Lauroyl Chloride Research Articles

Experimental and theoretical insight into the use of maleic anhydride copolymer and modified sulfamic acid for removing oilfield blockage

In the process of oil production, the problem of oilfield production decline due to blockage is becoming more and more serious. To improve the exploitation efficiency of traditional fuel, it is very important to remove the blockage and inhibit the formation of the blockage. In this study, the primary constituents of the blockages in this oilfield were identified as asphaltene (organic blockage) and calcium carbonate (CaCO3, inorganic blockage). To address these blockages, maleic anhydride copolymer (MAC-1, MAC-2, and MAC-3) with different chain lengths were polymerized by maleic anhydride and allyl polyoxyethylene ether, which were used to disperse organic blockages. Additionally, modified sulfamic acid (MSA-1, MSA-2, and MSA-3) with different chain lengths were synthesized by sulfamic acid, polyethylene glycol, and lauroyl chloride, which were used to dissolve inorganic blockages. The efficacy of these agents in terms of blockage removal, scale inhibition capability, corrosion rate, and compatibility with formation water were comprehensively evaluated. Results showed that MAC-2, which possesses a moderate chain length, and MSA-1, which has a shorter chain length, demonstrated an optimal synergistic effect on blockage dissolution at concentrations of 4 wt% for MAC-2 and 5 wt% for MSA-1. The dissolution rate of this combination was 81.18 %, with a scale inhibition rate of 95.7 %. The corrosion rate increased with temperature, and the agents maintained good compatibility with the formation water. To elucidate the mechanism underlying the effectiveness of MAC, the interaction between MAC and asphaltene was simulated by molecular dynamics (MD). These simulations indicated that MAC-2 and asphaltene exhibit the highest interaction energy (-64.2618 kcal/mol). Furthermore, we investigated the dissolution kinetics of CaCO3 in MSA solutions and determined that the reaction between MSA and CaCO3 was first-order, with a reaction rate constant of 1.6 × 10−2 min−1. The insights gained from this study offer a valuable experimental and theoretical foundation for enhancing productivity in similar oilfields.

The α-Substituent effect of amino acids on performance of N-Lauroyl amino acid surfactants

Synthetic soaps of N-lauroyl amino acid surfactants (LAAS) were synthesized in this work from lauroyl chloride and five typical amino acids with different α-substituents including α-alanine or α-aminobutyric acid with a hydrophobic α-substituent, serine with a hydrophilic α-substituent, and glutamic acid with an ionizable α-substituent normalized to Gly with the simplest α-amino acid structure to compare the α-substituent effect on physicochemical properties and application performance of LAAS. The surface adsorption, micellization, foamability, emulsification, wettability, and detergency of these LAAS were investigated. Experimental results indicate that the hydrophobic α-substituent of amino acid can reduce both critical micelle temperature and critical micelle concentration of LAAS, promote surface adsorption and general performance with respect to foamability, emulsifying power, and wetting power, while the hydrophilic α-substituent is on the contrary. Moreover, sodium lauroyl glycinate demonstrates the best overall detergency among five LAAS, and is the solely one performing better detergency than sodium laurate for all three standard soiled swatches, indicating the potential for detergents.

Development of novel pyrimidine nucleoside analogs as potential anticancer agents: Synthesis, characterization, and In-vitro evaluation against pancreatic cancer

