Trimethoxysilyl Propyl Methacrylate Research Articles

In-situ surface modification of a reverse osmosis membrane with acrylic polymers: Transport and retention of a small neutral organic micropollutant

Highly selective in-situ surface grafting approaches were designed to improve the rejection of 1H-benzotriazole (BTA) by a reverse osmosis (RO) membrane. A commercial FT30 membrane was grafted in-situ for the first time with 2-(diethylamino)ethyl methacrylate (DEAEMA) and 3-(trimethoxysilyl)propyl methacrylate (TMSPMA), respectively, and compared with the state-of-the-art polydopamine (PDA) modification method. The TMSPMA grafting enhanced the BTA rejection from 88.4% to 98.4%, with a minor drop in water permeability (0.3%) compared to the pristine membrane. The FT30-TMSPMA membrane performed considerably better than the FT30-DEAEMA and FT30-PDA membranes. The improved rejection after TMSPMA modification can be ascribed to enhanced steric exclusion and hydrophobic interactions. The boosted hydrophobicity of the FT30-TMSPMA membranes is the result of the hydrophobic nature of the propyl/methyl groups present in TMSPMA, resulting in an 11.3% and 8.8% higher selectivity of BTA compared to the pristine FT30 and FT30-PDA membrane, respectively. The A/B ratio (which indicates the membrane selectivity to water against the solute) of the FT30-TMSPMA membrane increased by 714%, which is the highest enhancement compared to other modified materials reported in the literature until now. This new modification approach is thus highly promising for membrane functionalization to improve the rejection of small neutral organic micropollutants.

Melamine‐imprinted quartz crystal microbalance sensor for its detection in milk

AbstractA unique and selective molecularly imprinted polymer (MIP) was fabricated to detect melamine using a quartz crystal microbalance (QCM) surface. The MIP was synthesized by sol–gel technique utilizing 3‐(trimethoxysilyl) propyl methacrylate (TMSPMA) as the functional monomer bearing the methacrylate head group. To identify the melamine, we applied a coating of the as‐synthesized MIP over the silicon crystal of the quartz crystal microbalance (QCM) detector. High‐affinity adsorption of template molecules from the aqueous solution is the basis of the detection. Adsorption experiments performed in real‐time on MIP surfaces indicate that melamine forms strong bonds with its template molecule. We have evaluated the MIP surface using contact angle, BET, RAMAN and AFM investigations regarding wettability, reactivity, surface area, and smoothness. The real‐time adsorption experiments of template molecules on the MIP substrate reveal enhanced attachments with MIP, whereas the NIP demonstrates no interactions with the template molecules. Melamine detection in tainted milk samples further validated the MIP QCM sensor effectiveness. Melamine at a concentration ranging from 1–20 mg/L is tested. Findings conclude that the polymerization method and the QCM nanosensor for selective melamine detection were adequate substitutes for the technologies currently used for detecting melamine.

Enhancing anticorrosive performance of epoxy‐based ZnO nanocomposite coatings via 3‐(trimethoxysilyl)propyl methacrylate modification

AbstractThe influence of 3‐(trimethoxysilyl)propyl methacrylate (TMSPM) on the properties of epoxy‐based ZnO nanocomposite coatings was investigated, considering its impact on both modified ZnO nanoparticles (NPs) and epoxy resin matrix. FTIR analysis revealed that TMSPM‐modified epoxy resin (mEP) exhibited lower hydroxyl group and epoxy group content compared to the initial epoxy resin (EP). Furthermore, the obtained results demonstrated that epoxy‐based coatings incorporating modified ZnO NPs (m‐ZnO NPs) displayed superior mechanical properties compared to those of the sample filled with the unmodified ZnO NPs (u‐ZnO NPs). However, the mechanical properties of epoxy‐based coatings loaded with m‐ZnO NPs were found to be lower than those of coatings comprising mEP resin and m‐ZnO NPs. The arrangement of anticorrosion performance of coatings followed a similar pattern. SEM analysis of the cross‐cut surface revealed better dispersion of m‐ZnO NPs compared to the u‐ZnO NPs, although small gaps were observed among the m‐ZnO NPs and the epoxy matrix. The SEM images of coatings based on mEP and m‐ZnO NPs indicated a tighter structure. This structural characteristic is considered the main reason for the highest anticorrosion performance observed in the investigated coatings incorporating both mEP and m‐ZnO NPs.

