一种富马酸类可聚合乳化剂的合成及其乳液性能研究

马来酸酐和十四醇在80℃酯化反应1 h得马来酸单十四酯;然后和PCl3在60℃反应2 h得单十四酯马来酰氯;最后与N-甲基牛磺酸钠在70℃反应1 h得白色粉末状固体,用w(CH3CH2OH)=95%的乙醇重结晶,得到一种富马酸类磺酸盐阴离子可聚合乳化剂——N-甲基-N-十四醇单酯马来酰基-牛磺酸钠。用质谱和1HNMR鉴定了目标化合物,结构正确。将所合成的可聚合乳化剂用于醋酸乙烯酯-丙烯酸丁酯-叔碳酸乙烯酯-甲基丙烯酸六氟丁酯乳液聚合,单体转化率97.75%,凝胶率0.02%,乳液固体份质量分数43.52%,乳液多分散性系数(PDI)0.02,呈单分散性。作为对比,非可聚合阴离子乳化剂十二烷基硫酸钠(SDS)同样应用到该乳液聚合体系中,结果发现:由可聚合乳化剂制得的乳液,在耐电解质性能和贮存稳定性方面有所提高,在成膜耐水性方面,可聚合乳化剂制得的乳胶膜浸入水中30 d后,吸水率为13.70%,SDS的吸水率是103.09%,是前者的7.52倍,可聚合乳化剂很好地提高了乳液成膜后的耐水性。     

Concentrated emulsion copolymerization of butyl acrylate and vinyl acetate initiated by a redox initiator at lower temperature

The concentrated emulsion copolymerization of butyl acrylate and vinyl acetate with an ammonium persulfate/sodium hydrogen sulfate mixture as a redox initiator, with a sodium dodecyl sulfate/cetyl alcohol mixture as a compound surfactant, and with poly(vinyl alcohol) as a liquid film reinforcer was carried out at lower temperature. In less than 3 h, the polymerization conversion was greater than 95%. The effects of the surfactant, the initiator, the volume fraction of the monomer, and the temperature on the stability of the concentrated emulsion, the kinetic process, and the average size of the latices were examined. The morphology of the polymer particles was observed by transmission electron microscopy, and the average size and distribution of the particle diameter were measured by photon correlation spectroscopy. The kinetic equation was R_p = k[M]^0.38[I]^0.89[E]^?0.80 at 30°C (where R_p is the polymerization rate, [I] is the initiator concentration, [M] is the monomer concentration, and [E] is the concentration of the compound surfactant), and the apparent activation energy was 22.69 kJ/mol. The thin‐layer polymerization of the concentrated emulsions, which enabled the removal of the heat of polymerization, was performed first. In comparison with test‐tube polymerization, thin‐layer polymerization provided a more regular morphology of the polymer particles. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 570–576, 2004     

Novel Maleate Surfmer for Stabilization High-solid Content of Methyl Methacrylate/Butyl Acrylate Copolymer Emulsion System

A novel polymerizable surfactant (surfmer) based on nonyl phenol ethoxylate backbone and maleic anhydride was synthesized. The chemical structure of the surfmer was characterized by ¹³C, ¹H nuclear magnetic resonance, and surface tension analyses. The surfmer was used in emulsion system of methyl methacrylate/butyl acrylate copolymer at different concentrations to explore its stabilization efficiency using seed emulsion polymerization technique. The result of thermogravimetric analysis showed that the incorporation of the surfmer retarded the decomposing of the polymer chain. The stability of the emulsion was enhanced by adding the surfmer, but the glass transition of the film was decreased dramatically.     

Kinetics of the emulsion copolymerization of MMA/BA in the presence of sodium montmorillonite

The kinetics of the emulsion copolymerization of methyl methacrylate/butyl acrylate (MMA/BA = 50/50) in the presence of sodium montmorillonite (Na-MMT) was investigated. Sodium laurylsulfate was used as surfactant at different concentrations and potassium persulfate as initiator. Two series of experiments were carried out at 30% and 10% solids content and varying the amount of surfactant and sodium montmorillonite. The effect of surfactant and sodium montmorillonite content on the stability of the final latices was assessed. The effect on particle nucleation, polymerization kinetics and molar mass distribution was also discussed, and compared with the predictions of the Smith–Ewart theory.     

