Kondense Tanenin Fenol ile Asidik Ortamda Çözülmesi ve Formaldehit ile Reaksiyon Parametrelerinin Araştırılması

Öz

Bu çalışmanın amacı, akasya (Acacia mollissima L.) kabuğundan elde edilen kondanse tanenin fenol ve formaldehit ile asidik ortamda reçineleşme özelliklerinin belirlenmesidir. Bu amaçla, kondense tanen ile fenolün geri soğutucu altında farklı sülfürik asit konsantrasyonu (%1-5), değişik sıcaklık (100-160 °C) ve süreler (30-120 dakika) uygulanarak reaksiyon şartlar çalışılmıştır. Daha sonra 10-50 dakika arasında değişen farklı reçineleştirme sürelerinde fenolatlı kondanse tanen formaldehit ile reaksiyon oluşturması sağlanarak yeni kopolimerler elde edilmiştir. Yeni polimerlerin termal davranışları incelenmiştir. Elde edilen sonuçlara göre fenolün kondanse tanen ile reaksiyonu için asit konsantrasyonu, reaksiyon sıcaklığı ve reaksiyon süresinin çok kritik olduğu bulunmuştur. Kombine fenol miktarı asit konsantrasyonundan büyük ölçüde etkilenmiştir. %5’lik sülfürik asit konsantrasyonunda verim yüzdesi olarak %40'ın üzerinde polimer elde edilmiştir.

Anahtar Kelimeler

• Tanen
• kondense tanen
• fenol

Dissolution of Condensed Tannin with Phenol in Acidic Medium and Investigation of reaction Parameters with Formaldehyde

Öz

The objective of this study was to determine the resinification properties of phenolated condensed tannin obtained from acacia (Acacia mollissima L.) bark with formaldehyde in an acidic medium. For this purpose, condensed tannin was reacted with phenol under reflux using different sulfuric acid concentration (1-5%), temperature (100-160 °C) and time (30-120 min). Then, new copolymers were obtained by reacting the phenolated condensed tannin with formaldehyde at different resinification times varying in the range of 10-50 min. The thermal behavior of obtained polymers were investigated. According to the results, acid concentration, reaction temperature and reaction time were found to be very critical for the reaction of phenol with condensed tannin. The amount of combined phenol was greatly affected by the acid concentration. At 5% sulfuric acid concentration, more than 40% polymer was obtained as a percent polymer.

Anahtar Kelimeler

• Tannin
• condensed tannin
• phenol
• formaldehyde

Kaynakça

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