SiO2@Al2O3 binary filler: A chance for enhancing the heat transport in rubber composites for tire applications

AbstractThe present study reports on the development of a new binary filler system for rubber composites, SiO2@Al2O3, where Al2O3 sheets are grown onto SiO2 nanoparticles aggregates by a sustainable water‐based soft‐chemistry approach. The aim is to synergistically integrate the intrinsic thermal conductivity properties of Al2O3 with the peculiar reinforcement ability of SiO2 in an easy one‐pot solution, which has been exploited to prepare polybutadiene (PB) model composites by a simple solvent casting technique. More in detail, the binary filler was used as‐prepared or suitably surface functionalized with 3‐(Trimethoxysilyl)propylmethacrylate (TMSPM). The filler compatibilization and interplay with the polymeric matrix have been inspected by solid state NMR in conjunction with scanning electron microscopy. These investigations highlighted that the presence of alumina in the binary filler does not undermine the capability of silica in generating polymer chains stiffening and indicated a significant effect of the silanization in providing better filler networking and interaction with the PB host ensuring, in principle, an enhanced thermal transport. Accordingly, thermal conductivity measurements revealed that SiO2@Al2O3 introduction in PB induces a remarkable upgrade of the heat transfer, which becomes much more relevant upon surface modification with TMSPM. These results appear encouraging, paving the possibility of applying SiO2@Al2O3 model system to more complex case studies, where both improved thermal conductivity and enhanced reinforcement are required, such as tires tread formulations.Highlights A new SiO2@Al2O3 binary filler system was proposed following a soft‐chemistry approach. The binary filler was functionalized to enhance its compatibilization. Fillers were dispersed in polybutadiene by a simple solvent casting technique. Thermal conductivity measurements revealed a remarkable upgrade of the heat transfer ability.

Fabrication of a robust zwitterionic coating on glass with anti-fogging, anti-frosting, self-cleaning and antibacterial properties via UV-induced grafting polymerization

In this work, glass slides were separately silanized by silane coupling agents, 3-(trimethoxysilyl) propyl methacrylate (TPM) and 3-(mercaptopropyl) trimethoxysilane (MPS). Then, in presence of a photoinitiator, multifunctional hydrophilic coatings were fabricated facilely on these silanized glasses via UV-induced grafting polymerization of zwitterionic acrylic monomer methacryloxyethyl sulfobetaine (SBMA). The results showed that both TPM and MPS silanized glasses could participate in the UV-induced grafting polymerization of SBMA, while more SBMA could be grafted to the former glass to gain a little bit higher hydrophilicity. The structure, morphology and properties of the multifunctional glasses were investigated fully. As the hydrophilic polymer brushes poly(SBMA) (pSBMA) covalently attached to the glass surface, the glasses could render a series of excellent performances, including underwater superoleophobicity, anti-fogging, anti-frosting, abrasion resistance, self-cleaning and antibacterial adhesion, and especially high stability even after being immersed in water for 20 days. The strong interaction of pSBMA and water was confirmed via differential scanning calorimeter (DSC) and Raman spectrum analysis, to explicit the anti-fogging mechanism. Therefore, it is promising that the scalable multifunctional glass fabricated via UV-induced grafting polymerization could be potentially applied in the fields of automobile, bathroom, medical, etc.

Cosolvent incorporation modulates the thermal and structural response of PNIPAM/silyl methacrylate copolymers.

