Cellulose nanoparticles (CNPs) were prepared from microcrystalline cellulose using two concentration levels of sulfuric acid ( i.e., 48 wt% and 64 wt% with produced CNPs designated as CNPs-48 and CNPs-64, respectively) followed by high-pressure homogenization. CNP-reinforced polymethylmethacrylate (PMMA) composite films at various CNP loadings were made using solvent exchange and solution casting methods. The ultraviolet-visible (UV-vis) transmittance spectra between 400 and 800 nm showed that CNPs-64/PMMA composites had a significantly higher optical transmittance than that of CNPs-48/PMMA. Their transmittance decreased with increased CNP loadings. The addition of CNPs to the PMMA matrix reduced composite’s coefficient of thermal expansion (CTE), and CNPs-64/PMMA had a lower CTE than CNPs-48/PMMA at the same CNP level. Reinforcement effect was achieved with the addition of CNPs to the PMMA matrix, especially at higher temperature levels. CNPs-64/PMMA exhibited a higher storage modulus compared with CNPs-48/PMMA material. All CNP-reinforced composites showed higher Young’s modulus and tensile strengths than pure PMMA. The effect increased with increased CNP loadings in the PMMA matrix for both CNPs-64/PMMA and CNPs-48/PMMA composites. CNPs affected the Young’s modulus more than they affected the tensile strength.
References
[1]
French, A.D.; Bertoniere, N.R.; Brown, R.M.; Chanzy, H.; Gray, D.; Hattori, K.; Glasser, W. Cellulose. In Kirk-Othmer Encyclopedia of Chemical Technology; John Wiley & Sons, Inc: New York, NY, USA, 2004; Volume 5, pp. 360–394.
[2]
Heux, L.; Chauve, G.; Bonini, C. Nonflocculating and chiral-nematic self-ordering of cellulose microcrystals suspensions in nonpolar solvents. Langmuir？2000, 16, 8210–8212.
[3]
Brito, B.S.L.; Pereira, F.V.; Putaux, J.-L.; Jean, B. Preparation, morphology and structure of cellulose nanocrystals from bamboo fibers. Cellulose？2012, 19, 1527–1536.
[4]
Iwamoto, S.; Nakagaito, A.N.; Yano, H. Nano-fibrillation of pulp fibers for the processing of transparent nanocomposites. Appl. Phys？2007, 89, 461–466.
[5]
Nishino, T.; Takano, K.; Nakamae, K. Elastic modulus of the crystalline regions of cellulose polymorphs. J. Polym. Sci. B Polym. Phys？1995, 33, 1647–1651.
[6]
Iwamoto, S.; Abe, K.; Yano, H. The effect of hemicelluloses on wood pulp nanofibrillation and nanofiber network characteristics. Biomacromolecules？2008, 9, 1022–1026.
[7]
Moran, J.; Alvarez, V.; Cyras, V.; Vazquez, A. Extraction of cellulose and preparation of nanocellulose from sisal fibers. Cellulose？2008, 15, 149–159.
[8]
Teixeira, E.M.; Correa, A.C.; Manzoli, A.; Leite, F.L.; Oliveira, C.R.; Mattoso, L.H.C. Cellulose nanofibers from white and naturally colored cotton fibers. Cellulose？2010, 17, 595–606.
[9]
Wang, B.; Sain, M.; Oksman, K. Study of structural morphology of hempfiber from the micro to the nanoscale. Appl. Compos. Mater？2007, 14, 89–103.
[10]
Nakagaito, A.N.; Yano, H. Novel high-strength biocomposites based on microfibrillated cellulose having nano-order-unit web-like network structure. Appl. Phys. A？2005, 80, 155–159.
[11]
Suryanegara, L.; Nakagaito, A.N.; Yano, H. The effect of crystallization of PLA on the thermal and mechanical properties of microfibrillated cellulose-reinforced PLA composites. Compos. Sci. Technol？2009, 69, 1187–1192.
[12]
Lu, J.; Askeland, P.; Drzal, L.T. Surface modification of microfibrillated cellulose for epoxy composite applications. Polymer？2008, 49, 1285–1296.
[13]
Yano, H.; Sugiyama, J.; Nakagaito, A.N.; Nogi, M.; Matsuura, T.; Hikita, M.; Handa, K. Optically transparent composites reinforced with networks of bacterial nanofibers. Adv. Mater？2005, 17, 153–155.
