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The divinyl silane modified self-crosslinking polyacrylate latex was successfully prepared by semicontinuous seeded emulsion polymerization. Methyl methacrylate (MMA) and butyl acrylate (BA) were used as main monomers and the reaction was initiated by potassium persulfate (KPS). The modified monomer 1, 3-divinyltetramethyldisiloxane (DVMS) and crosslinked monomer hydroxyethyl acrylate (HEA) were introduced into the basic dispersion. Sodium dodecyl sulfonate (SDS) anionic surfactant and alkyl polyglycoside (APG) nonionic emulsifier were utilized as composite emulsifiers. The structure of latex film was characterized by Fourier transform infrared spectroscopy (FTIR). The latex films were tested by thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and contact angle (CA) and apparent crosslinking percentage. The particle size of the emulsion was measured by Zetatrac dynamic light scattering instrument. The optimum conditions are as follows: the amount of composite emulsifier is 5.0%, the mass ratio of SDS to APG is 1:1, the amount of initiator is 0.5%, the amount of DVMS is 5.0%, and the amount of HEA is 1.0%. The emulsion has good mechanical stability and chemical stability, and the storage stability is ideal. The dispersion is blue and translucent, with a small particle size. The apparent crosslinking percentage of the latex film is above 89%, and the highest contact angle was more than 98°. The polyacrylate colloidal film prepared in this paper has outstanding thermal stability and hydrophobicity. [ABSTRACT FROM AUTHOR]

Purpose: Fluorine materials have received the keen attention of many researchers because of their water repellency and low surface free energy. The purpose of this paper is to prepare fluorine-containing soap-free acrylic emulsion, which sodium allyoxypropyl hydroxypropyl sulfonate (COPS-1) and anionic emulsifier sodium a-alkenyl sulfonate (a-AOS) were combined as polymerizable emulsifier, and undecylenic acid (UA) and dodecafluoroheptyl methacrylate(DFMA) were introduced as functional monomer. Design/methodology/approach: The fluorinated polyacrylate emulsion was successfully prepared by semi-continuous seed emulsion polymerization, wherein the main monomers were methyl methacrylate (MMA) and butyl methacrylate (BA), and the initiator was potassium persulfate (KPS). Sodium alloxypropyl sulfonate (COPS-1) and an anionic emulsifier sodium a-alkenyl sulfonate (a-AOS) were compounded as a polymerizable emulsifier. Besides, undecylenic acid (UA) and dodecafluoroheptyl methacrylate (DFMA) were introduced as the functional monomers. Findings: The optimum recipe of preparing the modified latex is as follows: the amount of emulsifier was 4%, the ratio of emulsifier (COPS-1: AOS) was 3: 1, and the content of initiator was 0.6%. In this case, the conversion rate of acrylic polymer emulsion was high and the polymerization stability was good. When the amount of monomer UA was 2% and the amount of DFMA was 4%, the overall performance of the emulsion was the best. Originality/value: The fluorine-containing soap-free acrylic emulsion is prepared via semi-continuous seeded emulsion polymerisation, which sodium allyoxypropyl hydroxypropyl sulfonate (COPS-1) and anionic emulsifier sodium a-alkenyl sulfonate (a-AOS) were combined as polymerizable emulsifier, and undecylenic acid (UA) and dodecafluoroheptyl methacrylate (DFMA) were introduced as functional monomer. There are two main innovations. One is that the fluorine-containing soap-free acrylic emulsion is prepared successfully. The other is that the undecylenic acid is introduced as functional monomer. [ABSTRACT FROM AUTHOR]

The novel cross-linking (butyl acrylate- co-isobornyl methacrylate) colloids are prepared via semi-continuous seeded emulsion polymerization of butyl acrylate, isobornyl methacrylate and N-methylol acrylamide in aqueous phase using mixture of polyethylene glycol mono(octylphenyl) ether and sodium dodecyl sulphate as emulsifier and potassium persulphate as initiator. The optimal composition for preparing the novel cross-linking colloid was determined, and the structure of the as-prepared colloid was confirmed with FTIR spectrum. The formation of colloidal polymer was also corroborated by a difference between glass transition temperatures of colloid film and corresponding homopolymers. Calorimetry measurements showed that the colloid is composed of random copolymer. The particle size distribution exhibits unimodal character, suggesting a high stability of the colloid polymer. [ABSTRACT FROM AUTHOR]

