Bekir SARI, Muzaffer TALU, H. Beytiye ÖZGÜN

Synthesis of new polymers: Copolymerization of 4-hydroxybenzoic acid and 4-(Hydroxymethyl) benzoic acid

4-Hidroksibenzoik asit ve 4-(hidroksimetil)benzoik asit monomerlerinden çıkılarak, kütle polimerleşmesi yöntemi ile 320°C'ye ulaşan yüksek yüksek sıcaklıklarda bir seri kopolimer sentezlendi. Sentezlenen kopolimerlerin yapıları $^1H$-NMR ve $^{13}C$-NMR spektroskopisi, viskozite, termogravimetrik analiz ve optik mikroskopi yöntemi ile aydınlatıldı.Polimerlerin molekül ağırlıkları sıvı kromatografısi-kütle spektroskopisi yöntemi ile belirlendi. Polimerlerin sıvı kristal özellikleri polarize mikroskop ile 350°C'ye kadar ısıtılarak incelendi. Termogravimetrik ölçümlerden polimerlerin termal bozunma sıcaklıklarının 399°C ile 433°C arasında olduğu belirlendi.

4-Hidroksibenzoik asit ve 4-hidroksimetilbenzoik asit kopolimerinin sentezi

A series of copolyesters of 4-hydroxybenzoic acid and 4-(hydroxymethyl)benzoic acid was prepared by the poly condensation process in bulk at temperatures up to 320°C. The copolyesters were characterized by$^1H$-NMR and $^{13}C$-NMR spectra, solution viscosity, thermogravimetric analysis arid optical microscopy. Molecular weights were determined by Liquid Chromatography-Mass Spectroscopy. Birefringence was observable under the polarizing microscope up to temperatures of 350°C. Thermogravimetric analysis measurements indicated that onset of the thermal degradation of samples were between 399°C and 433°C.

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