Propyl Methacrylate Silane Research Articles

Improvement of PLA-PVA/chitosan nanocomposite laminate film for packaging via crosslinking with electron beam irradiation: Mechanical, thermal and antimicrobial analysis

This research investigated and developed a laminate packaging film of poly(lactic acid) (PLA) and poly(vinyl alcohol) (PVA) containing modified chitosan nanoparticles (MCSNPs) treated with 3-(trimethoxysilyl)propyl methacrylate silane (TMSPM) which functioned both as a reinforcement and as an antimicrobial filler. Electron beam irradiation caused crosslink between the PVA and MCSNP molecules via the free radical of carbonyl in the methacrylate group of TMSPM-grafted chitosan nanoparticles and the free radical of hydroxyl group in poly(vinyl alcohol). This improved the PVA hydrophobicity. In addition, the laminate with PVA-g-MCSNPs film irradiated with a 30 kGy electron beam showed the best performance properties due to improved interfacial adhesion between PLA and PVA-g-MCSNPs. As a consequence, the mechanical and thermal properties improved. The 30 kGy irradiated film also had better antibacterial activity against both Escherichia coli and Staphylococcus aureus.

Mechanical properties and weather stability of a novel nanocomposite coating based on fluoroethylene/vinyl ether copolymer and organically modified zirconium dioxide nanoparticles

AbstractThis study aims to investigate the effect of organically modified zirconium dioxide nanoparticles (m‐ZrO2 NPs) on the mechanical properties, morphology, and weather stability of fluoroethylene/vinyl ether copolymer (FEVE). To modify the surface of ZrO2 NPs, a 3‐(trimethoxysilyl)propyl methacrylate silane (TMSPM) organic coupling agent was utilized. The ZrO2 NPs were treated with 3 wt.% of TMSPM using a solution method with ultrasonication assistance at 50°C. Various amounts of m‐ZrO2 NPs (1, 2, and 4 wt.% of FEVE weight) were dispersed in a xylene solvent and mixed with FEVE resin. The mixture was then cured with polyisocyanate. The mechanical properties of the FEVE nanocomposite coatings, including impact resistance, adhesion, and abrasion resistance were measured. The morphology of the coatings was analyzed using scanning electron microscopy (SEM). To evaluate the weather stability of the coatings, an accelerated weathering test was conducted in a QUV/SPRAY chamber. This test could potentially affect the chemical structure, weight/thickness, and surface characteristics of the coatings. The carbonyl index, weight loss, and changes in mechanical properties of the coatings were monitored and discussed at different intervals during the accelerated weathering test. In addition, the morphology of the coatings after undergoing 42 cycles of accelerated weathering testing was analyzed. The results indicated that m‐ZrO2 NPs had a positive impact on the weather durability of FEVE resin, particularly in significantly enhancing the weather resistance of the FEVE‐based coatings. Therefore, these coatings exhibit potential for outdoor applications.Highlights Silane modified ZrO2 nanoparticles improve the mechanical properties of FEVE resin. The weather stability of FEVE resin increases as using modified ZrO2 nanoparticles. The suitable content of modified ZrO2 nanoparticles for FEVE resin is 2 wt.%. Mechanical properties of the nanocomposite reduce slightly after 42 cycle testing. Propose the mechanism for weather resistance of the nanocomposite coating.

Characteristics, properties and morphology of calcium silicate nanoparticles modified with some silane coupling agents

This paper presents the characteristics, properties and morphology of calcium silicate (CS) nanoparticles modified with silane coupling agents, namely vinyltrimetoxy silane (VTMS) and 3-(trimethoxysilyl)propyl methacrylate silane (MPTS), by the hydrolysis method. Effect of content of silane coupling agents on CS nanoparticles modified was investigated. The obtained results suggested that silane coupling agents were successfully grafted onto the surface of CS nanoparticles. The performance and amount of silane coupling agent grafting on CS nanoparticles depended on the nature and initial content of silane coupling agent. The highest grafting yield on CS nanoparticles performances was 32.8 % for VTMS at initial content of 5 wt. % and 48.80% for MPTS at initial content of 10 wt. %. Organo-modification decreased thermo-oxidation stability of modified CS nanoparticles because of the decomposition of organic moiety in silane coupling agent while hydrophobicity of modified CS surface increased. Thus, agglomeration of modified CS nanoparticles reduced significantly. The unmodified CS nanoparticles had size distribution (in distilled water) peak at nearly 500 nm while the size distribution (in distilled water) peak of CS modified 10 wt.% MPTS was approximately 150nm.

Assessment of some characteristics, properties of a novel waterborne acrylic coating incorporated TiO2 nanoparticles modified with silane coupling agent and Ag/Zn zeolite

Effect of rutile TiO2 nanoparticles modified with 3-(trimethoxysilyl) propyl methacrylate silane - TMSPM (m-TiO2) and Ag/Zn zeolite on the properties, and durability of acrylic waterborne coatings was studied. The obtained results indicated that m-TiO2 nanoparticles and Ag/Zn zeolite could disperse regularly in the acrylic polymer matrix. Consequently, the acrylic coating's abrasion resistance was improved in the presence of m-TiO2 or/and Ag/Zn zeolite. The acrylic coating's abrasion resistance depended on the content of m-TiO2 nanoparticles as well as the initial TMSPM content for modification of rutile TiO2 nanoparticles. The abrasion resistance of the m-TiO2 nanocomposite coating was higher than that of the unmodified TiO2 nanocomposite coating. The acrylic coating filled by 2 wt% TiO2 modified with 3 wt% TMSPM had the highest abrasion resistance value, leveling off at 187.2 L/mil. The abrasion resistance of acrylic coating filled by m-TiO2 reduced with increasing too high m-TiO2 nanoparticles content and using initial TMSPM content in high level for TiO2 modification. The starting temperature of weight loss of acrylic coating filled by m-TiO2 was lower than that of the neat acrylic coating. In comparison with the m-TiO2 nanoparticles, the Ag/Zn zeolite particles showed a lower improvement for acrylic coating properties, i.e. abrasion resistance, weathering durability, but the Ag/Zn zeolite particles expressed an excellent antibacterial activity. Hence, combination of the m-TiO2 nanoparticles and Ag/Zn zeolite particles could enhance the acrylic waterborne coatings' properties. The acrylic coating filled by 2 wt% m-TiO2 nanoparticles and 1 wt% Ag/Zn zeolite particles illustrated high abrasion resistance, good weather durability, and superior antibacterial activity for both of E. coli and S. aureus. This coating is promising for environmental friendly building materials application.

