Ilyasov, et al., 1:12 Open Access Scientific Reportsof mechanical activation of...
2
Open Access Ilyasov, et al., 1:12 http://dx.doi.org/10.4172/scientificreports.561 Research Article Open Access Open Access Scientific Reports Scientific Reports Open Access Volume 1 • Issue 12 • 2012 Keywords: Ultra high molecular weight polyethylene; Styrene; Maleic anhydride; Nanofiller; Aluminium oxide; Wear resistance; Mechanical properties Introduction In recent years, considerable interest are composites based on ultra- high molecular weight polyethylene (UHMWPE) [1,2]. e formation of the functional properties of the composites is significantly affected by the modification of nanofibers and nanoparticles UHMWPE at low concentrations (0.1-0.5%) [3]. It is known that the modification of polymers are widely used graſt copolymers [4], mixing them with other components of the mixture (in the case of the reaction) leads to an improvement of interfacial interaction [5]. Chemical modification of UHMWPE significantly increases its wear resistance, due to peculiarities of crystallization and the formation of the supramolecular structure of the polymer [1]. e incompleteness of the data on the peculiarities of formation of the functional properties of the polymer-polymer composites based on UHMWPE, while the influence of the different contents of graſted UHMWPE and fillers in the form of oxide aluminum nanofibers has prompted us to study their role in their mechanical and tribological properties. Materials and Methods Research In this work we used ultra high molecular weight polyethylene grades GUR4120UHMW-PE produced by company Ticona (Germany): molecular weight 3.10 3 kg/mol, the density about 930 kg/m 3 . Copolymers of ultra high molecular weight polyethylene with monomer styrene maleic anhydride (UHMWPE-g-SMA) were obtained by solid state reaction, using a planetary mill in an atmosphere of ozone (GC "Olenty", Moscow). Introduction of monomer styrene in the copolymer is allowed to increase the degree of graſting of maleic anhydride to polyethylene, which is made up. Mechanical mixing of the binder (GUR4120UHMWPE), a copolymer (UHMWPE-g-SMA), a different percentage (in the range 1-20%) and filler (nanofibers Al 2 O 3 ) was performed in a planetary ball mill. Samples were prepared by hot pressing at the following mode: a pressure of 10 MPa and a temperature of 190°C and a cooling rate of 3÷4ºC /min. Mechanical characteristics of the composites under static loading were measured on a tensile testing machine INSTRON-5582. e samples were tensile-shaped double blades with sizes 250×5×0.9 mm, stretched at a constant speed, recording recording applied load and elongation. Shore hardness was determined using a universal instrument FLASH-1R. Tests on the "dry" friction performed on a "roller-shoe". e sample size was 8×8×10 mm, diameter 62 mm rider, *Corresponding author: Chuong Nguyen V, Don State Technical University, Rostov, Russia, E-mail: [email protected] Received October 14, 2012; Published December 03, 2012 Citation: Ilyasov V, Nguyen VC, Ershov I (2012) Modification Effects of Nanofibers Al 2 O 3 and Copolymer Styrene Maleic Anhydride on Ultra High Molecur Weight Polyethylene in the Mechanical and Tribological Properties. 1:561 doi:10.4172/ scientificreports.561 Copyright: © 2012 Ilyasov V. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Abstract The results of tests of mechanical and tribological properties of composite materials based on Ultra High Molecular Weight Polyethylene, a chemically modified and maleic anhydride, depending on the content and filler components such as aluminium oxide nanofibers. Modification Effects of Nanofibers Al 2 O 3 and Copolymer Styrene Maleic Anhydride on Ultra High Molecur Weight Polyethylene in the Mechanical and Tribological Properties Victor Ilyasov, Chuong Nguyen V* and Igor Ershov Don State Technical University, Rostov, Russia the speed is 100 rev/min, the load was160 N. e surface friction of the samples studied in the optical profilometer. e area of the friction track was determined using the soſtware (Rhinoceros 4.0) by manual selection of the contour surface abrasion and subsequent automatic calculation of the area. Evaluation of thickness of the layer blown conducted the installation of optical images taken at the surface friction, by recalculating its value through a measured value of the friction track width by the formula 2 2 4 x R R l = − − . Here, R - radius of the shaſt, l-friction track width on the sample. Wear rate was determined as the slope of the tangent to the curve corresponding to the steady deterioration of the stage of the formula tg U t α =∆ ∆ . Here U ∆ is the difference between the area at the end and beginning of the stage of sustainable wear t ∆ - wear time. Wear resistance was determined as the reciprocal of wear rate. e path traversed in each time interval was calculated by the formula: 1 S l t ω = ⋅ ⋅ where ω is the speed of rotation of the shaſt, l1 is length of the circle, is the time of wear. Results and Discussion In the first phase investigated the mechanical properties of the compositions ultra high molecular weight of polyethylene copolymer with different contents such as x% UHMWPE-g-SMA (x=1÷20%) and 0.5 % of filler such as aluminum oxide nanofibers, introduced in the starting powder mixture. Table 1 shows the mechanical properties of UHMWPE composition of the original, modified filler composition: UHMWPE+0.5% Al 2 O 3 , UHMWPE compositions for the different content of the copolymer and a fixed filler content (0.5% nanofibers Al 2 O 3 ). Analysis the data in table 1 reveals the following pattern: the first, that when added to the composition of aluminum oxide nanofibers elastic properties of the compositions varies insignificantly, and secondly, with the increasing content of the copolymer of maleic anhydride only in the elastic modulus of UHMWPE composition slightly decreases. Elastic-plastic
Transcript of Ilyasov, et al., 1:12 Open Access Scientific Reportsof mechanical activation of...
