Anionic Emulsion Research Articles

Synthesis of Novel Anionic Fluorinated Polyacrylate Emulsion and its Application in Leather Waterproofing

Novel anionic fluorinated polyacrylate emulsion (FLHA) was synthesized and characterized using Infrared spectrum (IR). Then it was used as waterproofing agent to treat wet blue leather and the effects of various parameters, such as dose of fluorinated acrylate emulsion, processing time, temperature, etc., on hydrophobic property of the treated crust leather were also investigated using single factor experimental method. Results showed that water contact angle (WCA) on the grain and flesh layers of the resultant leather had similar rule controled by dose of the FLHA, processing time and temperature and increased with augment of those factors. The most preferable processing parameters of the above factors were 6% (based on the weight of the treated wet blue leather), 60 minutes and 30 °C, repectively. Thus, WCA on the grain and flesh layers of the resultant leather could attain 130° and 136°.

Conformation of surface-decorating dextran chains affects the pharmacokinetics and biodistribution of doxorubicin-loaded nanoparticles

Recent reports showed that subtle modifications of nanoparticle surface properties induced dramatic changes of interactions with serum proteins. The present work was aimed to investigate the effect of the conformation of dextran chains decorating the surface of poly(alkylcyanoacrylate) (PACA) nanoparticles on the pharmacokinetic and biodistribution of a model drug associated with the nanoparticles. Doxorubicin was associated with PACA nanoparticles prepared by anionic emulsion polymerization (AEP) (Dox-AEP) and redox radical emulsion polymerization (RREP) (Dox-RREP). Nanoparticles and the free drug (f-Dox) were injected intravenously to rats to determine the pharmacokinetic and biodistribution of doxorubicin. Curves of the pharmacokinetics showed a rapid phase of distribution followed by a slower elimination phase. Pharmacokinetic parameters of the distribution phase determined for the Dox-RREP were significantly different from those of f-Dox and Dox-AEP, while no difference was observed in the elimination phase of the three formulations. Rats treated with Dox-RREP showed lower Dox concentrations in liver but higher concentrations in heart, lungs, and kidneys compared to those treated with the other formulations. Dox-RREP exhibited a new type of stealth behavior characterized by a short circulation time and a rapid distribution in highly vascularized organs bypassing the MPS. The difference in pharmacokinetic and biodistribution observed between the drugs formulated with the two types of nanoparticles was attributed to the difference in the conformation of the dextran chains stranded on the nanoparticle surface.

New route to 3-methacryloxypropyltrimethoxysilane-base organic–inorganic hybrid film

A series of poly(3-methacryloxypropyltrimethoxysilane)/waterborne polyurethane (PMPS/WPU) composite latexes and organic–inorganic hybrid films with PMPS contents of 0, 10, 20, 30, 40 and 50 wt.% were prepared via seeded emulsion polymerization initiated by AIBN and hydrolysis–condensation process of PMPS during the evaporation of water, respectively. WPU, that is anionic polyurethane emulsion, was synthesized using isophorone diisocyanate, polytetramethylene ether glycol, dimethylol propionic acid, 1,4-butanediol, and triethylamine. An investigation of transmission electron microscopy confirmed the core–shell morphology of the composite latex particle which was composed of a PMPS core and a polyurethane shell. A dynamic light scattering analysis showed that the average particle size distributed in the range of 42–134 nm. The proposed novel preparation method included the use of polyurethane as macromolecular emulsifier and steric stabilizer, control of (3-methacryloxypropyltrimethoxysilane) (MPS) content less than 50 wt.%, slow addition of MPS and application of AIBN ensured the preparation of a stable PMPS/WPU composite latex. Formed PMPS/WPU organic–inorganic hybrid film with high PMPS content via sol-gel process had uniform transparency at visible band because of less crystalline and phase separation between organic and inorganic phases.

