• Membrane Journal
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• v.17 no.1
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• pp.44-53
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• 2007

The primary objective of this study is to increase the extent of water flux and fouling resistance of nano-filtration or reverse osmosis membranes. This study was performed to investigate the effect of surface characteristics of silane coated membranes on modified fouling index. Commercial polyamide composite RO membrane (RE1812-LP) and NF membrane (ESNA4040-LF) were treated with silane coupling agents in ethanol at five different concentrations. The silane coupling reagent, aminopropylmethoxydiethoxysilane, contains one aminoalkyl and three alkoxy groups. The hydrophilic effect of aminoalkyl group of APMDES on the permeability and fouling resistance of the modified membrane was examined. The surfaces of the modified membranes were characterized by FE-SEM, contact angle analyzer, and zeta potentiometer in order to confirm successful sol-gel methods. The modified NF membranes showed significantly enhanced water flux and fouling resistance without a decrease in salt rejection in divalent ionic feed solution.

• Polymer(Korea)
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• v.30 no.4
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• pp.318-325
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• 2006

Polypropylene-clay nanocomposites were studied by the modification of clay with amino silanes to introduce covalent bonds in nanocomposites, and prepared by melt-compounding with polypropylene, clay modified with amino silanes and maleic anhydride grafted polypropylene. The . .structure and surface properties of modified clay were determined by x-ray diffraction, infrared spectrum, and solid-state $^{29}Si$ nuclear magnetic resonance spectrum. The modification of clay with aminosilanes led to the increase of the silicate interlayers to about $19.8{\AA}$, the weakening effects of hydroxy group at $3650cm^{-1}$ and the signal of amine groups at -69 ppm proved that the modification had taken place.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.9 no.1
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• pp.1-11
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• 2011

Tetraethoxysilane(TEOS) as a silica precursor and hydrochloric acid as an acid catalyst have been used in a surfactant-template synthesis of micrometer-sized mesoporous silica microspheres based on the macroemulsion technique. Increase in the concentration of tetraethoxysilane of the reaction mixture has a serious destructive effect on the particle shape and pore structure. As the acid concentration increases, relatively small microspheres are formed without destroying their spherical morphology of the particles as well as the pore structures. However, due to the attractive interaction between particles in an acidic condition, strong silica agglomerates are formed, and therefore are subject to a post-ultrasonic treatment to separate into an individual single particle.

• Elastomers and Composites
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• v.36 no.4
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• pp.237-245
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• 2001

A study was made on the chemical treatment of silica and silane coupling agents, bistriethox ysilylpropyltetrasulfide(Si 69) and ${\gamma}$-mercaptopropyltrimethoxy silane (MPS) for reinforcement of silica formulation. The effects of chemical treatment method and the most popular two coupling agents were examined. The results clearly indicate that the wet method, coupling agent is combined chemically with the silica prior to mixing, has more dispersion, wetting ability, dynamic properties and stability than the dry method, coupling agent is premixed directly with the silica. The mixing was done using a bench-type kneader having two mixing cam and a two-roll mill, under approximately similar conditions. The physical properties of SBR vulcanizates give rise to marked improvements by addition of Si 69 and MPS in comparison with without silane coupling agents. The optimum amount of Si 69 and MPS was 2 w/w% by experiments in the dry method but was 4 w/w% by EA and TGA analysis in the wet method.

• Applied Chemistry for Engineering
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• v.1 no.1
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• pp.63-72
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• 1990

Surface of crystalline silica was sequentially reacted with silane(A 187), liquid rubber(CTBNx8) and vinyl monomer(AA, MMA, 2-HEA, GMA) in existance of amines(TEA, CTMAB, BETAC) or peroxide(BPO). By mixing it with epoxy resin at a ratio 0~36%(volume %) of total component, liquid properties of mixtures was investigated experimentally. i) Coating ratio depended on quantity and sorts of catalyst. ii) Total coating of 2.5~5.8% was attained by using 0.1~2.0% of catalyst. iii) Treated surfaces represented each different features in according to sorts of treatment. iv) Silane/rubber or silane/rubber/vinyl represented lower viscosity and settling than non-treated or silane-treated.