Polymers functionalized with inorganic silane groups have been used in wide-ranging applications due to the silane reactivity, which enables formation of covalently-crosslinked polymeric structures. Utilizing stimuli-responsive polymers in these hybrid systems can lead to smart and tunable behavior for sensing, drug delivery, and optical coatings. Previously, the thermoresponsive polymer poly(N-isopropyl acrylamide) (PNIPAM) functionalized with 3-(trimethoxysilyl)propyl methacrylate (TMA) demonstrated unique aqueous self-assembly and optical responses following temperature elevation. Here, we investigate how cosolvent addition, particularly ethanol and N,N-dimethyl formamide (DMF), impacts these transition temperatures, optical clouding, and structure formation in NIPAM/TMA copolymers. Versus purely aqueous systems, these solvent mixtures can introduce additional phase transitions and can alter the two-phase region boundaries based on temperature and solvent composition. Interestingly, TMA incorporation strongly alters phase boundaries in the water-rich regime for DMF-containing systems but not for ethanol-containing systems. Cosolvent species and content also alter the aggregation and assembly of NIPAM/TMA copolymers, but these effects depend on polymer architecture. For example, localizing the TMA towards one chain end in 'blocky' domains leads to formation of uniform micelles with narrow dispersities above the cloud point for certain solvent compositions. In contrast, polydisperse aggregates form in random copolymer and PNIPAM homopolymer solutions - the size of which depends on solvent composition. The resulting optical responses and thermoreversibility also depend strongly on cosolvent content and copolymer architecture. Cosolvent incorporation thus increases the versatility of inorganic-functionalized responsive polymers for diverse applications by providing a simple way to tune the structure size and optical response.

Chemical functionality of surfaces for the characteristic adsorption of melamine

The surface functionality leading to a high reversibility adsorption of melamine was determined. Four different silane coupling agents, namely, 3‐(tri‐methoxysilyl) propyl methacrylate (TMSPMA), n‐propyl tri‐methoxy‐silane (PTMS), 3‐(tri‐ethoxysilyl) propionitrile (TESPN), and tri‐methoxy‐(octadecyl) silane (OTMS) were taken for making chemical functionality methacrylate, short methyl, nitrile, and extended methyl group respectively. The adsorption behavior of melamine over the substrates with four functionalities was determined using quartz crystal microbalance (QCM). The adsorption kinetics and adsorption isotherms of the adsorption studies were analyzed. The initial adsorption rate depends on the hydrophobicity and roughness of the surfaces. However, the subsequent adsorption rate depends on the specific interaction. The data of equilibrium adsorbed mass at various equilibrium concentrations were fitted with the modified Brunauer–Emmett–Teller (BET) and Freundlich adsorption isotherms. The estimated model parameters were analyzed and compared with the reported parameters of the relevant systems. There is good agreement between our results and the reported results. In addition, very high adsorption with a very high binding constant was observed for the adsorption of melamine OTMS surface. On the other hand, high adsorption with an intermediate layer binding constant for the adsorption of melamine on the methacrylate surface was observed. Based on this, we propose using acrylate chemical functionality to develop molecularly imprinted polymer‐based melamine sensors.

A surface treatment method for improving the attachment of PDMS: acoustofluidics as a case study

A method for a permanent surface modification of polydimethylsiloxane (PDMS) is presented. A case study on the attachment of PDMS and the lithium niobate (LiNbO3) wafer for acoustofluidics applications is presented as well. The method includes a protocol for chemically treating the surface of PDMS to strengthen its bond with the LiNbO3 surface. The PDMS surface is modified using the 3-(trimethoxysilyl) propyl methacrylate (TMSPMA) silane reagent. The effect of silane treatment on the hydrophilicity, morphology, adhesion strength to LiNbO3, and surface energy of PDMS is investigated. The results demonstrated that the silane treatment permanently increases the hydrophilicity of PDMS and significantly alters its morphology. The bonding strength between PDMS and LiNbO3increased with the duration of the silane treatment, reaching a maximum of approximately 500 kPa. To illustrate the effectiveness of this method, an acoustofluidic device was tested, and the device demonstrated very promising enhanced bonding and sealing capabilities with particle manipulation at a flow rate of up to 1 L/h by means of traveling surface acoustic waves (TSAW). The device was reused multiple times with no fluid leakage or detachment issues. The utility of the presented PDMS surface modification method is not limited to acoustofluidics applications; it has the potential to be further investigated for applications in various scientific fields in the future.