Nonylphenol ethoxylates (NPEOs) are widely used as surfactants for emulsion polymerization and for post adding stabilization for latex applications in formulations with high filler content. However, NPEOs are bioaccumulative and persistent in the environment while nonylphenol, the breakdown product of NPEs, is an endrocrine disruptor. Therefore, it has been recommended to ban technical processes using NPEOs as surfactants. The acrylic polymer latex was prepared via semi-continuous seeded emulsion polymerization of butyl acrylate and methyl methacrylate in water phase initiated with potassium persulfate when nonylphenol ethoxylates are replaced with alkyl polyglycoside (APG) surfactants. The structure of the resultant acrylic polymer latex is confirmed with Fourier transform infrared spectroscopy spectrum. Differential scanning calorimetry confirms that the resultant latex is a kind of random copolymer and the consistency among the chain segment is fairly good. Influences of amount of APG on the properties of the resultant latex and its film were investigated. Results show that the particle size of the latex is decreased with the increase of the amount of APG. And the ionic stability of latex is also improved with the increase of the amount of APG. However, the water-resistance of the film of the latex is decreased with the increase of the amount of APG. [ABSTRACT FROM AUTHOR]

BA-MMA-POMA copolymer latex was successfully prepared by soap-free emulsion polymerization of 2-(perfluoro-(1,1-bisisopropyl)-2-propenyl)oxyethyl methacrylate(POMA) with butyl acrylate(BA), methyl methacrylate (MMA) initiated by K [ABSTRACT FROM AUTHOR]

Water-based architectural heat insulation coating was studied to overcome the drawbacks of conventional inorganic silicate heat insulation coating. The heat insulation coatings were prepared with the method of mechanical agitation when the technology of emulsion blending was adopted, and the mixed organic polymer emulsions were used as binder of the coatings and the mixed heat insulating aggregates were applied as powder, and nanoscaled SiO2 and TiO2 were introduced, and some assistants were also added. Results showed that the prepared coating had excellent physical-chemical properties. The test of the authoritative inspection organization shows that coefficient of heat conductivity is 0.073 W/mK, which is lower by far than that of conventional heat-insulating materials. The time of artificial weathering is more than 1000 hours. Water temperature difference in the plastic container, which was coated with heat insulation coatings, represented the heat-insulating property of the coatings. The influences of components of mixed polymer emulsion, mass ratio of polymer emulsion to powder, component of heat insulating aggregates, particle size of heat insulating aggregates, nanoscaled SiO2 and TiO2 on the properties of the coatings were studied. [ABSTRACT FROM AUTHOR]

The acrylate emulsion was prepared via pre-emulsified and semicontinuous seeded emulsion polymerization technology when nonreactive emulsifiers such as sodium dodecyl-benzenesulfonate (DSB) are replaced with reactive emulsifiers such as sodium2-hydroxy-3-(methacryloyloxy)propane-1-sulfonate (HPMAS). Influence of HPMAS on the particle size, water resistance, viscosity, rheology, and stability of the emulsion was studied. Results show that the particle size and the viscosity of the emulsion are increased with the added amount of HPMAS. However, water resistance of film first is increased and then decreased with the increase of the added amount of HPMAS. The water resistance of the film is best when the added amount of HPMAS is 2.0%. The viscosity of the emulsion is increased with the increase of the added amount of HPMAS. Both the mechanical stability and the freezing-thaw stability of the emulsion are improved when DSB is replaced with HPMAS during the course of the emulsion polymerization. The emulsion is of rheological properties of pseudo-plastic fluid and belongs to non-Newtonian fluid. [ABSTRACT FROM AUTHOR]

The new fluorinated acrylate emulsion was synthesized by using the intermediate perfluorous nonene and 2-hydroxyethyl methacrylate as the staring reactants via semi-continuous seeded emulsion polymerization. The structures, glass transition temperature, thermal property and water repellency of the fluorinated acrylate emulsion were characterized with FTIR, differential scanning calorimetry, thermal analysis, and contact angle meter. Influences of many factors such as the theoretical solid content, the temperature of the emulsion polymerization on the stability of the emulsion polymerization, the added amount of emulsifiers and the added amount of the initiator were studied. Results show that the stability of the emulsion polymerization is fairly good when the theoretical solid content is below 30% and the reaction temperature is 80°C and the added amount of emulsifiers and the initiator are 6.0-8.0% and 2.0% respectively. In comparison with the acylate emulsion, the thermal stability of the fluorinated acrylate emulsion is decreased but the water repellency of the fluorinated acrylate emulsion is greatly increased. [ABSTRACT FROM AUTHOR]