The application research of environment-friendly reactive surfactants in acrylate emulsion pressure sensitive adhesives

In this article acrylate pressure sensitive adhesive (PSA) latexes were synthesized via a pre-emulsion seeded semi-batch emulsion polymerization process with a conventional nonreactive surfactant (CO-436) and two polymerizable surfactants (traditional surfmer SE-10N and environment-friendly surfmer SR-10). The effects of surfactant contents on the particle size, zeta potential, electrolyte stability of the latexes and gel content, sol molecular weight (M_w, M_n), water absorption of the PSA copolymers were investigated. In addition, X-ray photoelectron spectroscopy (XPS) and contact angle measurements were used to characterize the latex films. The results showed that the particle sizes of latexes prepared with surfmers were smaller than their CO-436 containing counterparts. And the latexes prepared with surfmers had a lower storage stability than the one prepared with CO-436. However, surfmers can improve the electrolyte stability of the latex. Furthermore, the water resistances of the latexes prepared with surfmers were better than that of the latex with CO-436, which can be confirmed by water absorption, contact angle and XPS analysis. The results also indicated that the PSA prepared with SR-10 exhibited the highest gel content among the three surfactants. Finally, the effects of surfactants on the adhesive properties of the PSAs were also evaluated.     

A New Cationic Gemini Surfmer: Synthesis and Surface Activities

A new cationic gemini surfmer (polymerizable surfactant or surface-active monomer) with an acrylic reactive group in its spacer group was synthesized and characterized, and its surface activity properties were examined in comparison with its intermediate surfactant 12-3OH-12·2Cl⁻, a previously-reported gemini surfmer 12′-2-12′·2Br⁻, as well as monomeric surfactant dodecyl trimethylammonium bromide. It was found that neither the incorporation of a double bond onto the gemini surfactant nor the change of location of the double bond will affect surface activities of the gemini surfactant.     

一种马来酸酯类可聚合乳化剂

以马来酸酐和十二醇聚氧乙烯醚-15(AEO15)为原料,通过一条绿色合成路线,合成了同时具有阴离子和非离子结构特点的马来酸酯类可聚合乳化剂。将可聚合乳化剂与传统乳化剂十二烷基硫酸钠(SDS)分别应用到醋酸乙烯酯-丙烯酸丁酯-叔碳酸乙烯酯-甲基丙烯酸六氟丁酯的半连续式乳液共聚合时发现,由可聚合乳化剂得到的乳胶液电解质稳定性、贮存稳定性及冻融稳定性要优于传统乳化剂,而且使用可聚合乳化剂所成膜的耐水性也得到提高。     

Comparison of styrene reversible addition–fragmentation chain‐transfer polymerization in a miniemulsion system stabilized by ammonlysis poly(styrene‐alt‐maleic anhydride) and sodium dodecyl sulfate

In this study, we conducted the reversible addition–fragmentation chain‐transfer (RAFT) polymerization of styrene (St) in a miniemulsion system stabilized by two different stabilizers, ammonlysis poly(styrene‐alt‐maleic anhydride) (SMA) and sodium dodecyl sulfate (SDS), with identical reaction conditions. The main objective was to compare the polymerization kinetics, living character, latex stability, and particle morphology. The macro‐RAFT agent used in both systems was SMA, which was obtained by RAFT solution polymerization mediated by 1‐phenylethyl phenyldithioacetate. The experimental results show that the St RAFT miniemulsion polymerization stabilized by SDS exhibited a better living character than that stabilized by ammonlysis SMA. The final latices were very stable in two systems, but different stabilizers had an obvious effect on the polymerization kinetics, living character, and particle morphology. All of the particles obtained by RAFT miniemulsion polymerization stabilized by SDS were solid, but an obvious core–shell structure was observed in the miniemulsion system stabilized by ammonlysis SMA. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

Entry in emulsion polymerization using a mixture of sodium polystyrene sulfonate and sodium dodecyl sulfate as the surfactant

