Water-containing resin based on unsaturated polyester

Unsaturated polyester resins containing water were prepared through two steps: formation of a stable W/O emulsion of polyester prepolymer and subsequent polymerization of the emulsion. In this paper, conditions for formation of the resins from the W/O type emulsion and the heat-protection properties of the resulting water-containing resins are reported. The stability of the emulsions was measured, and the results are discussed in relation to the gelation time, since the polymerization of the emulsions is required to proceed faster than their disintegration. It was found that with increasing viscosity of the emulsions their stability increases and the gelation time shortens. The above requirement is fulfilled at almost all regions of emulsifier concentration where stable W/O emulsions are formed. Water-containing unsaturated polyester resins exhibit a remarkable heat-protection effect at elevated temperatures (500 and 2500°C.) in comparison with polyester resins not containing water.     

稳定的聚酯乳液的制备和在建筑工业中的应用

本文介绍了一种由水和不饱和聚酯树脂混合而成的乳液 ,这种乳液很稳定 ,当加入一种凝固剂时 (水泥 )也不会发生破乳现象。这种凝固剂可与乳液中的水发生水合作用而使乳液硬化 ,制成聚酯乳液混凝土。     

不饱和聚酯树脂微乳液的快速固化研究

探讨了过氧化物 (过氧化甲乙酮、过氧化氢、叔丁基过氧化氢、异丙苯过氧化氢 ) /抗坏血酸组成的氧化 -还原引发聚合体系对磺酸盐不饱和聚酯树脂及其油包水型微乳液的固化特性。结果表明 :磺酸盐不饱和聚酯树脂的凝胶时间和固化时间都比相应的微乳液长。 4种过氧化物中 ,过氧化氢的常温引发聚合反应最快 ,能使微乳液 30s内凝胶 ,7min内固化 ,达到了快速固化的目的     

低熔融黏度C-5石油树脂水基乳液的制备

以56#半精炼石蜡为黏度调节剂,制备了低熔融黏度的C-5石油树脂水基乳液,系统考察了非离子型复合乳化剂的HLB值和用量对石油树脂乳液稳定性、乳液粒径分布、乳液黏度和乳液表面张力的影响。结果表明,添加质量分数30%的石蜡可以明显降低石油树脂的熔融黏度,使物料在较低温度下实现均匀混合;复合乳化剂的最佳HLB值为10.75;最佳用量为16%。通过正交实验确定了优选乳化工艺条件为:乳化温度98℃、乳化时间20 min、剪切速率5 000 r/min、乳化水与水相的质量比为1∶3,在该条件下可制得固体质量分数为40%,稳定性好、粒径小、黏度低的O/W型C-5石油树脂乳液。     

丙烯酸酯改性不饱和聚酯的研究

普通不饱和聚酯树脂脆性大,故有必要对其进行增韧改性。本文合理选用丙烯酸酯对不饱和聚酯树脂进行增韧及其他性能改性,制备改性不饱和聚酯树脂。研究表明,随着丙烯酸丁酯（BA）的用量增加,不饱和聚酯的断裂伸长率、冲击强度增加;但不饱和树脂的弹性模量减小、拉伸强度急剧降低,当BA的用量为10%时,弹性模量减少至1.0 GPa左右;耐水分析表明树脂的耐水性能优良;DSC差热分析表明,改性树脂的Tg值在61℃左右,满足基本的使用要求。     

气相SiO_2对环氧树脂的乳化稳定作用

研究了气相SiO2对环氧树脂E-44的乳化稳定作用。结果表明:气相SiO2的表面性质对环氧树脂E-44的乳化稳定作用有较大影响,未改性的气相SiO2没有乳化作用,阳离子表面活性剂十二烷基三甲基溴化铵(DTAB)、十六烷基三甲基溴化铵(CTAB)改性的气相SiO(2DTAB-SiO2、CTAB-SiO2)能形成较稳定的O/W乳状液,其中用浓度为1×10-3mol/L、接触角为84.1°的CTAB改性气相SiO2得到的乳状液稳定性最好。CTAB-SiO2与环氧树脂专用乳化剂EP-1合用形成的乳状液为W/O/W型多重乳液。     

Effects of emulsification variables on fuel properties of two- and three-phase biodiesel emulsions

