Çok dallanmış polimerlerin İniferter yöntemiyle kontrollü olarak sentezi
Yükleniyor...
Dosyalar
Tarih
2023
Yazarlar
Dergi Başlığı
Dergi ISSN
Cilt Başlığı
Yayıncı
Bursa Teknik Üniversitesi, Lisansüstü Eğitim Enstitüsü
Erişim Hakkı
info:eu-repo/semantics/openAccess
Özet
Son yıllarda tıp, biyomedikal, tekstil, boya gibi birçok alanda insan yaşamını doğrudan etkileyen birçok gelişme yaşanmıştır. Bu gelişmelere kaynak oluşturan ana faktörlerden biri polimerik malzemelerde ortaya çıkan gelişmelerdir. Yaşanan bu gelişmeler polimerlerin yaygın kullanım alanlarının daha da genişlemesine neden olmuştur. Öte yandan, çok üstün özelliklere sahip olmalarına rağmen, henüz endüstriyel kullanımı bulunmayan ve sadece laboratuvar ölçeğinde üretimi yapılabilen, birçok yüksek teknoloji polimerik malzeme de bulunmaktadır. Böylesi endüstriyel uyarlamaların yapılamamasının temel nedeni, bu malzemelerin üretim proseslerinin zor ve çok basamaklı oluşundan kaynaklı olarak, endüstriyel üretimlerinde karşılaşılan yüksek maliyetidir. Bu bağlamda, yüksek teknoloji polimerlerin basit ve düşük maliyetli yöntemlerle eldesine imkân veren yeni sentez yöntemlerinin geliştirilmesi son yıllarda giderek önem kazanmıştır. Önemli bir polimer mimarisi olan çok dallanmış polimerler de sağladıkları avantajlardan dolayı son dönemlerde giderek önem kazanmıştır. Çok dallanmış polimerlerin eldesi birçok yöntem olmakla birlikte, bu yöntemlerden kendiliğinden yoğunlaşan vinil polimerizasyon (SCVP) yöntemi en yaygın kullanıma sahip olan yöntemdir. Farklı kontrollü polimerizasyon yöntemlerinin SCVP yöntemine uyarlanması ile birçok polimer sentezi gerçekleştirilmiştir. Tez kapsamında yapılan çalışmalar ile dallanma yoğunluğu kontrol edilebilir çok dallanmış polimerin eldesi için, SCVP ve iniferter proseslerini birleştiren yeni bir sentetik yaklaşım ortaya konulmuştur. Bu kapsama ayarlanabilir dallanma yoğunluklarına sahip polistiren bazlı çok dallanmış polimerlerin (çd-PS) sentezi için çok yönlü bir yaklaşım rapor edilmiştir. Teknik, hem polimerize edilebilir hem de inferter birimleri içeren iki fonksiyonel bir monomer olan 2,2,2-(trifeniletil)stirenin (TPES) kullanımına dayanmaktadır. Dallanmayı sağlayan türün TPES olduğu göz önünde bulundurulduğunda, TPES oranının değiştirilmesi ile farklı dallanma derecelerine sahip polimerler elde edilmiştir. Ayrıca sürenin polimerizasyon üzerindeki etkisi de incelenmiştir. Çalışma kapsamında ilk olarak inimer (TPES) sentezi iki basamakta bir prosedür ile gerçekleştirilmiştir. Elde edilen TPES, stiren ile toluen içerisinde farklı oranlarda kopolimerleştirilip, çok dallanmış polimerler elde edilmiştir. Bu polimerleştirme basamağı kendiliğinden yoğunlaşan vinil polimerizasyon yöntemiyle gerçekleştirilmiş. Ayrıca elde edilen polimerler, amfifilik dallı çekirdekli yıldız polimerleri vermek üzere bir hidrofilik monomerin poli(etilen glikol)akrilat) (PEGA) kopolimerizasyonu için makroiniferter olarak kullanılmıştır. Bu çerçevede hidrofobik PS çekirdekli ve hidrofilik PEGA kabuğa sahip amfifilik dallı kopolimerler sentezlenmiştir. Öncü, çok dallanmış ve elde edilen amfifilik kopolimerler yapıları 1H NMR, FT-IR, GPC ve su temas açısı (WCA) ölçümleri ile karakterize edilmiştir.
