Thermal analysis of electroinitiated and radiation induced poly(epoxycyclopentanes) and poly(epoxycyclohexanes) by mass spectrometry

Thermal behaviour of electroinitiated and radiation induced poly(epoxycyclopentanes), PECP, and poly(epoxycyclohexanes), PECH, have been studied by a direct pyrolysis mass spectrometry technique. The mechanism of thermal degradation of the samples prepared by electroinitiation was found to be a radical depolymerization mechanism yielding mainly monomer. The broader temperature ranges of thermal decomposition in the case of polymer samples prepared by irradiation may be attributed to more complicated degradation mechanisms such as random bond cleavages for PECP and dehydrogenation reactions stabilizing high mass fragments before decomposition of the main chain for PECH.
European Polymer Journal


Investigation of cell migration and proliferation in agarose based hydrogels for tissue engineering applications
Vardar, Elif; Hasırcı, Nesrin; Hasırcı, Vasıf Nejat; Department of Biomedical Engineering (2010)
Hydrogels are three dimensional, insoluble, porous and crosslinked polymer networks. Due to their high water content, they have great resemblance to natural tissues, and therefore, demonstrate high biocompatibility. The porous structure provides an aqueous environment for the cells and also allows influx of nutrients needed for cellular viability. In this study, a natural biodegradable material, agarose (Aga), was used and semi-interpenetrating networks (semi-IPN) were prepared with polymers having differen...
Ageing characteristics of copper based shape memory alloys
Tarhan, Elif; Bor, Şakir; Department of Metallurgical and Materials Engineering (2004)
Martensite-to-Beta transformation temperatures of CuAlNiMn and CuAlNi shape memory alloys has been determined by differential scanning calorimetry (DSC). In CuAlNiMn alloys, each new betatizing treatment has resulted in randomly varying transformation temperatures on the same specimen and an anomalously diffuse and serrated Martensite-to-Beta transformation peaks in the first cycle. Therefore, as quenched alloy samples were thermally cycled for three times in DSC prior to ageing to obtain thermally stable a...
Nanohardness measurements of heavy ion irradiated coarse- and nanocrystalline-grained tungsten at room and high temperature
El-Atwani, O.; Weaver, J. S.; Esquivel, E.; Efe, Mert; Chancey, M. R.; Wang, Y. Q.; Maloy, S. A.; Mara, N. (Elsevier BV, 2018-10-01)
Heavy ion irradiation was performed on coarse and nanocrystalline-grained tungsten (CGW and NGW, respectively) at room temperature (RT) and 1050 K from 0.25 to 4 dpa to simulate radiation damage for fusion energy applications. TEM and nanohardness measurements of irradiated samples were made to quantify the radiation tolerance of these two candidate materials. In this case, TEM is used to quantify the defect morphology at low dpa values and determine the barrier strength coefficients of the different defect...
Quantum statistical effects on fusion dynamics of heavy ions
Ayik, S; Yilmaz, B; Gokalp, A; Yılmaz, Osman; Takigawa, N (American Physical Society (APS), 2005-05-01)
To describe the fusion of two very heavy nuclei at near barrier energies, a generalized Langevin approach is proposed. The approach incorporates the quantum statistical fluctuations in accordance with the fluctuation and dissipation theorem. It is illustrated that the quantum statistical effects introduce an enhancement of the formation of a compound nucleus, though the quantum enhancement is somewhat less pronounced as indicated in the previous calculations.
Molecular-dynamics simulation of radiation damage on copper clusters
Erkoç, Şakir (2000-07-01)
The effect of radiation damage on copper clusters has been investigated by performing molecular-dynamics simulation using empirical potential energy function for interaction between copper atoms. The external radiation is modeled by giving extra kinetic energy in the range of 5- 50 eV to initially chosen atom in the cluster. It has been found that the atom having extra kinetic energy dissociates independently from the amount of given energy in the studied range.
Citation Formats
J. Hacaloğlu and A. M. Önal, “Thermal analysis of electroinitiated and radiation induced poly(epoxycyclopentanes) and poly(epoxycyclohexanes) by mass spectrometry,” European Polymer Journal, pp. 103–107, 1995, Accessed: 00, 2020. [Online]. Available: