Novel stabilization system for polypropylene via the Ziegler–Natta catalyzed polymerization in the presence of aluminum aryloxide

Abstract

ABSTRACT:The aluminum aryloxide was prepared via the reaction of phenolic antioxidant, 3-(3,5-di-t-butyl-4-hydroxyphenyl)-N-octadecylpropionamide, with triethyl aluminum. Propylene polymerization using supported ZieglerNatta catalyst systems was carried out in the presence of the antioxidant or its aluminum aryloxide. Although the antioxidant gave rise to decrease in catalyst yield and change in hydrogen response, the aluminum aryloxide had no influence on the catalytic polymerization behavior, and thus the obtained polymer characteristics such as molecular weight, polydispersity, and meso pentad as a stereoregularity were comparable to that polymerized without the antioxidant and the aluminum aryloxide. Polypropylene obtained in the presence of the aluminum aryloxide was well stabilized for oxidation and its stability was over 1000 h at 100°C (estimated to be over 30 years at room temperature).

Physical and mechanical properties of poly(L‐lactic acid) nucleated by dibenzoylhydrazide compound

“…15,16,[24][25][26] In most cases, nucleated PP is used for the applications, which need higher stiffness and heat resistance. The stiffness, heat resistance, and processability of nucleated PP is considered to be a targeted value for nucleated PLA from the viewpoint of evaluating the possibility and applicability as molded articles of the nucleated PLA.…”

Effect of different additives and their mixtures on thermal stability of polyethylene synthesized using iron and titanocene hybrid catalysts

“…The presence of additives can also disturb monomer recovery process. Because of these technical problems which are not favorable from an industrial point of view, in recent years, few investigations have been reported on the use of antioxidants in the polymerization of propylene, and their effect and chemical structures on the activity of catalyst and properties of the final products. Antioxidants are categorized into primary and secondary classes.…”

“…In the phenolic antioxidants, hydroxyl group decreases the catalyst activity through its reaction with catalyst. Therefore, before polymerization, the hydroxyl group needs to react with alkyl aluminum and be converted to aryl oxide groups . Irganox 1330, a phenolic (primary) antioxidant with no ester group in its chemical structure, has a better performance in comparison to those phenolic antioxidants having ester group, because ester groups of antioxidants are capable to interact with the catalyst, and consequently decrease its activity .…”

Study on propylene polymerization in the presence of phenolic antioxidant (Irganox 1076) and characterization of stabilized polymers

“…Conventionally, AOs and additives are mixed with PP by extruder, thereby producing pellets . Pelletizing consumes the huge energy that reported about one‐third of the total energy of PP production .…”