Types Of Silane Coupling Agents Research Articles

Exploration of surface treatment and liquid additive processing for enhanced multilayer ceramic capacitors performance

This study proposes the development of an optimum multilayer ceramic capacitor (MLCC) that exhibits outstanding performance. Novel research on the improvement of the dispersibility of the dielectric slurry using BaTiO3 is carried out and the results are analyzed and assessed. To improve the dispersibility of the fine powder, various types of silane coupling agents are used to comparatively analyze properties of the dielectric sheet and the MLCC sample chip. In addition, a powder form Dy is generally used to improve the reliability of MLCC dielectric properties; nonetheless, outstanding properties are achieved by applying a liquid form Dy. Therefore, this research combines the optimal surface treatment method of the ferroelectric powder for the manufacture of outstanding MLCCs and the method of treating liquid form additive to achieve innovative research results to obtain MLCCs with outstanding performance.

Improving performance of natural rubber composites by the application of functional biofiller: horsetail modified with silane coupling agents

The growing ecological awareness of society and increasingly stringent legal requirements regarding environmental protection and the strategy of implementing the principles of sustainable development force the search for and continuous development of environmentally friendly solutions in the field of polymer materials technology. One of the directions is the use of raw materials from renewable sources. For this reason, the research object of the presented work was natural rubber composites containing a filler of plant origin in the form of ground horsetail (HT) biomass. Despite its health-promoting properties, it is commonly considered a weed. What’s more, the ubiquitous occurrence and surplus make it a valuable source of waste biomass for management. Taking into account the limitations resulting from the hydrophilic nature of the lignocellulosic filler, and the related poor adhesion to the non-polar elastomer matrix, the horsetail filler was modified with organoalkoxysilanes. The study used silane compounds containing groups that can affect the properties of vulcanizates in various ways, such as vinyltriethoxysilane (VTES), 3,3′-Tetrathiobis(propyl-triethoxysilane) (TESPTS), 3-(aminopropyl)triethoxysilane (APTES), 3-(chloropropyl)triethoxysilane (CPTES) and octyltriethoxysilane (OTES). The biomass in the form of field horsetail was previously modified with selected silanes. Then, the bioadditive prepared in this way was applied to rubber mixtures. The process of modifying the natural filler contributed to structural changes in the lignocellulosic material, which may indicate the effective attachment of silane compounds to the horsetail surface. The results of the contact angle analysis show that the treatment strongly influenced the surface characteristics of the fillers, making them more hydrophobic. The results show that the type of silane coupling agent affects not only the processing associated with the vulcanization process but also the mechanical properties of the NR vulcanizates. This phenomenon is probably the result of increased rubber-bioadditive interaction and improved filler dispersion. Moreover, all composites with modified HT, show a greater flame permanence time than the one using unmodified filler.Graphical abstract

Effect of Different Silane Coupling Agents on Properties of Waste Corrugated Paper Fiber/Polylactic Acid Composites.

The surface of plant fibers was modified by silane coupling agents to prepare plant fiber/polylactic acid (PLA) composites, which can improve the dispersion, adhesion, and compatibility between the plant fibers and the PLA matrix. In this work, three silane coupling agents (KH550, KH560, and KH570) with different molecular structures were used to modify the surface of waste corrugated paper fibers (WFs), and dichloromethane was used as the solvent to prepare the WF/PLA composites. The effects of different silane coupling agents on the microstructure, mechanical properties, thermal decomposition, and crystallization properties of the composites were studied. The mechanical properties of the composites treated with 4 wt% KH560 were the best. Silane coupling agents can slightly improve the melting temperature of the composites, and WFs can promote the crystallization of PLA. The modification of WFs by silane coupling agents can increase the decomposition temperature of the WF/PLA composites. The content and type of silane coupling agent directly affected the mechanical properties of the WF/PLA composites. The interfacial compatibility between the WFs and PLA can be improved by using a silane coupling agent, which can further enhance the mechanical properties of WF/PLA composites. This provides a research basis for the further improvement of the performance of plant fiber/PLA composites.

