Bir Dizi Yeni Aşı Kopolimerin Sentezi, Karakterizasyonu ve Elektroeğirme Yöntemi İle Nano/Mikrofiberlerinin Elde Edilmesi

Abstract

Hidrojen transfer polimerizasyonu (HTP) ile uç grubu olefinik olan oligomerlerin elde edildiği ortaya konulmuştur. Bu oligomerik yapıların kimyasal modifikasyonu ile fonksiyonlandırılması (aktifleştirilmesi), bu yapının makromonomer olarak kullanımı ve yeni blok kopolimerlerin elde edildiği de bilinmektedir. Tez çalışmasında, akrilamit, metakrilamit ve krotonamitten HTP ile elde edilen oligomerik yapılar makromonomer olarak kullanılmıştır. Bu oligomerik yapılar ile tek tek akrilik asit, metakrilik asit ve krotonik asit gibi hidrofilik vinil monomerlerinin serbest radikal polimerizasyonu çözelti ortamında çalışılmıştır. Yani, olefin uçlu makromonomerlerin ve vinil monomerlerinin serbest radikal polimerizasyonunda aynı zincirde bulunacakları öngörülerek vinil monomerinin homopolimerine makromonomerlerin aşılanması hedeflenmiştir. Böylece, karbon iskeletine sahip bir vinil polimerine amit iskeleti olan dalların eklenmesi başarılmıştır. Krotonik asit ve her üç makromonomerin kullanıldığı sentez çalışmalarında polimer sentezi sağlanamamıştır. Ayrıca, poli(β-metil β-alanine) makromonomeri kullanılan sentez denemelerinde de homopolimer (PAA ve PMA) elde edilebilmiştir. Sentezlenmesi planlanan aşı kopolimerlerin bir kısmı başarıyla sentezlenmiştir. Bunlar; poli(akrilik asit-aşı-β-alanin), poli(akrilik asit-aşı-α-metilβ-alanin), poli(metakrilik asit-aşı-β-alanin) ve poli(metakrilik asit-aşı-α-metilβ-alanin) aşı kopolimerleridir. İzolasyonu sağlanan bu kopolimerlerin FT-IR, 1H-NMR, elementel analiz, DSC ve TGA teknikleri ile karakterizasyon sağlanmıştır. Formik asit veya formik asit/metanol çözücüleri kullanılarak %10 (w/v)’luk çözeltileri hazırlanan bu kopolimerlerin elektroeğirme yöntemi ile lifler hazırlanmıştır. Elektroeğirme parametreleri (voltaj, iğne-hedef mesafesi, iğne çapı gibi) değiştirilerek hazırlanan hem nano hem de mikro çaplı fiberler SEM analizleri ile ortaya konmuştur. Ayrıca, Enerji Dağılımlı X-ışını Spektroskopisi (EDX) analizi ile fiberlerde azot atomlarının varlığı ve dağılımının homojenitesi ortaya konmuştur.,It has been demonstrated that oligomers with olefinic end groups are obtained by hydrogen transfer polymerization (HTP). It is also known that these oligomeric structures are functionalized (activated) by chemical modification, the use of this structure as macromonomer and new block copolymers are obtained. In the thesis study, oligomeric structures obtained from acrylamide, methacrylamide and crotonamide by HTP were used as macromonomers. These oligomeric structures and free radical polymerization of hydrophilic vinyl monomers such as acrylic acid, methacrylic acid and crotonic acid one by one were studied in solution environment. In other words, it is aimed to graft macromonomers to homopolymer of vinyl monomer by predicting that olefin-terminated macromonomers and vinyl monomers will be in the same chain in free radical polymerization. Thus, the addition of branches with an amide skeleton to a vinyl polymer ith a carbon skeleton has been achieved. Synthesis of crotonic acid could not be performed in the synthesis of its three macromonomers. In addition, homopolymer (PAA and PMA) could be obtained in the synthesis of poly(β-methyl β-alanine) macromonomer. The synthesis of some of the graft copolymers has been completed. These; poly(acrylic acid-graft-β-alanine), poly(acrylic acid-graft-α-methyl-β-alanine), poly(methacrylic acid-graft-β-alanine) and poly(methacrylic acid-graft-α-methyl-β-alanine) are graft copolymers. Isolation and characterization of these copolymers by FT-IR, elemental, DSC and TGA analysis. Fibers were prepared by electrospinning method of these copolymers with 10% (/v) solution solution for formic acid or mic acid/methanols. By changing the electrospinning (such as voltage, needle-target, needle) both nano and microfibers were revealed by SEM. In addition, the appearance of nitrogen atoms in the fibers and the homogeneity of the predator were revealed by Energy Dispersive X-ray Spectroscopy (EDX) analysis.

It has been demonstrated that oligomers with olefinic end groups are obtained by hydrogen transfer polymerization (HTP). It is also known that these oligomeric structures are functionalized (activated) by chemical modification, the use of this structure as macromonomer and new block copolymers are obtained. In the thesis study, oligomeric structures obtained from acrylamide, methacrylamide and crotonamide by HTP were used as macromonomers. These oligomeric structures and free radical polymerization of hydrophilic vinyl monomers such as acrylic acid, methacrylic acid and crotonic acid one by one were studied in solution environment. In other words, it is aimed to graft macromonomers to homopolymer of vinyl monomer by predicting that olefin-terminated macromonomers and vinyl monomers will be in the same chain in free radical polymerization. Thus, the addition of branches with an amide skeleton to a vinyl polymer ith a carbon skeleton has been achieved. Synthesis of crotonic acid could not be performed in the synthesis of its three macromonomers. In addition, homopolymer (PAA and PMA) could be obtained in the synthesis of poly(β-methyl β-alanine) macromonomer. The synthesis of some of the graft copolymers has been completed. These; poly(acrylic acid-graft-β-alanine), poly(acrylic acid-graft-α-methyl-β-alanine), poly(methacrylic acid-graft-β-alanine) and poly(methacrylic acid-graft-α-methyl-β-alanine) are graft copolymers. Isolation and characterization of these copolymers by FT-IR, elemental, DSC and TGA analysis. Fibers were prepared by electrospinning method of these copolymers with 10% (/v) solution solution for formic acid or mic acid/methanols. By changing the electrospinning (such as voltage, needle-target, needle) both nano and microfibers were revealed by SEM. In addition, the appearance of nitrogen atoms in the fibers and the homogeneity of the predator were revealed by Energy Dispersive X-ray Spectroscopy (EDX) analysis.