Synthesis of water‐reducible acrylic–alkyd resins based on modified palm oil

Water‐reducible acrylic–alkyd resins were synthesized from the reaction between monoglycerides prepared from modified palm oil and carboxy‐functional acrylic copolymer followed by neutralization of carboxyl groups with diethanolamine. Modified palm oil was produced by interesterification of palm oil with tung oil at a weight ratio of 1 : 1, using sodium hydroxide as a catalyst, whereas carboxy‐functional acrylic copolymer was prepared by radical copolymerization of n‐butyl methacrylate and maleic anhydride. The amount of acrylic copolymer used was from 15 to 40% by weight, and it was found that homogeneous resins was obtained when the copolymer content was 20–35 wt %. All of the prepared water‐reducible acrylic–alkyd resins were yellowish viscous liquids. Their films were dried by baking at 190°C and their properties were determined. These films showed excellent water and acid resistance and good alkali resistance. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 96: 1170–1175, 2005     

Emulsification, drying and film formation of alkyd emulsions

A method was developed and optimised for the emulsification of a conventional short oil alkyd resin which was solid at room temperature. The method was based on the emulsion inversion point (EIP) method whereby hot water (90°C) was added to molten alkyd resin (90°C) containing the emulsifier. Under slow mixing and addition of water, a point was reached where the emulsion instantaneously phase inverted from a water in oil emulsion (W/O) to an oil in water emulsion (O/W). Using optimum conditions, emulsions with droplet of diameters less than 0.8 μm were obtained. The drying and film formation of long oil alkyd emulsions were investigated with emphasis on loss of dry upon storage. The main reason for loss of dry was adsorption of the cobalt (drier) on pigment surfaces as a precipitated hydroxide. Titanium dioxides with alumina surface treatment and organic pigments were most detrimental to drying. Acrylate- and phosphate-based dispersants also deactivated cobalt presumably due to complexation and precipitation of cobalt. Emulsions prepared with an emulsifiable cobalt drier containing 2,2′-bipyridyl (complexing agent for cobalt) showed the best resistance to loss of dry. Films formed from the emulsions showed that surfactant migrated to the film surface which when washed with water leaves holes or pits in film. The pits were arranged in a hexagonal pattern, characteristic of Bénard cells which form due to interfacial tension gradients generated in the film during evaporation of water.     

Metastable boundary conditions of water‐in‐oil emulsions in the hydrate formation region

A stepwise pressurization method was proposed for determining the metastable boundary conditions of water‐in‐oil emulsions in the hydrate formation region. The metastable boundary pressures of four water‐in‐n‐octane emulsions in the presence of methane gas were determined at four specified temperatures. The experimental results show that the metastable boundary pressures increase with decreasing water droplet sizes. A thermodynamic model was developed for calculating the metastable boundary conditions of a water‐in‐oil emulsion in which assuming that the collapse of a metastable emulsion requires the formation of a stable hydrate film with a critical thickness on the surfaces of water droplets. The model was used to correlate the experimental data and determine the critical thickness of the hydrate film. It was demonstrated that the calculated results were in good agreement with the experimental data. The determined critical thickness is at nanoscale, ranging from 14 to 40 nm, which decreases with decreasing water droplet sizes. © 2011 American Institute of Chemical Engineers AIChE J, 2012     

Alkyd emulsions

Various aspects of alkyd emulsion technology have been investigated. The influence of alkyd oil length, acid value and hydroxyl number and type of surfactant used as emulsifier, on shear stability of alkyds emulsions have been studied. It was found that the acid value was the most important alkyd parameter, the stability increasing with increasing oil length. It is also shown that anionic surfactants give emulsions with small droplet sizes at lower concentrations than do nonionics. Polymerizable nonionic surfactants have been tested as emulsifiers and compared with conventional surfactants of the same hydrophilic lipophilic balance (HLB). It was found that surfactants capable of participating in the autoridative curing process give faster drying and improved film hardness compared with nonreactive surfactants. The distribution of driers between the alkyd phase and the water phase has been investigated. It was found that low pH and the use of hydrophilic anionic surfactants, such as sodium dodecyl sulphate, favour partitioning of cobalt into the aqueous phase which is unfavourable with respect to drying properties.     

In situ surfactant generation as a means of miniemulsification?

