Alkenyl Succinic Anhydride Research Articles

Hydrophobization of starch nanocrystals through esterification in green media

Starch nanocrystals (SNC) were successfully modified through esterification by using dodecenyl succinic anhydride (DDSA), 2-octen-1-ylsuccinic anhydride (OSA) and acetic anhydride (AA) in green media. The chemical modifications were confirmed using FT-IR. The esterification extent of the modified SNC was evaluated by degree of substitution (DS). The modifications imparted hydrophobic character to SNC so that the modified SNC could be dispersed in non-polar solvents such as chloroform, dichloromethane and toluene. It was found that the dispersibility of the modified SNC in non-polar solvents increased with increasing of DS and hydrophobicity of the group replacing the hydroxyl groups in starch. XRD analysis showed that the crystalline structure of SNC was preserved after the modifications.

Surface modification of cellulose nanowhiskers for application in thermosetting epoxy polymers

Cellulose nanowhiskers (CNWs) were chemically modified with dodecenyl succinic anhydride to obtain hydrophobic CNWs called DCNWs. Surface modification was confirmed by infrared spectroscopy, transmission electron microscopy, and X-ray diffraction. The surface substitution degree determined by X-ray photoelectron spectroscopy was 0.30. Nanocomposites were prepared by incorporating different amounts of DCNWs pre-dispersed in a small amount of acetone into an epoxy matrix. Scanning electron microscope demonstrated that DCNWs dispersed well in the epoxy matrix. A strong interaction was proved between the DCNWs and epoxy matrix, as results of which the nanocomposites exhibited an obvious increase in Tg by about 30 °C, simultaneous increases in tensile strength, Young’s modulus, and strain at break; and an improvement in the hydrothermal properties. Compared with the neat epoxy, the nanocomposite containing 3.5 wt% of DCNWs exhibited an increase in tensile strength by 82 %, Young’s modulus by 21 %, and a strain at break by 198 %.

Stability and efficiency improvement of ASA in internal sizing of cellulosic paper by using cationically modified cellulose nanocrystals

Alkenyl succinic anhydride (ASA) is a reactive sizing agent that can impart good water repellence to paper by decreasing the wettability of the cellulose fibers. However, ASA can undergo hydrolysis, which is detrimental to the ASA sizing efficiency. In order to improve the ASA emulsion stability and ASA sizing efficiency, we used cationically modified cellulose nanocrystals (CNCs) to stabilize the cationic starch-emulsified ASA. Transmission electron microscope observation revealed that ASA droplets were well shielded by both the cationic CNCs and cationic starch, which may be responsible for the improved stabilization of ASA. The Hercules size test sizing degree, contact angle and particle size measurements demonstrated that cationic CNCs–ASA sized paper exhibited improved results in comparison with the control (without cationic CNCs under otherwise the same conditions). Furthermore, the resulting cationic CNCs–ASA system can improve the tensile index and burst index of the sized paper.

Cytotoxicity and Antioxidant Activity of Beta vulgaris Extract Released from Grafted Carbon Nanotubes Based Nanocomposites

SummaryThis work deals with preparation and characterization of novel grafted multi‐walled carbon nanotubes (MWCNTs) with dodecenyl succinic anhydride (DSA) in presence of plant extract (Beta vulgaris) and hydroxyapatite nanoparticles (HA). Moreover, cytotoxicity and antioxidant activity of the prepared nanocomposites using Ehrlich ascites carcinoma cells (EACC) were examined and evaluated. The prepared nanocomposites were characterized using Fourier transform infrared spectroscopy (FTIR) and transmission electron microscope (TEM). In addition to the particle size and zeta potential were recorded. The grafting technique was significantly enhanced the nanotube dispersibility and long term stability in the aqueous solution. The results indicated that the conjugation between B. vulgaris extract, HA nanoparticles and functionalized MWCNTs exhibited great antioxidant activity through the scavenging of the free radicals using DPPH assay. Also, the encapsulated B. vulgaris extract within the grafted MWCNTs based nanocomposites exhibited acceptable effect on the viability of EACC in compared with the standard (Vincrestine®). In other words, these novel functionalized MWCNTs based nanocomposites could be used as antioxidant and antitumor agents in the future after further studies.

