Ultradrawing properties of ultra‐high molecular weight polyethylene/functionalized carbon nanotube fibers

Abstract

Systemic investigation of the influence of the plain and functionalized carbon nanotube (CNT) contents on the ultradrawing properties of ultrahigh molecular weight polyethylene/carbon nanotubes (UHMWPE/CNTs, FC y ) and UHMWPE/functionalized CNTs (FC fx-y ) as-prepared fibers are reported. In a way similar to those found for the orientation factor values, the achievable draw ratios (D ra ) of the FC y and FC fx-y as-prepared fibers approached a maximum value as their CNT and/or functionalized CNT contents reached their corresponding optimum values. The maximum D ra values obtained for FC fx-0.001 as-prepared fiber specimens prepared at varying maleic anhydride grafted polyethylene (PE -g-MAH )/modified CNTs weight ratios were significantly higher that of the FC 0.0015 as-prepared fiber specimen prepared at the optimum plain CNT content. Tensile property analysis further suggested that excellent orientation and tensile properties of the drawn FC y and FC fx-y fibers can be obtained by ultradraw-ing the fibers prepared at their optimum plain CNT and/or functionalized CNT contents. To understand the interesting orientation, ultradrawing and tensile properties of FC y and FC fx-y fiber specimens, FTIR, specific surface area, and SEM morphology analysis of the plain and functionalized CNTs were performed in this study. POLYM. ENG. SCI., 51:687-696, 2011. ª FIG. 6. Tensile strength and modulus values of FC 0 , FC 0.0005 , FC 0.0001 , FC 0.0015 , FC 0.002 , FC f1-0.0005 , FC f1-0.001 , FC f1-0.0015 , FC f1-0.002 , FC f2-0.0005 , FC f2-0.001 , FC f2-0.0015 , FC f2-0.002 , FC f3-0.0005 , FC f3-0.001 , FC f3-0.0015 , FC f3-0.002 , FC f4-0.0005 , FC f4-0.001 , FC f4-0.0015 and FC f4-0.002 fiber specimens with varying draw ratios.

Ultradrawing properties of ultra-high molecular weight polyethylene/hydrochloric acid treated attapulgite fibers

“…Presumably, incorporation of uniformly dispersed and aligned CNTs in polymer matrix can provide polymer composites with dramatically improved strength and modulus in their machine direction. These expectations have recently been confirmed by a number of studies [26][27][28][29][30][31][32][33][34][35]. Our recent investigation [32][33][34] found that the achievable draw ratios (D ra ) of UHMWPE/carbon nanotubes (CNTs) asprepared fibers prepared near the optimal UHMWPE concentration improve consistently and reach a maximal value as their CNT and/or functionalized CNT contents increase up to an optimal value, respectively.…”

“…These expectations have recently been confirmed by a number of studies [26][27][28][29][30][31][32][33][34][35]. Our recent investigation [32][33][34] found that the achievable draw ratios (D ra ) of UHMWPE/carbon nanotubes (CNTs) asprepared fibers prepared near the optimal UHMWPE concentration improve consistently and reach a maximal value as their CNT and/or functionalized CNT contents increase up to an optimal value, respectively. As evidenced by DSC thermal analysis, CNTs with extremely high specific surface areas can serve as efficient nucleation sites and facilitate the crystallization of UHMWPE molecules into crystals but with low melting temperatures and/or evaluated smaller crystal thickness during their crystallization processes.…”

“…The maximal achievable draw ratios of FA mx as-prepared series fiber specimens and the tensile strengths of the drawn FA mx fiber specimens are significantly higher than those of the corresponding FA x drawn fiber specimens prepared at the same draw ratios and ATPs contents but without purification by sodium hexametaphosphate. The ultimate tensile strength values of the UHMWPE/purified ATPs drawn fibers prepared at the optimal ATP content using one-stage drawing process at 95°C can reach around 3.9 GN m −2 , which is even higher than most of those UHMWPE/functionalized CNTs drawn fibers prepared at the same drawing condition in our previous study [32][33][34]41]. These results clearly suggest that nanofillers with extremely high specific surface areas can act as efficient nucleation sites and significantly improve the achievable draw ratios and ultimate tenacity properties of nanofillers added UHMWPE fibers.…”

Ultrahigh molecular weight polyethylene fibers prepared using conical dies with varying dimensions

“…In fact, tensile strengths and moduli of ultradrawn UHMWPE specimens were found to improve consistently with the increase in achievable draw ratios [10–19]. Investigations [10, 13–22] have been performed to improve the achievable draw ratios ( D ra ) and the corresponding tensile properties of UHMWPE specimens. The drawability of the UHMWPE specimens was found to depend significantly on the compositions of the solutions from which the gel specimens were made [11, 13–22].…”

“…Investigations [10, 13–22] have been performed to improve the achievable draw ratios ( D ra ) and the corresponding tensile properties of UHMWPE specimens. The drawability of the UHMWPE specimens was found to depend significantly on the compositions of the solutions from which the gel specimens were made [11, 13–22]. The D ra values of UHMWPE specimens were found to reduce significantly, when they were prepared from solutions whose concentrations deviated from their critical values, at which the numbers of entanglements in the coherent network structure of the gel specimens were too many or too few to yield the maximum extension of the UHMWPE during the gel‐deformation process [23, 24].…”