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Polymer flooding has a significant potential to enhance oil recovery in a light oil reservoir. However, for polymer flooding in a conventional heavy oil reservoir, due to unfavorable mobility ratio between water and oil, the improvement of sweep efficiency is limited, resulting in a low incremental oil recovery and failure to achieve high-efficiency development for polymer flooding in a conventional heavy oil reservoir. Inspired by the EOR mechanisms of the surfactant-polymer (SP) flooding process, the polymer-viscosity reducing surfactant flooding (P-VRSF) system was proposed to enhance conventional heavy oil recovery. Thus, to gain an insight into enhancing oil recovery by P-VRSF in a conventional heavy oil reservoir, the viscosity property, oil-water interfacial tension property, and oil viscosity reduction property were investigated. A series of parallel sand pack experiments were conducted to investigate enhanced oil recovery ability of polymer flooding and P-VRSF in a heterogeneous reservoir. Then, the 2D micromodel flooding experiments were conducted to investigate the EOR mechanism from porous media to pore level. Results demonstrated that polymer could increase the viscosity of injection water and improve the sweep efficiency. The emulsifying stability of surfactant with ultralow IFT (10-3 mN/m) was worse than that of the surfactant with higher IFT (10-2 mN/m). The viscosity reduction rate of the surfactant with higher IFT was higher than 80% at different oil-water volume ratios. The incremental oi recovery of P-VRSF was higher than that of polymer flooding. Moreover, the polymer-viscosity reducing surfactant with higher IFT could have higher incremental oil recovery. The 2D micromodel flooding results showed that the swept area of polymer flooding and P-VRSF was larger than that of water flooding. Moreover, the swept area of the surfactant with good emulsifying stability was larger than that of the surfactant with ultralow IFT. These findings could provide insights into enhancing oil recovery by P-VRSF in the conventional heavy oil reservoir. [ABSTRACT FROM AUTHOR]

The novel vinyl acetate (VAc)/vinyl neo-decanoate (VeoVa10)/dibutyl maleate/triethoxy vinyl silane quadripolymer latex was prepared via the semi-continuous seeded emulsion polymerization emulsified with disodium laureth sulfosuccinate (AEMES) as anionic surfactant and beta-cyclodextrin (β-CD) mixture as emulsifier and initiated with potassium persulfate (KPS), respectively. The chemical compositions of copolymer was determined by Fourier transform infrared spectromer (FTIR). The glass transition temperature (T g) of the copolymer was measured by differential scanning calorimetry. The water resistance of the film was assessed by the water contact angle measurement. The conditions of preparing the novel latex were optimized and obtained as follows. The amount of AEMES and β-CD mixtures were 6 wt% and the mass ratio of AEMES to β-CD were 1:1. The dosage of KPS was 0.6 wt% and the mass ratio of VAc to VeoVa10 was 3:1. The amount of dibutyl maleate and triethoxy vinyl silane was 4% and 3%, respectively. In this case, the conversion percentage of the mixed monomers was 99.0% and the polymerization stability was good. [ABSTRACT FROM AUTHOR]

The novel fluoro-silicone polyacrylate latex was successfully synthesized in the presence of a novel green mixed emulsifier of β -cyclodextrin (β -CD) and sodium lauroyl glutamate (SLG) by semi-continuous seeded emulsion polymerization, which was initiated with potassium persulphate. Methyl methacrylate (MMA) and butyl acrylate (BA) were used as the main monomers, while hexafluorobutyl methacrylate (HFMA) and vinyltriethoxysilane (VTES) were used as the functional monomers. The resultant latex and its film were characterized by Fourier transform infrared spectroscopy, thermogravimetric analysis, differential scanning calorimetry and contact angle determinator, respectively. The optimum conditions of preparing the fluoro-silicone polyacrylate latex are as follows: the amount of compound emulsifiers are 7.0%; β -CD: SLG = 1:2; the amount of initiator is 0.7%; the appropriate proportion of main monomer of MMA: BA = 1:1; and the amounts of HFMA and VTES are 6.0% and 4.0%, respectively. In this case, the resultant latex has high conversion rate, low gel rate and good stability. Results showed that both thermal stability and hydrophobic property of the latex are improved with the incorporation of a small amount of HFMA and VTES. [ABSTRACT FROM AUTHOR]