-
Open Access
Ilyasov, et al., 1:12http://dx.doi.org/10.4172/scientificreports.561
Research Article Open Access
Open Access Scientific ReportsScientific Reports
Open Access
Volume 1 • Issue 12 • 2012
Keywords: Ultra high molecular weight polyethylene; Styrene; Maleic anhydride; Nanofiller; Aluminium oxide; Wear resistance; Mechanical properties
IntroductionIn recent years, considerable interest are composites based on ultra-
high molecular weight polyethylene (UHMWPE) [1,2]. The formation of the functional properties of the composites is significantly affected by the modification of nanofibers and nanoparticles UHMWPE at low concentrations (0.1-0.5%) [3]. It is known that the modification of polymers are widely used graft copolymers [4], mixing them with other components of the mixture (in the case of the reaction) leads to an improvement of interfacial interaction [5]. Chemical modification of UHMWPE significantly increases its wear resistance, due to peculiarities of crystallization and the formation of the supramolecular structure of the polymer [1].
The incompleteness of the data on the peculiarities of formation of the functional properties of the polymer-polymer composites based on UHMWPE, while the influence of the different contents of grafted UHMWPE and fillers in the form of oxide aluminum nanofibers has prompted us to study their role in their mechanical and tribological properties.
Materials and Methods ResearchIn this work we used ultra high molecular weight polyethylene
grades GUR4120UHMW-PE produced by company Ticona (Germany): molecular weight 3.103 kg/mol, the density about 930 kg/m3. Copolymers of ultra high molecular weight polyethylene with monomer styrene maleic anhydride (UHMWPE-g-SMA) were obtained by solid state reaction, using a planetary mill in an atmosphere of ozone (GC "Olenty", Moscow). Introduction of monomer styrene in the copolymer is allowed to increase the degree of grafting of maleic anhydride to polyethylene, which is made up. Mechanical mixing of the binder (GUR4120UHMWPE), a copolymer (UHMWPE-g-SMA), a different percentage (in the range 1-20%) and filler (nanofibers Al2O3) was performed in a planetary ball mill. Samples were prepared by hot pressing at the following mode: a pressure of 10 MPa and a temperature of 190°C and a cooling rate of 3÷4ºC /min.
Mechanical characteristics of the composites under static loading were measured on a tensile testing machine INSTRON-5582. The samples were tensile-shaped double blades with sizes 250×5×0.9 mm, stretched at a constant speed, recording recording applied load and elongation. Shore hardness was determined using a universal instrument FLASH-1R. Tests on the "dry" friction performed on a "roller-shoe". The sample size was 8×8×10 mm, diameter 62 mm rider,
*Corresponding author: Chuong Nguyen V, Don State Technical University, Rostov, Russia, E-mail: [email protected]
Received October 14, 2012; Published December 03, 2012
Citation: Ilyasov V, Nguyen VC, Ershov I (2012) Modification Effects of Nanofibers Al2O3 and Copolymer Styrene Maleic Anhydride on Ultra High Molecur Weight Polyethylene in the Mechanical and Tribological Properties. 1:561 doi:10.4172/scientificreports.561
Copyright: © 2012 Ilyasov V. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
AbstractThe results of tests of mechanical and tribological properties of composite materials based on Ultra High
Molecular Weight Polyethylene, a chemically modified and maleic anhydride, depending on the content and filler components such as aluminium oxide nanofibers.
