İletken Polipirol-poli(akrilonitril-ko-stiren) Esaslı Kompozit Sentezi Ve Karakterizasyonu; Nano Lif Eldesi
İletken Polipirol-poli(akrilonitril-ko-stiren) Esaslı Kompozit Sentezi Ve Karakterizasyonu; Nano Lif Eldesi
Dosyalar
Tarih
2010-07-08
Yazarlar
Balkan, Timuçin
Süreli Yayın başlığı
Süreli Yayın ISSN
Cilt Başlığı
Yayınevi
Fen Bilimleri Enstitüsü
Institute of Science and Technology
Institute of Science and Technology
Özet
Bu çalışma iki bölümden oluşmaktadır. Birinci bölümde, elektromanyetik kalkan ve absorban panel uygulamalarında kullanılmak üzere yeni, polimerik nanokompozit malzemeler sentezlemek amaçlanmıştır. Akrilonitril ve stirenin emulsiyon polimerizasyonu, potasyum persulfat başlatıcısı kullanılarak su ortamında yapılmış ve Polipirol (PPy)/poli(akrilonitril-ko-stiren) (SAN) kompozit ince filmleri, pirolun poli(akrilonitril-ko-stiren) matrisinde kimyasal polimerizasyonu ile hazırlanmıştır. Başlangıçta eklenen pirol konsantrasyonunun elde edilen polimerik film özellikleri üzerindeki etkisi araştırılmıştır. Pirol miktarının, kompozit filmlerin dielektrik geçirgenliği, dielektrik kaybı ve elektriksel özellikleri üzerindeki etkisi 0.01 Hz ile 10 MHz frekans aralığında analiz edilmiştir. Kompozit film içerisindeki pirol miktarının artması ile AC iletkenlik, dielektrik sabitleri ve dielektrik kaybı artmıştır. Çalışmanın ikinci bölümünde, tekstil endüstrisinde yeni nesil ürünlerde elektrostatik deşarj, sensor gibi uygulama alanlarında kullanılmak üzere polipirol/poli(akrilonitril-ko-stiren) bazlı nano liflerin eldesi amaçlanmıştır. Pirolun poli(akrilonitril-ko-stiren) kopolimer matrisinde oksidatif polimerizasyonu gerçekleştirilmiş ve bu çözeltiden elektrospin metodu ile nano lifler elde edilmiştir. FTIR-ATR analizi sonucu polipirol oluşumundan sonra polipirola ait CH pikinin titreşimi elde edilmiştir. Bu gruba ait pikin polipirol oluşumunu bağlı olarak, başlangıçta eklenen pirol miktarı ile lineer bir ilişki olduğu belirlenmiştir. Taramalı elektron mikroskop görüntüleri nano liflerin çaplarının polipirol miktarına bağlı olduğunu ve ortalama nano lif çaplarının başlangıçta eklenen pirol miktarının artması ile azaldığını göstermiştir.
This study can be categorized into two parts. The first part aims to synthesis new polymeric nanocomposite materials which can be used for electromagnetic interference shielding and absorbent panel applications. Emulsion polymerization of acrylonitrile (AN) and styrene (St) initiated by potassium persulfate (KPS) in the aqueous medium was performed and polypyrrole (PPy)/poly(acrylonitrile-co-styrene) (SAN) composite thin films were prepared by chemical polymerization of pyrrole in the presence of the poly(acrylonitrile-co-styrene) matrix. Effect of concentration of initially added pyrrole content on the properties of resulting polymeric film was investigated. The influence of the pyrrole content on the dielectric permittivity, dielectric loss and electrical properties of the composite films were analyzed in the frequency range from 0.01 Hz to 10 MHz. By the increase in the amount of pyrrole in the composite film, AC conductivity, dielectric constants and dielectric loss increased. The second aim was to obtain PPy-SAN based nanofibers for use new generation products such as electrostatic discharge, sensors application in textile industry. The oxidative polymerization of pyrrole (Py) by cerium (IV) on the poly(acrylonitrile-co-styrene) copolymer matrix was performed. Nanofibers were obtained from this solution by electrospinning method. A new absorption band was observed corresponding the CH in plane vibration of polypyrrole by FTIR-ATR analysis. A linear relationship was determined between the absorbance ratios of functional groups corresponding to the conjugated polymeric units and initial Py concentration. Scanning electron microscope images indicated that the diameters of nanofibers were dependent on PPy content and that the average nanofiber diameters were reduced by increasing the initially added Py content.
This study can be categorized into two parts. The first part aims to synthesis new polymeric nanocomposite materials which can be used for electromagnetic interference shielding and absorbent panel applications. Emulsion polymerization of acrylonitrile (AN) and styrene (St) initiated by potassium persulfate (KPS) in the aqueous medium was performed and polypyrrole (PPy)/poly(acrylonitrile-co-styrene) (SAN) composite thin films were prepared by chemical polymerization of pyrrole in the presence of the poly(acrylonitrile-co-styrene) matrix. Effect of concentration of initially added pyrrole content on the properties of resulting polymeric film was investigated. The influence of the pyrrole content on the dielectric permittivity, dielectric loss and electrical properties of the composite films were analyzed in the frequency range from 0.01 Hz to 10 MHz. By the increase in the amount of pyrrole in the composite film, AC conductivity, dielectric constants and dielectric loss increased. The second aim was to obtain PPy-SAN based nanofibers for use new generation products such as electrostatic discharge, sensors application in textile industry. The oxidative polymerization of pyrrole (Py) by cerium (IV) on the poly(acrylonitrile-co-styrene) copolymer matrix was performed. Nanofibers were obtained from this solution by electrospinning method. A new absorption band was observed corresponding the CH in plane vibration of polypyrrole by FTIR-ATR analysis. A linear relationship was determined between the absorbance ratios of functional groups corresponding to the conjugated polymeric units and initial Py concentration. Scanning electron microscope images indicated that the diameters of nanofibers were dependent on PPy content and that the average nanofiber diameters were reduced by increasing the initially added Py content.
Açıklama
Tez (Yüksek Lisans) -- İstanbul Teknik Üniversitesi, Fen Bilimleri Enstitüsü, 2010
Thesis (M.Sc.) -- İstanbul Technical University, Institute of Science and Technology, 2010
Thesis (M.Sc.) -- İstanbul Technical University, Institute of Science and Technology, 2010
Anahtar kelimeler
Polipirol,
Kompozit,
Nano Lif,
Polypyrrole,
Composite,
Nanofiber