Biodiesel has attractive fuel properties such as excellent biodegradability and lubricity, almost no emissions of sulfur oxides, PAH and n-PAH, reduced CO₂, PM and CO emission, superior combustion efficiency, etc. However, burning of biodiesel generally produces higher levels of NO_x emissions, primarily due to its high oxygen content. In this study, the emulsification technology has been considered to reduce the NO_x emission level of fossil fuel. Biodiesel, produced by means of transesterification reaction accompanied with a peroxidation process, was emulsified to form two-phase W/O and three-phase O/W/O emulsions. The effects of the emulsification variables such as hydrophilic lipophilic balance (HLB), and water content on the fuel properties and emulsion characteristics of W/O and O/W/O emulsions were investigated in this study. The experimental results show that the surfactant mixture with HLB = 13 produced the highest emulsification stability while HLB = 6 produced the lowest emulsification stability and the most significant extent of water–oil separation among the various HLB values for O/W/O biodiesel emulsion. The kinematic viscosity, specific gravity and carbon residual of the biodiesel emulsions were larger than those of the neat biodiesel. In addition, the W/O biodiesel emulsion was found to have a smaller mean droplet size, lower volumetric fraction of the dispersed phase than the O/W/O biodiesel emulsion, and the highest heating value among the test fuels, if the water content is deducted from the calculation of the heating value.     

Effects of NOx-inhibitor agent on fuel properties of three-phase biodiesel emulsions

Biodiesel is one of the more promising alternative clean fuels to fossil fuel, which can reduce the emissions of fossil fuel burning, and possibly resolve the energy crisis caused by the exhaustion of petroleum resources in the near future. The burning of biodiesel emits much less gaseous emissions and particulate matter primarily because of its dominant combustion efficiency. However, the high oxygen content in biodiesel not only promotes the burning process but also enhances NO_x formation when biodiesel is used as fuel. Biodiesel emulsion and the additive of NO_x-inhibitor agent are considered to reduce levels of NO_x emissions in this experimental study. The biodiesel was produced by transesterification reaction accompanied with peroxidation process. A three-phase biodiesel emulsion of oil-in water drops-in oil (O/W/O) and an O/W/O biodiesel emulsion containing aqueous ammonia were prepared afterwards. The effect of the existence of NO_x-inhibitor agent on the fuel properties and the emulsion characteristics of the O/W/O biodiesel emulsions were investigated. The experimental results show that the burning of the O/W/O biodiesel emulsion and the O/W/O biodiesel emulsion containing aqueous ammonia had larger fraction of fuel burnt and thus larger heat release than the neat biodiesel if water content is not considered for the calculation of heating value. The addition of aqueous ammonia within the dispersed phase of the O/W/O biodiesel emulsion appeared to deteriorate the emulsification characteristics. A smaller quantity of emulsion and greater kinematic viscosity were formed while a larger carbon residue and actual reaction-heat release also appeared for this O/W/O biodiesel emulsion. Aqueous ammonia in the O/W/O biodiesel emulsion produces a higher pH value as well. In addition, the number as well as the volumetric fraction of the dispersed water droplets is reduced for the O/W/O biodiesel emulsion that contains aqueous ammonia.     

含水不饱和聚酯树脂合成方法

本文从成盐法、乳化法和聚酯改性法三个方面综述了含水不饱和聚酯树脂的制备方法。     

The effect of the chemical structure of low-profile additives on the curing behavior and chemorheology of unsaturated polyester resin

An experimental study was conducted to investigate the effect of the chemical structure of low-profile additives on the curing behavior and chemorheology of unsaturated polyester resin during isothermal cure. For the study a general-purpose unsaturated polyester resin was cured in the presence of t-butyl perbenzoate as Initiator. The curing behavior of the resin was investigated using differential scanning calorimetry (DSC). Three different thermoplastic low-profile additives were used, namely poly(vinyl acetate) (PVAc), poly(styrene-co-butadiene), which is also known as KRATON DX-1300, and dehydrochlorinated Isobutylene/isoprene copolymer, often referred to as conjugated diene butyl (CDB) rubber. Each of the these additives, about 30 weight percent, was first dissolved in styrene. The solution was then mixed with unsaturated polyester resin and CaCO₃. The CaCO₃ particles helped stabilize the emulsions consisting of resin and KRATCN, and of resin and CDB. For each resin formulation, a series of isothermal DSC runs were made at various levels of cure pressure. It was found that for all three low-profile resins investigated, the final degree of cure went through a maximum as cure pressure was increased from atmospheric to 6.21 MPa (900 psi). We have observed evidence that in the presence of an initiator generating free radicals, the unsaturated double bonds in the KRATON and CDB undergo grafting reactions with the styrene monomers and unsaturated polyester resin, increasing the glass transition temperature of KRATON and CDB, to an extent which varies with the cure conditions employed. Both steady and oscillatory shearing flow properties were determined using a cone-and-plate rheometer. The rheological measurements indicate that the resin/CaCO₃/KRATON and resin/CaCO₃/CDB systems give rise to gel times shorter than the resin/CaCO₃/PVAc system. It is concluded that both KRATON and CDB are more effective, both for enhancing the rate of cure of unsaturated polyester resin and imparting impact properties to the cured composites, than those thermoplastic low-profile additives that contain neither unsaturated double bonds nor a chemical structure that has rubber-like properties in the solid state.     