Tightly anchoring bone‐like coating on the surface of titanium implants with complex three‐dimensional geometry through radical polymerization

AbstractBiological fixation of a Ti implant demonstrates significant advantages over conventional physical fixation. Modifying the surface of Ti implants with hydroxyapatite (HAp) coating has proven to be a promising strategy to enhance their bone integration capability in vivo. The currently reported strategies are confronted with the following problems: (i) low interfacial bonding strength and poor structural stability under mechanical force; (ii) being incapable of encapsulating Ti implants with complex 3D geometry; (iii) complicated processing procedures and high processing costs. Here, we fabricated a bone‐like polyacrylamide/poly(vinyl alcohol)/HAp (PAAm/PVA/HAp) coating on the surface of Ti implants with complex 3D geometry through thermal induced in situ radical polymerization of pre‐adhered vicious acrylamide/PVA/HAp (AAm/PVA/HAp) emulsion. Covalent interaction between the Ti matrix and the coating was constructed through incorporating vinyl groups on the surface of Ti matrix using 3‐(trimethoxysilyl)propyl methacrylate (TMSPMA). The as‐prepared coating demonstrated a record high shear bonding strength of 144.5 MPa and 75.50 MPa in dry and moist states, respectively. In addition, its interfacial toughness reached to 1.27 kJ/m2, while its maximum motion under shear mechanical force was only 0.64 mm (moist state). Anti‐fatigue tests (approximate 100% toughness retention rate at displacement of 0.1 mm) and degradation experiment exhibited the long‐term mechanical/structural stability of the coating in a in vivo environment. BMSCs co‐culture assay demonstrated the superior cytocompatibility and osteogenic property of the coating. In sum, this work provided a simple and cost‐effective strategy to construct homogeneous and tightly anchored HAp coating on the surface of Ti implants with complex 3D geometry.Highlights Homogeneous coating on Ti surface with bone‐like composition and structure. Being capable of encapsulating Ti implants with complex 3D geometry. Record high interfacial bonding strength/toughness. long‐term structural/mechanical stability in a moist environment. Superior biocompatibility and osteogenic property.

Methacrylate Silatrane: New Building Block for Development of Functional Polymeric Coatings through Controlled Silanization.

Organosilicons are prevalent for the development of nanostructures, adhesives, fillers, and surface functionalization due to their ease of operation, availability, and effective modification on various surfaces. 3-(Trimethoxysilyl) propyl methacrylate (TMSPMA) is a widely used commercial silane for designing hybrid polymers via radical polymerization for a wide spectrum of applications. However, the chemical stability and processibility of TMSPMA encounter burdens due to its susceptibility to hydrolysis and aggregation, resulting in limiting its functionality and implementations. In this work, methylacrylate silatrane (MAST) was newly developed to bear a chemically stable tricyclic caged silatranyl ring and a transannular N → Si dative bond for excellent stability, processability, and progressive deposition. A complete, uniform, and thin assembled adlayer of MAST on a silicon wafer was verified by a contact angle goniometer, ellipsometry, atomic force microscopy, X-ray photoelectron microscopy, and Fourier transform infrared spectroscopy. The good homogeneity and molecular orientation of the MAST coatings are attributed to controlled silanization on oxide surfaces and strong intermolecular hydrogen bonds between internal urea groups. Moreover, the zwitterionic monomer of 2-methacryloyloxyethyl phosphorylcholine (MPC) was employed to copolymerize with MAST or TMSPMA to afford macromolecular modifiers of p(MPC9-co-MAST1) and p(MPC9-co-TMSPMA1), respectively, for surface modification and antifouling properties on silicon substrates. p(MPC9-co-MAST1) well preserved the reactivity of the silatrane groups after the polymerization process, whereas the hydrolysis of silane groups of p(MPC9-co-TMSPMA1) obviously occurred, giving rise to aggregation of polymer chains. Therefore, the p(MPC9-co-MAST1) film on surfaces exhibited superior wettability, grafting density, and antifouling properties compared to p(MPC9-co-TMSPMA1). Accordingly, we envision the great potential of the MAST building block for the development of functional hybrid polymers, well-defined polymeric thin films, and nanomaterials.