Abstract: The novel modified acrylate colloid was synthesized by semi‐continuous seeded emulsion polymerization which was initiated with potassium persulfate (KPS), and octylphenol polyoxyethylene ether (OP‐10) and sodium dodecyl benzene sulfonate (SDBS) were used as surfactants. Butyl acrylate (BA) and methyl methacrylate (MMA) were used as the main monomers and hexafluorobutyl methacrylate (HFMA, C8H8F6O2), and benzyl methacrylate (BZMA, C11H12O2) were used as functional monomers. Factors such as the amount of initiator, mass ratio of SDBD to OP‐10 and monomers, which have an influence on particle size and morphology of the resultant colloid, are studied. Chemical composition of the modified acrylate colloid was evaluated by Fourier transform infrared spectrometry (FTIR). The thermal performances were characterized by differential scanning calorimetry (DSC) and thermogravimetry (TG). Furthermore, surface hydrophobicity of the latex film was examined by measurement of water absorption and water contact angle. Results indicate that the modified acrylate colloid has highest monomer conversion rate and lowest coagulation percentage when the mass fraction of emulsifier was 4% and mass ratio of SDBS to OP‐10 was 1:2, mass fraction of initiator was 0.3%, mass percent of HFMA was 6%, and the amount of BZMA was 2%. Benzene ring‐containing monomer is effectively participated in the reaction and has improved the thermal performance and surface properties of copolymer colloid. The resultant colloid has excellent hydrophobicity and low surface energy. Solid content of the resultant colloid was about 30% (wt %). [ABSTRACT FROM AUTHOR]

Purpose Motivated by the globally increasing concern over environmental protection, the interest of a large part of the scientific community focuses on the development of green surfactants aiming to replace traditional toxic surfactants-based alternatives. The purpose of this paper is to prepare acrylate copolymer latex modified with fluorine and silicone monomer, which is emulsified with the green surfactants of sodium rosinate and alkyl polyglycoside (APG).Design/methodology/approach A series of acrylic copolymer latexes containing fluorine–silicon have been prepared by semi-continuous seed emulsion polymerisation of mixed monomers of methyl methacrylate (MMA), butyl acrylate (BA), hexafluorobutylmethacrylate (HFMA) and vinyltriethoxysilane (VTES) and emulsified by green mixed surfactants of sodium rosinate and APG.Findings The optimum recipe of preparing the emulsion is as follows: the amount of emulsifiers is 6 per cent and the mass ratio of sodium rosinate to APG is 1:3. The amount of initiator is 0.4 per cent, and the amounts of the silicon monomer and fluorine monomer are 5 and 7 per cent, respectively. In comparison with the acrylate latex prepared without fluorine monomer and silicon monomer, the thermal stability and the water resistance of the film of the resultant latex clearly improved.Practical implications The acrylic copolymer latexes containing fluorine–silicon emulsified with green surfactants can be used in the coatings, adhesives, finishing agents and so on.Originality/value The acrylic copolymer latexes containing fluorine–silicon have been prepared by semi-continuous seed emulsion polymerisation. The green mixed surfactants of sodium rosinate and APG have been used as the emulsifiers to replace traditional toxic surfactants-based alternatives. [ABSTRACT FROM AUTHOR]

Fluoro-silicone modified polyacrylate latex was successfully prepared by semi-continuous seeded emulsion polymerization in the presence of a green mixed emulsifier consisting of cashew phenol polyoxyethylene ether sulfonate (BCE-10B) anionic surfactant and alkyl polyglycoside (APG) nonionic surfactant, in which the mixed monomers were initiated with potassium persulfate (KPS). The structure and properties were characterized by Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and contact angle (CA), respectively. Results show that the optimal conditions of synthesizing the novel emulsion are as follows: the total concentration of mixed emulsifiers is 5.0%; the optimum mass ratio of APG to BCE-10B is 2:1; the amount of initiator is 0.6%; the composition of main monomers of MMA:BA = 1:1; and the concentrations of HFMA and VTES are 4.0 and 6%, respectively. In this case, the resultant emulsion showed good thermal stability and hydrophobicity. [ABSTRACT FROM AUTHOR]

The fluorinated polyacrylate latex were successfully prepared with semi- continuous seeded emulsion polymerization of butyl acrylate (BA), methyl methacrylate (MMA) and hexafluorobutyl methacrylate (HFMA) which was initiated with potassium persulfate (KPS) initiator and emulsified with the novel mixed surfactants of sodium lauryl glutamate (SLG) and alkylphenol ethoxylates (OP-10). The structure of the resultant latex was confirmed by Fourier transform infrared spectroscopy (FTIR). The particle size of the latex was measured by Zetatrac dynamic light scattering detector. The film of latex was tested by differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and contact angle (CA). The optimum conditions of preparing the novel fluorinated polyacrylate latex are optimized and the results are as follows: the amount of emulsifiers is 4.0%; mass ratio of SLG to OP-10 is 1:1, the amount of the initiator is 0.6%. The mass ratio of MMA to BA is 1:1 and the amount of HFMA is 7.0%. In this case, the conversion is high and the polymerization stability is good. In addition, the water resistance and thermal properties of the latex films were improved significantly in comparison with the film of the latex prepared without the fluorinated monomer. [ABSTRACT FROM AUTHOR]