Development of Functional Carbon Nanotubes -Asphalt Composites

The purpose of this study is to prepare asphalt composites containing CNTs and to elucidate the characteristic properties of CNTs-dispersed asphalt composites. In the present study, such composites were prepared using several types of asphalt emulsions as a binder. As a result, both nonionic and anionic emulsions kept dispersed state, when combined with as-prepared CNTs. However, cationic emulsions failed to keep dispersed state. After several additional systematic experiments, it was found that cationic emulsion successfully retained an adequate dispersion state, when as-prepared CNTs were treated with acid solution and the following incremental addition of the pretreated CNTs. The three types of CNTs-asphalt composites demonstrated higher performances in both penetration and microwave-absorption tests than asphalt composites including carbon black powder instead of CNTs, when the mass percentage of all carbon materials was the same

Atmospheric-air plasma enhances coating of different lubricating agents on polyester fiber

This research work involves the plasma treatment of polyethylene terephthalate fiber to improve performance of various ionic lubricating agents. To do this, polyester fabric was pre-scoured with detergent, treated with atmospheric-air plasma and then coated with anionic, cationic and nonionic emulsions. Chemical and physical properties of samples were investigated by the use of Fourier transform infrared spectroscopy (FTIR), bending lengths (BL), wrinkle recovery angles (WRA), fiber friction coefficient analysis (FFCA), moisture absorbency (MA), scanning electron microscopy (SEM) and reflectance spectroscopy (RS). Study on chemical properties of fibers revealed that the plasma pretreatment modifies the surface of fibers and increases the reactivity of substrate toward various ionic emulsions. Physical properties of textiles indicated that the combination of plasma and emulsion treatments on polyester can improve crease resistant, drapeability and water repellency due to uniform coating of various emulsions on surface of textiles.

Study on the rheological properties of fresh cement asphalt paste

The rheological properties of fresh cement asphalt paste (CA paste) were investigated, in which influencing factors such as type of asphalt emulsion, temperature, and time were discussed. CA pastes with two types of asphalt emulsions and varied asphalt contents were prepared at 0, 20 and 40 °C. The initial yield stress and its development over shelf time were tested to characterize the rheological properties of the pastes. The measurement of semi-adiabatic temperature development during hydration and optical microscopic observation were carried out to determine the hydration kinetics and microstructure evolution of the pastes. Results indicate that the initial flowability and flowability retention over shelf time of the pastes visibly improve because of the plasticizing effect of the asphalt emulsion and its retardation effect on cement hydration. The anionic asphalt emulsion is more effective than the cationic type because the former exhibits favorable adsorption onto the surface of cement grains. The temperature sensitivity of the rheological properties of the CA paste depends on the type and content of asphalt emulsion. The effects of time and temperature on rheological behavior were integrated into the effect of cement hydration degree. A generalized model linking yield stress and relative hydration degree α′ was established. Experimental results show that yield stress increases in a roughly linear fashion with 1/(1− α′) for all tested CA pastes.

Laboratory studies to investigate the properties of CIR mixes containing steel slag as a substitute for virgin aggregates

This paper aims to evaluate the effectiveness of steel slag as a substitute for virgin aggregates on mechanical properties of cold mix recycling asphalt pavement. For this purpose, gradation requirements of two types of Reclaimed Asphalt Pavement (RAP) materials in Cold In Place Recycling (CIR) mixes were modified. Mixtures’ gradation requirements were satisfied by adding 20% and 10% of two types of new aggregates in accordance with Asphalt Institute CIR grading requirements. The results showed that the use of steel slag can enhance Marshall stability, resilient modulus, tensile strength, resistance to moisture damage and resistance to permanent deformation of CIR mixes. Use of anionic bitumen emulsion is recommended in preparing mixtures, because of its compatibility with them.

