3-methacryloxypropyl Trimethoxysilane Research Articles

Study on Effect of Surface Treating Method on Mechanical Behavior of Three Plant Fiber Reinforced Polypropylene Composites

The surface modification effects of triethoxysilane (KH-550), methacryloxy propyl tri-methoxy silane (KH-570), and maleic anhydride grafted polypropylene (MAPP) on sawdust (SD), wheat straw (WS) and cellulose (CE) were studied by a tensile test, as well as surface morphology observation on reinforced composites. The results revealed that MAPP was the most effective coupling agent, and SD composites performed better than WS and CE. The tensile test results indicated that the optimum conditions for coupling agents were 1 wt.% for silane coupling agents and 5 wt.% for MAPP. SEM studies confirmed the tensile test results, proving that adhesion was improved with the employment of MAPP. MAPP-treated composite samples presented a prevailed fiber broken pattern which resulted in strong fiber-matrix interface bonding, whereas silane treatments did not provide an obvious enhancement in adhesion between the fiber and the matrix.

Highly selective coextraction of rhodamine B and dibenzyl phthalate based on high-density dual-template imprinted shells on silica microparticles.

A simple one-pot approach based on molecularly imprinted polymer shells dispersed on the surface of silica for simultaneous determination of rhodamine B and dibenzyl phthalate (DBzP) has been developed. Highly dense molecularly imprinted polymer shells were formed in the mixture of acetonitrile and toluene by the copolymerization of methacrylic acid and ethylene glycol dimethacrylate, as well as two templates, rhodamine B and dibenzyl phthalate, directed by the vinyl end groups functional monolayer at surface silica microspheres after 3-methacryloxypropyl trimethoxysilane modification. The obtained imprinted polymer shells showed large average pore diameter (102.5 nm) and about 100 nm shell thickness. The imprinted particles also showed high imprinting factor (αRhB = 3.52 and αDBzP = 3.94), rapid binding kinetics, and excellent selective affinity capacity for rhodamine B and dibenzyl phthalate containing another three competitors in mixed solution. Moreover, the imprinted particles coupled with ultra high performance liquid chromatography was successfully applied to simultaneous analysis of rhodamine B and dibenzyl phthalate in two spiked beverage samples with average recoveries in the range of 88.0-93.0% for rhodamine B and 84.0-92.0% for dibenzyl phthalate with the relative standard deviation lower than 5.1%.

Structural, electrical and optical properties of silane-modified ZnO reinforced PMMA matrix and its catalytic activities

3-Methacryloxy propyl trimethoxy silane (KH-570) modified zinc oxide (mZnO) reinforced poly (methyl methacrylate) (PMMA) nanocomposite was synthesized via in-situ polymerization technique. The structural and optical properties of ZnO reinforced PMMA matrix were examined through X-ray diffraction (XRD) spectroscopy, Fourier transform infrared (FTIR) spectroscopy, field effect scanning electron microscopy (FESEM) and UV–vis spectroscopy. The energy storage capacity was estimated through dielectric permittivity and dielectric loss measurement using broadband dielectric spectroscopy. The electrochemical performance was examined through CV and SWV techniques. FESEM images revealed homogeneous dispersion of mZnO into PMMA matrix. The PMMA-mZnO nanocomposite showed maximum absorption in the UV-region (200nm–280nm). The incorporation of mZnO into the host polymeric PMMA matrix significantly improved the dielectric constant (ε′=81) as compared to unmodified ZnO (ε′=10). Further, it markedly contributed to the electrochemical response and improved their catalytic activities as well. These results lead to the understanding that the PMMA-mZnO nanocomposite is a successful candidate for the fabrication of energy storage devices.

