title: Tuning the superstructure of ultrahigh-molecular-weight polyethylene/low-molecular-weight polyethylene blend for artificial joint application.
abstract: An easy approach was reported to achieve high mechanical properties of ultrahigh-molecular-weight polyethylene (UHMWPE)-based polyethylene (PE) blend for artificial joint application without the sacrifice of the original excellent wear and fatigue behavior of UHMWPE. The PE blend with desirable fluidity was obtained by melt mixing UHMWPE and low molecular weight polyethylene (LMWPE), and then was processed by a modified injection molding technology-oscillatory shear injection molding (OSIM). Morphological observation of the OSIM PE blend showed LMWPE contained well-defined interlocking shish-kebab self-reinforced superstructure. Addition of a small amount of long chain polyethylene (2 wt %) to LMWPE greatly induced formation of rich shish-kebabs. The ultimate tensile strength considerably increased from 27.6 MPa for conventional compression molded UHMWPE up to 78.4 MPa for OSIM PE blend along the flow direction and up to 33.5 MPa in its transverse direction. The impact strength of OSIM PE blend was increased by 46% and 7% for OSIM PE blend in the direction parallel and vertical to the shear flow, respectively. Wear and fatigue resistance were comparable to conventional compression molded UHMWPE. The superb performance of the OSIM PE blend was originated from formation of rich interlocking shish-kebab superstructure while maintaining unique properties of UHMWPE. The present results suggested the OSIM PE blend has high potential for artificial joint application.
authors.affiliation: College of Polymer Science and Engineering and State Key Laboratory of Polymer Materials Engineering, Sichuan University, Chengdu 610065, China.
authors.forename: Ling
authors.initials: L
authors.lastname: Xu
authors.forename: Chen
authors.initials: C
authors.lastname: Chen
authors.forename: Gan-Ji
authors.initials: GJ
authors.lastname: Zhong
authors.forename: Jun
authors.initials: J
authors.lastname: Lei
authors.forename: Jia-Zhuang
authors.initials: JZ
authors.lastname: Xu
authors.forename: Benjamin S
authors.initials: BS
authors.lastname: Hsiao
authors.forename: Zhong-Ming
authors.initials: ZM
authors.lastname: Li
mesh_terms: D002152:Calorimetry, Differential Scanning; D003460:Crystallization; D055119:Elastic Modulus; D017276:Friction; D007595:Joint Prosthesis; D008422:Materials Testing / Q000379:methods*; D008855:Microscopy, Electron, Scanning; D020959:Polyethylene / Q000737:chemistry*; D011095:Polyethylenes / Q000737:chemistry*; D013718:Tensile Strength; D014961:X-Ray Diffraction
chemical_list: D011095:Polyethylenes; C111601:ultra-high molecular weight polyethylene; D020959:Polyethylene