A mixture of sodium polystyrene sulfonate (NaPSS) and anionic surfactant, sodium dodecyl sulfate (SDS), was used as the emulsifier in the emulsion polymerization of styrene at 60 °C. The latexes prepared were stable, bearing the better resistance to the addition of electrolyte, and have the larger values in particle size and the higher polymerization rates than those counterparts prepared using SDS only. The NaPSS was prepared by a series of process: a concentrated cyclohexane solution of an anionically polymerized polystyrene (PS) was sulfonated with sulfuric acid at 80 °C, and then neutralized and purified through dialysis. The data of average polymer number per particle (n_p) were found useful in investigating the surfactant content effect on the entry of radicals into particles, where the latex particle size plays an important role.     

High‐molecular‐weight polyurethanes prepared by one‐step miniemulsion polymerization

Through one‐step miniemulsion polymerization, hydrophobic polyurethane (PU) dispersions were prepared, with hexadecane (HD) as costabilizer in the oil phase and sodium dodecyl sulfate (SDS) as surfactant in the water phase. The oil phase, including isophorone diisocyanate, poly(oxytetramethylene) glycol, a costabilizer HD, a chain extender 1,4‐butanediol, a crosslinking agent trimethylol propane, and a catalyst dibutyltin dilaurate (SnDBL), was dispersed in the water phase containing SDS. The influences of experimental parameters, such as SnDBL, NCO/OH equivalents, and concentrations of surfactant, were discussed. The particle size and the molecular weight of PU polymer were measured by light scattering and gel permeation chromatography, respectively. With the addition of SnDBL and higher NCO/OH ratio, PU films with higher molecular weights were produced. The chemical structure of the PU polymer was identified by Fourier transform infrared spectrometer, and the adsorption of urethane group was observed. Thermal gravimetric analysis was used to characterize the thermal stability of PU. Furthermore, mechanical property was also investigated and characterized by tensile strength and elongation at break. With a higher NCO/OH ratio and the existence of SnDBL, the tensile strength of PU films was significantly increased. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2008     

Synergistic Effects between Anionic and Sulfobetaine Surfactants for Stabilization of Foams Tolerant to Crude Oil in Foam Flooding

In foam flooding, foams stabilized by conventional surfactants are usually unstable in contacting with crude oil, which behaves as a strong defoaming agent. In this article, synergistic effects between different surfactants were utilized to improve foam stability against crude oil. Targeted to reservoir conditions of Daqing crude oil field, China (45 °C, salinity of 6778 mg L⁻¹, pH = 8–9), foams stabilized by typical anionic surfactants fatty alcohol polyoxyethylene ether sulfate (AES) and sodium dodecyl sulfate (SDS) show low composite foam index (200–500 L s) and low oil tolerance index (0.1–0.2). However, the foam stability can be significantly improved by mixing the anionic surfactant with a sulfobetaine surfactant, which behaves as a foam stabilizer increasing the half-life of foams, and those with longer alkyl chain behave better. As an example, by mixing AES and SDS with hexadecyl dimethyl hydroxypropyl sulfobetaine (C₁₆HSB) at a molar fraction of 0.2 (referring to total surfactant, not including water), the maximum composite foaming index and oil tolerance index can be increased to 3000/5000 L s and 1.0/4.0, respectively, at a total concentration between 3 and 5 mM. The attractive interaction between the different surfactants in a mixed monolayer as reflected by the negative β^s parameter is responsible for the enhancement of the foam stabilization, which resulted in lower interfacial tensions and therefore negative enter (E), spreading (S), and bridging (B) coefficients of the oil. The oil is then emulsified as tiny droplets dispersed in lamellae, giving very stable pseudoemulsion films inhibiting rupture of the bubble films. This made it possible to utilize typical conventional anionic surfactants as foaming agents in foam flooding.     