The present study proposed modification of 5-FU by conjugation with an acyl chloride and a 5-membered heterocyclic ring to improve its in-vitro cytotoxicity and metabolic stability. XYZ-I-71 and XYZ-I-73 were synthesized by introducing a tetrahydrofuran ring on 5-fluorocytosine (a precursor of 5-FU) and conjugation with octanoyl chloride and lauroyl chloride, respectively. The structure of the synthesized compounds was validated using NMR and micro-elemental analysis. The antiproliferative activity of the analogs was determined against MiaPaCa-2, PANC-1, and BxPC-3 pancreatic cancer cells. The analog's stability in human liver microsomes was quantified by HPLC. We found that the XYZ-I-73 (IC50 3.6 ± 0.4 μM) analog was most effective against MiaPaCa-2 cells compared to XYZ-I-71(IC50 12.3 ± 1.7 μM), GemHCl (IC50 24.2 ± 1.3 μM), Irinotecan (IC50 10.1 ± 1.5 μM) and 5-FU (IC50 13.2 ± 1.1 μM). The antiproliferative effects of this analog in Miapaca-2 cells is evident based on it having a 7-fold,3-fold, and 4-fold increased cytotoxic effect over Gem-HCl, Irinotecan, and 5-FU, respectively. On the other hand, XYZ-I-71 exhibited a 2-fold increased cytotoxic effect over Gem-HCl but a comparable cytotoxic effect to 5-FU and Irinotecan in MiaPaCa-2 cells. A similar trend of higher XYZ-I-73 inhibition was observed in PANC-1 and BxPC-3 cultures. For 48-h MiaPaCa-2 cell migration studies, XYZ-I-73 (5 μM) significantly reduced migration (# of migrated cells, 168 ± 2.9), followed by XYZ-I-71(315±2.1), Gem-HCl (762±3.1) and 5-FU (710 ± 3.2). PARP absorbance studies demonstrated significant inhibition of PARP expression of XYZ-I-73 treated cells compared to 5-FU, GemHCl, and XYZ-I-71. Further, BAX and p53 expressions were significantly increased in cells treated with XYZ-I-73 compared to 5-FU, GemHCl, and XYZ-I-71. In-vitro, metabolic stability studies showed that 80 ± 5.9% of XYZ-I-71 and XYZ-I-73 remained intact after 2 h exposure in liver microsomal solution compared to 5-FU. The XYZ-I-73 analog demonstrated a remarkable cytotoxic effect and improved in-vitro metabolic stability over the selected standard drugs and may have potential anticancer activity against pancreatic cancer.

Abstract 1825: Synthesis and biological evaluation of novel 5-FU analogs against pancreatic cancer

Abstract Purpose: 5-Fluorouracil (5-FU) is one of the standard chemotherapy drugs used to treat pancreatic cancer. However, treatment only extends survival modestly, and disease recurrence is typical due to systemic instability, drug resistance, severe adverse effects, and limited benefits in patients with locally advanced tumors. These shortcomings have necessitated new strategies to develop safer and more effective anticancer agents. The study’s objective was to synthesize, characterize, and evaluate the cytotoxic effects of novel 5-FU analogs in pancreatic cancer cells. Methods: The analogs, XYZ-I-71 and XYZ-I-73, were synthesized by introducing a tetrahydrofuran ring on 5-fluorocytosine (a precursor of 5-FU) and conjugation with octanoyl chloride and lauroyl chloride, respectively. They were characterized by NMR, HPLC, micro-elemental analysis, and mass spectrometry. Cytotoxicity and cell migration studies were performed to determine the effectiveness of the analogs against MiaPaCa-2, PANC-1, and BxPC-3 pancreatic cancer cells. PARP apoptosis study was conducted in MiaPaca-2 cells using the analogs and 5-FU. The metabolic stability of analogs was determined by using human liver microsomes and quantified by HPLC. Results: Analysis of the 1H-NMR spectra displayed amide bonds at 7.80 ppm and 7.73 ppm, confirming the conjugation of octanoyl and lauroyl chloride to 5-fluorocutosine, respectively. The purity of both analogs was 99.6%. We found that the XYZ-I-73 (IC50 3.6 ± 0.4μM) analog was most effective against MiaPaCa-2 cells compared to XYZ-I-71(IC50 12.3±1.7μM), GemHCl (IC50 24.2 ± 1.3 μM), Irinotecan (IC50 10.1 ± 1.5 μM) and 5-FU (IC50 13.2 ± 1.1 μM). For PANC-1 cell growth inhibition, XYZ-I-73 (IC50 3.9 ± 0.5) was again observed as the most effective agent compared to XYZ-I-71(IC50 8.7±0.9 μM), GemHCl (IC50 10.07±0.9), 5-FU (IC50 20.43±1.2) and Irinotecan (IC50 11.6 ±1.1). A similar pattern of XYZ-I-73 (IC50 5.9±0.7) anticancer activity against BxPC-3 cells was found to be higher than XYZ-I-71(IC50 7.7 ± 0.8), GemHCl (IC50 10.95±0.9), 5-FU (IC50 14±1.1) and Irinotecan (IC50 9.5±1.0). For 24-hour MiaPaCa-2 cell migration studies, XYZ-I-73 (5µM) analog significantly reduced migration (# of migrated cells, 168±2.9) followed by XYZ-I-71(315±2.1), Gem-HCl (762±3.1) and 5-FU (710±3.2). PARP studies demonstrated significant inhibition of PARP expression of XYZ-I-73 treated cells compared to 5-FU and XYZ-I-71. Further, BAX and p53 expressions were significantly increased in cells treated with XYZ-I-73 compared to 5-FU and XYZ-I-71. Metabolic stability studies showed that 80 ± 5.9 % of XYZ-I-71 and XYZ-I-73 remained intact after 2-hour exposure in liver microsomal solution compared to 5-FU. Conclusion: XYZ-I-73 demonstrated a remarkable cytotoxic effect and improved in vitro metabolic stability over the selected standard drugs and may have potential anticancer activity against pancreatic cancer. Citation Format: Esther Frimpong, Raviteja Bulusu, Joy Okoro, Andriana Inkoom, Nkafu Ndemazie, Sherise Rogers, Xue Zhu, Bo Han, Edward Agyare. Synthesis and biological evaluation of novel 5-FU analogs against pancreatic cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 1825.

