Bulk oriented nanocomposites of ultrahigh molecular weight polyethylene reinforced with fluorinated multiwalled carbon nanotubes with nanofibrillar structure

Multi-stage process including grinding of fluorinated multi-walled carbon nanotubes (MWCNT) and ultrahigh molecular weight polyethylene (UHMWPE) mixture in a ball mill followed by hot pressing and orientation stretching resulted in UHMWPE tensile strength increase from 21 to 132 MPa or by a factor of 6.3 as compared with pristine bulk UHMWPE. Previously reported in literature tensile strength values of reinforced bulk UHMWPE did not exceed 40 MPa. Fluorinated MWCNT were more efficient in reinforcement than pristine ones. SEM study confirmed that fluorinated nanotubes can act as nucleation agents. Unique lamellar crystalline structure is formed onto the MWCNT surface which can be transformed into nanofibrillar structure under applied stress. Fluorinated MWCNT insertion resulted in an increase of nanofibrils amount due to a filler nucleation ability increase. (C) 2016 Elsevier Ltd. All rights reserved.