Modification Effects of Nanofibers Al2O3 and Copolymer Styrene Maleic Anhydride on Ultra High Molecur Weight Polyethylene in the Mechanical and Tribological PropertiesVictor Ilyasov, Chuong Nguyen V* and Igor ErshovDon State Technical University, Rostov, Russia
the speed is 100 rev/min, the load was160 N. The surface friction of the samples studied in the optical profilometer. The area of the friction track was determined using the software (Rhinoceros 4.0) by manual selection of the contour surface abrasion and subsequent automatic calculation of the area.
Evaluation of thickness of the layer blown conducted the installation of optical images taken at the surface friction, by recalculating its value through a measured value of the friction track width by the formula
2 2 4x R R l= − − . Here, R - radius of the shaft, l-friction track width on the sample. Wear rate was determined as the slope of the tangent to the curve corresponding to the steady deterioration of the stage of the formula tg U tα = ∆ ∆ . Here U∆ is the difference between the area at the end and beginning of the stage of sustainable wear t∆ - wear time. Wear resistance was determined as the reciprocal of wear rate. The path traversed in each time interval was calculated by the formula: 1S l tω= ⋅ ⋅where ω is the speed of rotation of the shaft, l1 is length of the circle, is the time of wear.
Results and DiscussionIn the first phase investigated the mechanical properties of the
compositions ultra high molecular weight of polyethylene copolymer with different contents such as x% UHMWPE-g-SMA (x=1÷20%) and 0.5 % of filler such as aluminum oxide nanofibers, introduced in the starting powder mixture.
Table 1 shows the mechanical properties of UHMWPE composition of the original, modified filler composition: UHMWPE+0.5% Al2O3, UHMWPE compositions for the different content of the copolymer and a fixed filler content (0.5% nanofibers Al2O3). Analysis the data in table 1 reveals the following pattern: the first, that when added to the composition of aluminum oxide nanofibers elastic properties of the compositions varies insignificantly, and secondly, with the increasing content of the copolymer of maleic anhydride only in the elastic modulus of UHMWPE composition slightly decreases. Elastic-plastic
http://dx.doi.org/10.4172/scientificreports.300http://dx.doi.org/10.4172/scientificreports.300
-
Citation: Ilyasov V, Nguyen VC, Ershov I (2012) Modification Effects of Nanofibers Al2O3 and Copolymer Styrene Maleic Anhydride on Ultra High Molecur Weight Polyethylene in the Mechanical and Tribological Properties. 1:561 doi:10.4172/scientificreports.561
Page 2 of 2
Volume 1 • Issue 12 • 2012
UHMWPE-gSMA and filler in the UHMWPE decreased by 1,4 and 2,6 times respectively. The best antifriction properties observed in UHMWPE is chemically modified with 10 % UHMWPE-gSMA and 0.5 % nanofibers aluminum oxide. The diagrams wear intensity of the content of the modifiers studied here (UHMWPE+x% UH-gSMA+0.5% Al2O3) are shown in figure 2.
A generalization of the results allowed to determine, firstly, that the use of filler (nanofibers Al2O3) significantly reduces the wear intensity of the composite based on UHMWPE, second, expanding the optimal region of the chemical modification of the monomers. At the stage of steady-state wear durability of UHMWPE increases in both cases. In particular, the addition of 0.5% nanofibers Al2O3 and 10 % chemically modified UHMWPE, wear it grows to a greater extent (4.5 times) than in the case of adding only 10% chemically modified UHMWPE (2.3 times relative unmodified UHMWPE).
Conclusion Thus, the work shows the possibility of controlling the tribological
properties of composite polymer materials based on modified UHMW polyethylene. It is established that the use as a filler, a minor amount of nanofibers aluminum oxide (0.5%) Significantly reduces the wear intensity of the composite on the basis of UHMWPE+x% UHMWPE-g-SMA+0.5% Al2O3. In the presence of 0.5% nanofibers aluminum oxide observed optimal expansion of the content of the copolymer (5÷10)% UHMWPE-g-SMA, which reduces to twice the content of the copolymer. The latter, besides saving time and material, in our view, should lead to a decrease in degradation of UHMW polyethylene, and modified the quality of products.References1. Panin VE, Panin SV, Kornienko LA, Vannasri S, Ivanova LR, et al. (2010) Effect
of mechanical activation of ultra-high-molecular-weight polyethylene on its mechanical and triboengineering properties. Journal of Friction and Wear 31: 121-127.