SURFACE FUNCTIONALIZATION OF KENAF FIBERS WITH LAUROYL CHLORIDE: EFFECTS OF ALKALINE PRETREATMENT METHOD

Surface functionalization of cellulose fibers is the current focus of research seeking to develop composite materials for various applications. One reason is the low compatibility of natural cellulose-based fibers with thermoplastic matrices for the production of wood-plastic composites. In this research, kenaf fibers (KF) were esterified with lauroyl chloride. Before the esterification reaction, two alkaline pretreatment methods were used: Bain-Marie at low temperature, and at high temperature and pressure in the digester. SEM results showed a smoother surface morphology after esterification. ATR-FTIR results confirmed the substitution of hydroxyl groups of cellulose with lauroylate functional groups. Increasing the carbon content in EDX spectroscopy further supported the successful esterification of kenaf fibers, which is in accordance with ATR-FTIR findings. Based on ATR-FTIR and EDX results, the Bain-Marie pretreatment method was more effective for the esterification reaction. According to the XRD results, the crystallinity index of the fibers slightly increased after esterification reaction. However, the fibers pretreated in the digester had a higher crystallinity index, which was related to efficient removal of amorphous regions due to higher temperature and pressure used in the digester process. This research showed that alkaline pretreatment in Bain-Marie was more effective for the surface functionalization of cellulose fibers than the digester process. These results can be applied in future research works for esterification of cellulose fibers.

Novel Furfural-Derived Polyaldimines as Latent Hardeners for Polyurethane Adhesives.

Moisture-curing one-component polyurethane systems in adhesive, sealant, and coating applications may show blister formation upon cure. Blisters can be formed when carbon dioxide, generated in the reaction with isocyanate and water, is trapped in the film. This problem can be mitigated by employing latent hardeners such as blocked polyamines, which are activated upon moisture exposure. The hydrolysis of the latent hardener yields the polyamine that quickly reacts with the isocyanate, forming urea linkages, and then chain extends the polymer. The hydrolysis also releases the blocking agent, which can potentially create an unpleasant odor. In this work, a series of di- and trifunctional aldimines were synthesized from commercially available polyamines, biobased hydroxymethyl furfural, and lauroyl chloride. Hydroxymethyl furfural was first esterified with lauroyl chloride and subsequently condensed with the polyamines to form the aldimines. The application of these novel aldimines in a model moisture-curing system allowed the preparation of blister- and odor-free castings. Based on our results, the mechanical performance of the different aldimines in casting and adhesive applications could be related to the polymer network density. This was dependent on the rate of the aldimine hydrolysis reaction to produce the polyamine. In particular, the use of aldimines prepared from polyether amines and 1,5-diamino-2-methylpentane showed excellent adhesive properties.

