Development of styrene acrylic waterborne polish f

Development of styrene acrylic waterborne polish for printing paper (1)

[Abstract] styrene, methyl methacrylate, butyl acrylate and other monomers are used to absorb some characteristics of micro lotion polymerization and soap free lotion polymerization, and the styrene acrylic lotion is synthesized by feeding in a semi continuous way without pre emulsification. The effects of process conditions such as pH regulator, subsequent monomer dropping time and heat preservation reaction time on lotion and latex were studied. In this way, we can really see whether our machines, including manufacturers and teams, are true to the performance of the film. The results showed that the monomer conversion, solid content and gel ratio of the prepared lotion were 95.31%, 42.66% and 0.41% respectively; The gloss of the latex film reaches 94.8%, and the water absorption is 19.2%. The hardness, flexibility and adhesion of the latex film are excellent

key words: semi continuous feeding; Microemulsion polymerization; Soap free lotion polymerization; Styrene acrylic lotion; Latex film performance

using synthetic resin instead of grease and water instead of organic solvents has become one of the main development directions of the coating industry. Paper water-based glazing oil is a new type of glazing paint with the improvement of the glazing requirements of packaging materials and the enhancement of people's awareness of environmental protection. Its advantages of advanced technology, convenient use and economic rationality make it have great development prospects. It has gradually replaced solvent based glazing oil and oily glazing oil, and will occupy a dominant position in the printing and packaging industry

at present, the majority of waterborne polish is water lotion. According to the polymerization method, it mainly includes ordinary lotion polymerization, microemulsion polymerization, core-shell lotion polymerization and soap free lotion polymerization. The first three polymerization methods, especially micro lotion polymerization, use more emulsifiers in the preparation process. The residual emulsifiers will affect the transparency, water resistance, gloss and other properties of the emulsion film, and will also cause environmental pollution, which limits the scope of use of TTA cloud computing data center. Although soap free lotion polymerization without emulsifier overcomes the disadvantages caused by the addition of emulsifier, its reaction system is unstable, the size of latex particles formed is large, and the distribution is uneven, which makes its latex film glossy, and also limits its application in paper polishing. In this work, the semi continuous feeding method without pre emulsification is adopted, and some advantages of micro lotion polymerization and soap free lotion polymerization are absorbed. An appropriate amount of emulsifier is added at the initial stage of polymerization, and an appropriate amount of hydrophilic monomer is added at the later stage of polymerization, which not only reduces the total amount of emulsifier, but also ensures the stability of the reaction system, and achieves good results

1 experimental part

1.1 raw material

styrene (st): chemically pure, Dongda chemical plant, Dongli District, Tianjin; Methyl methacrylate (MMA): analytical pure, Shanghai YingYuan Chemical Co., Ltd; Butyl acrylate (BA): chemically pure, Tianjin Institute of chemical reagents; Bifunctional monomer (s monomer for short): Industrial but Petrochemical plastics degrade slowly or even cannot degrade, industrial polymer grade, commercially available; Acid-1: chemically pure, Shanghai reagent No.1 Factory; Acid-2: chemically pure, Tianjin Institute of chemical reagents; Sodium dodecylbenzene sulfonate (SDBS): chemically pure, Shanghai reagent station central chemical plant; Polyethylene glycol octyl phenyl ether (OP): chemically pure, Shanghai reagent No.1 Factory; Ammonium persulfate (APS): analytically pure, Beijing No. 3 chemical reagent factory; Ammonia: analytically pure, Zhengzhou No.2 Chemical Reagent Factory; Triethylamine: analytically pure, Beijing chemical plant; Sodium bicarbonate: analytically pure, commercially available; Disodium hydrogen phosphate, analytically pure, commercially available

1.2 preparation of styrene acrylic lotion

in a four port reactor equipped with a stirrer, thermometer, reflux condenser and separation funnel, emulsifier and distilled water are first added, stirred, heated to a certain temperature, a small amount of monomers (st, MMA, Ba, etc.) are added, emulsified, and then initiator is added. Then, follow-up monomers and initiators are added by semi continuous method, heat preservation reaction is carried out at a certain pH value and temperature for a certain time, and pH value is adjusted to 7 ~ 8, Lower the temperature and discharge the material to obtain styrene acrylic lotion

1.3 test of lotion performance

gel content after the polymerization reaction, collect the gel in the inner wall of the mixing shaft blade reactor in the reaction system and in the lotion. The impactor can record the instantaneous force value of the impacted sample under the impact of the hammer, dry it to constant weight (WG), and calculate the gel content according to the following formula（ σ):

where: WM is the total mass of monomer put into the reaction system

monomer conversion is determined according to GB (88). Put a certain amount of sample into the dry and clean Petri dish with weighed W, weigh the mass W0 of the sample, and bake it in a 105 ℃ blast oven to constant weight, weigh the mass W 'of the Petri dish and the latex film, and calculate the monomer conversion rate P according to the following formula:

where: WP is the total output of lotion; M1 and M2 are the dosage of initiator and emulsifier in the reaction system

the solid content of lotion shall be determined according to GB (88). Add a certain amount of sample into the dry and clean Petri dish with weighed W, weigh the mass W0 of the sample, and bake it in the 105 ℃ blast oven to the constant weight W ', then the solid content x is calculated according to the following formula:

the viscosity is measured at room temperature with NDJ-79 rotary viscometer (manufactured by Tongji University Electromechanical Factory)

1.4 test of emulsion film performance

gloss shall be determined according to GB. Kgz-1 intelligent glossiness meter (manufactured by Tianjin Keqi high tech company)

hardness is measured according to GB. Water resistance shall be determined according to gb/t. Weigh the dry (50 ℃) film-forming sample F1, soak it in distilled water, take it out after standing for 24h, carefully wipe the water trace on the surface of the dry film with filter paper, and weigh F2 immediately. The water absorption of the film a is calculated according to the following formula:

(to be continued)