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The Annals of Otology, Rhinology, and... Jun 1955
Topics: Esophagus; Humans; Polyethylene; Polyethylenes
PubMed: 14388563
DOI: 10.1177/000348945506400209 -
Journal of the Mechanical Behavior of... Apr 2020
Topics: Hip Prosthesis; Materials Testing; Molecular Weight; Polyethylene; Polyethylenes
PubMed: 32174385
DOI: 10.1016/j.jmbbm.2020.103617 -
Polyethylene, a new synthetic plastic for use in surgery; experimental applications in neurosurgery.Journal of the American Medical... Sep 1947
Topics: Humans; Nervous System; Neurosurgery; Neurosurgical Procedures; Plastics; Polyethylene; Polyethylenes
PubMed: 20257753
DOI: 10.1001/jama.1947.02890020012005 -
Journal of Neurosurgery Nov 1950
Topics: Craniotomy; Humans; Polyethylene; Polyethylenes; Plastic Surgery Procedures; Skull
PubMed: 14795253
DOI: 10.3171/jns.1950.7.6.0492 -
Clinical Orthopaedics and Related... Nov 2004Highly cross-linked and melted polyethylene tibial inserts have recently been introduced for clinical use to reduce fatigue damage and adhesive wear in tibial inserts....
Highly cross-linked and melted polyethylene tibial inserts have recently been introduced for clinical use to reduce fatigue damage and adhesive wear in tibial inserts. Other authors have studied the effect of counterface roughness on the wear behavior of polyethylene tibial inserts in knee simulators using femoral components that were roughened artificially. They reported a higher wear rate with highly cross-linked polyethylene than with unirradiated polyethylene tibial inserts. Artificial roughening of femoral components may not be clinically relevant. To evaluate this concern, we studied the wear behavior of highly cross-linked and conventional polyethylene tibial inserts articulating in vitro against surgically retrieved femoral components that had become roughened in vivo. The wear rate of the highly cross-linked polyethylene (5.9 and 6.8 mg/1 million cycles with 100 and 50% serum) was 80% lower than the wear rate of the conventional polyethylene (33.5 and 32.2 mg/1 million cycles with 100 and 50% serum) tibial inserts after 2 million cycles of simulated gait. This study suggests that during in vivo use, scratches that are generated on the femoral components are likely to produce a higher wear rate with both cross-linked and conventional polyethylene than a smooth femoral component, but that this wear rate is likely to be higher with conventional polyethylene than with highly cross-linked polyethylene tibial inserts.
Topics: Femur; Humans; Knee Prosthesis; Materials Testing; Polyethylene; Polyethylenes; Prosthesis Failure; Reoperation; Stress, Mechanical; Surface Properties; Tibia
PubMed: 15534529
DOI: 10.1097/01.blo.0000143801.41885.8b -
Annals of the New York Academy of... Mar 1960
Topics: Bone and Bones; Humans; Musculoskeletal Physiological Phenomena; Osteogenesis; Polyethylene; Polyethylenes
PubMed: 14417248
DOI: 10.1111/j.1749-6632.1960.tb49973.x -
Journal of Biomaterials Science.... 2008The surfaces of high-density or ultra-high-molecular-weight polyethylenes were hydroxylated using a two-step process. The wetting and wear properties of the untreated...
The surfaces of high-density or ultra-high-molecular-weight polyethylenes were hydroxylated using a two-step process. The wetting and wear properties of the untreated (virgin) and surface hydroxylated polyethylenes were compared. The introduction of hydroxyl groups provided an increase in surface hydrophilicity resulting in reduced wear. Hydrophilicity was analyzed by optical analysis of water contact angle. Wear was determined by weight loss under conditions of a reciprocating pin-on-plate apparatus with the panels immersed in water or calf serum. These results suggest that hydroxylation of polyethylene friction-bearing orthopedic surfaces may lead to a longer joint life.
Topics: Biocompatible Materials; Friction; Hydroxides; Hydroxylation; Joints; Molecular Weight; Optics and Photonics; Polyethylene; Surface Properties; Water
PubMed: 18318959
DOI: 10.1163/156856208783719509 -
ACS Applied Materials & Interfaces Mar 2012An easy approach was reported to achieve high mechanical properties of ultrahigh-molecular-weight polyethylene (UHMWPE)-based polyethylene (PE) blend for artificial...
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.
Topics: Calorimetry, Differential Scanning; Crystallization; Elastic Modulus; Friction; Joint Prosthesis; Materials Testing; Microscopy, Electron, Scanning; Polyethylene; Polyethylenes; Tensile Strength; X-Ray Diffraction
PubMed: 22339721
DOI: 10.1021/am201752d -
Journal. Royal Microscopical Society... Dec 1952
Topics: Histological Techniques; Histology; Humans; Polyethylene; Polyethylene Glycols; Polyethylenes; Tunica Media
PubMed: 13085416
DOI: 10.1111/j.1365-2818.1952.tb02336.x -
Nano Letters Jul 2007We present a complete analysis of the structure of polyethylene (PE) nanoparticles synthesized and stabilized in water under very mild conditions (15 degrees C, 40 atm)...
We present a complete analysis of the structure of polyethylene (PE) nanoparticles synthesized and stabilized in water under very mild conditions (15 degrees C, 40 atm) by a nickel-catalyzed polymerization in aqueous solution. Combining cryogenic transmission electron microscopy (cryo-TEM) with X-ray scattering, we demonstrate that this new synthetic route leads to a stable dispersion of individual PE nanoparticles with a narrow size distribution. Most of the semicrystalline particles have a hexagonal shape (lateral size 25 nm, thickness 9 nm) and exhibit the habit of a truncated lozenge. The combination of cryo-TEM and small-angle X-ray scattering demonstrates that the particles consist of a single crystalline lamella sandwiched between two thin amorphous polymer layers ("nanohamburgers"). Hence, these nanocrystals that comprise only ca. 14 chains present the smallest single crystals of PE ever reported. The very small thickness of the crystalline lamella (6.3 nm) is related to the extreme undercooling (more than 100 degrees C) that is due to the low temperature at which the polymerization takes place. This strong undercooling cannot be achieved by any other method so far. Dispersions of polyethylene nanocrystals may have a high potential for a further understanding of polymer crystallization as well as for materials science as, e.g., for the fabrication of extremely thin crystalline layers.
Topics: Cryoelectron Microscopy; Microscopy, Electron, Transmission; Nanoparticles; Polyethylene; Scattering, Small Angle; X-Ray Diffraction
PubMed: 17564476
DOI: 10.1021/nl070859f