Anionic emulsion-directed synthesis of zeolite ZSM-5 with tunable morphology and Si/Al ratio

Zeolite ZSM-5 was synthesized for the first time in an anionic emulsion system composed of sodium dodecylbenzene sulfonate, pentanol, cyclohexane and zeolite synthesis mixture, and subsequently characterized by XRD, SEM, FTIR, TG and N2 adsorption techniques. It is found that altering emulsion composition and adding electrolyte can effectively change the morphologies and/or Si/Al ratios of the ZSM-5 samples. Besides the commonly seen coffin morphology, ZSM-5 particles with rare elliptic cylinder, column and ellipsoid morphologies are also obtained. Depending on the weight ratios of anionic surfactant and zeolite reaction mixture, the framework Si/Al ratios of ZSM-5 samples vary slightly. Investigations on the crystallization process further show the emulsion system can induce rapid crystallization by virtue of shortening the induction time. The ways that the emulsion system affects zeolite crystallization, framework Si/Al ratio and particle morphology are tentatively discussed.

Kinetics of structure build-up in self-bodied emulsions stabilized by mixed emulsifers.

Journal Article Kinetics of structure build-up in self-bodied emulsions stabilized by mixed emulsifiers Get access B W BARRY, B W BARRY School of Pharmacy, Portsmouth Polytechnic, Park Road, Portsmouth, PO1 2QQ, UK Search for other works by this author on: Oxford Academic Google Scholar G M SAUNDERS G M SAUNDERS School of Pharmacy, Portsmouth Polytechnic, Park Road, Portsmouth, PO1 2QQ, UK Search for other works by this author on: Oxford Academic Google Scholar Journal of Pharmacy and Pharmacology, Volume 23, Issue Supplement_1, December 1971, Page 240S, https://doi.org/10.1111/j.2042-7158.1971.tb08827.x Published: 12 April 2011

Influence of acetazolamide loading on the (in vitro) performances of non-phospholipid-based cationic nanosized emulsion in comparison with phospholipid-based anionic and neutral-charged nanosized emulsions

Context: Acetazolamide (ACZM)-loaded anionic, cationic, and neutral-charged oil-in-water nanosized emulsions were prepared and compared with their mean droplet diameter, surface charge, entrapment efficiency, freeze–thaw cycling stability, in vitro drug release, and transcorneal permeation.Objective: The present study aims to determine the influence of ACZM loading on the performances of non-phospholipid-based cationic nanosized emulsion in comparison with phospholipid-based anionic and neutral-charged nanosized emulsions.Results and discussion: Regardless of charges, all of these emulsions exhibited a nanometer range mean particle diameter (240–443 nm) following autoclave sterilization. While the anionic and cationic emulsions did show high negative (−36.9 mV) and positive zeta potential (+41.4 mV) values, the neutral-charged emulsion did not. Presence of cryoprotectants (5% w/w sucrose + 5% w/w sorbitol) improved the stability of cationic emulsion to droplet aggregation during freeze–thaw cycling. The in vitro release kinetic behavior of drug exchange with physiological anions present in the simulated tear solution appears to be complex and difficult to characterize using mathematical fitting model equations. Augmentation in drug permeation through goat cornea, in vitro, was noticed for cationic emulsion.Conclusion: ACZM-loaded cationic nanosized emulsion could be suitable for topical application into eye to elicit better therapeutic effect in comparison with its anionic and neutral-charged emulsions.

Cytotoxicity and cellular uptake of newly synthesized fucoidan-coated nanoparticles

The aim was to synthesize and characterize fucoidan-coated poly(isobutylcyanoacrylate) nanoparticles. The nanoparticles were prepared by anionic emulsion polymerization (AEP) and by redox radical emulsion polymerization (RREP) of isobutylcyanoacrylate using fucoidan as a new coating material. The nanoparticles were characterized, and their cytotoxicity was evaluated in vitro on J774 macrophage and NIH-3T3 fibroblast cell lines. Cellular uptake of labeled nanoparticles was investigated by confocal fluorescence microscopy. Results showed that both methods were suitable to prepare stable formulations of fucoidan-coated PIBCA nanoparticles. Stable dispersions of nanoparticles were obtained by AEP with up to 100% fucoidan as coating material. By the RREP method, stable suspensions of nanoparticles were obtained with only up to 25% fucoidan in a blend of polysaccharide composed of dextran and fucoidan. The zeta potential of fucoidan-coated nanoparticles was decreased depending on the percentage of fucoidan. It reached the value of −44 mV for nanoparticles prepared by AEP with 100% of fucoidan. Nanoparticles made by AEP appeared more than four times more cytotoxic (IC 50 below 2 μg/mL) on macrophages J774 than nanoparticles made by RREP (IC 50 above 9 μg/mL). In contrast, no significant difference in cytotoxicity was highlighted by incubation of the nanoparticles with a fibroblast cell line. On fibroblasts, both types of nanoparticles showed similar cytotoxicity. Confocal fluorescence microscopy observations revealed that all types of nanoparticles were taken up by both cell lines. The distribution of the fluorescence in the cells varied greatly with the type of nanoparticles.