An experimental study of stability of oil–water emulsion

There has been much interest in alternative fuels made from coal which is much more abundant than oil. The coal–oil–water slurry is a new type of oil-based synfuel composed of finely pulverized coal, oil and water. It has lower viscosity, lower ignition point and higher heating value than coal–water slurry. The preparation of stable water-in-oil (W/O) emulsion is critical for the success of production of stable coal–oil–water slurry. The present study was undertaken to experimentally investigate the effects of different process variables on emulsion stability. The emulsion was prepared using 100 ml colloid mill with sorbitan monooleate (SM) as emulsifier. The variables studied include emulsifier dosage, ratio of oil to water, stirring intensity, emulsifying temperature and mixing time. The results showed that the optimum process conditions are: emulsifier dosage, 0.5%; oil to water ratio, 1:1; stirring intensity, 2500 rpm; and mixing temperature, 30 °C.     

Stability of vitamin A in oil-in-water-in-oil-type multiple emulsions

The stabilityof vitamin A was studied in thee different emulsions: oil-in-water (O/W), water-in-oil (W/O), and oil-in-water-in-oil (O/W/O). The stability of retinol (vitamin A alcohol) in the O/W/O emulsion was the highest among the thee types of emulsions; remaining percentages at 50°C after 4 wk in the O/W/O, W/O, and O/W emulsions were 56.9, 45.7, and 32.3, respectively. With increasing peroxide value of O/W and W/O emulsifiers, the remaining percentage of vitamin A palmitate and retinol in the emulsions decreased significantly, indicating that peroxides in the formulae accelerate the decomposition of vitamin A. Organophilic clay mineral (an oil gelling agent and a W/O emulsifier) also affected the stability of retinol; synthesized saponite was better than naturally occurring bentonite for retinol stability. The stability of retinol in the O/W/O emulsion increased with increasing inner oil phase ratio (φ_i), whereas in O/W it was unaffected by φ_i. Encapsulation percent of retinol in the O/W/O emulsion, the ratio of retinol in the inner oil phase to the total amount in the emulsion, increased with increasing φ_i. The remaining percent of retinol in the O/W/O emulsion was in excellent agreement with encapsulation percent, suggesting that retinol in the inner oil phase is more stable than that in the outer oil phase. Addition of antioxidants (tert-butylhydroxytoluene, sodium ascorbate, and EDTA) to the O/W/O emulsion improved the stability of retinol up to 77.1% at 50°C after 4 wk. We conclude that the O/W/O emulsion is a useful formula to stabilize vitamin A.     

Unsaturated polyester resin/graphite nanosheet conducting composites with a low percolation threshold

In this study, the unsaturated polyester resin/graphite nanosheet conducting composites with a low percolation threshold of 0.64 vol% have been prepared via in situ polymerization under the application of ultrasonic irradiation. Two theoretical approaches (mean-field theory and excluded volume theory) are applied to interpret this low critical volume fraction and the latter can explain the low value better. The microstructures reveal that low value of percolation threshold may be mainly attributed to better conductive network consisting of graphite nanosheet with special morphology and there exists contact resistance in the percolating network formed within unsaturated polyester resin/graphite nanosheet composites. Furthermore, preliminary studies on the influence of graphite nanosheet on the thermal stability of the host unsaturated polyester resin have been performed.     

含水不饱和聚酯的动态流变行为和微观结构

使用三乙醇胺(TEA)和Span80复合乳化剂制备含水不饱和聚酯树脂,改变水/乳化剂的比率(W/E)和TEA∶Span80复合比例,通过动态流变法研究含水不饱和聚酯树脂乳液的流变性质,结合光学显微镜和SEM扫描电镜分析微观结构,并测试固化树脂材料的力学性能。实验表明在一定含水量和乳化剂复合比例下,可以制备出乳胶粒子界面膜强度高,粒子数密度高,分布均匀,且乳液稳定性好的含水不饱和聚酯(WCUP)树脂,得到力学强度高的固化树脂,并得到了复合乳液黏度随应力和频率的流变规律。最佳配比TEA∶Span80=9.0∶1.0,W/E=19.2时,其树脂固化体系的拉伸强度和冲击强度比单使用TEA体系分别提高了34%和67%。     

低苯乙烯散发不饱和聚酯树脂研究

用单官能团醇对不饱和聚酯树脂改性，合成了苯乙烯含量为30％的W01树脂，对W01树脂的挥发性和反应性进行了测定，研究了成膜助剂对W01树脂性能的影响，并与通用型191树脂和一种亚克力板层间粘合用不饱和聚酯商品树脂进行了比较；指出结合成膜助剂的W01树脂能进一步降低苯乙烯的散发。     

