Preparation and Characterization of Acrylic Rubber Compounds with Improved Flammability Properties

Abstract

In this study, it was aimed to use polyacrylate rubber compounds as an alternative material to fluorocarbon monomer rubber by increasing their flame retardant properties. For this purpose, rubber compounds were prepared by adding different amounts of halogen-free flame retardant materials (melamine and ammonium polyphosphate) to polyacrylate rubber formulations and the rheological, mechanical and flammability properties of vulcanizates obtained by vulcanization of these compounds were investigated. Important rheological parameters and optimum curing times were determined by rheometer. As a result of the tensile test performed to determine the mechanical properties, it was determined that the prepared polyacrylate rubber vulcanizates showed better tensile strength compared to the fluorocarbon monomer rubber compound. As a result of the limiting oxygen index test performed to examine the flammability properties, it was observed that the LOI value improved significantly with the addition of melamine and ammonium polyphosphate materials, which were fillers that provide flammability properties to polyacrylate rubber formulations, at 8 and 16 phr, respectively. Therefore, it was concluded that this polyacrylate recipe, which had improved flame retardant properties where mechanical strength is important and prepared at relatively affordable cost, could be used as a potential substitute for expensive fluorocarbon monomer rubber compounds.

Keywords

• Acrylic rubber
• Flammability
• Halogen-free flame retardant
• Rubber

Yanmazlık Özellikleri İyileştirilmiş Akrilik Kauçuk Karışımlarının Hazırlanması ve Karakterizasyonu

Abstract

Bu çalışmada poliakrilat kauçuk karışımlarının yanmazlık özellikleri arttırılarak florokarbon monomer kauçuğa alternatif malzeme olarak kullanılması amaçlanmıştır. Bunun için, poliakrilat kauçuk formülasyonlarına farklı miktarlarda halojen içermeyen alev geciktirici malzemeler (melamin ve amonyum polifosfat) eklenerek kauçuk hamurları hazırlanmış ve bu hamurların vulkanizasyonu sonucu elde edilen vulkanizatların reolojik, mekanik ve yanmazlık özellikleri incelenmiştir. Önemli reolojik parametreler ile optimum pişme süreleri reometre ile belirlenmiştir. Mekanik özellikleri belirlemek için yapılan çekme testi sonucunda ise hazırlanan poliakrilat kauçuk vulkanizatlarının florokarbon monomer kauçuk karışımına oranla daha iyi kopma dayanımı gösterdiği belirlenmiştir. Yanmazlık özelliklerini incelemek için yapılan sınırlayıcı oksijen indeksi testi sonucunda ise poliakrilat kauçuk formülasyonlarına yanmazlık özelliği sağlayan dolgular olan melamin ve amonyum polifosfat malzemelerinin sırasıyla 8 ve 16 phr olacak şekilde eklenmesiyle LOI değerinin önemli ölçüde geliştiği görülmüştür. Dolayısıyla mekanik dayanımın önemli olduğu, gelişmiş yanmazlık ve alev geciktirici özelliğe sahip ve nispeten uygun maliyetle hazırlanan bu poliakrilat reçetesinin, pahalı florokarbon monomer kauçuk karışımlarına muadil olarak kullanılabileceği sonucuna varılmıştır.

Keywords

• Akrilik kauçuk
• Halojen içermeyen alev geciktirici
• Kauçuk
• Yanmazlık

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