In situ emulsification, where the surfactant is synthesized spontaneously at the oil/water interface, has been put forth as a simpler method for the preparation of miniemulsions‐like systems. Miniemulsions are relatively stable oil‐(e.g., monomer)‐in‐water emulsions having droplet sizes anywhere in the range of 50–500 nm, and are typically created with high shear and stabilized by the combination a surfactant and a costabilizer. Using the in situ method of preparation, emulsion stability and droplet and particle sizes were monitored and compared with conventional emulsions and miniemulsions. Styrene emulsions prepared by the in situ method do not demonstrate the stability of a comparable miniemulsion. Upon polymerization, the final particle size generated from the in situ emulsion did not differ significantly from the comparable conventional emulsion polymerization; the reaction mechanism for in situ emulsions is more like conventional emulsion polymerization rather than miniemulsion polymerization. Similar results were found when the in situ method was applied to controlled free radical polymerizations (CFRP), which have been advanced as a potential application of the method. Molecular weight control was found to be achieved via diffusion of the CFRP agents through the aqueous phase owing to limited water solubilities. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

水性苯丙共聚物改性醇酸树脂的制备及性能

以油酸、季戊四醇、邻苯二甲酸酐、苯甲酸为原料,采用丙二醇甲醚醋酸酯（PMA）为溶剂合成了基体醇酸树脂;用过氧化苯甲酰、过氧化苯甲酸叔丁酯双引发剂、分步引发烯类单体共聚,制备了一种苯丙烯树脂,并对醇酸树脂改性制得了水性醇酸树脂。考察了不同油度对水性醇酸树脂结构与性能的影响。通过FTIR、TGA、DLS分别对树脂的结构、稳定性和乳液性能进行了表征。测定了树脂的漆膜性能,包括耐水性、表干时间、硬度、电化学性能。结果表明,n（油酸）∶n（季戊四醇）∶n(邻苯二甲酸酐)∶n（苯甲酸）=1∶1∶1∶0.3,油度为47%时,聚合物乳液粒径为74.4 nm,PDI为0.262,胶膜的吸水率为14.5%,接触角为70.87?,有较好的耐水性。改性醇酸树脂的表干时间缩短为0.5 h,实干时间缩短为24 h,硬度达HB。     

Studies on the preparation of Parinari polyandra benth seed oil alkyd resins

Parinari polyandra Benth seed oil was utilized in the preparation of four sets of alkyd resin (35%, 50%, 60%, and 75% oil formulations) using a two‐stage alcoholysis‐polyesterification method. The rate of polyesterification was depended on the amount of oil used during synthesis. The properties of the alkyds (drying times, film characteristics, water and acid resistances, and solubility) were evaluated using relevant standards. Inclusion of cobalt naphthenate drier in the alkyds and their exposure to outdoor temperature improved the drying properties. White gloss paints formulated from the alkyds, considering a pigment‐volume concentration of 20.67% in the gloss paint formulation compare well with commercial standard. FTIR and ¹H‐NMR analysis confirm the alkyd (glycerol‐phthalate) structure. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Effects of droplet size on the oxidative stability of oil-in-water emulsions

The effects of droplet size and emulsifiers on oxidative stability of polyunsaturated TAG in oil-in-water (o/w) emulsions with droplet sizes of 0.806±0.0690, 3.28±0.0660, or 10.7±0.106 μm (mean ± SD) were investigated. Hydroperoxide contents in the emulsion with a mean droplet size of 0.831 μm were significantly lower than those in the emulsion with a mean droplet size of 12.8 μm for up to 120 h of oxidation time. Residual oxygen contents in the headspace air of the vials containing an o/w emulsion with a mean droplet size of 0.831 μm were lower compared with those of the emulsion with a mean droplet size of 12.8 μm. Hexanal developed from soybean oil TAG o/w emulsions with smaller droplet size showed significantly lower residual oxygen contents than those of the larger droplet size emulsions. Consequently, oxidative stability of TAG in o/w emulsions could be controlled by the size of oil droplet even though the origins of TAG were different. Spin-spin relaxation time of protons of acyl residues on TAG in o/w emulsions measured by ¹H NMR suggested that motional frequency of some acyl residues was shorter in o/w emulsions with a smaller droplet size. The effect of the wedge associated with hydrophobic acyl residues of emulsifiers was proposed as a possible mechanism to explain differences in oxidative stability between o/w emulsions with different droplet sizes.     

Stability Assessment of Virgin Coconut Oil‐Based Emulsion Products

In recent years, there has been dramatic growth in the market for virgin coconut oil (VCO). VCO, a promising functional food oil, has gained popularity and captured public attention worldwide. Two VCO‐based emulsion products were developed as a new nutritional food supplement with the aim of increasing the consumption of VCO. The stability of VCO‐based emulsion products was assessed during a storage period of 3 months to gauge the quality of the optimized VCO‐based emulsions. The particle‐size distributions of the VCO‐based emulsions remained stable throughout the 3‐month storage period at 25 and at 50°C. However, a slight increase in the particle sizes was observed in the VCO‐based emulsions samples after 2 months of storage at 4 °C. Nevertheless, phase separation did not occur in either of the VCO‐based emulsions products throughout the storage‐stability assessment period. No signs of microbial growth were detected in the emulsion products during the storage period. Furthermore, no significant changes in the free fatty acid contents of the emulsion products were observed during storage at 4 or 25°C throughout the storage period. The VCO‐based emulsion products possessed sufficient emulsion stability to withstand changes at different storage temperatures.     

Water‐based crosslinkable coatings via miniemulsion polymerization of acrylic monomers in the presence of unsaturated polyester resin

Hybrid miniemulsion polymerization was performed with a three‐component acrylic system of methyl methacrylate, butyl acrylate, and acrylic acid in the presence of a Bayer® Roskydal TPLS2190 unsaturated polyester resin. Latexes were obtained in which the polyester resin was grafted to the acrylic polymer, forming a water‐based crosslinkable coating. Grafting between the resinous component and the acrylic polymer is a feature different from the work of others who have attempted to combine the properties of both systems in water‐based blends. Both emulsions and latexes were shelf‐stable for over 6 months, shear‐stable, and resistant to at least one freeze/thaw cycle. Resin‐to‐monomer ratios were studied as high as 1 : 1 (wt : wt), and total emulsion solids, as high as 45%. Monomer droplet and latex particle sizes were similar, suggesting evidence of the preponderance of droplet nucleation. A high level of crosslinking (>70%) during polymerization was observed in this particular hybrid system in contrast to those involving alkyd or polyurethane resins (<5%). Films, both homogeneous and hard, were achieved with exceptional adhesion. Electron microscopy showed the hybrid particle morphology to have internal domains of polyester resin in an acrylic matrix. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 75: 916–927, 2000     

Factors influencing the stability and film properties of acrylic/alkyd water-reducible hybrid systems using a response surface technique

Acrylic-grafted-alkyd resins were prepared by free radical chemistry. Long, medium, and short oil alkyds were prepared using soybean oil, glycerol, phthalic anhydride (PA), and tetrahydrophthalic anhydride (THPA) and used as the alkyd phase. Acrylic co-monomer formulas containing methyl methacrylate (MMA), butyl acrylate (BA), methacrylic acid (MAA), and vinyl trimethoxysilane (VTMS) were polymerized in the presence of the different alkyds using 2,2′-azobisisobutyronitrile (AIBN) as the initiator to obtain the final grafted structures. Design of experiments was used to understand how different variables in the synthesis of the acrylated-alkyds affect the film performance. A Box–Behnkin design was used, varying the oil length of the alkyd phase, the degree of unsaturation in the polyester backbone, and acrylic to alkyd ratio. Acrylic–alkyd hybrid resins were reduced with an amine/water mixture. The hydrolytic stability of hybrid alkyd dispersed in water was evaluated. Cured films were prepared and basic coatings properties were also evaluated. It was found that the oil length of the alkyd is the most dominant factor for final coatings properties of the resins. The hydrolytic stability was dependent on the acrylic to alkyd ratio. The oil length of the alkyd backbone had a minimal effect on stability of the resin and film performance.     

Emulsifier type,metal chelation and pH affect oxidative stability of n‐3‐enriched emulsions

Recent research has shown that the oxidative stability of oil‐in‐water emulsions is affected by the type of surfactant used as emulsifier. The aim of this study was to evaluate the effect of real food emulsifiers as well as metal chelation by EDTA and pH on the oxidative stability of a 10% n‐3‐enriched oil‐in‐water emulsion. The selected food emulsifiers were Tween 80, Citrem, sodium caseinate and lecithin. Lipid oxidation was evaluated by determination of peroxide values and secondary volatile oxidation products. Moreover, the zeta potential and the droplet sizes were determined. Tween resulted in the least oxidatively stable emulsions, followed by Citrem. When iron was present, caseinate‐stabilized emulsions oxidized slower than lecithin emulsions at pH 3, whereas the opposite was the case at pH 7. Oxidation generally progressed faster at pH 3 than at pH 7, irrespective of the addition of iron. EDTA generally reduced oxidation, as evaluated by volatiles formation in all emulsions, irrespective of pH and emulsifier type, except in the lecithin and caseinate emulsions where a pro‐oxidative effect was observed for some volatiles. The different effects of the emulsifier types could be related to their ability to chelate iron, scavenge free radicals, interfere with interactions between the lipid hydroperoxides and iron as well as to form a physical barrier around the oil droplets.     

