Epoxidized rosin acids as co-precursors for epoxy resins

A series of novel epoxy resins were prepared from chemically modified rosin, mainly constituted of abietic acid, diglycidyl ether of bisphenol-A (DGEBA) in different percentages as co-reactants, and isophorone diamine as cross-linking agent. Reactive epoxide groups were introduced in the structure of this common pine tree derivative. The chemical structures of various epoxidized rosin acids precursors were confirmed by NMR spectroscopy. Differential scanning calorimetry and dynamic mechanical analysis were used to determine the glass transition temperature and the elastic modulus of the cured epoxy resins. Relatively rigid materials with thermo-mechanical properties depending on the structure of rosin acid derivatives and their ratios with DGEBA were obtained. Epoxy precursors based on renewable rosin can be efficiently used as co-additives of DGEBA for epoxy products

Autoxidized Oleic Acid Bifunctional Macro Peroxide Initiators for Free Radical and Condensation Polymerization. Synthesis and Characterization of Multiblock Copolymers

Secilmis Canbay, Hale/0000-0002-3783-8064; Hazer, Baki/0000-0001-8770-805XWOS: 000491549500023TARAMASCOPUSIndex: SCI-E, WOS, ScopusTARAMAWOSAutoxidation of unsaturated fatty acids gives fatty acid macroperoxide initiators containing two functionalities which can lead to free radical and condensation polymerizations in a single pot. The oleic acid macroperoxide initiator obtained by ecofriendly autoxidation (Pole4m) was used in both the free radical polymerization of styrene and the condensation polymerization with amine-terminated polyethylene glycol (PEGNH2) to obtain triblock branched graft copolymers. The narrow molar masses of the poly oleic acid-g-styrene (PoleS) and poly oleic acid-g-styrene-g-PEG (PoSG) graft copolymers were successfully obtained. The inclusion of oleic acid decreased the glass transition temperature of the polystyrene segment because of the plasticizing effect of oleic acid. In addition, a mechanical property of the copolymer was improved when compared with the pure PS. Structural characterization, morphology of the fracture surface, micelle formation, thermal analysis and molar masses of the obtained products were also evaluated.Kapadokya University Research Fund [KUN.2018-BAGP-001]; Bulent Ecevit University Research FundBulent Ecevit University [BEU-2017-72118496-01]This work was supported by the Kapadokya University Research Fund (KUN.2018-BAGP-001) and Bulent Ecevit University Research Fund (#BEU-2017-72118496-01). The Authors thank to Koray Alper and Fatih Pekdemir for taking SEM and FTIR spectra, respectively. The Authors thank to Serdar Coban, Sidika Sarac Tabakli and Gulsen Darici (Cilas Kaucuk, Devrek, Zonguldak, Turkey) for taking stress-strain measurements

Synthesis and characterization of amphiphilic triblock copolymers including -alanine/-methyl--alanine and ethylene glycol by "click" chemistry

WOS: 000460703600029Terminally azide poly--alanine (PBA-Az) was directly obtained by hydrogen transfer polymerization of acrylamide in the presence of sodium azide as an initiator. However, terminally azide poly(-methyl -alanine) (PmBA-Az) was synthesized by the reaction between terminally bromo poly(-methyl -alanine) and sodium azide. Dipropargyllated polyethylene glycol (PEG-di-Pr) was synthesized by using the reaction of PEGs with different molecular weights and propargyl bromide. Synthesis of poly(-alanine-b-ethylene glycol-b--alanine) and poly(-methyl -alanine-b-ethylene glycol-b--methyl -alanine) amphiphilic ABA triblock copolymers was achieved via click chemistry of PBA-Az or PmBA-Az and PEG-di-Pr with different molecular weight. Click reaction parameters such as concentration and time were assessed. Macromonomers and the amphiphilic triblock copolymers were characterized by using H-1-NMR, FT-IR, MALDI-MS, TGA, and elemental analysis techniques. The multi-instruments studies of the obtained amphiphilic triblock copolymers reveal that the copolymers easily formed as a result of click chemistry