Sandwich hydrogel to realize cartilage-mimetic structures and performances from polyvinyl alcohol, chitosan and sodium hyaluronate

Developing artificial substitutes that mimic the structures and performances of natural cartilage is of great importance. However, it is challenging to integrate the high strength, excellent biocompatibility, low coefficient of friction, long-term wear resistance, outstanding swelling resistance, and osseointegration potential into one material. Herein, a sandwich hydrogel with cartilage-mimetic structures and performances was prepared to achieve this goal. The precursor hydrogel was obtained by freezing-thawing the mixture of poly vinyl alcohol, chitosan and deionized water three cycles, accompanied by soaking in sodium hyaluronate solution. The top of the precursor hydrogel was hydrophobically modified with lauroyl chloride and then loaded with lecithin, while the bottom was mineralized with hydroxyapatite. Due to the multiple linkages (crystalline domains, hydrogen bonds, and ionic interactions), the compressive stress was 71 MPa. Owing to the synergy of the hydrophobic modification and lecithin, the coefficient of friction was 0.01. Additionally, no wear trace was observed after 50,000 wear cycles. Remarkably, hydroxyapatite enabled the hydrogel osseointegration potential. The swelling ratio of the hydrogel was 0.06 g/g after soaking in simulated synovial fluid for 7 days. Since raw materials were non-toxic, the cell viability was 100 %. All of the above merits make it an ideal material for cartilage replacement.

Transforming water-soluble carbon dots with high particle size regularity as the high-performance oil-based lubricant additives by one-step surface modification

Developing high-performance carbon dot (CD)-based lubricant additives towards non-polar base oils is always challenging because it is an arduous task to gain hydrophobic CDs with high quality. In this work, with the aid of the chemical reaction between hydroxyl groups and lauroyl chloride molecules, the water-soluble CDs-OH derived from the solvothermal method with particularly high particle size regularity were transformed as the oil-soluble CDs-LA by the one-step surface modification process. As expected, the CDs-LA capped by abundant long alkyl chain groups exhibited excellent long-term dispersion stability in non-polar base oil of polyalphaolefin (PAO4) and hence could be served as the additives of PAO4 directly. Under the same test conditions, the tribological performance of CDs-LA was obviously superior to the hydrophobic CDs obtained by the pyrolysis method, implying that the high particle size regularity was beneficial for making full use of the lubrication functions of CDs. Loading 1.7 wt% of CDs-LA made the friction and wear of PAO4 reduced by 32.2 % and 76.4 %, respectively. When the duration prolonged from 20 min to 200 min, the friction reduction of base oil triggered by CDs-LA further enlarged to 46.9 %. The friction-reducing and anti-wear performance of CDs-LA under high loads was also satisfactory. The worn surface analysis results demonstrated that the robust and homogenous boundary lubrication films composed of FexOy and CDs have generated on the rubbing surfaces lubricated by CDs-LA/PAO4 dispersion, well accounting for the outstanding friction reduction and wear resistance functions of CDs-LA.

Esterification of nanofibrillated cellulose using lauroyl chloride and its composite films with polybutylene succinate

Esterified nanofibrillated cellulose (eNFC) with varying degrees of substitution was prepared using fatty acid chloride. Furthermore, the effect of esterification on properties of pure NFC and its composites with polybutylene succinate (PBS) was investigated. Lauroyl chloride (LC) with 12 carbon atoms was used for esterification. An increase in the amount of LC increased the degree of substitution (DS), which significantly decreased the water contact angle and improved the hydrophobicity of NFC. The addition of fatty acid to NFCs lowered their crystallinity. However, the fatty acid increased the hydrophobicity of NFCs, thereby improving their dispersibility in nonpolar solvents. Compared with pure NFCs, eNFC exhibited enhanced compatibility with PBS, and the addition of eNFC with an appropriate DS increased the tensile strength and elastic modulus of PBS. These findings suggest the potential of NFC esterification for improving the performance of NFC-based composite materials.