Synthesis, characterization and emulsification properties of dodecenyl succinic anhydride derivatives of gum Arabic

Gum Arabic, GA, has been chemically modified using dodecenyl succinic anhydride (DDSA) in aqueous solution and the products have been characterized and their solution and emulsification properties evaluated. FTIR was used to confirm that derivatisation had occurred and the hydrophobe incorporation and reaction efficiency was determined by a simple titration method. The derivatives, DGA5 and DGA10 were found to contain 5 and 10 %w/w DDSA respectively. Surface tension and dye solubilisation measurements demonstrated that the modified GA samples aggregated in solution at a specific concentration, referred to as the critical aggregation concentration, CAC. The value of the CAC was found to be a function of the degree of substitution and values of 0.1% and 0.04% were obtained for DGA5 and DGA10 respectively. The emulsification properties of the polymers were assessed by determination of the droplet size as a function of polymer concentration and time using laser diffraction. The droplet size decreased for all samples as the polymer concentration increased but the minimum droplet size obtained increased in the order DGA10 < DGA5 < GA indicating enhanced emulsification efficiency with increasing hydrophobe content. The effect of ageing on emulsion stability was assessed and the droplet size of emulsions prepared with GA and DGA5 increased with time but remained constant for samples prepared with DGA10. Emulsion creaming was followed using the Turbiscan and it was noted that DGA5 and DGA10 were much more effective than GA at reducing creaming. The results have demonstrated that the modified gum Arabic samples have potential application for microencapsulation.

Formation of Particle Coated Fusiform Droplets via Lowering Interface Tension with Polyaluminum Sulfate

It was found that the interface tension between water and alkenyl succinic anhydride (ASA) was significantly reduced by polyaluminum sulfate (PAS), increased considerably though by TiO2 nanoparticle. PAS with basicity of 0.75 (PAS-0.75) reduced the interface tension to a larger extent than PAS with basicity of 0.3 (PAS-0.3). By reducing interface tension with PAS-0.75, ASA-in-water emulsion bearing fusiform geometries was constructed. The emulsion stabilized by PAS-0.3 and TiO2 nanoparticle bore spherical shapes with the exception when mass fraction of TiO2 nanoparticle was low, in which case fused nonspherical drops were formed. Forming nonspherical emulsion crucially depends on ASA-water interface tension, where a critical interface tension was identified to be 0.6–0.7 mN/m. The fusiform geometries were transformed into spherical shapes when interface tension was higher than 0.7 mN/m. Both the lowering mechanism of the interface tension and the formation mechanism of the fusiform emulsion were proposed.

Effect of Surface Energy on Dispersion and Mechanical Properties of Polymer/Nanocrystalline Cellulose Nanocomposites

Dispersion quality and polymer-filler interaction are important factors in determining the final properties of polymer nanocomposites. Surface energy of nanocrystalline cellulose (NCC) and some polymers (polypropylene, PP, and polylactic acid, PLA) was measured at room and high temperatures. NCC had higher polarity and surface energy than PP and PLA at room temperature but had a lower surface energy at higher temperatures. The effect of surface modification with alkenyl succinic anhydride (ASA) on NCC surface energy at room and high temperature was studied. Total surface energy of NCC was lowered after surface modification. Thermodynamic work of adhesion for PP/NCC and PLA/NCC was lowered by NCC surface modification. A thermodynamic analysis is proposed to estimate the dispersion energy, based on surface energy measurements at room and high temperatures. Also, a dispersion factor is defined to provide a quantitative indication of the dispersibility of nanoparticles in a polymer matrix under various conditions. The required dispersion energy was reduced by lowering the interfacial tension. On the other hand, it increased as the quality of NCC dispersion (i.e., the nanoparticle surface area) in the system was improved. Surface modification of NCC with ASA had a negative effect on the compatibility between NCC and PLA, whereas it had a positive influence on compatibility between PP and NCC.

Stabilization of ASA-in-water emulsions by Laponite modified with alanine

Alkenyl succinic anhydride (ASA) is an oily paper sizing agent that is generally introduced into the paper manufacturing system as an ASA-in-water emulsion. In this paper, ASA-in-water emulsions are prepared by homogenizing the mixture of ASA and aqueous dispersion of Laponite modified with alanine. The modification of Laponite with alanine reduces the emulsion droplet size, and enhances the emulsion stability against coalescence due to lowering the interfacial tension between ASA and water containing Laponite and improving the affinity of Laponite particles toward ASA. Infrared spectrum analysis indicates that the adsorption of alanine on the Laponite particles retards the hydrolysis of ASA when the alanine-modified particles are employed to stabilize ASA emulsions. Meanwhile, the sizing efficiency of the as-prepared ASA emulsion is also improved by the modification of Laponite with alanine, and more dependent on emulsion droplet size than on the hydrolysis of ASA.

