Effect of NH3/methylaluminoxane/dodecylamine modifiednanoclay on morphology and properties of polyethylene/ clay nanocomposites prepared by in-situ polymerization

Document Type: Original research


Iran Polymer and Petrochemical Institute, Tehran, Iran


This study presents methods for treating a kind of nanoclay and investigates the effects of methylaluminoxane (MAO) exposure time and or dodecylamine (DDA) reflux time on in-situ polymerization of ethylene in the presence of nanoclay and examines the morphology and properties of the prepared polyethylene/clay nanocomposites. The results revealed that by increasing MAO exposure time productivity decreased. Modification of nanoclay by NH3/MAO led to formation of exfoliated structures. In treatment with NH3/DDA, the change in reflux time resulted in different structures. SEM demonstrated that the morphology of the nanocomposites strongly depended on the modification method and treatment time. Dynamic mechanical analysis indicated that the elastic modulus of the nanocomposites increased by increasing MAO exposure time. The nanocomposites treated with different MAO exposure times showed similar thermal degradation behavior. The nanocomposite modified under the condition of 24 h DDA reflux time indicated the lowest thermal decomposition temperature due to poor dispersion of nanoclay in the synthesized nanocomposite. The nanocomposites modified by NH3/MAO had higher degree of crystallinity compared to those modified by NH3/DDA, which could be attributed to the difference in dispersion level of the modified clays. A relationship between the rheological properties, weight fraction and dispersion of modified nanoclay was observed. The findings showed that the modification condition had a significant influence on the morphology and properties of the synthesized nanocomposites.


