Enhanced tensile performance of epoxy and E-glass/epoxy composites by randomly-oriented amino-functionalized MWCNTs at low contents

Abstract

Effect of amino-functionalized multi-walled carbon nanotubes (NH₂-MWCNTs) on the tensile performance of epoxy and E-glass/epoxy composites was investigated. Low weight percentages (0.3 and 0.4 wt%) of NH₂-MWCNTs were dispersed into a DGEBA epoxy resin using combination of sonication and three-roll milling methods. Composites with plain weave E-glass fabrics were fabricated by compression molding process. Tensile test results showed a significant enhancement in strength, modulus and toughness of epoxy and E-glass/epoxy composites at 0.3 wt% loading of NH₂-MWCNTs. Micrographs of NH₂-MWCNTs-incorporated epoxy and E-glass/epoxy composites revealed better dispersion of nanotubes in epoxy, better bonding between nanotubes and polymer and improved interfacial adhesion between fiber/matrix at 0.3 wt% loading. Micromechanical models were used to predict the tensile properties and compared with the experimental results. An improved dispersion and hence an enhanced crosslink interaction between NH₂-MWCNTs and epoxy lead to the improvements in the tensile properties of the epoxy nanocomposites close to predicted values at 0.3 wt% loading. A similar rationale applies for the increase in properties of E-glass/epoxy nanocomposites.

Keywords

Mechanical properties nanostructures polymer-matrix composites analytical modeling

Get full access to this article

View all access options for this article.

References

Gojny

Wichmann

MHG

Fiedler

. Influence of nano modification on the mechanical and electrical properties of conventional fibre-reinforced composites. Compos Pt A: Appl Sci Manuf 2005; 36: 1525–1535.

Rahman

Zainuddin

Hosur

. Improvements in mechanical and thermo-mechanical properties of e-glass/epoxy composites using amino-functionalized multi-walled carbon nanotubes. Compos Struct 2012; 94: 2397–2406.

Beyakrova

Thostenson

. Multiscale carbon nanotube-carbon fiber reinforcement for advanced epoxy composites. Langmuir 2007; 23: 3970–3974.

Yeh

Hsieh

T-H

Tai

N-H

. Fabrication and mechanical properties of multi-walled carbon nanotubes/epoxy nanocomposites. Mater Sci Eng A 2008; 483–484: 289–292.

Iijima

Ichihashi

. Single shell carbon nanotubes of 1 nm diameter. Nature 1993; 363: 603–605.

Guo

Chen

Gao

. Fabrication and mechanical properties of well-dispersed multiwalled carbon nanotubes/epoxy composites. Compos Sci Technol 2007; 67: 3331–3337.

Siddiqui

Sham

. Tensile strength of glass fibres with carbon nanotube-epoxy nanocomposite coating: effects of CNTs morphology and dispersion state. Compos Pt A: Appl Sci Manuf 2010; 41: 539–548.

Davis

Wilkerson

Zhu

. A strategy for improving mechanical properties of a fiber reinforced epoxy composite using functionalized carbon nanotubes. Compos Sci Technol 2011; 71: 1089–1097.

Gojny

Wichmann

Fiedler

. Influence of different carbon nanotubes on the mechanical properties of epoxy matrix composites – a comparative study. Compos Sci Technol 2005; 65: 2300–2313.

10.

Song

Youn

. Influence of dispersion sates of carbon nanotubes on physical properties of epoxy nanocomposites. Carbon 2005; 43: 1378–1385.

11.

Tang

. Dispersion, interfacial interaction and reagglomeration of functionalized carbon nanotubes in epoxy composites. Carbon 2010; 48: 1824–1834.

12.

Allaoui

Bai

Cheng

. Mechanical and electrical properties of a MWNT/epoxy composite. Compos Sci Technol 2003; 62: 1993–1998.

13.

Lago

Chen

. Mechanical damage of carbon nanotubes by ultrasound. Carbon 1996; 34: 814–816.

14.

Mukhopadhyay

Dwivedi

Mathur

. Conversion of carbon nanotubes to carbon nanofibers by sonication. Carbon 2002; 40: 1373–1376.

15.

Siddiqui

Marom

. Dispersion and functionalization of carbon nanotubes for polymer-based nanocomposites: a review. Compos Pt A: Appl Sci Manuf 2010; 41: 1345–1367.

16.

Bai

Allaoui

. Effect of the length and aggregate size of MWNTs on the mechanical and electrical properties of the nanocomposites. Compos Pt A 2003; 34: 689–694.

17.

Wang

Fang

. Effect of amino-functionalization of multi-walled carbon nanotubes on the dispersion with epoxy resin matrix. J Appl Polym Sci 2006; 100: 97–104.

18.

Park

Bae

Seo

. A study on rheological behavior of MWCNTs/epoxy composites. J Ind Eng Chem 2010; 16: 337–339.

19.

Montazeri

Khavandi

Javadpour

. Viscoelastic properties of multi-walled carbon nanotube/epoxy composites using two different curing cycles. Mater Design 2010; 31: 3383–3388.

20.

Annual Book of ASTM Standards, D 638-02, Standard Test Method for Tensile Properties of Plastics, 2002.

21.

Annual Book of ASTM Standards, D 3039 M-08, Standard Test Method for Tensile Properties of Polymer Matrix Composite Materials, 2008.

22.

Thostenson

Chou

. On the elastic properties of carbon nanotube-based composites: modelling and characterization. J Phys D: Appl Phys 2003; 36: 573–582.

23.

Wang

Gong

Liu

. Influence of physical aging and side group on the free volume of epoxy resins probed by positron. Polymer 2003; 44: 4047–4052.

24.

Shen

Huang

. Thermo-physical properties of epoxy nanocomposites reinforced with amino-functionalized multi-walled carbon nanotubes. Compos Pt A 2007; 38: 1331–1336.

25.

Halpin JC and Tsai SW. Air force material laboratory technical report, AFML-TR-67-423, 1967.

26.

Cox

. The elasticity and strength of paper and other fibrous materials. Brit J Appl Phys 1952; 3: 72–79.

27.

Krenchel

. Fiber reinforcement, Copenhagen: Akademisk Forlag, 1964.

28.

Fisher

Bradshaw

Brinson

. Fiber waviness in nanotube-reinforced polymer composites-I: modulus predictions using effective nanotube properties. Compos Sci Tech 2003; 63: 1689–1703.

29.

Rio

Poza

Rodriguez . Influence of single-walled carbon nanotubes on the effective elastic constants of poly(ethylene terephthalate). Compos Sci Tech 2010; 70: 284–290.

30.

Belingardi

Paolino

Koricho

. Investigation of influence of tab types on tensile strength of E-glass/epoxy fiber reinforced composite materials. Procedia Engg 2011; 10: 3279–3284.