Synthesis and characterization of sago starch nanocrystal laurate as a food grade particle emulsifier

Starch nanocrystals (SNCs) are tiny particles that possess unique qualities due to their small size, such as increased crystallinity, thin sheet structure, low permeability, and strong resistance to digestion. Although sago starch nanocrystals (SNCs) are naturally hydrophilic, their properties can be modified through chemical modifications to make them more versatile for various applications. In this study, the esterification process was used to modify SNCs using lauroyl chloride (LC) to enhance their surface properties. Three different ratios of LC to SNC were tested to determine the impact on the modified SNC (mSNC). The chemical changes in the mSNC were analyzed using FTIR and 1H NMR spectroscopy. ##The results showed that as the amount of LC increased, the degree of substitution (DS) also increased, which reduced the crystallinity of the mSNC and its thermal stability. However, the esterification process also improved the hydrophobicity of the SNC, making it more amphiphilic. The emulsification capabilities of the mSNC were investigated using a Pickering emulsion, and the results showed that the emulsion made from mSNC-1.0 had better stability than the one made from pristine SNC. This study highlights the potential of SNC as a particle emulsifier and demonstrates how esterification can improve its emulsification capabilities.

Preparation, Structure, and Photophysical Behavior of Europium (III) Complexes of Decyl Alanine and Lauryl Alanine

Two Ligands (H (dec-ala) and H (dod-ala)) prepared from decyl chloride, lauroyl chloride, and amino acids (DL-alanine), reacted with Europium chloride in methanol solution, leading to two Europium (III) complexes of Eu (dec-ala)3 and Eu (dod-ala)3.Elemental analysis, NMR, and FT-IR spectra proved the elemental content, structural information of the synthesized Europium (III) complexes. The light absorption and luminescence properties were characterized by UV-vis and PL spectra analysis. Both complexes have excellent absorption capacity in the range of 200 nm-300 nm. The ideal excitation wavelengths of these complexes are at 394 nm, and the principal emission peaks are at 590 nm, 610 nm, 650 nm, and 698 nm, which correspond to 5D0 → 7F1, 5D0 →7F2, 5D0→7F3, 5D0→7F4, respectively.

Green composites made of polyhydroxybutyrate and long-chain fatty acid esterified microcrystalline cellulose from pineapple leaf.

Pineapple leaf fibres are an abundant agricultural waste product that contains 26.9% cellulose. The objective of this study was to prepare fully degradable green biocomposites made of polyhydroxybutyrate (PHB) and microcrystalline cellulose from pineapple leaf fibres (PALF-MCC). To improve compatibility with PHB, the PALF-MCC was surface modified using lauroyl chloride as an esterifying agent. The influence of the esterified PALF-MCC laurate content and changes in the film surface morphology on biocomposite properties was studied. The thermal properties obtained by differential scanning calorimetry revealed a decrease in crystallinity for all biocomposites, with 100 wt% PHB displaying the highest values, whereas 100 wt% esterified PALF-MCC laurate showed no crystallinity. The addition of esterified PALF-MCC laurate increased the degradation temperature. The maximum tensile strength and elongation at break were exhibited when adding 5% of PALF-MCC. The results demonstrated that adding esterified PALF-MCC laurate as a filler in the biocomposite film could retain a pleasant value of tensile strength and elastic modulus whereas a slight increase in elongation can help to enhance flexibility. For soil burial testing, PHB/ esterified PALF-MCC laurate films with 5-20% (w/w) PALF-MCC laurate ester had higher degradation than films consisting of 100% PHB or 100% esterified PALF-MCC laurate. PHB and esterified PALF-MCC laurate derived from pineapple agricultural wastes are particularly suitable for the production of relatively low-cost biocomposite films that are 100% compostable in soil.