Silane modification of nanofibrillated cellulose and its effect on the properties of waterborne acrylic resin

AbstractNanofibrillated celluloses (NFC) have attracted tremendous attention as nanofillers to improve the mechanical properties of waterborne resin. In this study, NFC was prepared by mechanical fibrillation, and then modified respectively with three different types of silane coupling agents: γ‐aminopropyltriethoxysilane (KH550), γ‐(2, 3‐epoxypropoxy) propyl trimethoxysilane (KH560), and γ‐(methacryloyloxy) propyl trimethoxysilane (KH570). The obtained NFC and modified NFCs were physically mixed with water‐based acrylic resin (WAR) to prepare films by casting method. The NFC, silanized NFC, and films were analyzed by Malvern laser particle sizer, scanning electron microscopy (SEM), Fourier transform infrared (FTIR), thermogravimetric analyzer (TGA), water contact angle (WCA), rotational rheometer, and power stretchers, respectively. Results showed that NFCs were successfully prepared and modified. The KH570 modified NFC had a slightly smaller particle size, higher absolute Zeta potential and yield stress values, good thermal stability, and exhibited better dispersion and suspension stability in solution. However, the NFC modified by KH560 had the best improvement effect on the mechanical properties and hydrophobicity of WAR membranes. Adding only 0.3 wt% KH560 modified NFC could increase the tensile strength of WAR film by 131.9%, and the WCA of the film could be increased from 85.2° to 101.6°, which makes this study beneficial for promoting the application of nanofibrillated cellulose in WAR.

High thermal conductivity insulating AlN/poly(m-phenylenedicarbonyl-m-phenylenediamine) paper realized by enhanced compatibility: a selection of appropriate coupling agent

Encouraged by the goal of achieving net-zero carbon emission by 2050, the exploration of insulating material becomes one of the core projects to the electrical equipment innovations. The rise of composites enables the insulating material to be endowed with more functions. By this concern, adopting the coupling agents is one of the effective methods to improve the compatibility of composites, which highly strengthens the desired properties. The functional groups of coupling agents, nevertheless, could not always show a positive impact to access enhanced properties. In this work, four types of silane coupling agents including amino-propyl, glycidyletheroxy-propyl (GP), vinyl, and methacryloxy-propyl functional groups are employed to modify the aluminum nitride (AlN) fillers, and the modification effects on the insulating and thermal conductivity of the AlN/poly(m-phenylenedicarbonyl-m-phenylenediamine) (PMIA) composite paper are systematically investigated and compared. The results show that a proper coupling agent is beneficial to the uniform dispersion of the inorganic filler in the organic matrix and highly contributes to their interface quality, where the heat transfer path is established that boosts the heat dissipation. By tailoring the trap depth and density toward deeper and higher, the carrier transport is highly confined which enhances the breakdown strength to a large extent. Therefore, high breakdown strength and thermal conductivity of 182.9 kV mm−1 and 0.302 W (m·K)−1, respectively, are achieved in the GP modified AlN/PMIA paper, which are 16.7% and 167.4% higher than that of pure PMIA paper.

The improvement in properties of polyester resin-based composites using a new type of silane coupling agent

Adhesion between the polymer matrix and fillers is an important factor influencing the properties of the obtained composites. One way to improve interactions at the interface is to modify the filler with coupling agents, e.g., silanes. The article presents the effect of modifying the surface of the mineral filler with a new type of silane [triethoxy(ketoimino)silane] on the mechanical properties of polyester resin based composites. Composites with triethoxy(ketoimino)silane-modified filler had similar mechanical properties to composites obtained with commercial silanes, with slightly lower water absorption.

Effect of silane coupling agent and concentration on fracture toughness and water sorption behaviour of fibre-reinforced dental composites.