One-pot synthesis of dual-sites adsorbent based on recycling spent Lithium-ion batteries: Matter cycle, orderly grafting, and copper adsorption

Waste carbon residue (WCR), a hazardous solid waste discharged from spent lithium-ion batteries recovery industry, have caused serious environmental pollution. In this work, WCR with ferric impurity was recycled as dual-sites adsorbents for efficient removal of Cu2+ in wastewater. The adsorbent, sulfhydryl grafting Fe(OH)3/graphite (SFG), was synthesized by one-pot method. In this process, the ferric impurity was transformed into amorphous Fe(OH)3 in-situ, and sulfhydryl (-SH) was orderly grafted on adsorbent surface by regulation of 3-(Trimethoxysilyl) propyl methacrylate (TPM). In the regulation, TPM combined adsorbent surface and cysteine molecule by its inorganic and organic ends. Furthermore, the filtrate and adsorbent could be reused many times. The adsorption kinetics followed the pseudo-second-order model, the isotherm fitted better with the Freundlich isotherm model, which indicated that the adsorption of Cu2+ on SFG was a multilayer and heterogeneous chemisorption process. Langmuir maximum adsorption capacity of Cu2+ was 185.2 mg/g which was higher than many similar adsorbents. Adsorption mechanisms were explored by material characterizations and DFT calculations. The –OH groups of Fe(OH)3 reacted with Cu2+ via ion-exchange, the sulfur atom in –SH groups chelated with Cu2+ by transferring electrons to Cu atom. Synergistic effect of Fe(OH)3, sulfhydryl, and TPM provided SFG with outstanding adsorptive performance to Cu2+ contamination.

Rheometeric, ultrasonic and acoustical shielding properties of Cu-alloy/silicone rubber composites for electronic applications

Silicone rubber (SR) is a highly adaptable material that is attractive for a variety of applications, including electronics, construction, and aerospace. In general, adding Cu-Al-Zn alloy to the SR matrix improved the mechanical properties of rubber composites and noise attenuation. The mechanical, magnetic, ultrasonic, and acoustic characteristics of the resulting SR-composites were characterized. According to variations in treated Cu-alloy loading, ultrasonic measurements were performed as the ultrasonic velocities, Poisson’s ratio, Young’s modulus, acoustic impedance, ultrasonic attenuation coefficient, and micro-hardness. Results indicated that adding treated Cu-alloy to SR-composites improves them significantly. They showed that curing time decreases gradually, tensile strength increases constantly and elongation at break of SR-composites has maximum value at 15% treated Cu-alloy. The coupling agent 3-(Trimethoxysilyl) propyl methacrylate (TMSPM) improves the mechanical properties of the composites by forming a network structure in the SR matrix and enhancing the interfacial interaction between the Cu-alloy and the SR matrix. The acoustic sound absorption coefficient, reflection coefficient, and damping factor calculations were studied in addition to the decibel drop ranging from 0.4–4.9 dB. The composite sample SR-4 is considered to have the optimal percentage of the selected acoustic properties studied. Thus, the shielding efficiency of SR-composite increased with increasing content of Cu-alloy which makes it applicable in ear plugs and electronic applications.

Synthesis and Characterization of Zirconia-Silica PMMA Nanocomposite for Endodontic Implants.

This study aimed to enhance the mechanical properties of PMMA composites by introducing various types of fillers, including ZrO2, SiO2, and a mixture of ZrO2-SiO2 nanoparticles, which were prepared as prototypes for an endodontic implant. The ZrO2, SiO2, and mixed ZrO2-SiO2 nanoparticles were synthesized using the sol-gel method and the precursors Tetraethyl Orthosilicate, Zirconium Oxychloride, and a mixture of both precursors, respectively. Before polymerization, the as-synthesized powders were subjected to the bead milling process to obtain a well-dispersed suspension. Two scenarios for the fillers were implemented in the preparation of the PMMA composite: a mixture of ZrO2/SiO2 and ZrO2-SiO2 mixed with two different types of silane: (3-Mercaptopropyl) trimethoxysilane (MPTS) and 3-(Trimethoxysilyl) Propyl Methacrylate (TMSPMA). The observation of the characteristics of all of the investigated fillers included the use of a particle-size analyzer (PSA), a Zeta-potential analyzer, FTIR, XRF, XRD, and SEM. The mechanical properties of the MMA composites, as prepared under various scenarios, were observed in terms of their flexural strength, diametrical tensile strength (DTS), and modulus of elasticity (ME). These levels of performance were compared with a PMMA-only polymer. Each sample was measured five times for flexural strength, DTS, and ME. The results showed that the best PMMA composite was SiO2/ZrO2/TMSPMA, as revealed by measurements of the flexural strength, DTS, and ME corresponding to 152.7 ± 13.0 MPa, 51.2 ± 0.6 MPa, and 9272.8 ± 2481.4 MPa, which are close to the mechanical properties of dentin. The viability of these PMMA composites, as measured up to day 7, was 93.61%, indicating that they are nontoxic biomaterials. Therefore, it was concluded that the PMMA composite created with SiO2/ZrO2/TMSPMA can be considered to be an acceptable endodontic implant.