The Impact of Synthesis Conditions on the Structure and Properties of Di-(Stearylamidoethyl) Epoxypropyl Ammonium Chloride

Both alkylketene dimer (AKD) and alkenyl succinic anhydride (ASA) are widely used neutral papermaking sizing agents. However, AKD has the issue of sizing hysteresis, while ASA requires on-site emulsification. In addition, both reagents are readily hydrolyzed. Di-(stearylamidoethyl) epoxypropyl ammonium chloride (DSEAC) has been applied as a fabric softener, but it is a potential sizing agent which leads to good sizing without sizing hysteresis. It could be synthesized by a two-step process starting from stearic acid and diethylenetriamine. During the process, the stearamide structure obtained from the first step plays a key role in the second process as well as sizing. This paper focuses on the impact of the synthetic process of the first step on the structure and sizing properties of DSEAC. Single factor experimental results demonstrated that the optimal temperature should be 160 °C while the optimal reaction time should be less than 3.5 hours. Orthogonal analysis experiments indicated that the optimal synthetic process was maintaining 100 °C for 30 min, and then increasing the temperature to 160 °C for 3.5 hours. Dosages of the catalysis and antioxidant were 0.5% and 0.6% of stearic acid, respectively.

Preparation and Sizing Application of ASA\Liquid Paraffin Stabilized by Grafted Montmorillonite

Alkenyl succinic anhydride (ASA) is widely used to hydrophobize paper and paper board in papermaking industry. Montmorillonite (MMT) particles modified by trifunctional silylating agent were used as particulate emulsifier to prepare binary mixed sizing agent. It was found that stable ASA\liquid paraffin Pickering emulsions can be prepared by using grafted-MMT particles and the optimal dosage of LP oil was 50 vol.%. The ASALP Pickering emulsions exhibited some kinds of a solidlike viscoelastic behavior, which can be explained by the particulate network formed by grafted-MMT particles in the emulsion. Addition of LP oil not only improved the stability of ASA emulsions stabilized by particulate emulsifier, but also significantly promoted the internal paper sizing performance of ASA.

Using urea to improve stability, sizing performance and hydrolysis resistance of ASA emulsion stabilized by Laponite

As a paper sizing agent, alkenyl succinic anhydride (ASA) emulsion is generally stabilized by cationic starch or synthetic polymer. In this paper, Laponite and urea were employed as particle stabilizer and the modifier of Laponite particle, respectively, to stabilize the ASA emulsion. It is founded that the presence of urea enhances the stability of ASA emulsion, reduces the emulsion droplet size, resulting in improved sizing performance of the ASA emulsion. ASA emulsion with smallest droplet size and best sizing performance on BCTMP is obtained at the urea dosage of 50wt% based on Laponite. The sizing test of ASA emulsion and the infrared spectrum analysis of ASA substances separated from ASA emulsions with different storage time indicate that the introduction of urea in emulsification process can restrain the hydrolytic action of ASA effectively and sustain the sizing performance of ASA emulsion even two hours after its preparation. This is a possible way to solve the problem that paper mills have always encountered: the too rapid hydrolysis of ASA emulsion.

Preparation and evaluation of hydrophobically modified core shell calcium carbonate structure by different capping agents

Abstract Surface modification of precipitated calcium carbonate particles in a planetary ball mill using different dispersants such as stearic acid, oleic acid, palmitic acid, salicylic acid, oleyl amine, DDSA (dodecenyl succinic anhydride), ODSA (octadecenyl succinic anhydride), TPSA (tetra propenyl succinic anhydride) as modification agent was done in order to find out the potential of dispersant in surface modification and for making dispersion in hydrocarbon oil was investigated. Different dispersants were ball milled keeping all the parameters for processing (milling) like—milling time, ball ratios, sample dosage and milling constant. The physical properties of the hydrophobically modified calcium carbonate were measured; the particle size and morphology of the resulting samples were characterized by transmission electron microscopy (TEM) and X-ray diffraction (XRD). The surface coating thickness was also estimated by geometric calculation using results of TEM and TGA considering the formation of core shell structure.

