Effects of molecular weight and molecular weight distribution on creep properties of polypropylene homopolymer
    
Yazarlar (2)
Gokce Kurt Yalova Üniversitesi, Türkiye
Doç. Dr. Alper KAŞGÖZ Yalova Üniversitesi, Türkiye
Makale Türü Özgün Makale (SSCI, AHCI, SCI, SCI-Exp dergilerinde yayınlanan tam makale)
Dergi Adı Journal of Applied Polymer Science (Q2)
Dergi ISSN 0021-8995 Wos Dergi Scopus Dergi
Dergi Tarandığı Indeksler SCI-Expanded
Makale Dili Türkçe Basım Tarihi 08-2021
Cilt / Sayı / Sayfa 138 / 30 / – DOI 10.1002/app.50722
Makale Linki http://dx.doi.org/10.1002/app.50722
Özet
The molecular weights of the industrial-grade isotactic polypropylene (i-PP) homopolymers samples were determined by the melt-state rheological method and effects of molecular weight and molecular weight distribution on solid and melt state creep properties were investigated in detail. The melt-state creep test results showed that the creep resistance of the samples increased by Mw due to the increased chain entanglements, while variations in the polydispersity index (PDI) values did not cause a considerable change in the creep strain values. Moreover, the solid-state creep test results showed that creep strain values increased by Mw and PDI due to the decreasing amount of crystalline structure in the polymer. The results also showed that the amount of crystalline segment was more effective than chain entanglements that were caused by long polymer chains on the creep resistance of the polymers. Modeling the solid-state viscoelastic structure of the samples by the Burger model revealed that the weight of the viscous strain in the total creep strain increased with Mw and PDI, which meant that the differences in the creep strain values of the samples would be more pronounced at extended periods of time.
Anahtar Kelimeler
creep | molecular weight | molecular weight distribution | polypropylene