Abstract
Nano-TiO2 particles with a range of crystallite sizes were synthesized by a conventional sol-gel method, and then used as nanoparticle substrates in the synthesis of LLDPE/TiO2 nanocomposites via in situ polymerization of ethylene/1-hexene with zirconocene/MMAO catalyst. It was found that the size of the nano-TiO2 crystallite nanoparticles can influence the catalytic activity in the polymerization system. The larger nano-TiO2 crystallites provided better catalytic activity in the polymerization system due to more space for monomer attack. In addition, by thermo-gravimetric analysis, it can be seen that the larger nano-TiO2 crystallites also exhibited lower interaction with available MMAO. Consequently, the MMAO reacted more efficiently with the zirconocene catalyst during the activation process, and enhanced polymerization catalysis. All the polymer nanocomposites products did not have well defined melting temperature indicating non-crystalline polymers. This is due to the high amount of hexene incorporation (based on 13C NMR). The difference in crystallite sizes of the nano-TiO2 also affected how 1-hexene became incorporated into the polymer nanocomposites. The smaller crystallite size of nano-TiO2 allowed greater 1-hexene incorporation due to depression of the reactivity of the ethylene. The contribution of this work helps develop a better understanding of the role of nano-TiO2 in the catalytic activity of the polymerization system and in the microstructure of the polymer composite product. However, this study only considers work on the laboratory scale, so for commercial application of these results, it is necessary to scale up the polymerization process. It is only at this stage, that other physical properties, such as the mechanical properties of these materials can be sensibly determined.
Article PDF
Similar content being viewed by others
Avoid common mistakes on your manuscript.
References
Jordan J, Jacob K I, Tannenbaum R, et al. Experimental trends in polymer nanocomposites-A review. Mater Sci Eng A, 2005, 293: 1–11
Zou H, Wu S, Shen J. Polymer/silica nanocomposites: Preparation, characterization, propertles, and applications. Chem Rev, 2008, 108: 3893–3957
Kontou E, Niaounakis M. Thermo-mechanical properties of LLDPE/SiO2 nanocomposites. Polymer, 2006, 47: 1267–1280
Li K T, Dai C L, Kuo C W. Ethylene polymerization over a nano-sized silica supported Cp2ZrCl2/MAO catalyst. Catal Commun, 2007, 8: 1209–1213
Chen X D, Wang Z, Liao Z F, et al. Roles of anatase and rutile TiO2 nanoparticles in photooxidation of polyurethane. Polym Test, 2007, 26: 202–208
Nussbaumer R J, Caseri W R, Tervoort P T. Polymer-TiO2 nanocomposites: A route towards visually transparent broadband UV filters and high refractive index materials. Macromol Mater Eng, 2003, 288: 44–49
de Fátima V, Marques M, da Silva O, et al. Ethylene polymerization catalyzed by metallocene supported on mesoporous materials. Polym Bull, 2008, 61: 415–423
Zhang Q, He Y Q, Chen X G, et al. Structure and photocatalytic properties of TiO2-graphene oxide intercalated composite. Chin Sci Bull, 2011, 56: 331–339
Kuo M C, Tsai C M, Huang J C, et al. PEEK composites reinforced by nano-sized SiO2 and Al2O3 particulates. Mater Chem Phys, 2005, 90: 185–195
Pitukmanorom P, Ying J Y. Selective catalytic reduction of nitric oxide by propene over In2O3-Ga2O3/Al2O3 nanocomposites. Nano Today, 2009, 4: 220–226
Sagmeister M, Brossmann U, List E J W, et al. Synthesis and optical properties of organic semiconductor: Zirconia nanocomposites. J Nanopart Res, 2010, 12: 2541–2551
Liang R, Deng M, Cui S, et al. Direct electrochemistry and electrocatalysis of myoglobin immobilized on zirconia/multi-walled carbon nanotube nanocomposite. Mater Res Bull, 2010, 45: 1855–1860
Yang D, Ni X, Chen W, et al. The observation of photo-Kolbe reaction as a novel pathway to initiate photocatalytic polymerization over oxide semiconductor nanoparticles. J Photochem Photobiol B, 2008, 195: 323–329