This paper presents the effect of silane treatment of S-2 Glass fibres on the fracture toughness and water sorption/solubility behaviour of fibre-reinforced flowable dental composites. The effect of epoxy- and methacrylate-based silane coupling agents (SCAs) on the mechanical strength and hydrolytic properties were investigated. The concentration of the selected SCAs on the mechanical and physical properties were investigated. The influence of molecular structure and concentration in the interfacial adhesion at the fibre-matrix interfaces was also studied. Short S-2 Glass fibres of 250µm in length and 5µm in diameter were etched with acid to remove any impurities and roughen the surface. The acid-etched fibres were silane treated with 3MPS, 3GPS, and 8MOTS at different concentrations by weight (%). The silane-treated fibres were incorporated at 5 % into the dental resin mixture. Untreated fibres were added at 5 % to the dental resin mixture and served as the control group. The physical properties such as water sorption, solubility, and desorption along with mechanical properties such as fracture toughness and total fracture work of the fibre-reinforced dental composites grafted with the above-mentioned SCAs were evaluated. The surface morphology of the fractured surface was studied and analysed. The fracture toughness tests showed that the dental composites grafted with optimum weight per cent (wt. %) concentration of the SCA had a better stress intensity factor (KIC) when compared to the 2.0wt. % and 3.0wt. % concentration. The KIC value of dental composites grafted with untreated surface etched glass fibres was less than the KIC values of dental composites grafted with optimum concentrations of 3MPS, 3GPS, and 8MOTS by 81.6 %, 38.6 %, and 110.5 %, respectively. A similar trend was found while investigating the total work of fracture of the dental composites, between optimum concentration, 2.0wt. % and 3.0wt. % concentration of respective SCA. The increase in silane concentration also led to an increase in the water sorption/solubility characteristics. The absorption of water was most severe in the fibre-reinforced dental composites without silane treatment (32.9µg/mm3). The ANOVA results showed that the fibre-reinforced dental composites grafted with 8MOTS at optimum concentration showed an increase in fracture toughness when compared to optimum concentrations of 3GPS and 3MPS by 51.9 % and 15.9 %, respectively. The enhanced mechanical and physical characteristics are due to the increased adhesion between the fibre and silane achieved from the optimum wt. % concentration of 8MOTS. Similarly, dental composites grafted with 8MOTS at optimum concentration showed a decrease in water sorption characteristics when compared to optimum concentrations of 3GPS and 3MPS by 18.2 % and 0.6 %, respectively. The decreased water sorption characteristics at the optimum concentration of 8MOTS could be due to the reduced availability of reactive hydroxyl groups and the hydrophobic characteristics of 8MOTS. Silane coupling agents (SCAs) are important components of dental composites. The type and concentration of SCA have a significant effect on material properties. The current study focuses on understanding the effects of different SCAs and wt. % concentrations on the interfacial fracture behaviour and the influence of different SCAs on the water sorption and solubility behaviour of S-2 Glass fibre-reinforced flowable dental composites.

Effect of Corrosive Aging Environments on the Flexural Properties of Silane-Coupling-Agent-Modified Basalt-Fiber-Reinforced Composites.

In recent years, basalt-fiber-reinforced polymers (BFRPs) have been widely used in the field of corrosive aging resistance. In this paper, BFRPs are made into composite laminates, and the flexural properties of BFRPs modified with different types of silane coupling agents, KH550 (aminopropyl-triethoxysilane), KH560 (glycidyletheroxypropyl-trimethoxysilane), and A171 (vinyl-trimethoxysilane), immersed at 20 °C, 40 °C, and 60 °C in a 3.5% NaCl concentration artificial seawater, a 10% NaCl high-concentration artificial seawater, 10% H2SO4, or 10% NaOH are investigated. The results show that the flexural strength decreased with increasing exposure time in corrosive aging environments at different temperatures. The temperature greatly influences flexural strength, and the flexural strength decreases rapidly in high-temperature acidic and alkaline environments. In addition, we found that the flexural retention in the seawater environment did not change much compared to that in the water environment, indicating that BFRPs have relatively good resistance to seawater corrosion. The silane coupling agent modification enhances flexural strength and flexural strength retention by enhancing the interfacial bonding property of the BFRPs. Considering the experimental results, the three silane coupling agents modified the corrosive aging performance of the composites in the order of KH550 > KH560 > A171. This will provide theoretical support for the application of silane-coupling-agent-modified BFRPs in corrosive aging environments.

