Initiation of oxidative degradation in polypropylene reactor powder produced by Ziegler-Natta catalyst. (March 2017)

• Record Type: Journal Article
• Authors: Tobita, Taira; Chammingkwan, Patchanee; Terano, Minoru; Taniike, Toshiaki
• Is Part Of: Polymer degradation and stability. Volume 137(2017.)
• Page Start: 131
• Page End: 137
• Publication Date: 2017-03
• Subjects: Polypropylene -- Ziegler-Natta catalyst -- Oxidative degradation -- Chemiluminescence -- Initial radical; Polymers -- Deterioration -- Periodicals; Stabilizing agents -- Periodicals; Polymères -- Dégradation -- Périodiques; Stabilisants -- Périodiques; 668.9
• DOI: 10.1016/j.polymdegradstab.2017.01.012
• Languages: English
• ISSNs: 0141-3910

Abstract

Abstract: The oxidative degradation of polypropylene reactor powder was studied to clarify the origin of initial radicals that trigger auto-oxidation. Polymerization conditions were found to have direct impacts on the stability of as-synthesized polymer irrespective of catalyst residues and polymer structures. Polypropylene produced under a higher yield condition exhibited a shorter lifetime with a larger amount of oxidative products after air exposure, suggesting the presence of a larger amount of initial radicals. The addition of a nitroxide radical trapping agent drastically enhanced the stability of as-synthesized polymer by passivating the initially formed radicals. Different experimentation approaches revealed that initial radicals are plausibly formed in polymerization.