Double cross-linking PVA-SiO2 hybrid membranes for alkali recovery

Abstract Non-charged PVA-SiO2 hybrid membranes are prepared through sol-gel process among polyvinyl alcohol (PVA) and double cross-linking agents, which are selected from four types of alkoxysilanes including tetraethoxysilane (TEOS), tetramethoxysilane (TMOS), γ-aminopropyl triethoxysilane (APTEOS) and methacryloxypropyl trimethoxy silane (MPS). The double cross-linking agent can combine their advantages including different hydrolysis rates of OC2H5 and OCH3 groups, high compatibility of NH2, and polymerizable C C bonds. The NH2 group from APTEOS can enhance membrane homogeneity, thermal stability and flexibility due to its compatibility with PVA–OH groups. The membranes have high selectivity (62–101) but low permeability in diffusion dialysis process for separating NaOH/Na2WO4 solution. Single type of Si(OCH3) groups produces large silica particles (1.5–5μm), which reduce membrane stability but enhance permeability. The membrane has low strength and flexibility, and high swelling degrees in 65 °C water (373–408%) and weight loss percentage in 65 °C NaOH solution (25.8–28.7%). The permeability can reach up to 0.0076–0.0092 m/h but the selectivity is only 23.7–25.0 at 20–40 °C. The combination of Si(OCH3) and Si(OC2H5) groups (TEOS and MPS) can obtain high strength and flexibility (20.3 MPa, 571%), acceptable swelling degrees (232–279%) and balanced permeability and selectivity (0.0043–0.0071 m/h, 45–110). Hence, double cross-linking agents can be combined to prepare optimized neutral membranes for diffusion dialysis.

Preparation of poly (octadecyl methacrylate)/silica-(3-methacryloxypropyl trimethoxysilane)/silica multi-layer core-shell nanocomposite with thermostable hydrophobicity and good viscosity break property

In this study, a multi-layer core-shell nanoparticle with multiple functions was prepared by a two-step process. First, the hydrolysis-condensation reaction of 3-methacryloxypropyl trimethoxysilane (MPS) and tetraethoxysilane (TEOS) was performed on the surface of the pre-synthesized SiO2 nanoparticles to form the MPS/SiO2 core-shell nanoparticles. Second, the copolymerization of octadecyl methacrylate (ODMA) monomers with CC bonds was carried out on the surface of MPS/SiO2 nanoparticles to form PODMA/MPS/SiO2 multi-layer nanocomposite. The hybrid nanocomposite could be used directly as the thermostable hydrophobic coatings. The prepared coatings not only were hydrophobic with the water contact angle greater than 130°, but also exhibited high heat resistance. Moreover, the hybrid nanocomposite could also be used as nano viscosity depressants for crude oil. The viscosity of crude oil could be reduced more than 80%. Owing to these good practical advantages, the PODMA/MPS/SiO2 hybrid nanocomposites may have some potential applications in practical industrial production.

Pneumocandin B0-imprinted Polymer Using Surface-imprinting Technique for Efficient Purification of Crude Product

In this work, we prepared surface molecularly imprinted polymer (MIP) for selective recognition of pneumocandin B0 (PNB0). Methacrylic acid (MAA) was first grafted onto silica gel particles (SiO2) in the manner of "grafting from" by using 3-methacryloxypropyl trimethoxysilane as intermedium, and then PNB0 molecules were imprinted on the surface of the obtained particles in the presence of ethylene glycol diglycidyl ether as the cross-linker. The prepared MIP-PMAA/SiO2 was characterized by scanning electron microscopy, Fourier transform infrared spectroscopy and thermo-gravimetric analysis, which confirmed the successful grafting of MAA onto SiO2 and the grafting degree was calculated to be 12.50 wt%. The binding properties of the products were investigated and it is found that the binding process of PNB0 followed the pseudo-second-order kinetic model. The as-prepared material also displays relatively quick adsorption kinetics and decent recognition affinity toward the template over its structurally related compound.

A composite monolithic column fabricated with functionalized nanodiamond and its application in separation of small molecules

A nanodiamond-based composite monolithic column was fabricated by redox initiation for high performance liquid chromatography (HPLC). The functionalized nanodiamond was modified via Fenton Reagent and 3-methacryl oxypropyltrimethoxysilane (KH-570). After being optimized conditions, composite monolithic columns were prepared with functionalized ND (f-ND) as functional monomer, dipentaerythritol hexaacrylate and ethylene dimethacrylate as crosslinking agents, dodecanol and 1-propanol as co-porogens, dibenzoyl peroxide and N,N-dimethyl aniline as initiators. Characterizations of the resulting nanocomposite, including fourier transform infrared spectra, scanning electron microscopy images, thermal gravimetric analysis, mercury intrusion porosimetry and nitrogen adsorption–desorption isotherm were all carried out in detail. Bigger specific surface area, better mechanical stability, thermostability property and orderliness skeleton structure with flow-through channels and macroporous of the composite monolithic column was exhibited than those columns without f-ND added. At last, the nanodiamond-based composite monolithic column was used to separate a series of small molecules including acidic, alkaline and neutral compounds with good resolution and reproducibility in HPLC.

