Ruhan ALTUN ANAYURT, Cemil ALKAN, Sennur ALAY AKSOY, Sena DEMİRBAĞ, Müyesser Selda TÖZÜM

T POLİMETİLMETAKRİLAT/N-ALKANMİKROKAPSÜLLERİN TERMAL ÖZELLİKLERİNE HİDROFİLİK KOMONOMERİN ETKİSİ

Mikrokapsüllenmiş faz değiştiren material (MEPCMs) olarak, poli(metil metakrilat-ko-2 hidroksi etil akrilat)/n-oktadekan (P(MMA-co-2HEA)/C18) ve poli(metil metakrilat-ko-2 hidroksi etil akrilat)/n-eykosan mikrokapsüller emülsiyon polimerizasyonu metodu ile üretilmiştir. Hidrofilik monomer ilave edilmiş mikrokapsüllerin yapıları, FT-IR spektroskopisi ile aydınlatılmış ve termal özellikleri diferansiyel taramalı kalorimetre (DSC) ve termogravimetrik analiz (TGA) teknikleri ile araştırılmıştır. Mikrokapsüllenmiş faz değiştiren maddelerin yüzey morfolojileri ve parçacık boyutu polarize ışık mikroskobu (POM) ve parçacık analiz edici system (PSA) ile incelenmiştir. DSC tekniği mikrokapsüllerin en fazla 125 J/g enerji depoladığını gösterirken TGA tekniği kararlılıklarını göstermiştir. Parçacık boyutu ve dağılımı analizi mikrokapsüllerin düzenli ve dar aralıklı dağılıma sahip olduğunu göstermiştir. FT-IR spektroskopisi paraffin çekirdeğin etrafında poli(MMA-ko-2-HEA) duvarın başarılı bir şekilde sentezlendiğini göstermiştir. Bunun yanında mikrokapsüllerin termo-fiziksel özelliklerinin mikrokapsül içeriğine şiddetli derecede bağlı olduğu bulunmuştur.

Anahtar Kelimeler:

Polimer sentezi, faz değiştiren maddeler (FDMler), mikrokapsüllenmiş FDMler, PMMA, kopolimer

INFLUENCE OF HYDROPHILIC COMONOMER ON THERMAL PROPERTIES OF POLYMETHYLEMETHACRYLATE/ N-ALKANES MICROCAPSULES

A series of poly(MMA-co-2-HEA)/n-octadecane (P(MMA-co-2HEA)/C18) and poly(MMA-co-2-HEA)/n-eicosane (P(MMA-co-2HEA)/C20) microcapsules were prepared by an emulsion polymerization method as microencapsulated phase change materials (MEPCMs). The structural identification was done by using FTIR spectroscopy and thermal properties of the hydrophilic monomer imcorporated microcapsules were investigated using Differential Scanning Calorimetry (DSC) and Thermogravimetric analysis (TGA) techniques. The surface morphology and particle size of MEPCMs were studied using a Polarised Optical Microscope (POM) and a Particle Size Analysizer (PSA) respectively. DSC indicated that the microcapsules containing highest amount of the n-alkane had a latent heat of 125 J/g as and TGA technique showed about thermal stability. The particle size and distribution analysis showed that the microcapsules had uniform and narrow size distrubiton. Also it was confirmed by FTIR spectroscopy that the poly(MMA-co-2-HEA) shell was successfully synthesized as the shell of the paraffin core. Besides it was found that the thermo-physical properties were

Keywords:

Polymer synthesis, phase change materials (PCMs), microencapsulated PCMs, PMMA, copolymer,

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