Yazar "Tulumcu, Zeynep" seçeneğine göre listele

Listeleniyor 1 - 3 / 3
  • Küçük Resim Yok
    Öğe
    An orthogonal approach for the synthesis of graft copolymers: Visible light induced free radical polymerization and iniferter processes
    (Taylor & Francis Inc, 2024) Tulumcu, Zeynep; Akyel, Cansu; Ciftci, Mustafa
    Graft copolymers with polystyrene main and poly(ethylene glycol) methyl ether acrylate side chains are synthesized via an orthogonal approach combining visible light induced free radical polymerization and iniferter processes. The method relies on a deliberately designed, double functional monomer, 2,2,2-(triphenylethyl)styrene (TPES), containing both polymerizable and iniferter units.
  • Küçük Resim Yok
    Öğe
    Enhanced Mechanical Performance of Cement Paste Through Incorporation of a Tailored Terpolymer
    (Wiley, 2025) Tulumcu, Zeynep; Ozturk, Murat; Ciftci, Mustafa
    This study presents a novel approach to enhance the mechanical performance of cement pastes through the incorporation of a tailor-made terpolymer synthesized from methyl methacrylate (MMA), hydroxyethyl acrylate (HEA), and tert-butyl acrylate (tBA), which hydrolyzes into PMMA-co-PHEA-co-PAA. Unlike conventional single-polymer systems, this multifunctional terpolymer provides synergistic reinforcement by integrating hydrophobic, hydroxyl, and carboxyl functionalities. The polymer was added at 0%-0.750% by cement weight. Mechanical testing and multi-scale analyses (FT-IR, XRD, SEM, 1H-NMR) revealed a remarkable 94% increase in flexural strength at 0.750% polymer, attributed to interpenetrating polymer networks bridging micro-defects and distributing stress uniformly. Compressive strength peaked at 0.125% due to microstructural densification but declined at higher dosages because of polymer-induced porosity. These findings demonstrate a tunable balance between strength and toughness, positioning PMMA-co-PHEA-co-PAA as a next-generation polymer additive for crack-resistant, flexible cementitious materials.
  • Küçük Resim Yok
    Öğe
    Metal-Free, Sustainable Synthesis of Polycaprolactone-Based Graft Copolymers Through Tandem ROP and ATRP at Ambient Temperature
    (Wiley, 2026) Tulumcu, Zeynep; Zor, Ozge; Ciftci, Mustafa
    A metal-free and sustainable strategy for the synthesis of graft copolymers was developed by combining ring-opening polymerization (ROP) of epsilon-caprolactone with atom transfer radical polymerization (ATRP) at ambient temperature. Polycaprolactone (PCL) backbones bearing initiating sites were first prepared and subsequently employed for ATRP of two different vinyl monomers, methyl methacrylate (MMA) and poly(ethylene glycol) methyl ether acrylate (PEGA). This tandem polymerization approach enabled the controlled preparation of well-defined PCL-g-PMMA and PCL-g-PPEGA graft copolymers without the use of transition-metal catalysts. The successful incorporation of side chains was confirmed by 1H-NMR and FT-IR spectroscopy, while molecular weight distributions were evaluated by gel permeation chromatography (GPC). Differential scanning calorimetry (DSC) revealed the influence of grafting on the thermal properties of the copolymers, and water contact angle (WCA) measurements demonstrated surface wettability changes associated with PEGA incorporation.