Polymerization of heterophasic propylene copolymer with Me2Si(2-Me-4-PhInd)2ZrCl2 supported on SiO2 and SiO2-MgCl2 carriers

• Published in: The Korean journal of chemical engineering Vol. 37; no. 2; pp. 380 - 386
• Main Authors: Encarnacion, Jade Dhalle, Park, Sang Jun, Ko, Young Soo
• Format: Journal Article
• Language: English
• Published: New York Springer US 01.02.2020; Springer Nature B.V; 한국화학공학회
• Subjects: Aluminum compounds; Biotechnology; Catalysis; Catalysts; Chemical industry; Chemistry; Chemistry and Materials Science; Copolymers; Crystallites; Ethylene; Industrial Chemistry; Industrial Chemistry/Chemical Engineering; Magnesium chloride; Materials Science; Melt temperature; Polymer; Polymerization; Polypropylene; Propylene; Silicon dioxide; Surface treatment; 화학공학; SiO; Metallocene Catalyst; Bi-support; Aluminum Alkyl; Heterophasic Copolymerization; MgCl
• ISSN: 0256-1115; 1975-7220
• DOI: 10.1007/s11814-019-0450-4

Me 2 Si(2-Me-4-pbind) 2 ZrCl 2 supported on SiO 2 /MgCl 2 binary support was prepared for the preparation of heterophasic copolymer of polypropylene. The bi-support underwent surface treatment with various alkyl aluminum compounds such as trimethylaluminum (TMA), triethylaluminum (TEAL), and triisobutylaluminum (TIBA) before supporting the metallocene catalyst for 3 or 24 hours and were used for homopolymerization. It was notable that the generated SiO 2 /MgCl 2 bi-support had lower surface area, pore volume and size as compared to the conventional SiO 2 . Impact polypropylene copolymers (IPCs) were obtained using two-step polymerization in one reactor with the presence of metallocene catalyst supported on SiO 2 . Propylene was polymerized in the reactor to produce the iPP matrix followed by polymerization of ethylene resulting to heterophasic material. It is apparent that the molecular weight of the polymer increased with longer PE polymerization time and as the polymerization time was more than 40 min, PP peak appeared near 147.9–149.2 °C, and a new peak emerged at 116.9–119.9 °C which could be attributed to the melting temperature of iPP crystallites and a less intense peak to either chains of ethylene-propylene copolymers. SEM images also confirmed that spherical PE particles were deeply embedded in the crystalline PP matrix and a large amount was produced as the polymerization time of the second stage ethylene polymerization was increased.