Purpose At present, the conventional method of preparing cationic fluorinated acrylic latex is to emulsify copolymerised monomers with cationic surfactants. However, there has been a wide concern about using Gemini surfactants to prepare cationic polymer latex to improve its properties. The purpose of this paper was to focus on the synthesis of novel self-crosslinked cationic fluorinated acrylic latex (SCFAL), during which the copolymerised monomers were initiated with a water soluble azo initiator and emulsified with mixed surfactants of Gemini emulsifier and alkyl polyglycoside (APG).Design/methodology/approach The novel SCFAL was prepared successfully by the semi-continuous seeded emulsion polymerisation of butyl acrylate, methyl methacrylate, hexafluorobutyl methacrylate (HFMA) and hydroxy propyl methacrylate (HPMA) in aqueous medium.Findings The conversion is the maximum and the coagulation percentage the minimum when the amounts of emulsifier and initiator are 8 and 0.6 per cent, respectively. The average particle size of the latex is significantly reduced with the increase of the amount of emulsifiers used. However, the average particle size of the latex is increased with the increase of the amount of HPMA. The particle size of the latex is of a unimodal distribution, which means that the particle size was reasonably uniform. Contact angle is increased with the increase of the amount of the HFMA.Practical implications The novel SCFAL can be widely used as significant components in the field of coatings, leather, textile, paper, adhesives and so on.Originality/value SCFAL, which was emulsified with novel mixed surfactants of Gemini surfactant and APG, has been prepared successfully. Influences of amount of initiator, emulsifier, HPMA and HFMA on emulsion polymerisation and/or properties of novel latex are investigated in detail. [ABSTRACT FROM AUTHOR]

The novel cationic polyacrylate latex containing fluorine silicon was successfully prepared via soap-free emulsion polymerization of butyl acrylate, methyl methacrylate, vinyltriethoxysilane and hexafluorobutylmethacrylate in water phase, which were initiated with water soluble azo initiator and emulsified with the mixed surfactants polymerizable emulsifier and OP-10. The films of the resultant latex were characterized by Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and contact angle (CA) determinator, respectively. In comparison with the conventional polyacrylate latex, the thermal stability and water resistance of novel latex film are improved. The conditions of preparing the novel cationic acrylate latexes were optimized. The optimum conditions of preparing the novel latex are as follows: the amount of emulsifiers and the initiator are 6.0% and0.3%, respectively; both the amount of VETS and amount of HFMA are 6.0%. In this case, the conversion is high and the polymerization stability is good. [ABSTRACT FROM PUBLISHER]

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]

The nanometre fluorinated acrylate latex was prepared via semi-continuous seeded emulsion polymerisation of butyl acrylate, methyl methacrylate and hexafluorobutyl acrylate in water phase when gemini surfactant and 2,2′-azobis[2-(2-imidazolin-2-yl)propane] dihydrochloride are used to be emulsifier and initiator, respectively. The resultant latex is characterised by Fourier transform infrared (FTIR) spectrometry, contact angle measurements, dynamic light scattering and differential scanning calorimetry (DSC). FTIR spectrum identifies the formation of terpolymer. DSC confirms that the latex is a kind of random terpolymer and the consistency among the chain segment is fairly good. The average particle size of latex is decreased with the increase of the amount of gemini surfactant. The particle size of resultant latex is 22.4 nm and is further confirmed by transmission electron microscope when the amount of gemini surfactant is 3%. However, the viscosity of latex is increased with the increase of the amount of gemini surfactant. In comparison with the nanometre fluorinated acrylate latex, the hydrophobic property of the resultant latex is improved. [ABSTRACT FROM AUTHOR]

Abstract: The novel fluorinated anionic surfactant sodium p-perfluorononenyloxy benzene sulfonate (SPBS) was successfully prepared by sulfonation of p-perfluorononenyl phenyl ether (PPE). PPE was synthesized from the intermediate perfluoro nonene and phenol as the staring reactants. The structure of SPBS was investigated by Fourier transform infrared (FTIR) spectrometry and nuclear magnetic resonance (NMR). The reaction conditions of preparing PPE and SPBS are optimized, respectively. The combined properties of SPBS are studied. The optimum reaction conditions of preparing PPE and SPBS are as follows: (a) synthesizing PPE: reaction temperature is 65; and the mole ratio of perfluoro nonene to triethylamine is 1:0.50; and the mole ratio of perfluoro nonene to phenol is 1:1.3; and the reaction time is 3.5h; (b) synthesizing SPBS: the mole ratio of PPE to sulfur trioxide is 1:1.20; and the sulfonating time is 60min. Results show that SPBS has excellent surface activity and combined properties. [Copyright &y& Elsevier]

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]