Experimental and theoretical approaches for structural and mechanical properties of novel side chain LCP-PP graft coproducts
Yükleniyor...
Dosyalar
Tarih
2016
Dergi Başlığı
Dergi ISSN
Cilt Başlığı
Yayıncı
Erişim Hakkı
info:eu-repo/semantics/openAccess
Özet
The monomers p-biphenyloxycarbonylphenyl acrylate (BPCPA) and p-biphenyloxycarbonylphenyl methacry-late (BPCPMA) were synthesized by the reaction of p-acryloyloxybenzoyl chloride and p-methacryloyloxybenzoyl chloridewith 4-hydroxybiphenyl, respectively, and polymerized by bulk polymerization in vacuum by using dicumyl peroxide.The graft copolymerization of the monomers onto polypropylene were carried out by bulk melt polymerization at 170 °C with various concentration levels of the monomers and the initiator in reaction mixtures. The content of monomers intheir graft coproducts increased with monomer-initiator percentage in the reaction medium. The graft coproducts werecharacterized by several available experimental techniques including differential scanning calorimetry, thermogravimetricanalysis, Fourier transform infrared spectroscopy, scanning electron microscopy, and mechanical testing. Moreover, thecrucial changes in the mechanical performances pertaining to the polypropylene product were investigated by theoreticalcomputations performed based on the density functional theory (B3LYP) with the standard 6-311++G (d,p) level oftheory. According to obtained results, the mechanical properties of the graft coproducts deteriorated signi cantly withthe grafting of the homopolymers due to the damage of the rate-dependent viscoelastic deformation or yielding, leadingto enhancement in the surface energy values. At the same time, experimental evidence con rmed that the poly (BPCPA) materials exhibited much weaker secondary Van der Waals bonds than those in the poly (BPCPMA) products.
Açıklama
Anahtar Kelimeler
Liquid-Crystalline Polymers, Graft Copolymerization, Calculations, Mechanical Properties, Glass Transition
Kaynak
Turkish Journal of Chemistry
WoS Q Değeri
Q3
Scopus Q Değeri
Q3
Cilt
40
Sayı
3