UV-curable nanocomposite based on methacrylic-siloxane resin and surface-modified TiO2 nanocrystals.

A novel UV-light-curable nanocomposite material formed of a methacrylic-siloxane resin loaded with 1 wt % oleic acid and 3-(trimethoxysilyl)propyl methacrylate silane (OLEA/MEMO)-coated TiO2 nanorods (NRs) has been manufactured as a potential self-curing structural coating material for protection of monuments and artworks, optical elements, and dental components. OLEA-coated TiO2 NRs, presynthesized by a colloidal chemistry route, have been surface-modified by a treatment with the methacrylic-based silane coupling agent MEMO. The resulting OLEA/MEMO-capped TiO2 NRs have been dispersed in MEMO; that is a monomer precursor of the organic formulation, used as a "common solvent" for transferring the NRs in prepolymer components of the formulation. Differential scanning calorimetry and Fourier transform infrared spectroscopy have allowed investigation of the effects of the incorporation of the OLEA/MEMO-capped TiO2 NRs on reactivity and photopolymerization kinetics of the nanocomposite, demonstrating that the embedded NRs significantly increase curing reactivity of the neat organic formulation both in air and inert atmosphere. Such a result has been explained on the basis of the photoactivity of the nanocrystalline TiO2 which behaves as a free-radical donor photocatalyst in the curing reaction, finally turning out more effective than the commonly used commercial photoinitiator. Namely, the NRs have been found to accelerate the cure rate and increase cross-linking density, promoting multiple covalent bonds between the resin prepolymers and the NR ligand molecules, and, moreover, they limit inhibition effect of oxygen on photopolymerization. The NRs distribute uniformly in the photocurable matrix, as assessed by transmission electron microscopy analysis, and increase glass transition temperature and water contact angle of the nanocomposite with respect to the neat resin.

Improvement of impact properties of polypropylene by modification with very low‐density polyethylene

AbstractVery low‐density polyethylene (VLDPE) was compounded with polypropylene (PP) to improve its impact strength. VLDPE was modified by grafting 3‐(trimethoxysilyl) propyl methacrylate silane (MS) to VLDPE to prepare mVLDPE. PP was melt‐mixed either with VLDPE or mVLDPE together with Cloisite®20A (C20A). The composites exhibited a phase‐separated morphology, irrespective of whether the VLDPE had been modified with the silane compounds or not. Incorporation of C20A decreased the domain size of the dispersed phases of both PP/VLDPE and PP/mVLDPE blends. The tensile strength and elongation at break of PP/VLDPE and PP/mVLDPE were improved by the addition of C20A. In contrast, their impact strengths were reduced by the clay. However, the decrease in impact strength was less significant in PP/mVLDPE/C20A than in PP/VLDPE/C20A. The superior mechanical properties of PP/mVLDPE/C20A over PP/VLDPE/C20A were attributed to enhanced interfacial interactions originating from chemical reactions between silane residues on mVLDPE and the silanol groups of C20A. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011

Effect of temperature on the silane coupling agents when bonding core resin to quartz fiber posts

Objectives To evaluate the effect of different silane agents and air-drying temperatures on bond strength of translucent quartz fibre posts to composite resin. Methods The post surface was etched with 10 vol% hydrogen peroxide for 20 min. A two-liquid coupling agent containing 4-methacryolxyethyl trimellitate anhydride (4-META) and γ-trimethoxysilyil propyl methacrylate (γ-MPTS) and two pre-hydrolyzed single component silanes containing 3-methacryloxypropyltrimethoxysilane (3-MPS) and glycid-oxi-propyl-trimetil-oxi-silane (GPS), respectively, were used for treating the fiber posts. Two different post-silanization drying temperatures were applied (21 and 38 °C). A dual-cure composite resin (Core Paste XP) was selected to build-up the core around posts, obtaining cylindrical specimens that were serially cut in beams and subsequently loaded in tension (μTBS) at a cross-head speed of 1 mm/min until failure. Bond strength data were statistically analyzed by two-way ANOVA and Student–Newman–Keuls tests ( α = 0.05). Results Warm air-drying determined significantly higher bond strengths ( p < 0.001) for glycid-oxi-propyl-trimetil-oxi-silane (11.6 MPa) and 4-methacryolxyethyl trimellitate anhydride/γ-trimethoxysilyil propyl methacrylate silane (11.7 MPa). These two systems exhibited lower bond strengths (6.9 and 8.8 MPa, respectively) than 3-methacryloxypropyltrimethoxysilane (11.0 MPa) when dried at 21 °C. No statistical differences were recorded for 3-methacryloxypropyltrimethoxysilane when drying at 21 or 38 °C. Significance The composition of the silane coupling agent in terms of acidic content, solvent rate or degree of hydrolysis may influence resin/post bond strength when dried at 21 °C. Drying at 38 °C most likely facilitates the evaporation of solvents present in the silane agent, resulting in increased bond strength of the composite resin to the fiber post.