Developing Crumbed Rubber Tires / Epoxy Composite, by Surface Treatment with Different Silane Coupling Agents

Converting used tries to useful materials and avoiding harmful effects of accumulation used tires, is a great economic and environmental issue. Using of crumbing rubber of used tires CRT as filler materials shows declining in mechanical properties of CRT/polymer composites as weak bonding between CRT and polymeric matrices. This work include, CRT surface treating by three kinds of silane coupling agent, Trimethoxysilyl propyl methacrylate, 3-chloropropyl triethoxy silane and Silicic acid, before using as filler materials in epoxy matrix. 10 wt. % of non-treated and treated CRT/epoxy composite specimens have been prepared and tested to evaluate effect of CRT surface treatment into composite mechanical properties. The results show that modulus of elasticity, tensile strength, and fracture toughness of treated CRT/epoxy composite could improve by 56%, 30%, 36% respectively comparing with that of non-treated CRT/epoxy, after treating by 3-chloropropyl triethoxy silane coupling agent, whereas surface treating by other types of silane coupling agents could produce less mechnical improvement but still better that of non-treated.

Coating performance, durability and anti-corrosion mechanism of organic modified geopolymer composite for marine concrete protection

Geopolymer has excellent chemical resistance, while the high shrinkage prohibited its application in marine concrete coating. To solve this problem, organic modified metakaolin based geopolymer (MG) composites were synthesized with waterborne epoxy resin (WR) at 10%, 20% and 30%, and three types of silane coupling agents (SCA) at 1%, respectively. Multiple coating performance related properties were assessed, with the organic-inorganic interaction explored using SEM-EDS, XRD, FTIR and MIP. The organic-MG composites presented apparent enhancement in coating performance, with 30% WR- and 1% S823- modified MG having the most promising properties. Particularly, MG-WR performed better in shrinkage reduction, adhesion, anti-abrasion and Cl− corrosion resistance; while MG-SCA had better durability in seawater and carbonation conditioning. These were attributed to the more compact microstructure configurated through (i) pore filling of WR in geopolymer matrix; (ii) hydrogen bonds formed between waterborne hardener, epoxy resin, geopolymer and water; and (iii) SCA-geopolymer crosslinked networks formed via silanol-aluminosilicate condensation, respectively.

Additive manufacturing of complex-shaped and high-performance aluminum nitride-based components for thermal management

Improved heat dissipation performance, by way of thermal management, is critical in many engineering applications. In this study, three types of silane coupling agents were used to modify aluminum nitride (AlN) powder for vat photopolymerization. The effect of silane coupling agents on the rheology, stability, and curing behavior were systematically studied. The results showed that, compared with two other types of silane coupling agents, one silane agent (KH570) had a larger positive effect on the rheology and stability of the AlN suspension, and the absorbance of the AlN powder increased after surface modification. In addition, the effects of different solid loadings on the curing behavior and CC double-bond conversion rate were systematically investigated. It was found that a higher solid loading resulted in a lower curing depth, cure width, and CC double-bond conversion rate. For the sintered AlN components with increased solid loading, the shrinkage decreased while both the flexural strength and thermal conductivity increased. In addition, the shrinkage in the Z-direction was higher than that in the X- and Y-directions. Scanning electron microscopy analysis showed that the mean grain size decreased with increasing solid loading. Furthermore, a heat dissipation performance evaluation system was designed to illustrate the heat transmission capacity of AlN ceramics. Simulation and experimental results showed that AIN ceramic parts with complex shapes achieved better heat-dissipation performance than those with simple shapes.