Reactive maleic anhydride polyolefins (MAPOs) in oriented strand board. Part 2: Influence on physical and mechanical properties

Abstract The use of reactive polyolefin and phenol formaldehyde (PF) resin blends to improve the moisture durability of oriented strand composite (OSC) panels was investigated. Test panels were hot pressed with adhesive blends consisting of varying proportions of PF and maleic anhydride polypropylene (MAPP) anionic emulsion, and their physical and mechanical properties were evaluated. The addition of MAPP did not significantly affect the modulus of elasticity (MOE) of the panels, but reduced the modulus of rupture in bending (MOR) for 12% moisture content (MC) and 24-h soak specimens. An increase in PF content significantly improved the MOE and MOR of specimens subjected to the environment. Adding MAPP reduced internal bond strength, particularly at higher PF levels. The addition of MAPP and raising PF levels significantly reduced water absorption and thickness swelling of the panels. At higher MAPP levels, the water vapor transmission in OSC as well as the permeance of the material, was reduced. Composite board equilibrated to lower MC with increasing MAPP content in the resin blend. The results indicate that increasing the PF content is the most effective method of improving both moisture resistance and the mechanical properties of OSC; addition of MAPP improves the moisture resistance of the panels, but significantly reduces their mechanical properties.

Reactive maleic anhydride polyolefins (MAPOs) in oriented strand board. Part 1: Dynamic thermomechanical properties of phenol formaldehyde resins blended with two MAPOs

Abstract A mechanism to improve the toughness of phenol formaldehyde (PF) resin for wood composites is investigated. It is hypothesized that addition of maleic anhydride polyolefins (MAPO), namely maleic anhydride polypropylene (MAPP) and maleic anhydride polyethylene (MAPE), to PF resin will toughen it owing to phase separation between the resin and MAPO. Dynamic mechanical analysis of resin with a low level of MAPP (0.5%) showed an improvement in the storage modulus (E′) or stiffness of the resin system during curing. Similarly, the damping property, tanδ, examined at three discrete temperatures, improved with blends of low levels of MAPP (0.5%). The fracture energies (GIc and GIa) at 12% moisture content were increased with the addition of MAPP at lower proportions (1.5%, 3%, and 4.5%); whereas the addition of MAPE showed a reduction in fracture energies, although not significant, particularly at lower levels. After 24 h soaking, specimens with MAPP showed significant improvements in GIc only at the 3% level; however, addition of MAPE resulted in a reduction of both the fracture energies. On the basis of these results, PF resin was blended with MAPP anionic emulsion for fabrication of oriented strand composites (OSC) test boards in Part 2 of the study.

Doxorubicin loading and in vitro release from poly(alkylcyanoacrylate) nanoparticles produced by redox radical emulsion polymerization

AbstractThe aim of this work was to explore the capacity to load an anticancer agent Doxorubicin (Dox) on new poly(alkylcyanoacrylate) (PACA) nanoparticles prepared by redox radical emulsion polymerization (RREP). These nanoparticles present several advantages compared with the previously described PACA nanoparticles obtained by anionic emulsion polymerization (AEP). Their cytotoxicity was lower and because they do not activate the complement system, they are believed to behave like stealth nanoparticles after intravenous administration. Dox was incorporated during the preparation of the nanoparticles. However, the drug molecules were degraded by cerium IV, which is a strong oxidant agent. To avoid drug degradation, Dox must be loaded by adsorption on preformed nanoparticles. Optimal loading capacity was deduced from a Scatchard's analysis of the Dox adsorption pattern. The loading performance [Loading efficiency (LE) 74%, Loading content (LC) 3.7%], the Dox release and the amount of Dox retained by the new nanoparticles 75% were similar to those of the already well described PACA nanoparticles obtained by AEP (LE 79% and LC 4.2%, drug retention capacity 75%). It can be concluded that the loading and releasing properties make the new nanoparticles an interesting carrier candidate for the in vivo delivery of Dox. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011