Owpradit W, Jongsomjit B. A comparative study on synthesis of LLDPE/TiO2 nanocomposites using different TiO2 by in situ polymerization with zirconocene/dMMAO catalyst. Mater Chem Phys, 2008, 112: 954–961
Owpradit W, Mekasuwandumrong O, Panpranot J, et al. Synthesis of LLDPE/TiO2 nanocomposites by in situ polymerization with zirconocene/ dMMAO catalyst: Effect of [Al]/[Zr] ratios and TiO2 phases. Polym Bull, 2011, 66: 479–490
Wang C C, Ying J Y. Sol-gel synthesis and hydrothermal processing of anatase and rutile titania nanocrytals. Chem Mater, 1999, 11: 3113–3120
Dominguez A M, Zarate A, Quijada R, et al. Sol-gel iron complex catalysts supported on TiO2 for ethylene polymerization. J Mol Catal A: Chem, 2004, 207: 155–161
Guo N, DiBenedetto S A, Kwon D K, et al. Supported metallocene catalysis for in situ synthesis of high energy density metal oxide nanocomposites. J Am Chem Soc, 2007, 129: 766–767
Qin Y, Dong J. Preparation of nano-compounded polyolefin materials through in situ polymerization technique: Status quo and future prospects. Chin Sci Bull, 2009, 54: 38–45
Fink G, Tesche B, Korber F, et al. The particle forming process of SiO2-supported metallocene catalysts. Macromol Symp, 2001, 173: 77–87
Goretzki R, Fink G, Tesche B, et al. Unusual ethylene polymerization results with metallocene catalysts supported on silica. J Polym Sci Part A: Polym Chem, 1999, 37: 677–682
Chaichana E, Jongsomjit B, Praserthdam P. Effect of nano-SiO2 particle size on the formation of LLDPE/SiO2 nanocomposite synthesized via the in situ polymerization with metallocene catalyst. Chem Eng Sci, 2007, 62: 899–905
Silveira F, Pires G P, Petry C F, et al. Effect of the silica texture on grafting metallocene catalysts. J Mol Catal A-Chem, 2007, 265: 167–176
Giammar D E, Maus C J, Xie L. Effects of particle size and crystalline phase on lead adsorption to titanium dioxide nanoparticles. Environ Eng Sci, 2007, 24: 85–95
Severn J R, Chadwick J C, Duchateau R, et al. “Bound but not gagged”-Immobilizing single-site α-olefin polymerization catalysts. Chem Rev, 2005, 105: 4073–4147
Lingaraju D, Ramji K, Pramila D M, et al. Synthesis, functilization and characterization of silica hybrid nanocomposites. Int J Nanotechnol Appl, 2010, 4: 21–30
Luyt A S, Molefi J A, Krump H. Thermal, mechanical and electrical properties of copper powder filled low-density and linear low-density polyethylene composites. Polym Degrad Stab, 2006, 91: 1629–1636
Hong H, Zhang Z, Chung T C M, et al. Synthesis of new 1-decene-based LLDPE resins and comparison with the corresponding 1-octene- and 1-hexene-based LLDPE resins. J Polym Sci Part A: Polym Chem, 2007, 45: 639–649
Randall J C. A review of high resolution liquid 13carbon nuclear magnetic resonance characterizations of ethylene-based polymers. J Macromol Sci R M C, 1989, 29: 201–317
Hung J, Cole A P, Waymouth R M. Control of sequence distribution of ethylene copolymers: Influence of comonomer sequence on the melting behavior of ethylene copolymers. Macromolecules, 2003, 36: 2454–2463
Xu J T, Zhu Y B, Fan Z Q, et al. Copolymerization of propylene with various higher alpha-olefins using silica-supported rac-Me2Si(lnd)-ZrCl2. J Polym Sci Pol Chem, 2001, 39: 3294–3303
Author information
Authors and Affiliations
Corresponding author
Additional information
This article is published with open access at Springerlink.com
Rights and permissions
This article is published under an open access license. Please check the 'Copyright Information' section either on this page or in the PDF for details of this license and what re-use is permitted. If your intended use exceeds what is permitted by the license or if you are unable to locate the licence and re-use information, please contact the Rights and Permissions team.
About this article
Cite this article
Chaichana, E., Pathomsap, S., Mekasuwandumrong, O. et al. LLDPE/TiO2 nanocomposites produced from different crystallite sizes of TiO2 via in situ polymerization. Chin. Sci. Bull. 57, 2177–2184 (2012). https://doi.org/10.1007/s11434-012-5021-6
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s11434-012-5021-6