Main Subjects

  1. Panupakorn P, Chaichana E, Praserthdam P, Jongsomjit B (2013) Polyethylene/clay nanocomposites produced by in situ polymerization with zirconocene/MAO catalyst. J Nanomater 2013: 1–9
  2. Nikkhah SJ, Ramazani SA A, Baniasadi H, Tavakolzadeh F (2009) Investigation of properties of polyethylene/clay nanocomposites prepared by new in situ Ziegler–Natta catalyst. Mater Des 30: 2309–2315
  3. Peacock A (2000) Handbook of polyethylene: structures: Properties, and applications. CRC Press
  4. Taguet A, Cassagnau P, Lopez-Cuesta JM (2014) Structuration, selective dispersion and compatibilizing effect of (nano) fillers in polymer blends. Prog Polym Sci 39: 1526–1563
  5. Das R, Banerjee SL, Kundu PP (2016) Fabrication and characterization of in situ graphene oxide reinforced high-performance shape memory polymeric nanocomposites from vegetable oil. RSC Adv 6: 27648–27658
  6. Yazdaninia A, Khonakdar HA, Jafari SH, Asadi V (2016) Influence of trifluoropropyl-POSS nanoparticles on the microstructure, rheological, thermal and thermomechanical properties of PLA. RSC Adv 6: 37149–37159
  7. Chen T, Yang H, Li W (2015) Phase structure and mechanical properties of disentangled ultra-high molecular weight polyethylene/polyhedral oligomeric silsesquioxane nanocomposites in a solid state. J Polym Res 22: 1–8
  8. Zanjanijam AR, Bahrami M, Hajian M (2016) Poly (vinyl chloride)/single wall carbon nano-tubes composites: Investigation of mechanical and thermal characteristics. J Vinyl Addit Technol 22: 128-133
  9. Cai D, Song M (2015) Ultra-high enhancement in the toughness of polyethylene by exfoliated natural clay nanosheets. J Appl Polym Sci 132: 41314
  10. Sánchez-Valdes S, Ramírez-Vargas E, Ramos de Valle LF, Martinez-Colunga JG, Romero-Garcia J, Ledezma-Perez AS, Mendez-Nonell J, Castañeda-Flores ME, Morales-Cepeda A (2016) Physical and mechanical properties of linear low density polyethylene/cycloolefin copolymer/layered silicate nanocomposite. Polym Compos 37: 3167-3174
  11. Trifkovic M, Hedegaard AT, Sheikhzadeh M, Huang S, Macosko CW(2015) Stabilization of PE/PEO Cocontinuous Blends by Interfacial Nanoclays. Macromolecules 48:4631-4644
  12. Raji M, Essabir H, Essassi EM, El Mokhtar Essassi, Rodrigue D, Bouhfid R, Qaiss AK (2016) Morphological, thermal, mechanical, and rheological properties of high density polyethylene reinforced with Illite clay. Polym Compos: 10.1002/PC.24096
  13. Zare Y (2015) Estimation of material and interfacial/interphase properties in clay/polymer nanocomposites by yield strength data. Appl Clay Sci 115:61-66
  14. Singh VP, Kapur GS, Choudhary V (2016) High-density polyethylene/needle-like sepiolite clay nanocomposites: Effect of functionalized polymers on the dispersion of nanofiller, melt extensional and mechanical properties. RSC Adv 6:59762-59774
  15. Hakim S, Safajou-Jahankhanemlou M, Zeynali ME (2013) Polyethylene nanocomposite pre-pared by a metallocene catalyst supported on MMT using a new pretreatment method. J Polym Res 20:1-10
  16. Ramazani SA A, Tavakolzadeh F (2008) Preparation of polyethylene/layered silicate nanocomposites using in situ polymerization approach. Macromol Symp 274: 65-71
  17. Maneshi A, Soares JBP, Simon LC (2006) A Single-gallery model for the in situ production of polyethylene/clay nanocomposites. Macromol Symp 243: 277-286
  18. Kaminsky W (2014) Metallocene based polyolefin nanocomposites. Materials 7:1995–2013
  19. Maneshi A, Soares JBP, Simon LC (2011) An efficient in situ polymerization method for the production of polyethylene/clay nanocomposites: Effect of polymerization conditions on particle morphology. Macromol Chem Phys 212:2017–2028
  20. Zapata PA, Belver C, Quijada R, Aranda P, Ruiz-Hitzky E (2013) Silica/clay organo-heterostructures to promote polyethylene–clay nanocomposites by in situ polymerization. Appl Catal A-Gen 453:142-150
  21. Herrero M, Núñez K, Gallego R, CarlosMerino J,Pastor JM (2016) Control of molecular weight and polydispersity in polyethylene/needle-like shaped clay nanocomposites obtained by in situ polymerization with metallocene catalysts. Eur Polym J 75:125-141
  22. Carrero A, van Grieken R, Suarez I, Paredes B (2012) Development of a new synthetic method based on in situ strategies for polyethylene/clay composites. J Appl Polym Sci 126:987-997
  23. Xalter R, Pelascini F, Mülhaupt R (2008) Ethylene polymerization, on-line particle growth monitoring, and in situ nanocomposite formation using catalysts supported on arylsulfonic acid-modified boehmites. Macromolecules 41:3136-3143
  24. Abedi S, Abdouss M, Daftari-Besheli M, Min KE, Seo KH, Noh SK(2013) Highly exfoliated PE/Na+ MMT nanocomposite produced via in situ polymerization by a catalyst supported on a novel modified Na+ MMT. Polym Bull 70:2783-2792
  25. Abedi S, Abdouss M, Nekoomanesh-Haghighi M, Sharifi-Sanjani N (2013) New clay-supported Ziegler–Natta catalyst for preparation of PE/Clay nanocomposites via in situ polymerization. J Appl Polym Sci 128:1879-1884
  26. Maneshi A, Soares JBP, Simon LC (2011) Polyethylene/clay nanocomposites made with metallocenes supported on different organoclays. Macromol Chem Phys 212:216-228