Phase inversion of TiO2 nanoparticle stabilized emulsions of alkenyl succinic anhydride

Alkenyl succinic anhydride (ASA) is a viscous polar oil, typically used as a paper sizing agent after being emulsified. ASA and water emulsions stabilized by TiO2 nanoparticles were prepared by adding the aqueous phase to the oil phase. Catastrophic phase inversion from w/o to o/w or w/o/w has been investigated by monitoring the variation of emulsion conductivity with water mass fraction at different homogenization speeds, initial particle locations and particle concentrations. When initially dispersed in water, TiO2 nanoparticles carry positive charge and interact with hydrolyzed ASA at the water–ASA interface. The particles are thus hydrophobically modified, resulting in phase inversion from w/o to w/o/w at higher water mass fraction, while for particles originating in ASA, the phase inverts from w/o to o/w at a lower water mass fraction. Higher homogenization speed and lower particle concentration induce phase inversion at lower water mass fractions. In addition, variations in the phase inversion point caused by the homogenization speed and particle concentration are magnified when the particles originate in water. Similar to non-ionic surfactant-stabilized emulsions prepared by a catastrophic emulsification process, the particle-stabilized emulsions containing ASA exhibit a diminished drop size when approaching the water mass fraction at which phase inversion occurs. Emulsions with the particles initially dispersed in ASA have a slightly smaller drop size than those with particles initially dispersed in water. In addition, the drop size near the phase inversion point did not obviously change with particle concentration.

Hydrolysis behaviour of crosslinked poly(ester anhydride) networks prepared from functionalised poly(ε-caprolactone) precursors

Biodegradable poly(ester anhydride) networks based on functionalised poly(ε-caprolactone) precursors with different hydrophobicities, molecular weights and architectures were synthesised. Networks that were prepared from the star-shaped precursors clearly showed higher gel contents and crosslinking densities than the networks that were prepared from the linear precursors. Functionalising with different alkenylsuccinic anhydrides and/or varying the molecular weight of the precursor, the thermal properties, surface hydrophobicity and erosion of the crosslinked networks were widely tailored. The dissolution behaviour of the networks changed dramatically as the molecular weight of the precursor increased from 2000 to 4000g/mol or the alkenyl chain of the alkenylsuccinic anhydride increased from 8 to 18 carbons. The networks that were prepared from the lower molecular weight precursors, without an alkenyl chain or with an 8 carbon alkenyl chain, lost their mass in a few days, whereas the networks that were prepared from higher molecular weight precursors or contained a hydrophobic 18 carbon alkenyl chain did not show any mass loss over a period of 8weeks.

Novel Polymerizable Nonionic Surfactants (Surfmers) Corporate with Alkenylsuccinic Anhydride: Synthesis, Surface, and Thermodynamic Properties

In this article, nine polymerizable surfactants (surfmers) were prepared with terminal acrylate group on the hydrophilic moiety. The prepared surfmers were classified into three groups according to hydrophobic chain lengths; the first group (group I) was single-tailed with different hydrophobic chain lengths, the second group (group II) was asymmetric double-tailed, one of them was dodecenyl and the other is octyl or tetradecyl or octadecyl from fatty alcohols, and the third group (group III) is symmetric double-tailed. The chemical structures of the prepared nonionic surfmers were confirmed by mass spectra, elemental analysis, acid value titration, and FTIR and 1H NMR spectroscopy. The surface and thermodynamic parameters of the prepared surfmers were determined at 25°C including, surface tension (γ) and effectiveness, maximum surface excess (Γmax) and minimum surface area (Amin). Also, the standard free energy of micellization and adsorption were recorded. The results show that the surface and thermodynamic parameters of the prepared surfmers were sensitive to the discrepancy of surfmer tail length and their expected shape on the interface.

Using cationic polymers to improve alkenyl succinic anhydride (ASA) sizing efficiency in high-yield pulp containing furnish

High-yield pulp (HYP) such as bleached chemi-thermo-mechanical pulp (BCTMP) from aspen wood, is now being used in the production of high-quality fine papers, and this is particularly true in China. In this study, the effect of using cationic polymers such as poly-aluminum chloride (PAC), polyethylenimine (PEI), cationic polyacrylamide (CPAM), and poly-(diallyldimethylammonium chloride) (PDADMAC) on Alkenyl Succinic Anhydride (ASA) sizing efficiency in HYP-containing pulp furnish was investigated. The results showed that the addition of only ASA emulsion to the HYP-containing furnish, without any cationic additives, did not yield an appreciable degree of sizing in the paper sheet. PAC (or alum) could improve the ASA sizing efficiency. PEI, PDADMAC, CPAM, and NaHCO3 all improved ASA sizing efficiency in the presence of PAC. The charge density of PEI was important for improving the ASA sizing performance. Also, the sequence of adding the cationic polymer affected the ASA sizing performance.