Preparation and properties of poly(WPSF‐co‐butyl acrylate) copolymer emulsion with ultrasonic radiation II. Monomer conversion rate and characterization

A stable emulsion of poly(WPSF‐co‐butyl acrylate) based on butyl acrylate, waste polystyrene foam was synthesized through emulsion polymerization using sodium dodecyl sulfate and octyl phenyl polyoxyethylene ether as surfactant, ammonium persulfate and sodium hydrogen bisulfate as mixed redox initiator, under ultrasound irradiation in the absence of inert gas. The effects of various copolymerization conditions on the monomer conversion were reported. The copolymers were characterized by means of IR, ¹HNMR, and gel permeation chromatography. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Synthesis and Properties of N-Dodecyl Aspartic Acid and Its Sodium Salt

A novel zwitterionic surfactant N‐dodecyl aspartic acid was synthesized with dodecylamine, maleic acid anhydride and sodium hydroxide in ethanol–water as the solvent. The chemical structure of N‐dodecyl aspartic acid was characterized by IR, ¹H NMR and MS. The surface properties of the surfactant were studied by measuring the equilibrium surface tensions of the dilute aqueous solutions. The synthesized surfactant can reduce the surface tension of water to 29–32 mN m^?1 at temperatures of 298–313 K, the surface activity reaches its highest under mild pH conditions. The water hardness has almost no effect on foam power and foam stability of the surfactant at lower and middle water hardnesses.     

水性含氟丙烯酸酯共聚物的疏水性研究

以脂肪醇聚氧乙烯醚/十二烷基硫酸钠/阴离子含氟乳化剂(AEO/SDS/FSA)为复合乳化剂体系,以甲基丙烯酸十二氟庚酯(FMA)、丙烯酸丁酯和甲基丙烯酸甲酯等原料合成了稳定的水性含氟丙烯酸酯共聚物(PFA)。考察了FSA用量对聚合反应稳定性的影响,并研究了FMA用量和FSA用量等因素对PFA疏水性的影响规律。     

Emulsion polymerization of styrene: Simulation the effects of mixed ionic and non-ionic surfactant system in the presence of coagulation

A detailed model was developed for emulsion polymerization of styrene in batch reactor to predict the evolution of the product particle size distribution. The effect of binary surfactant systems (ionic/non-ionic surfactants) with different compositions was studied. The zero–one kinetics was employed for the nucleation rate, with the model comprising a set of rigorously developed population balance equations. The modeling incorporated particle formation by both nucleation and coagulation phenomena. The partial differential equations describing the particle population were discretized using finite volume elements. Binary surfactant systems, comprising sodium dodecyl sulfate (SDS) as anionic, and a commercial polyether polyol (Brij35^®) as non-ionic surfactants, were examined with different mass ratios. Increasing non-ionic surfactant mass fraction in binary surfactant system showed the decrease of particle number due to intensifying the coagulation between particles. Broader particle size distributions with greater average particle size were obtained with non-ionic surfactant comparing those obtained with anionic one.     

Probing the carbon nanotube-surfactant interaction for the preparation of composites

Adsorption isotherms of four different surfactants, sodium dodecyl sulfate (SDS), sodium dodecyl benzyl sulfonate, benzethonium chloride and Triton X-100 were measured on multi-wall carbon nanotubes (MWCNT) in water. With the surfactant SDS, the isotherms were also measured on single-wall carbon nanotubes (SWCNT) as well as on MWCNT under various ionic strength and temperature conditions. The nature of the polar head had only little influence on adsorption which was mainly driven by hydrophobic interactions. However, the outcome of the dispersion experiment was dependent on the purity of the carbon nanotubes. Using these results, it was possible to prepare concentrated colloidaly stable dispersions of MWCNTs in water (c = 32 g/L). Conducting MWCNT/polymer composite films could then readily be prepared by simple formulation of the MWCNTs with a polymeric dispersion.     