2. Donald PR, Clive BB (2000) Polymer Blends Formulation and Performance. John Wiley & Sons USA.
3. Askeland DR, Fulay PP, Wright WJ (2010) The Science and Engineering of Materials. Cengage Learning India.
4. Malkin, Vinogradov (1980) Rheology Of Polymers: Viscoelasticity And Flow Of Polymers. Springer-Verlag Berlifn, Germany.
5. Prut EV, Zelenetsky AN (2001) Chemical modification and blending of polymers in the extruder-reactor. Advances Chemical 70: 72-87.
characteristics of UHMWPE, such as tensile strength and elongation at break, change significantly during the filling of the composition of aluminum oxide nanofibers and modifying copolymer. We determined the wear resistance of composite materials described above. Time dependence of the friction area of the track tracks UHMWPE is shown in figure 1.
Analysis figure 1 show that the growth area of the friction track during the test is significantly reduced by adding both chemical modifiers (styrene maleic anhydride) and a filler - nanofibers aluminum oxide. The best result was obtained in the samples contained 10% styrene maleic anhydride doped UHMWPE and 0.5% nanofibers aluminum oxide Al2O3 (Figure 1, curve 5).
The dependences of the thickness of the layer blown and the wear intensity of friction for the original UHMWPE and UHMWPE, chemically modified UHMWPE-gSMA and 0.5 wt.% Aluminum oxide nanofibers. It is shown that the anti-friction properties of UHMWPE increase significantly, while adding the modifier and the filler. The thickness of the blown layer and the wear intensity with increasing
Materials Density g/cm3Shore
hardress
Elastic module
MPa
Yeild strength
MPa
Ultimate strength
MPa
Elonga-tion at
break %
UHMWPE 0.916 97.9 549.5 20.0 34.3 470.9UHMWPE+ 1%UHMWPE-gSMA+0.5% A Al2O3
0.921 98.2 590.0 17.6 27.9 382.0
UHMWPE+ 3%UHMWPE-gSMA+0.5% Al2O3
0.920 98.4 582.6 18.3 32.2 457.0
UHMWPE+ 5%UHMWPE-gSMA+0.5% Al2O3
0.922 98.3 576.3 17.3 32.2 476.7
UHMWPE+ 10%UHMWPE-gSMA+0.5% Al2O3
0.22 98.4 572.1 18.1 32.3 475.5
UHMWPE+ 20%UHMWPE- gSMA+0.5% Al2O3
0.924 98.3 564.7 16.8 34.3 479.2
Table 1: Mechanical characheristics of composmaterial UHMWPE.
10 60 110 160
40
30
20
10
0Time (min)
curve line 1
curve line 2
curve line 3
curve line 4
curve line 5
curve line 6
Wear track area (mm2)
Figure 1: The dependence wear track area at time for UHMWPE compositions (filled with 0.5% Al2O3) content of the copolymer x% UHMWPE-g-SMA: 1- 0%, 2 – 1%, 3 – 3%, 4 – 5%, 5 – 10%, 6 – 20%.
10
8
6
4
2
01 2 3 4 5
Wear intensity . 10-10 M2/C
UHMWPEUHMWPE+ x%UHMWPE-gSMAUHMWPE+ x%UHMWPE-gSMA + 0,5%Al2O3
Figure 2: The dependence wear intensity from composition of the composite 1, 2, 3, 4, 5 in accordance with the content of 1%, 3%, 5%, 10%, 20% UHMWPE-g-SMA.
http://dx.doi.org/10.4172/scientificreports.300http://link.springer.com/article/10.3103%2FS1068366610020054?LI=truehttp://books.google.co.in/books/about/The_Science_and_Engineering_of_Materials.html?id=qzqmvFEhWcoChttp://www.angusrobertson.com.au/book/rheology-of-polymers-viscoelasticity-and-flow-of-polymers/6989605/
TitleCorresponding authorAbstractKeywordsIntroductionMaterials and Methods ResearchResults and DiscussionConclusionTable 1Figure 1Figure 2References