One-Step Co-Intercalation of Montmorillonite with Cetyltrimethylammonium and Methacryloxy Propyl Trimethoxy Silane for Sensitive Determination of Indole-3-Acetic Acid with High Selectivity and Reproducibility

One-Step Co-Intercalation of Montmorillonite with Cetyltrimethylammonium and Methacryloxy Propyl Trimethoxy Silane for Sensitive Determination of Indole-3-Acetic Acid with High Selectivity and Reproducibility

Analysis of 3-methacryloxypropyl trimethoxysilane treated cenosphere inclusion on dynamic mechanical properties of ABS composites

Growth of Automobile industries and thrust for innovative materials led material developers to develop cost effective and property rich plastic composites particularly having good Dynamic Mechanical Properties. The present study deals with development of ABS composites by using 3-methacryloxypropyl trimethoxysilane (KBM-503) treated cenosphere (CS) as filler. In this study composites were prepared using co-rotating twin screw extruder with filler concentration 0–30 wt%. Injection molded specimens were prepared to analyze the effect of concentration of silane treated cenosphere on the dynamic mechanical properties of ABS composites. The structural characterization was analyzed by SEM instrument.

Thermoresponsive mesoporous silica nanoparticles as a carrier for skin delivery of quercetin

Recently, mesoporous silica nanoparticles (MSNs) have emerged as promising drug delivery systems able to preserve the integrity of the carried substance and/or to selectively reach a target site; however, they have rarely been explored for skin application. In this study, thermoresponsive MSNs, designed to work at physiologic cutaneous temperature, are proposed as innovative topical carriers for quercetin (Q), a well-known antioxidant. The thermosensitive nanoparticles were prepared by functionalizing two different types of matrices, with pore size of 3.5nm (MSNsmall) and 5.0nm (MSNbig), carrying out a free radical copolymerization of N-isopropylacrylamide (NIPAM) and 3-(methacryloxypropyl)trimethoxysilane (MPS) inside the mesopores. The obtained copolymer-grafted MSNs (copoly-MSNs) were physico-chemically characterized and their biocompatibility was attested on a human keratinocyte cell line (HaCaT). The release profiles were assessed and the functional activity of Q, free or loaded, was evaluated in terms of antiradical and metal chelating activities. Ex vivo accumulation and permeation through porcine skin were also investigated. The characterization confirmed the copolymer functionalization of the MSNs. In addition, both the bare and functionalized silica matrices were found to be biocompatible. Among the copolymer-grafted complexes, Q/copoly-MSNbig exhibited more evident thermoresponsive behavior proving the potential of these thermosensitive systems for advanced dermal delivery.

Radical scavenging efficiencies of silane-grafted carbon nanotubes and their effects on crosslinking reaction of vinyl ester/styrene resin

Carbon nanotubes (CNTs) that were first grafted with vinyl trimethoxysilane (VTMS) and then with methacryloxypropyl trimethoxysilane (MATMS) could result in well dispersion in thermosetting vinyl ester/styrene resin and exhibit significant enhancement in storage modulus of the composite. If the VTMS-grafted CNTs were grafted with VTMS, rather than MATMS, in the second step of grafting, significant phase separation was found in the composite. The scavenging efficiencies of the silane-grafted CNTs for hydroxyl (OH.) radicals measured by electron paramagnetic resonance (EPR) were investigated as a function of the step and degree of grafting. The EPR data revealed that the radical scavenging efficiency of a given CNTs exhibited a significant decrease after the first step of grafting with VTMS but exhibited insignificantly further decrease after the second step of grafting with MATMS. The radical scavenging efficiency of a given silane-grafted CNTs was decreased with increasing degree of the silane grafting, an indication that the radical scavenging mechanism involved the reactions of radicals with the CNTs, rather than with the silane grafts. The radical-initiated crosslinking of the vinyl ester/styrene composite was significantly retarded by the silane-grafted CNTs; this should be taken into consideration when producing thermoset polymer/CNT composites having highly enhanced moduli.