  27. Scott SL, Peoples BC, Yung C, Rojas RS, Khanna V, Sano H, Suzukie T, Shimizu F (2008) Highly dispersed clay–polyolefin nanocomposites free of compatibilizers, via the in situ polymerization of α-olefins by clay-supported catalysts. Chem Commun 4186-4188
  28. Zapata P, Quijada R, Covarrubias C, Moncada E, Retuert J (2009) Catalytic activity during the preparation of PE/clay nanocomposites by in situ polymerization with metallocene catalysts. J Appl Polym Sci 113:2368-2377
  29. Lee D, Kim H, Yoon K, Min KE, Seo KH, Noh SK (2005) Polyethylene/MMT nanocomposites prepared by in situ polymerization using sup-ported catalyst systems. Sci Technol Adv Mater 6:457-462
  30. Huang Y, Yang K, Dong J (2006) Copolymer-ization of ethylene and 10-undecen-1-ol using a montmorillonite-intercalated metallocene catalyst: synthesis of polyethylene/montmorillonite nanocomposites with enhanced structural stability. Macromol Rapid Commun 27:1278-1283
  31. Ren C, Du X, Ma L, Wang Y, Tang T (2010) The role of polymerizable organophilic clay during preparing polyethylene nanocomposite via filling polymerization. J Appl Polym Sci 117:1646-1657
  32. Liu C, Tang T, Huang B (2004) Zirconocene catalyst well spaced inside modified montmorillonite for ethylene polymerization: Role of pretreatment and modification of montmorillonite in tailoring polymer properties. J Catal 221:162-169
  33. Ren C, Du X, Ma L, Wang Y, Zheng J, Tang T (2010) Preparation of multifunctional supported metallocene catalyst using organic multifunctional modifier for synthesizing polyethylene/clay nanocomposites via in situ intercalative polymerization. Polymer 51: 3416-3424
  34. Leone G, Bertini F, Canetti M, Boggioni L, Stagnaro P, Tritto I (2008) In situ polymerization of ethylene using metallocene catalysts: Effect of clay pretreatment on the properties of highly filled polyethylene nanocomposites. J Polym Sci Pol Chem 46:5390-5403
  35. Ray S, Galgali G, Lele A, Sivaram S (2005) In-situ polymerization of ethylene with bis (imino) pyridine iron (II) catalysts supported on clay: the synthesis and characterization of polyethylene–clay nanocomposites. J Polym Sci Pol Chem 43:304-318
  36. Huang Y, Yang K, Dong J-Y (2007) An in situ matrix functionalization approach to structure stability enhancement in polyethylene/montmorillonite nanocomposites prepared by intercalative polymerization. Polymer 48: 4005-4014
  37. Liu C, Tang T, Zhao Z, Huang B (2002) Preparation of functionalized montmorillonites and their application in supported zirconocene catalysts for ethylene polymerization. J Polym Sci Pol Chem 40:1892-1898
  38. Jeong DW, Hong DS, Cho HY, Woo SI (2003) The effect of water and acidity of the clay for ethylene polymerization over Cp2ZrCl2 supported on TMA-modified clay materials. J Mol Catal A-Chem 206:205-211
  39. Novokshonova LA, Kovaleva NY, Ushakova TM, Meshkova IN, Krasheninnikov VJ, LadyginaI TA, Leipunskii O, Zhigach AN, Kuskov ML (2005) Partially hydrolyzed alkylaluminums as the active heterogenized components of metallocene catalysts. Kinet Catal 46:853-86
  40. Weiss K, Wirth-Pfeifer C, Hofmann M, Botzenhardt S, Lang H, Brüning K, Meichel E (2002) Polymerisation of ethylene or propylene with heterogeneous metallocene catalysts on clay minerals. J Mol Catal A-Chem 182:143-149
  41. Suga Y, Maruyama Y, Isobe E, Suzuki T, Shimizu F (1994) Catalyst for polymerizing an olefin and method for producing an olefin polymer. US 5308811 A
  42. Alikhani A, Hakim S, Nekoomanesh M (2017) Modified preparation of HDPE/clay nanocomposite by in situ polymerization using a metallocene catalyst. Iran Polym J 26: 721-731
  43. Huang Y, Qin Y, Dong J, Zhao X, Hu X(2012) PE/OMMT nanocomposites prepared by in situ polymerization approach: Effects of OMMT-intercalated catalysts and silicate modifications. J Appl Polym Sci 123:3106–3116
  44. Maneshi A (2010) In-situ ethylene polymeriza-tion with organoclay-supported metallocenes for the preparation of polyethylene-clay nanocomposites. PhD Thesis, University of Waterloo, Ontario, Canada
  45. Kiliaris P, Papaspyrides CD (2010) Polymer/layered silicate (clay) nanocomposites: an overview of flame retardancy. Prog Polym Sci 35:902-958
  46. Jamshidi S (2014) Mechanical, rheological and thermal properties of polyethylene (PE)/clay nanocomposite for rotomolded containers. Master Thesis, University of Calgary, Canada
  47. Zhao C, Qin H, Gong F, Feng M, Zhang S, Yang M (2005) Mechanical, thermal and flammability properties of polyethylene/clay nanocomposites. Polym Degrad Stab 87:183-189
  48. Jahani Y, Valavi A, Ziaee F (2015) Reactive melt modification of polyethylene by ethyl acrylate/acrylic acid copolymers: Rheology, morphology and thermal behavior. Iran Polym J 24:449-458
  49. Ma J, Zhang S, Qi Z, et al (2002) Crystallization behaviors of polypropylene/montmorillonite nanocomposites. J Appl Polym Sci 83:1978-1985
  50. Xie Y, Yu D, Kong J, Fan X, Qiao W (2006) Study on morphology, crystallization behaviors of highly filled maleated polyethylene-layered silicate nanocomposites. J Appl Polym Sci 100:4004-4011
  51. Lee J-H, Jung D, Hong C-E, et al (2005) Properties of polyethylene-layered silicate nanocomposites prepared by melt intercalation with a PP-g-MA compatibilizer. Compos Sci Technol 65:1996-2002
  52. Hyun YH, Lim ST, Choi HJ, Jhon MS (2001) Rheology of poly (ethylene oxide)/organoclay nanocomposites. Macromolecules 34:8084-8093