Publication: UV ile sertleşebilen sert hibrit kaplamaların sentezi ve karakterizasyonu
Abstract
Ultraviyole (UV) ile kürlenebilen polimerler, çevre dostu, yüksek işlem hızı, mükemmel film özellikleri, düşük sıcaklık kürü ve enerji verimliliği konusundaki yararları nedeniyle son on yılda büyük ilgi uyandırmıştır. Ayrıca bu polimerler genellikle yüksek çapraz bağlanma yoğunluklarından dolayı üstün mekanik, kimyasal ve ısı direnci sergilemektedirler. Tüm bu sayılan avantajlar nedeniyle cilaların, boyaların, baskı mürekkeplerinin ve yapışkanların hızlı kurutulması gibi uygulamaların yanı sıra gıda ambalajı baskı plakalarının üretiminde de kullanılır. En yaygın kullanılan UV-kürlenebilen reçineler, yüksek reaktivite sergileyen fonksiyonel uç gruplara sahip çok sayıda akrilat bazlı monomer ve oligomerlerdir. Akrilat bazlı reçine sistemleri tipik olarak üç temel bileşenden, yani polimer ağının bel kemiğini oluşturan akrilat işlevselleştirilmiş oligomer, akrilat monomerleri (bir veya daha fazla vinil grubu içeren küçük moleküller) ve UV'ye maruz kalma konusunda serbest radikalleri üreten foto başlatıcıdan oluşur. Üretan akrilatlar, tokluk, esneklik, kimyasal direnç ve hava geçirgenliği gibi olağanüstü fiziksel ve mekanik özellikler sergileyen en önemli UV iyileştirilebilir oligomerler arasındadır.Hibrit kaplamaların hazırlanmasında ise en yaygın yöntem sol-jel yöntemidir. Bu yöntemle hazırlanan kaplamalar organik ve inorganik polimerlerin özelliklerini tek bir yapı altında bulundurur. Yapı içinde organik kısım, darbe direnci ve yapışma özellikleri, inorganik kısım ise yapışmanın yanında yüksek sertlik ve aşınma direncini sağlamaktadır.Bu çalışmada organik-inorganik hibrit üretan akrilat reçinesi; organik üretan akrilik oligomerinin sentezi ve bu organik reçine içerisine farklı yüzdelerde viniltrimetoksi silan (Si-MEt) eklenmesiyle hazırlanmıştır. Üretan akrilik oligomerinin yanı sıra yüksek derecede çapraz bağlanma ile daha yoğun organik ağ yapısı elde etmek için fonksiyonel reaktif akrilikler (TMPTA, HDDA) kullanılmıştır. UV ile kürlenebilen, sert ve şeffaf hibrit kaplaması PMMA (polimetilmetakrilat) yüzeylerine uygulanarak kalem sertlik, pendulum sertlik, parlaklık (60o), çapraz-kesme, MEK ile ovma, taber aşınma, çekme, temas açısı testi gibi farklı fiziksel testler ve FT-IR, DSC, SEM karakterizasyon testleri yapılmıştır. Çalışmalar sonucunda PMMA (polimetilmetakrilat) yüzeyinin çizilmeye ve aşınmaya karşı direnci arttırılmıştır.
Ultraviolet (UV) curable polymers have attracted great interest in the last decade due to their environmentally friendly, high processing speed, excellent film properties, low temperature curing and energy efficiency benefits. Furthermore, these polymers generally exhibit superior mechanical, chemical and heat resistance due to their high crosslinking densities. Because of all these advantages, it is used in the production of food packaging printing plates as well as applications such as fast drying of varnishes, paints, printing inks and adhesives. The most commonly used UV-curable resins are a large number of acrylate-based monomers and oligomers with functional end groups that exhibit high reactivity. Acrylate-based resin systems typically consist of three basic components, ie the acrylate functionalized oligomer, acrylate monomers (small molecules containing one or more vinyl groups) that form the backbone of the polymer network, and a photoinitiator that produces free radicals for UV exposure. Urethane acrylates are among the most important UV curable oligomers that exhibit outstanding physical and mechanical properties such as toughness, flexibility, chemical resistance and air permeability.The most common method for the preparation of hybrid coatings is sol-gel. The coatings prepared by this method have the properties of organic and inorganic polymers under a single structure. In the structure, organic part provides impact resistance and adhesion properties while inorganic part provides high hardness and abrasion resistance besides adhesion.In this study, organic-inorganic hybrid urethane acrylate resin was prepared by synthesizing the organic urethane acrylic oligomer and adding different percentages of vinyltrimethoxy silane (Si-MEt) into this organic resin. In addition to the urethane acrylic oligomer, functional reactive acrylics (TMPTA, HDDA) were used to obtain a dense organic network structure with high crosslinking. The UV-curable, hard and transparent hybrid coating was applied to the surface of PMMA (polymethylmethacrylate) and subjected to different physical tests such as pencil hardness, pendulum hardness, gloss (60o), cross-cut, MEK rubbing, taber abrasion, tensile and contact angle test and FT-IR, DSC, SEM characterization tests. As a result of these studies, the resistance of PMMA (polymethylmethacrylate) to scratch and abrasion was increased.
Ultraviolet (UV) curable polymers have attracted great interest in the last decade due to their environmentally friendly, high processing speed, excellent film properties, low temperature curing and energy efficiency benefits. Furthermore, these polymers generally exhibit superior mechanical, chemical and heat resistance due to their high crosslinking densities. Because of all these advantages, it is used in the production of food packaging printing plates as well as applications such as fast drying of varnishes, paints, printing inks and adhesives. The most commonly used UV-curable resins are a large number of acrylate-based monomers and oligomers with functional end groups that exhibit high reactivity. Acrylate-based resin systems typically consist of three basic components, ie the acrylate functionalized oligomer, acrylate monomers (small molecules containing one or more vinyl groups) that form the backbone of the polymer network, and a photoinitiator that produces free radicals for UV exposure. Urethane acrylates are among the most important UV curable oligomers that exhibit outstanding physical and mechanical properties such as toughness, flexibility, chemical resistance and air permeability.The most common method for the preparation of hybrid coatings is sol-gel. The coatings prepared by this method have the properties of organic and inorganic polymers under a single structure. In the structure, organic part provides impact resistance and adhesion properties while inorganic part provides high hardness and abrasion resistance besides adhesion.In this study, organic-inorganic hybrid urethane acrylate resin was prepared by synthesizing the organic urethane acrylic oligomer and adding different percentages of vinyltrimethoxy silane (Si-MEt) into this organic resin. In addition to the urethane acrylic oligomer, functional reactive acrylics (TMPTA, HDDA) were used to obtain a dense organic network structure with high crosslinking. The UV-curable, hard and transparent hybrid coating was applied to the surface of PMMA (polymethylmethacrylate) and subjected to different physical tests such as pencil hardness, pendulum hardness, gloss (60o), cross-cut, MEK rubbing, taber abrasion, tensile and contact angle test and FT-IR, DSC, SEM characterization tests. As a result of these studies, the resistance of PMMA (polymethylmethacrylate) to scratch and abrasion was increased.