Processing of 3-(Trimethoxysilyl)propyl Methacrylate (TMSPM) Functionalized Barium Titanate/Photopolymer Composites: Functionalization and Process Parameter Investigation

To improve the performance of lead-free piezoelectric composites, the functionalization of the filler particles has been suggested as a successful strategy in several recent reports. The details of the functionalization process, however, are not clear, nor is its influence on the dielectric properties of the composites. This study reports a systematic investigation of the functionalization process parameters of barium titanate nanoparticles (BTONP) with 3-(trimethoxysilyl)propyl methacrylate (TMSPM) used as a linker to an acrylate-based matrix polymer. Functionalization process temperature, time, functionalization agent ratio, solvent, and catalyst influence on the functionalization degree were measured by thermogravimetric analysis (TGA), elemental analysis, and Fourier-transform infrared (FTIR) spectroscopy. Elevated temperature and average functionalization time led to the highest functionalization degree in the form of a TMSPM monolayer on the particle surface. Three solvents, with and without catalysts, were investigated and two types of functionalized BTONP were selected for composite manufacturing. To this end, the functionalized particles were used to manufacture 10 vol.% BTONP/photopolymer UV light-curable composite suspensions. After solidification of the suspensions by exposure to UV light, the microstructure and dielectric properties of the resulting composites were investigated. It was seen that functionalization improves the dispersion of particles, increases suspension viscosity, and decreases the curing depth and dielectric properties.

A Janus membrane doped with carbon nanotubes for wet-thermal management.

In a human skin-fibrous fabric-external environment, fibrous materials, as the "second skin" of the human body, provide comfort against the wet and heat effectively. Fibrous materials protect human health and guarantee work efficiency in various outdoor or inner scenes. Personal wet-thermal management based on fibrous materials can regulate comfort in a facile manner with low or zero energy consumption, which has become a potential development area. However, realizing synergistic management of the wet and heat effectively and conveniently is a challenge in the development and production of fibrous materials. We designed and fabricated a Janus fibrous membrane composed of 3-(trimethoxysilyl)propyl methacrylate (TMSPMA)-modified hydrophobic cotton gauze and electrospun carbon nanotubes (CNTs)-doped cellulose acetate (CA) hydrophilic fibrous membrane. Taking advantage of asymmetric wettability along its thickness direction, the Janus fibrous membrane, acting as a "liquid diode", could transport sweat/moisture from human skin to the external environment unidirectionally, which endowed a dry surface on human skin, avoiding "stickiness", and realizing wet management. Doped CNTs had good photothermal-conversion capacity, so the Janus membrane exhibited excellent heating capacity for passive radiation, so excellent synergistic wet-thermal management was obtained. The Janus membrane could be a candidate for diverse applications of fibrous membranes. Our data provide new ideas for the design and fabrication of fibrous membranes with remarkable wet-thermal management.