ANIONIC EMULSION-MEDIATED SYNTHESIS OF ZEOLITE BETA

Well-crystallized zeolite beta is first synthesized in the anionic emulsion systems of cyclohexane/sodium dodecylbenzenesulfonate(SDBS)/pentanol/zeolite synthesis mixture. Beta materials are then characterized by XRD, SEM, and N 2-adsorption techniques. Compared to beta samples grown using the same synthesis mixture in the absence of the anionic emulsion, the as-synthesized beta presents uniform and well-defined larger crystals. Interestingly, N 2-adsorption results show that such beta sample possesses both ordered mesopores at 3.9 nm and macropores centered at 60.5 nm. These pores combined with the intricate micropores of the Beta crystal comprise the hierarchical porosity. The hierarchical pore-structured zeolite beta may have potential catalysis application in reactions involving large molecules. Additionally, control experiments are also performed to ascertain the effects of the individual emulsion components. Further synthesis study finds the transformation of zeolite beta to ZSM-5 through increasing oil contents, crystallization temperature and time.

Evaluation of Longitudinal Joint Construction Techniques for Asphalt Pavements in Tennessee

Longitudinal joints between lanes of hot-mix asphalt (HMA) pavements are commonly susceptible to moisture damage and other failures. In 2006, the Tennessee Department of Transportation (TDOT) identified longitudinal joint failure as one of the major distresses for local HMA pavements. It was determined necessary to evaluate available practices and technologies to reduce longitudinal joint failure. This paper presents the results from a field project in Tennessee constructed with seven different longitudinal joint construction techniques. These techniques could be divided into three major categories: joint adhesives including an anionic emulsion and a polymerized emulsion commonly used by the TDOT, a hot-applied high-polymer rubber, and a high-polymer emulsion; joint sealers including a polymerized maltene emulsion and a polymerized agricultural oil; and infrared joint heater. Laboratory tests were conducted on the field cores taken from the test sections constructed with these techniques. Based on the different mechanisms of these techniques, the following laboratory tests were employed: air void content, permeability, indirect tensile (IDT) strength, and water absorption tests. Field cores were also scanned with the X-ray computed tomography to investigate the effect of infrared heating on air void distribution. The test results showed general consistency in the joint quality; i.e., the lower the air void content, the lower the permeability and the higher the IDT strength. The infrared heater exhibited the best effectiveness in improving joint quality among all the joint construction techniques used in this study.

Study on the hardening mechanism of cement asphalt binder

The hydration and hardening mechanism of cement asphalt binder (CAB) was studied. The early hydration process, hydration products and paste microstructure of CAB made by Portland cement and anionic asphalt emulsion were investigated by calorimetry, X-ray diffraction, and environmental scanning electron microscopy. The early hydration process of CAB can be characterized as 5 stages similar to those of Portland cement. There is no chemical reaction detected between cement and asphalt, hence no new hydration products other than those of Portland cement are produced. The hardening of CAB begins with the hydration of cement. When the hydration of cement comes into the acceleration period and its exothermic rate comes to the maximum, the coalescence of asphalt particles in asphalt emulsion is triggered. In the hardened system of CAB, it was found that the hydration products of cement form the skeleton and are covered by the continuous asphalt film. They formed an interpenetrating network system. The emulsifiers in the asphalt emulsion may retard the hydration process of cement.