A study on water and oxygen permeability of BOPP coated with hybrid UV cured nanocoatings

Abstract This paper attempts to compare the effect of precursor ratio and content of inorganic and organic phases of sol-gel based hybrid UV cured coating on water and oxygen barrierity of biaxially oriented polypropylene (BOPP) substrates. To this end tetraethyl orthosilicate (TEOS) and 3 -methacryloxy propyl trimethoxysilane (MEMO) were used together with acrylate monomer and oligomers in different ratios. Water vapor transmission rate (WVTR) and oxygen transmission rate (OTR), were measured and discussed based on morphologies appeared. Hybrid coatings were successful to prevent water and oxygen permeation and reduced WVTR of uncoated BOPP from 12 to 0.96 g/(m 2 d). and oxygen transmission rate declined from 566 to 159 cm 3 /(m 2 d) in comparison with substrate. It was observed that in identical TEOS ratio to MEMO, by increasing the inorganic content permeability to oxygen and water vapor decreased. Also, in constant inorganic to organic ratio (I/O = 50), by an increase in the ratio of TEOS to MEMO from 20 to 80 water vapor depreciated from 2.5 to 0.96 g/(m 2 d). These results were in agreement with the degree of compactness of the networks as revealed by different analytical characterizations.

Influence of Silane Coupling Agent and Nano-Filler on the Properties of Dental Resin Composite Cements

Dental resin composite cements were prepared with simply mixing method of Part A and Part B. The material components in Part A were composed of Bis-GMA, TEDGMA, 4-META, SiO2 nanopowders and BPO. The components in Part B were Bis-GMA, TEDGMA, 4-META, SiO2 nanopowders and 2,2¢-(4-methylphenylimino) diethanol. Before using SiO2 nano-filler in the formulation of Part A and Part B, it had to be coated with methacryloxypropyltrimethoxysilane (MPS) which served as a silane coupling agent. Therefore, the optimum amount of MPS (1, 1.2, 1.5 and 2%) and SiO2 nano-filler (20, 27.27 and 33.33 wt%) used to fabricate the composites were investigated. The homogeneous mixture of Part A and Part B at mass fraction of 1:1 was formed into the bar shape with dimension of 25 mm x 2.0 mm x 2.0 mm and then cured under light source for 20 s. Then flexural strength was measured using the universal testing machine. Depth of cure was tested using mould which was perforated in cylindrical shape of 6 mm in depth and of 4 mm in diameter. The result showed that composite with 27.27 wt% of salinized SiO2 nanopowders by 1.5% of MPS showed the highest flexural strength of 65 MPa and depth of cure of more than 5 mm which were accepted according to ISO 4049. This study could be concluded that using a proper amount of MPS to silanize SiO2 nanopowders and using an optimum amount of SiO2 nanopowders significantly improved the flexural strength of dental resin composite cements.

Preparation and Evaluation of a Zirconia/Oligosiloxane Nanocomposite for LED Encapsulation.

A zirconia/oligosiloxane nanocomposite encapsulant has been developed and tested in a high-power LED package against commercial silicone resins. The composite was a marriage of zirconia nanocrystals modified with butyric acid (BA) and 3-methacryloxy propyl trimethoxysilane (MPTMS) and a high-index methacryloxy-oligosiloxanes resin made from MPTMS plus dimethyl, diphenyl, and triphenyl silanes. The modified zirconia had an index of 1.762 (@589 nm) and was dispersible in many solvents. The oligosiloxane resin, however, had an index of 1.5413 with good encapsulation properties and low viscosity allowing the incorporation of more zirconia. The final nanocomposite showed a refractive index of 1.625 with high transparency and a wavelength-independent scattering, both desirable for the light extraction from LED. When tested in a high-power LED package, the composite encapsulant resulted in 13% more light output compared to the commercial encapsulant (OE-6630, Dow Corning Corp.) and showed longer than 1000 h of lifetime (L70) under the steady-state Temperature Humidity Bias (THB) test.