Enhancing mechanical performance and wet‐skid resistance of emulsion styrene butadiene rubber/natural rubber latex composites via in‐situ hybridization of silanized graphene oxide and silica

AbstractThe wet skid resistance and thermal conductivity of “green tire” are the focus of research. In this work, through the use of different types of silane coupling agents, the surface of SiO2 and graphene oxide (GO) were grafted with amino and epoxy groups, respectively. The in‐situ generated SiO2 was grafted to the surface of GO by ring‐opening reaction of amino and epoxy groups. The emulsion styrene butadiene rubber/natural rubber latex (ESBR/NRL) composites were prepared by gas assisted spray flocculation process to improve the dispersion performance of hybrid filler. Because the surface of the hybrid filler contains amino and epoxy groups, it can be added as a reactive compatibilizer into the ESBR/NRL composites to improve the interface compatibility and synergistic reinforcement effect. Compared with the composites filled with SiO2, the composites filled with hybrid filler have excellent wet skid resistance and mechanical properties. When the mass ratio of GO to SiO2 is 3:10, the mechanical properties and wet skid resistance of rubber composites increase by 96.7% and 20.6%, respectively. Our preparation method of hybrid filler and flocculation process of rubber composites have broad application prospects in “green tire.”

Molecular interaction of Asphalt-Aggregate interface modified by silane coupling agents at dry and wet conditions

This study investigated interfacial behavior of asphalt-aggregate system modified by silane coupling agents (SCA). Molecular dynamics (MD) were used to simulate the interface between asphalt binder and silica grafted with three SCAs with different functional groups. At dry condition, the transition zone thickness and contact angle between asphalt binder and modified aggregate surfaces were compared. At wet condition, the effects of SCAs on interaction energy and hydrogen bond were analyzed. The simulated results are in good agreement with experimental measurements reported in the literature. It was found that the SCA modification could improve the adhesion between asphalt and aggregate at both dry and wet conditions. The thicker transition zone between asphalt and aggregate after SCA modification could enhance the compatibility and improve the force transfer between asphalt and aggregate. In addition, the wettability of asphalt binder on the SCA-modified aggregate surface was found better from the simulated contact angle. The grafted SCA on aggregate surface increased the resistance of asphalt-aggregate interface to moisture damage through increased interaction energy and less potential of hydrogen bonds. Although all three types of SCAs had positive benefits on interfacial bonding of asphalt-aggregate systems, the SLA with amino group showed superior performance.

A comparative study on dry‐sliding wear behavior of graphene oxide/epoxy nanocomposites functionalized by amino‐ and epoxy‐silane coupling agents

AbstractTo enhance the interfacial bonding between the graphene oxide nanoplatelets (GONs) and epoxy (EP) matrix, two different types of silane coupling agents (amino‐ and EP‐silane) were applied to the GONs‐EP nanocomposites. The effects of the silane compound type and silanized GON loading (0.1–0.5 wt% at an interval of 0.2) on the dry‐sliding wear response of GONs‐EP nanocomposites were then studied. The wear tests were conducted under 20 N load and 1000 m sliding distance. The results showed that the wear properties were remarkably improved by the incorporation of silanized GONs to the matrix, and the best wear behavior was obtained at 0.3 wt% silanized GONs. Most importantly, the amino‐silane coupling agent was shown to be more effective in enhancing the wear resistance of the GONs‐EP nanocomposites. After the wear tests, the composite surfaces were studied by scanning electron microscopy to find the predominant mechanisms.

