Effects of boron compound on characteristics of poly(methyl methacrylate) and its nanocomposites

Göktaş, Müberra
In this work, composites of poly(methyl methacrylate) and benzene-1,4diboronic acid (BDBA) and their nanocomposites with organically modified montmorillonite OMMT prepared by solution and melt mixing, were characterized to study effects of boron content and the preparation method on the properties of PMMA. SEM images showed homogeneous dispersion of BDBA particles for the melt blended, whereas, agglomeration for the solution mixed PMMA/BDBA composites. XRD and TEM results of PMMA nanocomposites indicated that its nanocomposites prepared by both techniques were generally consisted of intercalated/exfoliated OMMT layers. Thermogravimetric analysis (TGA) and direct pyrolysis mass spectrometry (DPMS) indicated an increase in the thermal stability of the composites upon incorporation of boron and Cloisite 30B into PMMA matrix prepared by both techniques. This behavior was associated with generation of units by transesterification reactions between BDBA and PMMA. In addition, at high BDBA loadings, formation of a boron network structure was recorded for the composites prepared by solution casting technique. During the degradation of the PMMA nanocomposites with OMMT, the interactions between BDBA and ester groups of PMMA became more dominant than those among BDBA particles generating a boron network structure. Limiting oxygen index (LOI) and UL-94 vertical tests revealed no significant improvement in flammability characteristics for the composites. In addition, noticeable decrease in % elongation at break and tensile strength of PMMA was observed although stiffness of the polymer was slightly improved upon addition of BDBA and organoclay.


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Yilmaz, Nil Ezgi Dincer; Karakaş, Gürkan (2020-01-01)
B/Fe2O3 samples were prepared by mixing nano sized boron powder with iron oxide xerogels that had been synthesized using a sol-gel method that included various types of proton scavengers such as 1,2-epoxybutane, tetrahydrofuran, 1,4-dioxane and ammonium hydroxide. The effects of the proton scavengers and drying conditions on the textural properties of the iron oxide samples and on the heat output and thermal behavior of the nano-composites were examined. The iron oxide samples were subjected to direct dryin...
Effects of pH, Initiator, Scavenger, and Surfactant on the Ozonation Mechanism of an Azo Dye (Acid Red-151) in a Batch Reactor
Oezbelge, Tuelay A.; Erol, Funda (Informa UK Limited, 2009-01-01)
In this study, an initiator (Fe2+) and a scavenger (CO32(-)) were used at different concentrations in a batch reactor to investigate the reaction mechanism of ozonation of a model azo dye, namely Acid Red-151 (AR-151). Also, the effect of a nonionic surfactant known as a major pollutant in many industrial wastewaters, namely polyethylene glycol (PEG), was observed on the degradation rate of AR-151. The experimental parameters and their ranges were: pH (2.5-10), initiator (0.8-50mg/L of Fe2+), surfactant (10...
Effects of aromatic diboronic acid on thermal charateristics of polybenzoxazines based on phenol and aniline
Telli, Aysegul Hisar; Hacaloğlu, Jale (2018-11-01)
In this work, polybenzoxazines based on phenol and aniline were prepared by curing as-synthesized and purified monomers in the presence of aromatic diboronic acid, BDBA. Condensation reactions between BOH groups of diboronic acid and phenolic OH groups of benzoxazine took place during curing only when unreacted phenol, or low mass oligomers were present in the medium. Generation of fragments involving B-O-C groups and significant improvement in thermal characteristics were detected upon curing the as-synthe...
Effects of synthesis, doping methods and metal content on thermoluminescence glow curves of lithium tetraborate
Kayhan, Mehmet; Yılmaz, Ayşen (Elsevier BV, 2011-07-28)
Lithium tetraborate: Li(2)B(4)O(7), (LTB) has been synthesized and doped with various Mn content by different methods, such as, high temperature solid state synthesis and solution assisted synthesis methods. Powder XRD results proved the formation of solid-solution by replacing Mn with Li ions in LTB lattice at lower amount of Mn doping, for example 0.1-3.0% Mn doping. In this research TL glow curves of Mn doped lithium tetraborate (LTB: Mn) produced by using different synthesis and doping methods and the e...
Citation Formats
M. Göktaş, “Effects of boron compound on characteristics of poly(methyl methacrylate) and its nanocomposites,” M.S. - Master of Science, Middle East Technical University, 2016.