Preparation of ultrahigh‐molecular‐weight polyethylene/carbon nanotube nanocomposites with a Ziegler–Natta catalytic system and investigation of their thermal and mechanical properties

Abstract

In this research, ultrahigh-molecular-weight polyethylene (UHMWPE)/multiwalled carbon nanotube (MWCNT) nanocomposites with different nanotube concentrations (0.5, 1.5, 2.5, and 3.5 wt %) were prepared via in situ polymerization with a novel, bisupported Ziegler-Natta catalytic system. Magnesium ethoxide [Mg(OEt) 2 ] and surface-functionalized MWCNTs were used as the support of the catalyst. Titanium tetrachloride (TiCl 4 ) accompanied by triethylaluminum constituted the Ziegler-Natta catalytic system. Preparation of the catalyst and the polymerization were carried out in the slurry phase under an argon atmosphere. Support of the catalyst on the MWCNTs was investigated with Fourier transform infrared spectroscopy. The results confirmed the interaction between the catalyst and the MWCNT hydroxyl groups. Intrinsic viscosity measurements showed an ultrahigh molecular weight in the produced samples. Scanning electron microscopy images confirmed the good dispersion of MWCNTs throughout the polyethylene (PE) matrix. The crystallization behavior of the samples was examined with differential scanning calorimetry. Its results showed that the crystal content of the samples increased with increasing MWCNT concentration up to 1.5 wt %. The same trend was observed for the crystallization temperature, whereas the melting temperature did not change with increasing MWCNT concentration up to 1.5 wt %, but it decreased beyond this concentration. In addition, thermogravimetric analysis results showed that the addition of MWCNTs noticeably improved all of the investigated thermal stability factors of the UHMWPE/MWCNT nanocomposites compared to those of pure PE. The results obtained from tensile testing revealed significant increases in the Young's modulus, yield stress, and ultimate tensile strength. This indicated a tremendous improvement in the mechanical properties of the PE/MWCNT nanocomposites compared to those of pure PE. V C 2012 Wiley Periodicals, Inc. J Appl Polym Sci 125: E453-E461, 2012

UHMWPE/SBA-15 nanocomposites synthesized by in situ polymerization

“…Despite all these efforts, the manufacture of homogenously dispersed nanocomposites from UHMWPE is still a challenging task [8]. The present work aims the synthesis of high performance polyolefin nanocomposites, exhibiting an intimate mixing and combining the advantages of using the mesoporous silica SBA-15 with a single-site bis-(phenoxyimine) titanium dichloride catalyst, the bis [N-(3-tert-butylsalicylidene)-2,3,4,5,6-pentafluoroanilinato] titanium (IV) dichloride (FI catalyst), able to produce UHMWPE.…”

“…An alternative approach for fabrication of homogenously dispersed nanocomposites is in situ polymerization where a good dispersion of the fillers can be obtained, as well as a more effective interaction between the filler particles and the polymer matrix [8,16].…”

Heterogeneous Catalysis on Nanostructured Carbon Material Supported Catalysts

“…383 Ultrahigh-molecular-weight polyethylene/MWCNT nanocomposites with different nanotube concentrations (0.5-3.5 wt%) were prepared in the slurry phase via in situ polymerization with a bi-supported Ziegler-Natta catalytic system. 384 Magnesium ethoxide [Mg(OEt) 2 ] and surface-functionalized CNTs were used as the support of the catalyst. Titanium tetrachloride and triethylaluminium constituted the Ziegler-Natta catalytic system that interacts with CNT hydroxyl groups.…”

Optimization of UHMWPE/Graphene Nanocomposite Processing using Ziegler-Natta Catalytic System via Response Surface Methodology

“…Any substantial or systematic reproduction, redistribution, reselling, loan, sub-licensing, systematic supply, or distribution in any form to anyone is expressly forbidden. Terms & Conditions of access and use can be found at http:// www.tandfonline.com/page/terms-and-conditions INTRODUCTION Ultrahigh molecular weight polyethylene (UHMWPE), is a unique polymer with outstanding physical and mechanical properties (i.e., high strength and stiffness, good fatigue, and wear characteristics), and is widely used in joint replacement prostheses in the human body [1][2][3][4] . However, due to the low surface hardness and poor wear resistance of the polymer, wear particles lead to osteolysis.…”