ESR study of poly β-alanine and its derivatives

Abstract

Gamma radiation-induced radicals in poly β-alanine , poly α-methyl-β-alanine and poly β-methyl-β-alanine have been investigated by Electron Spin Resonance Spectrometry technique. ESR spectra of polymers irradiated in nitrogen and air have been simulated by curve fitting software Winsim2002 . The type of radicals generated, their relative abundances, conversion into other radicalic species and their room temperature stability were evaluated. At least two types of radicals have been detected for each polymer. Most stable radicals have been obtained in the case of poly α-methyl-β-alanine .

Keywords

• ESR spectroscopy,radiolysis,curve fitting,dosimetry

Poli b-alanin ve türevlerinin ESR çalışması

Abstract

P oli b-alanin , poli a-metil-b-alanin ve poli b-metil-b-alanin ’in gama ışıması muamelesi ile oluşan radikalleri Elektron Spin Rezonans tekniği ile incelendi. Azot ve hava ortamlarında ışınlanan polimerlerin ESR spektrumları eğri simülasyon yazılımı Winsim2002 kullanılarak simülasyonuları yapıldı. Oluşan radikal türleri, bağıl miktarları, diğer radikalik türlere dönüşümleri ve oda sıcaklığındaki kararlılıkları incelendi. Her polimer için en az iki tür radikal belirlendi. En kararlı radikallerin poli a-metil-b-alanin ’den elde edildiği tesbit edildi

Keywords

• ESR spektroskopisi,radyoliz,eğri uydurma,dozimetri

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