Ionic liquid-assisted isolation of lignin from lignocellulose and its esterification with fatty acids

Ionic liquids (ILs) have been widely used for lignocellulose fractionation and lignin isolation. However, the effect of IL treatment on lignin structure has been less explored. This study aimed to explore the chemical structure of lignin isolated by widely used imidazolium based ILs and compare it with the well-known milled wood lignin structure (MWL). Four types of ILs were used, and the effects of the treatment conditions on the isolated lignin (ILL) characteristics were evaluated. As the treatment temperature was increased from 60 to 140 °C, the ILL yield increased, whereas the molecular weight and hydroxyl group content decreased. Among the ILs, [EMIM]Ac produced the highest lignin yield (5.28%), and the ILL obtained had the lowest hydroxyl content (1.27 mM/g) and a molecular weight (Mw) of 29,500 g/mol. Esterification of the ILL isolated with [EMIM]Ac was performed using three fatty acid chlorides, octanoyl chloride (C8), lauroyl chloride (C12), and palmitoyl chloride (C16), to extend its applicability. The effects of esterification on the characteristics of ILL were evaluated, and successful esterification was confirmed using Fourier transform infrared and nuclear magnetic resonance spectroscopies.

Highly ordered asymmetric cellulose-based honeycomb membrane for moisture-electricity generation and humidity sensing

Moisture-trigged electricity generator (MEG) that can convert ubiquitous moisture into electricity are highly desirable for developing renewable energy supply and ameliorating the crisis in energy. Constructing an asymmetric ordered, namely gradient ordered porous membrane has great potential in MEG. Herein, a series of cellulose acetate (CA)-based membranes with ordered asymmetric honeycomb membranes were fabricated by Breath Figure method, along with silver nanowires (AgNWs) coating. The asymmetric gradient honeycomb pores were achieved by graft modification of lauroyl chloride and adjustment of relative humidity, which not only endowed the MEG with sensitive sensing signals transport under tension and humidity fluctuations but also enhanced voltages generation speed under flowing moisture. The current study provides a facile and scalable strategy for constructing asymmetric gradient ordered porous materials and creates more possibilities for MEG self-powered flexible wearable electronic devices.

Study on the synthesis and performance of sodium 2-laurylamido isobutyrate

Abstract In the present work, sodium 2-laurylamido isobutyrate was synthesized from 2-aminoisobutyric acid, NaOH and lauroyl chloride by the Schotten-Baumann condensation. Fourier transform infrared spectroscopy, mass spectroscopy and nuclear magnetic resonance spectroscopy were used to characterize the products, and confirming the successful synthesis of sodium 2-laurylamido isobutyrate. The influence of temperature on the surface tension of sodium 2-laurylamido isobutyrate was studied, comparing the chemical properties of the surface with those of sodium N-lauroyl sarcosinate. The results indicate that both surfactants have a similar pC 20, while the critical micelle concentration (CMC) and the surface tension at the critical micelle concentration (γ CMC) of sodium 2-laurylamido isobutyrate are higher than those of sodium N-lauroyl sarcosinate. Further studies on the thermodynamic parameters of sodium 2-laurylamido isobutyrate and sodium N-lauroyl sarcosinate indicate that the formation of micelles is a spontaneous exothermic process mainly driven by entropy. According to the dynamic surface tension of sodium 2-laurylamido isobutyrate and sodium N-lauroyl sarcosinate, the molecular adsorption of the two components mixture change from the initial diffusion controlled adsorption to the later mixed dynamic controlled adsorption.

Chemical characterization of black poplar (Populus nigra L.) sawdust hemicelluloses esterified with acyl chlorides

In the present study, hemicelluloses were isolated from black poplar (Populus nigra L.) sawdust, which is generated by the wood industry in large quantities as lignocellulosic waste. The monosaccharide composition of hemicelluloses was determined by gas chromatography. Xylose was the predominant monosaccharide unit, at 81.13%. Isolated hemicelluloses were then esterified with octanoyl, decanoyl, and lauroyl chloride, and the produced derivatives were characterized in terms of percent yield, degree of substitution (DS), solubility, Fourier-transform infrared spectroscopy (FTIR), and thermogravimetric analysis (TGA). Hemicellulose derivatives had DS values ranging from 0.83 to 0.97, and percent yields ranging from 61.54% to 62.31%. FTIR analysis confirmed esterification. TGA indicated that the hemicellulose derivatives offered lower thermal stabilities than native hemicelluloses. Solubility analysis indicated that esterification increased the hydrophobic capacity of hemicelluloses. Generally, the hemicellulose derivatives obtained could be used to make biodegradable and environmentally friendly plastics, resins, films, and coatings for industrial utilization.

Starch Formates: Synthesis and Modification.

Starch can be efficiently converted into the corresponding formates homogeneously using N-formyl imidazole obtained by the reaction of 1,1′-carbonyldiimidazole and formic acid in dimethyl sulfoxide as a solvent. Starch formates are soluble in polar aprotic solvents, not susceptible against hydrolysis, and not meltable. Thermoplastics could be generated by conversion of starch formates with long-chain fatty acids exemplified by the conversion with lauroyl chloride in N,N-dimethylacetamide, leading to mixed starch laurate formates. The mixed esters show melting temperatures mainly dependent on the amount of laurate ester moieties.

Development of a micro/nano composite super-hydrophobic silicon surface with nail-shaped texture/dual self-assembly monolayers and its wetting behavior

Micro-electromechanical systems often fail due to adhesion or wear, and preparing a stable super-hydrophobic surface is an effective approach to solve this problem. In this paper, the microscale square texture and nail-shaped texture were designed and fabricated, and the nanoscale N-[3-(Trimethoxysilyl) propyl] ethylenediamine- Lauroyl chloride (DA-LA) dual self-assembly monolayers (SAMs) was developed to form a micro/nano composite structure. Meanwhile, micro/nanoscale surface morphology, chemical composition and surface free energy were characterized or calculated. Further, wettability and stability experiments were carried out. The results showed that the micro/nano composite structure achieves super-hydrophobicity and enhanced stability, and the maximum contact angle reaches 170.35°. The nail-DA-LA surface with a 54.7°overhang angle and rough sidewalls exhibited prominent super-hydrophobic stability, and the tribological experiments showed that the adhesion/friction reduced by 46.71% and 52.26%.

SYNTHESIS OF N-LAUROYL SERINAMIDE THROUGH AMIDATION REACTION OF SERINE WITH METHYL LAURATE AND AMIDATION REACTION OF SERINE WITH LAUROYL CHLORIDE

Research on synthesis N-lauroyl serinamide through serine reaction with methyl laurate and lauroyl chloride has been carried out. Synthesis N-lauroyl serinamide by two reaction methods, the first method was through the esterification reaction of lauric acid to produce methyl laurate and then an amidation reaction was carried out by serine to produce N-lauroyl serinamide with percent yield of 73.86% and HLB value of 6.54. Through the FTIR test showed vibration absorption of the carbonyl amide group at wave number 1624.96 cm-1. The second method is through the chlorination reaction where lauric acid is converted to lauroyl chloride and then an amidation reaction is carried out by serine to produce N-lauroyl serinamide with percent yield of 93.75% and HLB value of 7.27. Through the FTIR test showed vibration absorption of the amide carbonyl group at wave number 1631.78 cm-1. The result shows that N-lauroyl serinamide can be synthesized through serine reaction with methyl laurate and lauroyl chloride which can be used as an emulsifier o/w (oil in water).

Effect of the Degree of Substitution on the Hydrophobicity, Crystallinity, and Thermal Properties of Lauroylated Amaranth Starch.

In this paper, we consider amaranth starch extracted from the seeds of Amaranthus hypochondriacus L. An amphiphilic character is conferred to the starch by a chemical modification, which involves an esterification by lauroyl chloride at three modification levels. The degree of substitution (DS) after the modification ranged from 0.06 to 1.16. X-ray photoelectron spectroscopy analysis confirmed the presence of fatty acyl chains on the surface of the esterified starches. The hydrophobicity of starches was confirmed by their adsorption isotherms, which showed a decrease in the moisture adsorption of lauroylated as DS increased. X-ray diffraction analysis revealed a higher crystallinity, which was observed in the two samples subjected to the highest levels of modification. A higher crystallinity is related to a higher gelatinization enthalpy. These results are in agreement with the thermal characterization obtained by differential scanning calorimetry (DSC). An inhibition of the retrogradation properties of lauroylated amaranth starches was also observed.