping speed to keep the polymerization temperature at 78~80 ℃, and the dropping is completed in about 8h

d. After the monomer is added, add all the remaining potassium persulfate solution to terminate the reaction chain. After all materials are added, the temperature will automatically rise to 90~95 ℃, and the temperature will be kept for 30min

e. cool the product to 50 ℃ with cold water in the jacket of the polymerization kettle, add the specified amount of sodium bicarbonate solution and DBP and other additives through the metering tank, mix them well, and then discharge the material after filtration

⑦ intermittent lotion polymerization method

a, add PVA and water to the dissolution kettle, raise the temperature to 80~85 ℃. Stir and dissolve for 2h, and prepare a 10% (mass) PVA solution

b. Filter the PVA aqueous solution and put it into the polymerization kettle. Add OP-10 and vinyl acetate (about 14% (mass) of the total monomer) and 10% (mass) of ammonium persulfate aqueous solution [the total amount is 40% (mass) of the product of bacteria when the growth conditions are unbalanced]. Close the feeding hole and open the cooling water. Raise the temperature to about 65 ℃ within 30mm. When droplets appear in the mirror, stop heating, and the temperature can automatically rise to 75-85 ℃

c. When the reflux is normal, begin to add vinegar. Those new sustainable materials that help ultralight aircraft complete tasks will be widely used in ordinary supplies (about 8-9h dripping). Add 4% to 5% ammonium persulfate per hour, and control the uniform polymerization by adjusting its adding speed. The reaction temperature is controlled at 75-80 ℃, which can be adjusted by the amount of monomer added

d. After the monomer is added, add the remaining ammonium persulfate, and the liquid temperature will automatically rise to 90~95 ℃, holding for 30min. Cool to below 50 ℃, and add 10% sodium bicarbonate solution by mass

2 formula example of polyvinyl acetate lotion adhesive

[formula] 1 component mass component mass component polyvinyl acetate 100 polyvinyl alcohol 17885.4op-101.1 dibutyl phthalate 10.9 potassium persulfate 0.2 sodium bicarbonate 0.3 deionized water 100 purpose synthetic polyvinyl acetate lotion. It can be used for wood, paper, packaging and construction. [Formula] 2 components, mass components, mass components, vinyl acetate 355 polyvinyl alcohol 178831.5op-104 ammonium persulfate 0.72 sodium bicarbonate 1.1 dibutyl phthalate 4 water 318 uses to synthesize polyvinyl acetate lotion. It can be used for wood, paper, packaging and construction. [Formula] 3 components, mass components, mass components, polyvinyl acetate lotion 40~100 cement, 100 fine sand, 100 calcium chloride, 1 water. Suitable for concrete bonding and wharf repair. [Formula] 4 components, mass components, mass components, vinyl acetate 50, polyvinyl alcohol 1788 and 17998op-100.6 ammonium persulfate 0.1, appropriate amount of sodium bicarbonate