Synthesis of waterborne polyurethane containing alkoxysilane side groups and the properties of the hybrid coating films

A series of waterborne polyurethane (WPU) containing alkoxysilane side groups were synthesized by using the dihydroxy functionalized alkoxysilane. The diol with trimethoxysilane groups at the side chains was synthesized via Michael addition between 3-(methacryloxypropyl)trimethoxysilane (MAPTS) and diethanolamine (DEA). The silane diol was applied as the chain extender for the NCO-endcapped prepolymer of isophorone diisocyanate, polycarbonate diol, 2,2-bis(hydroxymethyl) butyric acid and 1,4-butanediol. The products with the silane content varied from 1.2 to 16.5wt% were dispersed in water after neutralization. The effect of the silane diol on the particle size and morphology of the WPU dispersion was studied by dynamic light scattering (DLS) and transmission electron microscopy (TEM), respectively. X-ray photoelectron spectroscopy (XPS) characterization was carried out on the coating film of the WPU, revealing that the long flexible side chain is favorable for the silane components to emigrate toward the film surface and crosslink during the film formation process. As a result, both the surface contact angle to water and water adsorption of the WPU coating films increased with the silane content. Furthermore, the mechanical properties including the modulus and tensile strength of the films were also improved by the incorporation of silane diol.

Modification and characterisation of pre-hydrolysed silanes by acrylate utilizing sol–gel process

The paper focuses on development of inorganic–organic hybrid coatings synthesised by pre-hydrolysed sol of Vinyl trimethoxy silane (VTMS) and Methacryloxy propyl trimethoxy silane (MPTMS), which were modified at different mole ratios by butyl acrylate. The formed sols and hybrids were characterised by using Fourier Transform Infrared Spectrophotometer FTIR, Gel Permeation Chromatography (GPC) and Thermogravimetric Analysis (TGA) while the coatings formed using the hybrid resins were evaluated for their physical and chemical resistance using ASTM standards. The obtained results were used for comparing the two hybrid systems of VTMS and MPTMS sol synthesised by modification with butyl acrylate.

Mechanical interfacial adhesion of carbon fibers-reinforced polarized-polypropylene matrix composites: effects of silane coupling agents

Thermoplastic composites are used in a variety of applications such as mass transit, auto-motive parts, and military structures [1-6]. Their appeal compared to conventional materials such as aluminum, steel, and thermoset composites for these applications lies in their high specific strength, corrosion resistance, superior impact resistance, high toughness, and ease of recycling [1-7].In recent years, carbon fibers (CF) have been widely used as reinforcing materials in high performance composites. CF present several advantages, including high modulus and strength, good stiffness, and creep resistance [8-10]. Despite these advantages, the CF/ther-moplastic composites have unsatisfactory mechanical properties because CF have poor in-terfacial adhesion with most thermoplastic polymers due to their non-polar surface.The interfacial adhesion between reinforcing fibers and polymer matrices in composites is the controlling factor in obtaining optimum mechanical properties of composites [11-13]. To achieve good interfacial adhesion between CF and thermoplastic matrices, it is necessary to increase the surface polarity. In this light, increasing the surface polarity for van der Waals forces and hydrogen bonding can improve the interfacial adhesion. In efforts to increase the surface polarity of CF, various surface treatment techniques have been applied, including plasma treatment, anodic oxidation, metal plating, and cou-pling treatment [14,15]. Among the various treatments, coupling treatment is known to be a very effective method for improving the interfacial adhesion between the fibers and the thermoplastic matrices [16].The role of coupling agents in improving the interfacial adhesion between polymers and inorganic surfaces has been widely documented [17,18]. However, the effects of different coupling agents on interfacial adhesion between CF and polar-modified thermoplastic matri-ces have yet to be explicitly identified. Therefore, the first objective of this study is to evaluate the influence of sizing treatments by silane-based coupling agents on the interfacial adhesion properties between the fibers and the thermoplastic matrix. Another objective is to investigate the effects of the presence of surface functional groups containing silane-oxygen groups on the mechanical properties of carbon fiber-reinforced maleic anhydride-grafted polypropylene.The CF used in this work were polyacrylonitrile based high strength fibers, T-700SC-13000 (12K unidirectional fabric; Toray, Tokyo, Japan). The average diameter of these CF was around 7 μm. A highly polarized polypropylene sheet prepared by maleic anhydride grafting (Homan Petrochemical Co, Seoul, Korea) was used as a matrix. The reagents used for the coupling treatments were vinyltriethoxy silane (VTES), 3-ami-no propyl triethoxy silane (APS), and 3-methacryloxy propyl trimethoxy silane (MPTS; Aldrich, St. Louis, MO, USA), denoted as VTES, APS, and MPTS, respectively. The acid and silane treatments of the CF were carried out by the following procedure. For the acid