Investigation of mechanical properties and dispersion in silica/Styrene Butadiene Rubber (SBR) nanocomposites: A ReaxFF molecular dynamics study

Various factors that affect nanoparticles’ (NP) strength and dispersion in silica-Styrene Butadiene Rubber (SBR) nanocomposites are determined using ReaxFF molecular dynamics simulations. Factors such as the size of silica NP, type of Silane Coupling Agent (SCA), surface occupancy of SCA at the silica surface and spatial distribution of sulphur cross-links at a molecular scale are considered. Various parameters like peak normal traction, strength modulus, interface energy, radius of gyration, and distance between NP of different systems were monitored to determine which factors significantly influence NP’s strength and dispersion. It was found that the strength increased with both the size and volume fraction of the NP. The size of the NP or the type of the SCA did not affect the dispersion at all. The dispersion of NP was found to depend on the surface occupancy of a given SCA significantly. Furthermore, it was observed that the introduction of sulphur cross-links farther from the NP increased the tensile strength of the nanocomposite than if they were closer to the NP. This result indicates that controlling the distribution of sulphur cross-links may significantly influence the strength of the nanocomposite.

Influence of silane type and application time on the bond strength to leucite reinforced ceramics

Introduction All-ceramic restorations currently dominate the market of indirect restorative materials due to their biocompatibility, longevity and superior aesthetics [1]. Silica-based ceramics, such as leucite, carry the advantage of being receptive to surface treatments, making them bondable to tooth substrates [2]. However, a standardised application protocol regarding silane coupling agents is lacking. Such step is critical to ensure durability of the restoration placed in situ. Post-etch cleaning and silane application have been proven to increase bond strength, however, this step varies for each material [3]. The aim of this research was to assess the influence of different types of silane coupling agents and respective application times on the bond strength of the ceramic-resin interface. Materials and methods Ten leucite reinforced glass ceramic blocks (IPS Empress CAD LT BL4/C 14) were divided into equal halves. Of the samples obtained, 6 were randomly divided into three groups according to the silane used: G1 BIS-Silane (Bisco, Schaumburg, IL, USA); G2 ESPE Sil Silane Coupling Agent (3 M ESPE AG, Seefeld, Germany); G3 Monobond Plus (Ivoclar-Vivadent, Schaan, Liechtenstein). Each was then divided into two subgroups, according to the surface conditioning time: T1 (1 min.) or T2 (5 min.). Each block was acid etched (HF 9.5% − 1 min), post-etching cleaned (OPA 37.5% − 1 min; ultrasonication − 2 min.) and silanized. Heat treatment was carried out at 100 °C (1 min.). Then a thin layer of Optibond FL (Kerr) adhesive was applied and each block was adhered to pre-heated resin at 55 °C. The samples were light cured for 40 s on each side (1200 mW/cm2). Samples were sectioned into microspecimens (1 ± 0.2 mm2) that were subjected to aging (10,000 thermocycles − 5 and 55 °C). The microspecimens were tested in tension at a crosshead speed of 0.5 mm/min, until they debonded. Data analysis was carried out by a two-way ANOVA, at a significance level of 5%. Results The group featuring BIS-Silane with longer application time (G1T2) presented a mean µTBS value (32.4 ± 19.6 MPa) significantly higher to all other groups (p < .001). Monobond Plus registered the lowest mean µTBS value (G3T1 − 18.5 ± 7.3 MPa) and (G3T2 − 17.3 ± 5.8 MPa). The type of silane coupling agent has shown to have a significant influence on the microtensile bond strength (p = .001; η 2=0.16). Discussion and conclusions Some authors have previously suggested that silanization could benefit from longer application times, but seldom research has been found featuring this variation protocol [3,4]. Silanes require a hydrolysation process in order to establish chemical bonds. Two-bottle systems show the highest bond strength results and may benefit from longer application times. The addition of 10-MDP seems to have no significant advantage over traditional silane coupling agents.