An Evaluation of Immobilized Poly-(S)-N-(1-phenylethyl)acrylamide Chiral Stationary Phases

In this study, brush type and polymer type stationary phases were prepared based on (S)-N-(1-phenylethyl) acrylamide, and the polymeric stationary phase demonstrated superior chiral recognition ability. The two polymeric stationary phases were synthesized by two strategies, one was the “grafting from” method, which obtained polymer CSP by initiating monomer polymerization on the surface of 3-methacrylatepropyl silica gel, and the other was “grafting to”, which fixed the copolymer of (S)-N-(1-phenylethyl) acrylamide and trimethoxysilylpropyl methacrylate on silica gel. A comparison of these two bonding modes revealed that the stationary phase produced by “grafting to” had higher chiral recognition ability. Further improvement can be achieved by the end-capping of silanol groups with trimethylchlorosilane to reduce non-enantioselective retention caused by residual silanol groups and improve the peak shape of enantiomers. Chiral separation in subcritical fluid chromatography was also studied. Similar enantioselectivity results with higher resolution were observed due to the improvement of peak shape.

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.

Specific interaction through functional group and molecularly imprint-based QCM-D sensor for detection of phorate and malathion

The molecularly imprinted polymer (MIP) is used to detect organophosphate pesticides phorate and malathion. The sol-gel technique is used to synthesize the MIP using 3- (trimethoxysilyl) propyl methacrylate (TMSPMA) as a functional monomer. We have coated the silica crystal of the quartz crystal microbalance (QCM) sensor with the synthesized MIP to detect the pesticides. The detection is based on the specific high adsorption for template molecule from solution. The real-time adsorption studies of the pesticides on MIP surfaces show their significant binding with the respective pesticide used as a template molecule. However, the adsorbed mass of the pesticides on the MIP of the pesticides is verified by using the concentration depletion method. The concentration of the pesticides was measured using high-performance liquid chromatography. The adsorption data matches well with the data obtained using QCM. The specificity and repeatability experiments indicate that the developed MIP is highly selective for the studied pesticides. The obtained selectivity of malathion and phorate are 9.4 and 6.8, respectively, and indicative of the goodness of the developed material.

The surface chemical functionality and diffusion mediated adsorption of organophosphates from their low concentration

The detection and removal of pesticides from their very low concentration solution are daunting tasks. The development of substrates leading to the adsorption of the pesticides requires a thorough understanding of the adsorption process. Here, we studied the interaction of two organophosphates, phorate, and malathion, on functionalized by using four different silane coupling agents, namely n-propyltrimethoxy silane (PTMS), octyltrimethoxy silane (OTMS), 3- (trimethoxysilyl) propyl methacrylate (TMSPMA) and 3- (triethoxysilyl) propionitrile (TESPN).Diffusion controlled kinetic model with a surface phase concept is developed. The concentration of the pesticides used in this work in the range of 1–20 mg/L. The model is fitted to the real-time adsorption data of phorate, and malathion over various substrates obtained using QCM-D. The results show that TMSPMA functionalized surface being more hydrophilic among all surfaces adsorbs hydrophobic pesticides molecules more uniformly. The monolayer adsorbed mass of pesticides obtained experimentally aligns with the theoretically calculated mass for TMSPMA functionalized silica surface. The adsorption is explained through molecular interactions. A reasonably strong binding with a possibility of reversible binding of phorate and malathion on TMSPMA functionalized surface is observed.

The effect of acrylic silane crosslinker on room‐temperature cured acrylate binder for road markings

AbstractAn acrylic binder with excellent physical properties is prepared using copolymer of methyl methacrylate (MMA) and butyl acrylate monomer (BAM), 2‐hydroxyethyl methacrylate (2‐HEMA), 3‐(trimethoxysilyl)propyl methacrylate (TMSPMA), and additives. The obtained acrylic resins are subjected to a redox initiator system (ROIS) for room temperature curing. The effects of the TMSPMA concentration and [acryl‐copolymer]/[2‐HEMA] ratio on backbone content are studied in terms of traffic marking paint. The mechanical and morphological properties are thoroughly evaluated using universal testing machine (UTM), UV spectrum, and SEM. With increasing TMSPMA content, the adhesive strength and transmittance of the cured resins increase up to a limiting value of TMSPMA content because of the optimizing crosslink network in backbone structure. The introduction of TMSPMA may be effectively attributed to strong adhesive and high transparency of an acrylic resin series. Consequently, acrylic resins with optimal TMSPMA content can be mostly utilized as a high‐performance binder in the traffic marking paint field.