Engine performance and emission characteristics of a three-phase emulsion of biodiesel produced by peroxidation

Biodiesel, which is produced from vegetable oils, animal fats or used cooking oils, can be used as an alternative fuel for diesel engines. The high oxygen content of biodiesel not only enhances its burning efficiency, but also generally promotes the formation of more nitrogen oxides (NO_x) during the burning process. Fuel emulsification and the use of NO_x inhibitor agents in fuel are considered to be effective in reducing NO_x emissions. In the study reported herein, soybean oil was used as raw oil to produce biodiesel by transesterification reaction accompanied by peroxidation to further improve the fuel properties of the biodiesel, which was water washed and distilled to remove un-reacted methanol, water, and other impurities. The biodiesel product was then emulsified with distilled water and emulsifying surfactant by a high-speed mechanical homogenizer to produce a three-phase oil-droplets-in-water-droplets-in-oil (i.e. O/W/O) biodiesel emulsion and an O/W/O emulsion that contained aqueous ammonia, which is a NO_x inhibitor agent. A four-stroke diesel engine, in combination with an eddy-current dynamometer, was used to investigate the engine performance and emission characteristics of the biodiesel, the O/W/O biodiesel emulsion, the O/W/O biodiesel emulsion that contained aqueous ammonia, and ASTM No. 2D diesel. The experimental results show that the O/W/O emulsion has the lowest carbon dioxide (CO₂) emissions, exhaust gas temperature, and heating value, and the largest brake specific fuel consumption, fuel consumption rate, and kinematic viscosity of the four tested fuels. The increase of engine speed causes the increase of equivalence ratio, exhaust gas temperature, CO₂ emissions, fuel consumption rate, and brake specific fuel consumption, but a decrease of NO_x emissions. Moreover, the existence of aqueous ammonia in the O/W/O biodiesel emulsion curtails NO_x formation, thus resulting in the lowest NO_x emissions among the four tested fuels in burning the O/W/O biodiesel emulsion that contained aqueous ammonia.     

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     

Destabilization‐Enhanced Centrifugation of Metalworking Oil‐in‐Water Emulsions: Effect of Demulsifying Agents

The effect of a commercial flocculant (Alpacon® WS009) and two coagulant salts (CaCl₂ and AlCl₃) on the stability of metalworking oil‐in‐water (O/W) emulsions was examined. Two O/W emulsions were tested: a fresh emulsion, prepared in the laboratory from a commercial concentrate, and a waste metalworking emulsion, provided by a local waste management company, with initial oil concentrations of 32900 and 16900 mg/L, respectively. The emulsion stability was studied at different demulsifier concentrations, temperatures and pH through centrifugation tests, zeta potential and multiple light scattering measurements. Emulsion breakdown is explained by electrostatic repulsion of oil droplets and steric interactions. The former was observed for the laboratory emulsion, while the latter was observed for the waste emulsion. Aluminum chloride was the only effective agent for demulsifying both emulsions.     

低苯乙烯散发不饱和聚酯树脂研究

用单官能团醇对不饱和聚酯树脂改性，合成了苯乙烯质量分数为30％和W01树脂，对W01树脂的挥发性和反应性进行了测定，研究了成膜助剂对01树脂性能的影响，并与通用型191树脂和一种亚克力板层间粘合用不饱和聚酯树脂进行了比较；指出结合成膜助剂的W01树脂进一步降低苯乙烯的散发。     

A novel method for preparing oil-in-water-in-oil type multiple emulsions using organophilic montmorillonite clay mineral

A stable formula using oil-in-water-in-oil (O/W/O) type multiple emulsions was investigated. The components consisted of hydrophilic nonionic surfactant (HCO-60), organophilic montmorillonite, and lipophilic nonionic surfactant (DIS-14). O/W/O emulsions were prepared by a double-step procedure in which an O/W emulsion was prepared in the first step, and then the O/W emulsion was “re-emulsified” in an oil phase with organophilic montmorillonite. The diameter of the innermost oil droplets decreased with increasing HCO-60 content (0.1–3%), while the viscosity showed a maximum at 1% of HCO-60, indicating that the yiel of re-emulsification is highest at this condition. Viscosity of the O/W/O emulsion increased with increasing organophilic montmorillonite and DIS-14. According to the results of a phase ratio study, viscosity and stability of the O/W/O emulsion decreased at high weight fraction of inner oil phase (0.4–0.5), indicating that the excess amount of inner oil phase is absorbed by the outer oil phase. These results revealed that the weight fraction of inner oil phase should be kept below 0.3 for a stable O/W/O emulsion. A similar study on the weight fraction of O/W phase [фO/W)/O] suggested that the O/W/O emulsion is stable at ϕ(O/W)/O=0.65–0.70.