Oil Spills Abatement: Factors Affecting Oil Uptake by Cellulosic Fibers

Wood-derived cellulosic fibers prepared in different ways were successfully employed to absorb simulated crude oil, demonstrating their possible use as absorbents in the case of oil spills. When dry fibers were used, the highest sorption capacity (six parts of oil per unit mass of fiber) was shown by bleached softwood kraft fibers, compared to hardwood bleached kraft and softwood chemithermomechanical pulp(CTMP) fibers. Increased refining of CTMP fibers decreased their oil uptake capacity. When the fibers were soaked in water before exposure to the oil, the ability of the unmodified kraft fibers to sorb oil was markedly reduced, whereas the wet CTMP fibers were generally more effective than the wet kraft fibers. Predeposition of lignin onto the surfaces of the bleached kraft fibers improved their ability to take up oil when wet. Superior ability to sorb oil in the wet state was achieved by pretreating the kraft fibers with a hydrophobic sizing agent, alkenylsuccinic anhydride (ASA). Contact angle tests on a model cellulose surface showed that some of the sorption results onto wetted fibers could be attributed to the more hydrophobic nature of the fibers after treatment with either lignin or ASA.

Synthesis of alkylated potato starch derivatives and their potential in the aqueous solubilization of benzo[a]pyrene

For the development of renewable bioproducts able to solubilize organic persistent pollutant such as benzo[a]pyrene (BaP), modified potato starch was synthesized by alkylation. The addition of alkyl chains was performed with three different alkylation agents: epoxyalkane, alkenyl succinic anhydride and 1,4-butane sultone. Twelve alkylated starches were obtained with different molar substitutions (MS) and various alkyl chain lengths (to three carbons up to sixteen). The chemical structural characteristics were investigated by methods of 1H NMR and FTIR. In comparison with the native starch, the ether modified starches showed in general an enhancement of their aqueous solubility whereas the ester modified starches stimulated the BaP aqueous solubilization. Indeed, the compounds P6 and P12, which increased 40-fold the BaP aqueous concentration, present high surfactant properties.

Effects of starch alkenylsuccinylation on the grafting efficiency, paste viscosity, and film properties of alkenylsuccinylated starch‐g‐poly(acrylic acid)

AbstractCommercial cornstarch was alkenylsuccinylated with alkenylsuccinic anhydride to different degrees of substitution (DS) and then the products were graft‐copolymerized with acrylic acid for investigating the effects of starch alkenylsuccinylation on the graft copolymerization with vinyl monomer, as well as on paste viscosity and film properties of alkenylsuccinylated starch‐g‐poly(acrylic acid) (ASS‐g‐PAA). The number of carbon atom of alkenyl in alkenylsuccinates considered was 8 and 12, corresponding to octenylsuccinylation and dodecenylsuccinylation of starch, respectively. The graft copolymerization was accessed by grafting efficiency, grafting ratio, and conversion of monomer to polymer, and the film properties of ASS‐g‐PAA considered included tensile strength, breaking elongation, and work‐to‐break. Experimental results demonstrated that the alkenylsuccinylation showed marked effects on the copolymerization, paste viscosity, and film properties. It resulted in increased grafting efficiency, stable paste viscosity, and strong starch film. Carbon‐chain length of the alkenyl and DS value of the alkenylsuccinates also exhibited evident effects on the copolymerization and film properties. Octenylsuccinylation of starch before the copolymerization was superior to dodecenylsuccinylation in improving the efficiency and film properties. Low levels of octenylsuccinylation could be utilized to increase the efficiency of the copolymerization and improve the properties of starch film.

SUBSTITUTION OF HIGH-YIELD-PULP FOR HARDWOOD BLEACHED KRAFT PULP IN PAPER PRODUCTION AND ITS EFFECT ON ALKENYL SUCCINIC ANHYDRIDE SIZING

In recent years there has been an increasing interest in using high-yield pulp (HYP) as a partial replacement for hardwood bleached kraft pulp (HWBKP) in the production of high-quality fine papers as a cost-effective way of improving the product performance. This study investigated the substitution of HYP for HWBKP and its effect on the Alkenyl Succinic Anhydride (ASA) sizing performance. The results showed that the substitution of an aspen HYP for HWBKP can increase the ASA sizing performance at a HYP substitution as high as 15 to 20%. The ASA addition sequence has an influence on the ASA sizing performance and first adding ASA to the HYP followed by mixing with kraft pulps was the preferred method. Using precipitated calcium carbonate (PCC) as a paper filler at a dosage of less than 20% can increase the ASA sizing performance due to the contribution of the calcium soap of the hydrolysed ASA. A PCC dosage greater than 20% resulted in a negative impact on the sizing performance. It was also found that different PCC loading sequences can also affect the ASA sizing performance.