Sr2MgSi2O7:Eu2+, Dy3+ phosphor‐reinforced wood plastic composites with photoluminescence properties for 3D printing

AbstractCombining wood plastic composites with 3D printing technology can easily manufacture parts with complex shapes and wood colors, but the single function limits their applications. In this research, Sr2MgSi2O7:Eu2+, Dy3+ phosphors/particleboard wood flour/poly (lactic acid) (SMSED/PWF/PLA) photoluminescence composites for 3D printing were successfully manufactured by melt extrusion. The water resistance and chemical structure of SMSED phosphors modified with five different types of silane coupling agents were characterized by water‐resistance test, Fourier transform infrared spectroscopy, and X‐ray diffraction. It was found that 3‐aminopropyltriethoxysilane (KH550) had the best effect on the modification of SMSED phosphors, formed a dense protective film. Afterward, the effect of KH550‐modified SMSED (KH550‐SMSED) phosphors content on the thermo‐mechanical properties of wood plastic composites was studied. The experimental results indicated that the mechanical properties and thermal stability of wood plastic composites were significantly improved, with the incorporation of KH550‐SMSED phosphors. Finally, based on SMSED/PWF/PLA composites and 3D printing technology, a safety warning model that could emit blue light in the dark and a small dinosaur artwork that could swing flexibly were prepared.

Aminopropyltriethoxy silane in natural rubber/silica composites: Torque and vulcanization properties

The performance of rubbers composites in engineering application depend on the compatibility between reinforcing fillers and rubbers. It is a concern especially when forming rubbers composites with much contrasting of polarities between the rubbers matrix and the reinforcing fillers. However, correct compatibilizer will settle the poor interactions. This study; natural rubber (NR)/precipitated silica (PSi) composites were compounded together with aminopropyltriethoxy silane (AS) as a compatibilizer. The AS is one type of silane coupling agents and it was compounded into the composites of NR/PSi with varied doses i.e. one to seven phr. It was found that the AS significantly affected the torque and vulcanization properties of the NR/PSi composites. The AS decreased the viscosity/minimal torque but raised the maximal torque and torque differentiation. It was also found that the AS increased the rate of vulcanization. The increases in the torque and vulcanization properties were presumably attributed to the enhancement in rubber to filler interactions originating from coupling bonds formation in the presence of AS as a compatibilizer. Besides, the AS also role as a plasticizer which increased the degree of filler dispersion of PSi. Therefore, the addition of AS had a considerable potential to compatibilize the non-polar NR and PSi filler.

The Effect of Nano-Silica Modified With Silane Coupling Agents on the Diffusion Behavior of Water Molecules in Palm Oil Based on Molecular Simulation

To enhance the compatibility of nano-SiO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> and palm oil, four different types of silane coupling agent (KH550, KH560, KH570 and KH792) were adopted to modify the surface of silica. It turns out that when using the KH792 to modify the surface of nano-SiO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> , the interfacial bonding between silica and palm oil was maximum and their overlapping area was the largest, up to 12 Å. Thus, it can be concluded that the relatively optimal silane coupling agent is KH792. And when nano-SiO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> , whose surface was modified with KH792, was added to the palm oil, the interaction energy between palm oil and water molecules was enhanced and the diffusibility of water molecules in oil was decreased. In addition, the addition of nano-SiO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> to the oil reduced the diffusible space of water molecules provided by oil and further restricted the diffusion of water molecules in oil. Therefore, it can be seen that the addition of nano-SiO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> to palm oil may cause the restriction of the diffusion of water molecules in it.

Physical properties and morphology of siloxane–polyacrylate dispersion and coating films

The aim of this work was to study the morphology and physical properties of siloxane–polyacrylate (SPA) dispersion and coating films. The SPA dispersion was synthesized by seeded emulsion polymerization using two different types of silane coupling agents, i.e., vinyltriethoxysilane (VTES) and 3-(trimethoxysilyl) propyl methacrylate (MPTMS), at 1–9% by weight. The effect of the type and content of silane coupling agent used in the SPA dispersion synthesis on the resulting morphology and physical properties of the obtained SPA dispersion and coating films were studied. The results revealed that SPA dispersion synthesized using VTES exhibited a smaller particle size and a higher stability than those using MPTMS. Furthermore, the hydrophobic surfaces and water repellence of the coating films using VTES in the emulsion were higher than those using MPTMS, due to the smoother surface morphology.