• Journal of the Korean Applied Science and Technology
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• v.33 no.1
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• pp.168-175
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• 2016

The surface of glass fiber bundle was modified with functionalized silanes and phenolic resin to improve the tensile strength as well as the adhesion of glass fiber to matrix phenolic resin. The surface modification of reinforcing glass fiber can play a significant role in controlling whole composite characteristics. We applied surface modification of glass fiber with two different functionalized silanes, such as glycidyltrimethoxysilane(G-silane) and aminopropyltriethoxysilane (A-silane), and phenol formaldehyde(PF) resin in one pot or separated process under different coating compositions and temperatures. Thermal treatment temperature is very important factor to improve the mechanical properties of modified glass fiber. Modified glass fiber bundle treated at $170^{\circ}C$ showed the highest tensile strength of $10.05g_f/D$. Surface analyses by scanning electron microscope(SEM) and FT-IR spectroscopy were used to characterize the surface coatings on glass fiber bundles. Mechanical property changes as functions of treatment conditions and coupling agent types were also explained.

• Composites Research
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• v.24 no.6
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• pp.18-24
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• 2011

The effect of surface treatments with the atmospheric pressure flame plasma (APFP) and epoxy silane (ES) is experimentally investigated to yield the best mechanical properties of silica ($V_f=40%$) reinforced elastomeric composites. The tensile strength of the composites is increased significantly with decrease the mean diameter. When the diameter is $2.2{\mu}m$, that of the composite is increased about 1.4 times compared to the matrix (2.52 MPa). Also, the tensile strength of silica reinforced composites with APFP and ES treated is increased 8.8~13.3%, 9.9~12.5%, respectively. When the diameter is $26.6{\mu}m$, the tensile modulus of the composite is increased about 2 times compared to the matrix (0.88MPa), and the tensile modulus of silica reinforced composites with APFP and ES treated is increased 15.6~22.8%, 21.1~5.8%, respectively. Conventional silane coupling agent treatment have a few disadvantages because of using organic solvents. However APFP treatment is a fast, economic and eco-friendly method to improve the mechanical properties.

• Elastomers and Composites
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• v.34 no.1
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• pp.53-64
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• 1999

The mechanical, electrical, and thermal properties of polyamide-modified poly (vinyl chloride) (PVC)-sol was investigated. PVC-sol was plasticized with dioctyl phthalate (DOP). In this work, the effects of the addition of polyamide on the properties of PVC-sol seal-ants were investigated. Two kinds of polyamide resins having different amine value were used. It was found that the properties of the PVC-sol sealants were significantly affected by the contents and types of the added polyamide rosins. The PVC-sol sealants modified with polyamide A (low amino value) showed higher tensile properties than those modified with polyamide B(high amino value) did, and thermal stability of the sealants showed nearly the same trends. The tensile strength of sealants were decreased with increasing the $CaCO_3$ contents. The dielectric constant were not strongly dependent on the polyamide types and contents.

• Polymer(Korea)
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• v.38 no.6
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• pp.787-790
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• 2014

In this work, the epoxy specimens were prepared from diglycidyl ether of bisphenol F (DGEBF) with silane coupling agents (3-glycidoxypropyl trimethoxysilane (GPTMS)) in different ratios. Thermal stability was studied in terms of polymer decomposition temperature (PDT), temperature of maximum rate of weight loss ($T_{max}$), integral procedural decomposition temperature (IPDT), and decomposition activation energy ($E_a$) using TGA analysis. Adhesion properties of epoxy composite specimens were measured by UTM (universal testing machine) at atmosphere temperature. In this result, the adhesion properties of DGEBF were improved by addition of silane coupling agents compared to non-treated epoxy resin. However, when the content of GPTMS agent is more than 10 phr, adhesion properties decreased with increasing GPTMS agent.

• Polymer(Korea)
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• v.35 no.4
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• pp.302-307
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• 2011

The parameters of silanol formation reaction of organosilane including solvent type, solution concentration, pH and hydrolysis time influence the adhesion property of 2 layer flexible copper clad laminate (FCCL). Especially, the hydrolysis reaction time of silane coupling agent affects the formation of the silanol groups and their self-condensation to generate oilgomeric structure to enhance the surface treatment as an adhesive promoter. In our study, we prepared the binary silane coupling agents to control hydrolysis reaction rate and surface energy after treatment of silane coupling agents for increasing the adhesive property between a copper layer and a polyimide layer. The surface morphology of rolled copper foil, as a function of the contents of the coated binary silane coupling agent, was fully characterized. As fabricated 2-layer FCCL, we observed that adhesive properties were changed by hydrolysis rate and surface energy.