Polymer ultrahigh-molecular-weight polyethylene

Gao. S. and Zeng, Y. (1993a). Surface modification of ultrahigh molecular weight polyethylene fibers by plasma treatment. I. Improving surface adhesion. J. Appi. Polym. Sci. 47, 2065-2071. 

In spite of processing difficulties, some higher-molecular-weight polymers, such as ultrahigh-molecular-weight polyethylene (uhmwpe), are used because of their superior toughness. 

Enhancing the wear resistance of polymers (e.g. ultrahigh molecular weight polyethylene — UHMWPE — used for in vivo implants such as artificial hip joints).256... 

Polymers of MMA, AAc, and MAA were grafted onto an ultrahigh molecular weight polyethylene (UHMWPE) fiber surface after pretreatment with electron beam irradiation [31]. Sundell et al. [32] pretreated a PE film with electron beams to facilitate the graft polymerization of vinyl benzylchloride onto the substrate. The inner surface of porous PE hollow fiber had also been modified by grafting of glycidyl methacrylate (GMA) polymer after electron beam irradiation [33]. 

The findings described above form a basis for our current work that examines the influence of the interphase on the structure and ultimately on the properties of linear polymers. In this chapter we will first show that, depending on the crystallization conditions, the amount of loops or entanglements in the interphase, and thus the deformation behavior of polymers, can be varied. We will initially consider the example of ultrahigh molecular weight polyethylene (UHMW-PE) and the role of entanglements upon its drawability. 

Coughlan, J. J. and Hug, D. P., Ultrahigh Molecular Weight Polyethylene , in Encyclopedia of Polymer Science and Engineering, Wiley-Interscience, John Wiley Sons, New York, 1986, Vol. 6, pp. 490-494. 

Specialty polymers achieve very high performance and find limited but critical use in aerospace composites, in electronic industries, as membranes for gas and liquid separations, as fire-retardant textile fabrics for firefighters and race-car drivers, and for biomedical applications (as sutures and surgical implants). The most important class of specialty plastics is polyimides. Other specialty polymers include polyetherimide, poly(amide-imide), polybismaleimides, ionic polymers, polyphosphazenes, poly(aryl ether ketones), polyarylates and related aromatic polyesters, and ultrahigh-molecular-weight polyethylene (Fig. 14.9). 

As illustrated above, selection of cocatalyst is often predicated on cost. In some cases, however, use of an alternative cocatalyst may transcend the cost factor. This could be because the alternative cocatalyst provides enhanced polymer properties or improved process performance. For example, use of TMAL as cocatalyst in place of TEAL in a gas phase process has been shown to provide linear low density polyethylene with lower hexane extractables and superior film tear strength (14). Ultrahigh molecular weight polyethylene and polyethylene with broader molecular weight distribution can be produced using "isopre-nylaluminum" as cocatalyst (15-17). 

Shen, EW., McKellop, H., and Salovey, R. 1996. Irradiation of chemically crosshnked ultrahigh molecular weight polyethylene. J. Polym. Sci. Part B Polym. Phys. 34 1063. 

Wang, X., Wu, Q., and Qi, Z., Unusual rheological behavior of ultrahigh molecular weight polyethylene/kaolin composites prepared via polymerization-flUing, Polym. Int., 52, 1078-1082 (2003). 

The wear resistance of zirconia is inferior to that of alumina. In ceramic/ceramic combinations the wear rate of zirconia can be significantly higher than that of alumina. In combination with ultrahigh-molecular-weight polyethylene (UHMWPE) excessive wear of the polymer occurs. 

D. Xu, Y. Song, X. Shi, P. Tang, M. Matsuo, Y. Bin, Temperature dependence of lamellae orientation of a branched low molecular weight polyethylene/ultrahigh molecular weight polyethylene blend film under a controlled temperature gradient Polymer 54, 4037-4044 (2013)... 

T.M. Ushakova, E.E. Starchak, V.G. Krasheninnikov, V.G. Grinev, T.A. Ladygina, L.A. Novokshonova, Influence of copolymer fraction composition in ultrahigh molecular weight polyethylene blends with ethylene/1-hexene copolymers on material physical and tensile properties. J. Appl. Polym. Sci. 131, 40151 (2014)... 

S.L. Ruan, P. Gao, X.G. Yang, T.X. Yu, Toughening high performance ultrahigh molecular weight polyethylene using multiwalled carbon nanotubes. Polymer 44, 5643-5654 (2003)... 

Yang CY, Heeger AJ, Cao Y. Microstructure of gel-processed blends of conjugated polymer and ultrahigh molecular weight polyethylene. Polymer 2000 41(11) 4113-8. 

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