Investigations on the permeability of acrylic powder structures

Ağırtopçu, Yasin
There are many examples where creation and usage of porous substrates play important roles in various fields of application in material science and technology. In the manufacture of ceramic products, as an alternative to the plaster molds, porous resin molds are used İn order to resolve the drawbacks that result from plaster mold cementation. A porous substrate can be produced by various ways. In this study, porous polymeric matrices of pofy(methyl methacrylate) (PMMA) and poh/(methyl methacrylate-co-2-hydroxyethyl methacrylate) [poly(MMA-HEMA)j polymers were prepared by connecting the polymer microspheres to each other by an epoxy adhesive. To improve the surface properties, methyl methacrylate (MMA) was copolymerized with 2-hydroxyethyl methacrylate (HEMA). The microspheres used were synthesized by suspension polymerization and characterization was indone by Nuclear Magnetic Resonance (NMR), Particle Size Analyzer and Scanning Electron Microscope (SEM). The porous samples were prepared with PMMA and poly(MMA-HEMA) copolymer microspheres with two different HEMA contents and their surface energies were measured. In addition, the effect of mean particle diameter of the microspheres used and the epoxy content of the solution used to bind the microspheres, on the impregnation capacity, morphology and the impact strength of the porous samples prepared, were studied. Inclusion of HEMA into the formulation improved the impregnation capacity of the samples. Using microspheres with narrower particle size distribution resulted in larger representative capillary radii and higher rate of impregnation of the samples. Increasing the epoxy content of the solution used to bind the beads, increased the impact strengths of the samples prepared.


Modeling of Spherulite Microstructures in Semicrystalline Polymers
Oktay, Hasan Emre; Gürses, Ercan (2014-09-04)
Polymers constitute an important class of materials with a wide range of application areas in modern life. Among these, semicrystalline polymers (SCP), such as high-density polyethylene (HDPE), Nylon-6, poly(ethylene terephthalate) (PET), isotactic polypropylene (iPP) and ultra high molecular weight polyethylene (UHMWPE), form a sub-set with a significant technological interest. Owing to remarkable deformability and toughness, good impact strength, very low gas-permeability, superior wear resistance and bio...
Synthesis of acrylic based high internal phase emulsion polymers and their application in chromatography
Tunç, Yeliz; Hasırcı, Nesrin; Department of Polymer Science and Technology (2009)
High internal phase emulsion polymers (PolyHIPEs) are new generation materials with their high porosity and interconnected open-cell structures and finds applications in areas such as supports for catalytic systems, separation media and tissue engineering scaffolds. Styrene based PolyHIPEs are currently the most popular choice, but solvent compatibility and poor mechanical properties of these materials prevent their applications. Therefore development of new polyHIPEs with desired mechanical and cellular pr...
Investigations on the biodegradable polymeric and inorganic substrates for controlled drug delivery and bone and cartilage repair
Günay, Aycan; Bayramlı, Erdal; Department of Polymer Science and Technology (2008)
Tissue engineering is an interdisciplinary field that seeks to address the needs by applying the principles of chemistry, biology and engineering for the development of viable substitutes that restore and maintain the function of human bone and cartilage tissues. In tissue engineering, scaffolds play an important role as temporary supports for the transplantation of specific cells and tissues. In this study, poly(ester-urethane)urea (PEUU) and poly(caprolactone) (PCL) scaffolds were fabricated. Scaffolds we...
Revisiting the Challenges in Fabricating Uniform Coatings with Polyfunctional Molecules on High Surface Energy Materials
Oyola-Reynoso, Stephanie; Wang, Zhengjia; Chen, Jiahao; Çınar, Simge; Chang, Boyce; Thuo, Martin (2015-12-01)
Modifying the chemistry of a surface has been widely used to influence interfacial properties of a material or nature of interaction between two materials. This article provides an overview on the role of polyfunctional molecules, specifically silanes, in surface modification of polar surfaces (bearing soft nucleophiles). An emphasis on the mechanism of the reaction in the presence of adsorbed water, where the modifying reagents are hydrolysable, is discussed. To highlight the complexity of the reaction, mo...
A benzimidazole-based conducting polymer and a PMMA-clay nanocomposite containing biosensor platform for glucose sensing
EMRE, FATMA BİLGE; Kesik, Melis; Kanik, Fulya Ekiz; Akpinar, Hava Zekiye; Aslan-Gurel, Evren; Rossi, Rene M.; Toppare, Levent Kamil (2015-09-01)
Development of materials composed of polymer-clay nanocomposites (PCN) and conducting polymers attracts great interest and preferred in various applications. Hereby, polymethylmethacrylate (PMMA) layered silicate nanocomposites were prepared by in-situ suspension polymerization by grafting PMMA with laponite using a suitable grafting agent. The properties of the as-synthesized PCN materials are characterized by differential scanning calorimetry (DSC), thermal gravimetry analysis (TGA) and gel permeation chr...
Citation Formats
Y. Ağırtopçu, “Investigations on the permeability of acrylic powder structures,” M.S. - Master of Science, Middle East Technical University, 2003.