Polyaniline and polypyrrole prepared in the presence of surfactants: a comparative conductivity study

Polyaniline and polypyrrole have been prepared by chemical oxidative polymerization of the corresponding monomers in an aqueous medium containing an anionic surfactant—sodium bis(2-ethylhexyl) sulfosuccinate, dodecylbenzenesulfonic acid and its sodium salt, and sodium dodecyl sulfate. Determination of the yield, elemental composition and density proved, and FTIR spectroscopy confirmed, that the anionic surfactants become incorporated in the conducting polymers. The polymerizations in the presence of a cationic surfactant, tetradecyltrimethylammonium bromide, were carried out for comparison. While the conductivity of polypyrrole became enhanced after the introduction of an anionic surfactant, the changes in the conductivity of polyaniline were marginal. The conductivity changes in both polymers during thermal ageing were measured at 175 °C. The electrical stability of polyaniline was better than that of polypyrrole. The presence of a surfactant improved the stability of conductivity of polypyrrole but reduced the electrical stability of polyaniline.     

Structure,surface tension,and rheological behaviors of hydrophobically associative polyacrylamides by self-emulsified microemulsion polymerization

Hydrophobically associating copolymers using acrylamide (AM), acrylic acid (AA), and Styrene (St) as comonomers were successfully prepared by self-emulsified microemulsion polymerization, in which low-molecular-weight AM/AA/St copolymers as surfactant and AM as cosurfactant. The structure and chemical composition of AM/AA/St copolymers were characterized by Fourier transform infrared, nuclear magnetic (NMR), and differential scanning calorimeter. The content of PSt in the copolymers is determined by ¹H nuclear magnetic resonance spectra, suggesting that the self-made polymer surfactant can disperse uniformly the St monomers to improve the copolymerization efficiency. Furthermore, the polymerization mechanism of the self-emulsified microemulsion method is explored preliminarily. During the synthesis of the copolymers, the purified copolymer solution is obtained in one step without using a small molecular emulsifier such as sodium dodecyl sulfate, in order to avoid the complicated post-treatment process of the small molecular emulsifier. The copolymers revealed good hydrophobic association properties and low surface tension.     

Effects of surfactants on acrylonitrile polymerization initiated by a Cr(VI)–cyclohexanone redox system: A kinetic study

The polymerization of acrylonitrile (AN) was kinetically studied with a Cr(VI)–cyclohexanone (CH) redox system as an initiator from 25 to 45° C in the presence of a surfactant. The rate of polymerization and the percentage of the monomer conversion increased as the concentration of the anionic surfactant [sodium dodecyl sulfate (SDS)] increased above its critical micelle concentration. However, the cationic surfactant (cetyltrimethylammonium bromide) reduced the rate considerably at higher concentrations, whereas the nonionic surfactant (TX‐100) had no effect on the rate. The effects of the Cr(VI), CH, AN, and H⁺ concentrations and the ionic strength on the rates were also examined. The presence of 0.015M SDS reduced the overall activation energy of the polymerization by 5.55 kcal/mol with respect to that in the absence of the surfactant. With increasing SDS concentration, the viscosity‐average molecular weight also increased. A suitable mechanistic scheme was proposed for the polymerization process. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 1147–1153, 2004     

Preparation and characterization of polysiloxane–polyacrylates composite latices and their film properties

Gamma‐ray induced seeded emulsion polymerization of methyl methacrylate and butyl acrylate was carried out in the presence of a polymerizable polysiloxane seed latex, obtained by ring‐opening copolymerization of octamethyl cyclotetrasiloxane (D₄) and tetramethyl tetravinyl cyclotetrasiloxane (VD₄), catalyzed by dodecylbenzene sulfonic acid (DBSA). A series of polysiloxane seed latices with different molecular weights, vinyl contents and particle sizes was used. The conversion–time curve showed that the polymerization rate was accelerated significantly by the seed latex. The obtained composite latices also showed good storage stability, mechanical stability and high electrolyte resistance ability. By using transmission electron microscopy (TEM), the morphology of the composite latex particles was found to display a quite uniform fine structure. The graft polymerization reactions between the polymerizable polysiloxane and the acrylates were confirmed by Fourier‐transform infrared spectroscopy (FT‐IR) and the graft efficiencies were also studied. The influence of seed content, molecular weight, vinyl content of the polysiloxane and seed latex particles size on the mechanical performance, water absorption ratio, surface properties and transparency of the latex films was also investigated. It was found that the seed content and particles size greatly affect the mechanical performance, water absorption ratio and transparency of the latex films. Copyright © 2005 Society of Chemical Industry