I. M. Ward

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The wear and mechanical properties of GUR 1020 (Perplas IMP 2000-2) Ultra High Molecular Weight Polyethylene (UHMWPE) subjected to gamma-irradiation in an atmosphere of acetylene, were evaluated for a range of processing conditions of irradiation, annealing and ageing. The results were compared with those obtained for the virgin UHMWPE material and material(More)
In this study, the wear of ultra high molecular weight polyethylene (UHMWPE) (Grade RCH 1000) crosslinked by gamma irradiation in acetylene was compared to virgin (non-irradiated) UHMWPE using four different wear configurations: (i) unidirectional motion with a smooth counterface, (ii) multidirectional motion with a smooth counterface, (iii) unidirectional(More)
A multi-element constitutive model for a lactide-based shape memory polymer has been developed that represents loading to large tensile deformations, stress relaxation and stress recovery at 60, 65 and 70°C. The model consists of parallel Maxwell arms each comprising neo-Hookean and Eyring elements. Guiu-Pratt analysis of the stress relaxation curves yields(More)
on the stress-relaxed fibers. In these cycles fibers with a new initial length L r were stretched up to the final length L f = 6 L 0 , i.e., up to the elongation e = [(L f ± L r)/L r ] ” 100, and then relaxed at controlled rate. This manuscript describes a process in which glass micro-spheres with a 100 lm diameter self-assemble on a patterned electrode(More)
This paper investigates the benefits of combining roll-drawing and acetylene-enhanced crosslinking to alter the mechanical properties of the ultra high molecular weight polyethylene (UHMWPE) used in total hip and knee replacements, with the aim of improving its resistance to wear. UHMWPE was processed via crosslinking, roll-drawing and a combination of(More)
Longitudinal relaxation (T1) measurements of (19)F, (7)Li, and (1)H in propylene carbonate/LiBF4 liquid electrolytes are reported. Comparison of T1 values with those for the transverse relaxation time (T2) confirm that the measurements are in the high temperature (low correlation time) limit of the T1 minimum. Using data from pulsed field gradient(More)
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