Synthesis of zeolite NaY in anionic, cationic and nonionic emulsions

Zeolite NaY has been first synthesized respectively in the anionic, cationic and nonionic emulsions. The emulsion systems can accelerate zeolite NaY crystallization and in some cases retard the growth of impurity. Compared to the conventional zeolite NaY synthesized in the absence of emulsion, the emulsion-mediated NaY samples show different morphologies, larger surface areas and higher pore volumes depending on the charge nature of the surfactants involved. In particular, the NaY sample synthesized in the nonionic emulsion system presents a hierarchical pore structure with the highest BET surface area of 646.85 m 2 g −1. The increase of surface areas for the NaY products made in emulsion media is due to the removal of emulsion components occluded in the pore structures through calcination. These features of the NaY zeolites synthesized in emulsion media, such as various product morphologies and high surface areas, may bestow the materials unique catalytic properties in their potential applications.

ESTABILIDADE DE EMULSÕES FRENTE A DIFERENTES TÉCNICAS DE HOMOGENEIZAÇÃO E RESFRIAMENTO.

Na farmácia de manipulação, as emulsões são os veículos ideais para diversas aplicações cosméticas e farmacêuticas, pois reúnem qualidades estéticas e funcionais, como a solubilização de componentes hidro e lipofílicos. As emulsões precisam demonstrar estabilidade física sob as mais variadas condições, como as variações de temperatura e o estresse induzido pelas vibrações durante o transporte. Devem, também, manter a consistência adequada para conseguir boa sensação sobre a pele, espalhar-se e liberar ingredientes ativos. O estudo de estabilidade de produtos cosméticos fornece informações sobre o comportamento do produto, indicando seu grau de estabilidade em determinado intervalo de tempo, frente a condições ambientais a que possa ser submetido, desde a fabricação até o término do prazo de validade. O objetivo deste trabalho foi verificar a estabilidade e os caracteres organolépticos de emulsões, após o preparo das mesmas, utilizando diferentes técnicas de homogeneização e resfriamento. Para a realização dos testes de estabilidade foram utilizadas duas formulações, uma emulsão aniônica, o Creme Lanette® e uma emulsão não iônica, o Creme Polawax®. Após a pesagem das matérias-primas, aquecimento e mistura das fases, a homogeneização foi realizada de quatro maneiras diferentes, quanto à temperatura e velocidade de agitação, até atingir a temperatura de 40ºC. Depois de submetidos a testes de estabilidade, não foram verificadas diferenças significativas nas características dos cremes estudados, mediante as técnicas de homogeneização e resfriamento aplicados.

SYNTHESIS AND PROPERTIES OF WATERBORNE POLYURETHANES MODIFIED BY EPOXY RESIN

A series of anionic waterborne polyurethane emulsion modified by epoxy resin were successfully prepared by the reaction of polycaprolactone diols(CAPA),isophorone isocyanate(IPDI),hexamethylene-1,6-diisocyanate(HDI) and epoxy resin(E-44) as crosslinker.Solidified films of the waterborne polyurethane were prepared by casting emulsions on Teflon surfaces.Fourier transform infared spectrometer(FTIR) and thermogravimetry analysis(TGA) were used to characterize the structure of the polyurethane.The mechanical properties and water contact angle of the cast films were also measured.The surface roughness and surface morphology of the films of waterborne polyurethanes were observed by atomic force microscopy(AFM).The particle size and distribution of the resultant polymer emulsions was tested by the dynamic laser light scattering(DLLS).FTIR indicates that epoxy group and hydroxyl group of E-44 both reacted with the polyurethane prepolymer.TGA indicates that the crosslink of E44 with polyurethane increased thermal stability of the modified polyurethanes.It was found that the tensile strength of films of modified polyurethane increased and the elongation at break decreased with increasing E-44 content,the water contact angle increases with increasing w(E-44),the smoothness of solidified films of waterborne polyurethane decrease when modified by E-44,resulting in water repellence functions.DLLS showed that the particle size of emulsion increased with increasing w(E-44).In order to obtain stable polyurethane emulsions and solidified films of waterborne polyurethanes with improved mechanical properties,the proper w(E-44) is 10%.