Preparation of Tetracycline Surface Molecularly Imprinted Material for the Selective Recognition of Tetracycline in Milk

Silica particles were modified with 3-methacryloxypropyl trimethoxysilane (MPS) as a carrier material. The tetracycline (TC) molecular imprinting polymer based on the surface of modified silica (MPS/SiO2) was prepared by adopting the novel surface molecular imprinting technique with tetracycline as template molecule and ethylene glycol diglycidyl ether (EGDE) as crosslinker. The rebinding capacity of molecularly imprinted polymer (MIP) was evaluated according to the adsorption kinetics and the adsorption isotherm. The two distinct linear portions in Scatchard analysis indicate that two classes of binding sites existed in the imprinted polymer. The MIP obtained was used as a selective sorbent for molecularly imprinted solid-phase extraction (MISPE) prior to HPLC analysis. The results showed that good linearity was observed in the range of 150∼950 μg/L for TC, with a correlation coefficient of 0.9972. Adding level of 300∼700 μg/L, the average of spiked recoveries of TC is about 81.1 %, with a relative standard deviation (RSD) range from 3.0 to 4.4 %, and the limit of detection (LOD) reached 25 μg/L. The proposed method is easy to operate, reliable, and applicable to analyze the TC residues in milk samples.

Enhancement of the anti-corrosion efficient of hybrid nanostructure coating using copper phthalocyanine self-assembled monolayers

A self-assembled films (SA) of cupper phthalocyanine (CuPh) chemisorbed on the mild steel surface was coated by an inorganic-organic sol gel hybrid coating. Hybrid sol was synthesized via acid catalyzed hydrolysis and condensation of methacryloxypropyl trimethoxysilane (TMSM) and tetraethoxysilane (TEOS) at the molar ratio of 1: 1. The morphology of mild steel coated with TMSM/TEOS and CuPh was examined by SEM. The surface chemistry of the hybrid sol-gel coatings was investigated with polarization scans and electrochemical impedance spectroscopy (EIS) in aerated 0.5 mol L–1 HCl solution. Self assembled CuPh films coated under the hybrid coating showed a strong influence on its corrosion resistance, mainly when the samples have 24 h immersion time and 1 mM concentration.

Composition, structure and morphology of hybrid acrylate-based sol–gel coatings containing Si and Zr composed for protective applications

Abstract The role is reported of zirconium tetrapropoxide (ZTP) and methacrylic acid (MAA), following their combination with sol synthesized from tetraethyl orthosilicate (TEOS) and 3-methacryloxypropyl trimethoxysilane (MAPTMS). The molar content of ZTP was varied between 0.06 and 0.96 and that of MAA between 0.12 and 1.92. The synthesized sols were deposited as coatings on aluminium substrates. The effects of ageing of sols and curing of the coatings were examined. The composition of the sol, ageing process and size distribution of the particles, the thermal stability of the sols and coatings, the phase composition and microstructure of the coatings and contact angle of the water drop at the coating surface were all investigated. Comparison of sols, using Fourier transform infrared spectroscopy, confirmed important differences in terms of the presence of Si–O–Zr and chelated ZTP–MAA bonds. The three sols studied differ significantly in their ageing behaviour, as shown by dynamic light scattering. Thermogravimetric analysis and analysis of vapour side products during the curing process confirmed the effect of sol composition on the mass loss at elevated temperatures. Morphology, phase composition and structure of the coating were analysed with scanning and transmission electron microscopy, atomic force microscopy and X-ray diffraction analysis. The coatings possess a homogeneous and amorphous structure, without the formation of nanoparticles. Synthesized coatings offer high corrosion protection of aluminium under simulating aircraft conditions.