In recent years, there have been many developments that directly affect human life in many fields such as medicine, biomedical, textile, paint. One of the main factors contributing to these developments is the developments in polymeric materials. These developments have led to the expansion of the common usage areas of polymers. On the other hand, there are many high-tech polymeric materials that, although they have very superior properties, have not yet been used industrially and can only be produced on a laboratory scale. The main reason why such industrial adaptations cannot be made is the high cost encountered in industrial production due to the difficult and multi-step production processes of these materials. In this context, the development of new synthesis methods that allow high-tech polymers to be obtained by simple and low-cost methods has become increasingly important in recent years. Highly branched polymers, which are an important polymer architecture, have gained importance in recent years due to the advantages they provide. Although there are many methods to obtain hyper branched polymers, the self-condensing vinyl polymerization (SCVP) method is the most widely used method. Many polymers have been synthesized by adapting different controlled polymerization methods to the SCVP method. With the studies carried out within the scope of the thesis, a new synthetic approach combining SCVP and iniferter processes has been introduced to obtain highly branched polymer with controllable branching density. A versatile approach for the synthesis of polystyrene based hyperbranched polymers (hyp-PS) with tunable branching densities by combination of self-condensing vinyl polymerization and iniferter processes is reported. The technique is based on the utilization of a dual functional monomer, 2,2,2-(triphenylethyl)styrene (TPES), that contains both polymerizable and iniferter units. Considering that the type that provides branching is TPES, polymers with different degrees of branching were obtained by changing the TPES ratio. In addition, the effect of time on polymerization was also investigated. Within the scope of the study, firstly, the synthesis of inimers (TPES) was carried out with a two-step procedure. The obtained TPES was copolymerized with styrene in toluene at different rates and highly branched polymers were obtained. This polymerization step was carried out by the self-condensing vinyl polymerization method. Moreover, obtained polymers are used as macroiniferter for the copolymerization of a hydrophilic monomer (poly(ethylene glycol) acrylate) to give amphiphilic branched-core star polymers. In this framework, amphiphilic branched copolymers with hydrophobic PS core and hydrophilic PEGA shell were synthesized. The leading, highly branched and resulting amphiphilic copolymers structures were characterized by 1H NMR, FT-IR, GPC and (WCA) measurements.
In recent years, there have been many developments that directly affect human life in many fields such as medicine, biomedical, textile, paint. One of the main factors contributing to these developments is the developments in polymeric materials. These developments have led to the expansion of the common usage areas of polymers. On the other hand, there are many high-tech polymeric materials that, although they have very superior properties, have not yet been used industrially and can only be produced on a laboratory scale. The main reason why such industrial adaptations cannot be made is the high cost encountered in industrial production due to the difficult and multi-step production processes of these materials. In this context, the development of new synthesis methods that allow high-tech polymers to be obtained by simple and low-cost methods has become increasingly important in recent years. Highly branched polymers, which are an important polymer architecture, have gained importance in recent years due to the advantages they provide. Although there are many methods to obtain hyper branched polymers, the self-condensing vinyl polymerization (SCVP) method is the most widely used method. Many polymers have been synthesized by adapting different controlled polymerization methods to the SCVP method. With the studies carried out within the scope of the thesis, a new synthetic approach combining SCVP and iniferter processes has been introduced to obtain highly branched polymer with controllable branching density. A versatile approach for the synthesis of polystyrene based hyperbranched polymers (hyp-PS) with tunable branching densities by combination of self-condensing vinyl polymerization and iniferter processes is reported. The technique is based on the utilization of a dual functional monomer, 2,2,2-(triphenylethyl)styrene (TPES), that contains both polymerizable and iniferter units. Considering that the type that provides branching is TPES, polymers with different degrees of branching were obtained by changing the TPES ratio. In addition, the effect of time on polymerization was also investigated. Within the scope of the study, firstly, the synthesis of inimers (TPES) was carried out with a two-step procedure. The obtained TPES was copolymerized with styrene in toluene at different rates and highly branched polymers were obtained. This polymerization step was carried out by the self-condensing vinyl polymerization method. Moreover, obtained polymers are used as macroiniferter for the copolymerization of a hydrophilic monomer (poly(ethylene glycol) acrylate) to give amphiphilic branched-core star polymers. In this framework, amphiphilic branched copolymers with hydrophobic PS core and hydrophilic PEGA shell were synthesized. The leading, highly branched and resulting amphiphilic copolymers structures were characterized by 1H NMR, FT-IR, GPC and (WCA) measurements.
Açıklama
Anahtar Kelimeler
Polimer Bilim ve Teknolojisi, Polymer Science and Technology