Experimental characterization of emulsion formation and coalescence by nuclear magnetic resonance restricted diffusion techniques

Nuclear magnetic resonance (NMR) is explored as a technique for noninvasively monitoring emulsion droplet formation and destabilization. The method makes use of the fact that the diffusion of oil molecules within oil-in-water emulsion droplets results in attenuation of a coherent magnetic signal that emanates from those molecules. If oil diffusion is limited by the size of the droplet, the shape of a plot of attenuation over time is directly affected by the droplet radius. We use this approach to determine noninvasively the effect of surfactant type, surfactant concentration, pH, and ionic strength on droplet sizes within a 40 wt% octane and water emulsion, stabilized by Tween 20 or β-lactoglobulin (β-Lg). We find that addition of the low-molecular-weight Tween 20 forms finer emulsion droplets than does addition of the protein, and that the Tween 20 emulsion is sensitive to surfactant concentration below a threshold “saturation” concentration. The droplet sizes in β-Lg-containing emulsions increase as pH increases above the isoelectric point and as ionic strength increases. The fact that the NMR technique does not mistake clusters of droplets for single large droplets makes the analysis of these effects unambiguous. We further extend the use of NMR diffusion techniques to monitor the effect of surfactant type, surfactant concentration, and convection on the rate of droplet coalescence. The ability of NMR methods to distinguish between large single droplets and droplet clusters makes it well-suited to monitor coalescence processes independently from flocculation.     

Laboratory investigation of inversion of heavy oil emulsions

Laboratory investigations have been undertaken to assess the suitability of heavy oil‐in water emulsions for pipeline transportation. The emulsions contained 65% oil in water and were prepared using polyethoxy nonylphenol surfactants. Two methods were employed for simulating the shear process which accompanies pipeline flow: a bench scale stirred vessel and a rotated pipe toroid. The progress of the emulsions towards inversion, at which point the oil becomes the continuous phase, was followed by measuring the surfactant concentration in the aqueous phase using liquid chromatography. At inversion the surfactant concentration falls below the threshold level required to sustain an oil‐in‐water emulsion. The experiments showed that the lifetime of the emulsion depends upon the initial surfactant dosage, the solids content of the oil, the intensity of shear and the nature of the shear process. Laminar flow was found to be less desirable than turbulent flow.     

Preparation and characterization of water reducible alkyd resin/colloidal silica nanocomposite coatings

In this study, water reducible alkyd resins containing different amounts of colloidal silica were synthesized for the first time. In order to achieve this, alkyd resin, which has an oil content of 35%, was prepared with tall oil fatty acid, isophthalic acid, trimellitic anhydride, and trimethylolpropane. The alkyd resin was neutralized with triethylamine, and was dissolved in an isobutyl alcohol-isopropyl alcohol-butyl glycol mixture to produce 75% (wt.) solution, which was called stock alkyd resin. The stock alkyd resin was diluted with water to 50% (wt.) concentration with water and colloidal silica mixture in order to prepare an alkyd solution containing 0%, 5%, 10%, 15% and 20% colloidal silica. Then the effect of the silica nanoparticle addition on the surface coating properties, thermal behaviors and surface morphologies of water reducible alkyd resins was investigated. As a result, the addition of colloidal silica has improved surface coating properties and thermal behaviors of nanocomposite water reducible alkyd resin.     

Parameter Selection of Emulsification Processes: Conditions for Nano‐ and Macroemulsions

Beside factors like nature of the emulsifier as well as rheology of the interface and continuous phase, the droplet size distribution of an emulsion governs emulsion properties such as long‐term stability over months or years, texture, and optical appearance. Consequently, emulsions with droplets in nano‐scale are of interest when well‐defined emulsion properties are needed. The formation of emulsions consisting of water, corn oil, and nonionic surfactants using disc systems and high‐pressure homogenizers was studied. The emulsion droplet size distributions were obtained by means of a laser diffraction method. The influence of parameters affecting the emulsion formation, such as emulsification time, viscosity for the disc system, pressure, and homogenizing steps for high‐pressure homogenization, was investigated. Data to determine the effect of the surfactant type and concentration were collected for both systems. The emulsification process using a disc system was evaluated in order to highlight its advantages and limits in comparison to high‐pressure homogenization.     

改性醇酸树脂的合成

以桐油、豆油、三羟甲基丙烷、苯酐、己二酸为原料合成基础醇酸树脂 ,再用苯乙烯、丙烯酸酯进行接枝共聚就制得改性醇酸树脂。在制造醇酸树脂过程中添加适量的抗氧剂 ,就可以防止胶化。制得的产品是均匀透明的 ,可用于制造浅色的不泛黄的涂料     

The use of aminolysis,aminoglycolysis, and simultaneous aminolysis–hydrolysis products of waste PET for production of paint binder

This work is concerned with the use of aminolysis, aminoglycolysis, and simultaneous aminolysis–hydrolysis products of waste PET for production of paint binder based on alkyd resin. For this purpose, first, aminolysis, aminoglycolysis, and simultaneous hydrolysis–aminolysis reactions of waste PET were carried out in the presence of different chemical agents in xylene medium at high pressures. Reactions of waste PET flakes obtained from grinding postconsumer water bottles were carried out in an autoclave at higher temperatures. Then, four alkyd resins, formulated to have oil content 40–50%, were prepared using these depolymerization products. One of resins is “reference alkyd resin” which was prepared by using soybean oil fatty acid, phthalic anhydride, glycerine, and ethylene glycol for comparison. Other three alkyds are “depolymerization product‐based alkyd resins” in which depolymerization products is used instead of ethylene glycol. Then, the physical and chemical surface coating properties and thermal behaviors of alkyd resins films were investigated comparatively. As a result, we concluded that aminolysis, aminoglycolysis, and simultaneous aminolysis‐hydrolysis products of waste PET are suitable for manufacturing both air drying and oven curing paint binder based on alkyd resins. The film prepared from alkyd resin based on simultaneous aminolysis‐hydrolysis product showed extremely good surface coating properties and thermal stability. POLYM. ENG. SCI., 54:2272–2281, 2014. © 2013 Society of Plastics Engineers     

Effect of karawila (Momordica charantia) seed oil on synthesizing the alkyd resins based on soya bean (Glycine max) oil

Air drying long oil alkyd resins of 65% oil length were synthesized from a blend of soya bean (Glycine max) oil and karawila (Momordica charantia) seed oil. Different proportions of karawila seed oil (w/w% 10, 20, 30, 40 and 50) were blended with soya bean oil to examine the effect of karawila seed oil on the drying behavior of alkyds synthesized from soya bean oil. A sharp variation of viscosity is only observed for alkyd resins having more than 40% (w/w) of karawila seed oil. The polyesterification time was reduced and correspondingly the extent of polymerization was also reduced up to 30% (w/w). Significant variation in transesterification time was also observed for 30% (w/w). However, further increase in karawila seed oil above 40% (w/w) had only a marginal effect on the polyesterification reaction. The drying properties of the alkyd resins had been significantly improved with the increase of karawila seed oil up to 30% (w/w) but further increase in karawila seed oil resulted in poor drying characteristics. The film properties (drying time, hardness, adhesion, chemical resistance and gloss) of the alkyd resins were determined. The optimum film properties were recorded for the oil blend with 30% (w/w) karawila seed oil and 70% (w/w) soya bean oil.     

Gravity induced coalescence in emulsions with high volume fractions of dispersed phase in the presence of surfactants

We report studies on the effect of volume fraction and surfactant concentration on the kinetics of destabilization of emulsions under the influence of gravity. Model oil‐in‐water emulsions, designed to mimic crude oil–water emulsions, were prepared with varying volume fractions of dispersed oil but nearly identical normalized initial drop size distributions. The gravity separation process was observed by periodically withdrawing samples, and examining the droplet size distribution under the microscope. Experiments were performed for three volume fractions of dispersed phase and two surfactant concentrations (0.4 and 1.6% by weight). At higher oil fractions (20%) and a lower surfactant concentration (0.4%), it was observed that although the rate of coalescence increased, the actual oil separation was delayed. At higher surfactant concentrations (1.6%), the dominant factor in suppressing destabilization is the rate of drop to interface coalescence. © 2017 American Institute of Chemical Engineers AIChE J, 63: 4379–4389, 2017