[14]
Nakagaito, A.N.; Yano, H. The effect of morphological changes from pulp fiber towards nano-scale fibrillated cellulose on the mechanical properties of high-strength plant fiber based composites. Appl. Phys. A？2004, 78, 547–552.
Nogi, M.; Handa, K.; Nakagaito, A.N.; Yano, H. Optically transparent bionanofiber composites with low sensitivity to refractive index of the polymer matrix. Appl. Phys. Lett？2005, 87, 243110:1–243110:3.
[17]
Nogi, M.; Ifuku, S.; Abe, K.; Handa, K.; Nakagaito, A.N.; Yano, H. Fiber-content dependency of the optical transparency and thermal expansion of bacterial nanofiber reinforced composites. Appl. Phys. Lett？2006, 88, 133124:1–133124:3.
[18]
Ifuku, S.; Nogi, M.; Abe, K.; Handa, K.; Nakatsubo, F.; Yano, H. Surface modification of bacterial cellulose nanofibers for property enhancement of optically transparent composites: Dependence on acetyl-group DS. Biomacromolecules？2007, 8, 1973–1978.
[19]
Nussbaumer, R.J.; Caseri, W.R.; Smith, P.; Tervoort, T. Polymer-TiO2 nanocomposites: A route towards visually transparent broadband UV filters and high refractive index materials. Macromol. Mater. Eng？2003, 288, 44–49.
[20]
Chen, L.S.; Huang, Z.M.; Dong, G.H.; He, C.L.; Liu, L.; Hu, Y.Y.; Li, Y. Development of a transparent PMMA composite reinforced with nanofibers. Polym. Compos？2009, 30, 239–247.
[21]
Liu, H.Y.; Liu, D.G.; Yao, F.; Wu, Q. Fabrication and properties of transparent polymethylmethacrylate/cellulose nanocrystals composites. Bioresour. Technol？2010, 101, 5685–5692.
[22]
Dong, H.; Strawhecker, K.E.; Snyder, J.F.; Orlicki, J.A.; Reiner, R.A.; Rudie, A.W. Cellulose nanocrystals as a reinforcing material for electrospun poly(methyl methacrylate) fibers: Formation, properties and nanomechanical characterization. Carbohydr. Polym？2012, 87, 2488–2495.
[23]
Rasband, W.S.; Image, J. U.S. National Institutes of Health. Available online: http://imagej.nih.gov/ij/ (accessed on 18 December 2013).
[24]
Han, J.; Zhou, C.; Wu, Y.; Liu, F.; Wu, Q. Self-Assembling Behavior of Cellulose Nanoparticles during Freeze-Drying: Effect of Suspension Concentration, Particle Size, Crystal Structure, and Surface Charge. Biomacromolecules？2013, 14, 1529–1540.
Han, J.; Zhou, C.; French, A.D.; Han, G.; Wu, Q. Characterization of cellulose II nanoparticles regenerated from 1-butyl-3-methylimidazolium chloride. Carbohydr. Polym？2013, 94, 773–781.
[27]
Lu, P.; Hsieh, Y.L. Preparation and properties of cellulose nanocrystals: Rods, spheres, and network. Carbohydr. Polym？2010, 82, 329–336.
[28]
Abe, K.; Iwamoto, S.; Yano, H. Obtaining cellulose nanofibers with a uniform width of 15 nm from wood. Biomacromolecules？2007, 8, 3276–3278.
[29]
Bhardwaj, R.; Mohanty, A.K.; Drzal, L.T.; Pourboghrast, F.; Misra, M. Renewable resource-based green composites from recycled cellulose fiber and poly(3-hydroxybutyrate-co-3-hydroxyvalerate) bioplastic. Biomacromolecules？2006, 7(1), 2044–2051.
[30]
Vo, H.T.; Todd, M.; Shi, F.G.; Shapiro, A.A.; Edwards, M. Towards model-based engineering of underfill materials: CTE modeling. Microelectron. J？2001, 32, 331–338.
[31]
Jonoobi, M.; Harun, J.; Mathew, A.P.; Oksman, K. Mechanical properties of cellulose nanofiber (CNF) reinforced polylactic acid (PLA) prepared by twin screw extrusion. Compos. Sci. Technol？2010, 70, 1742–1747.
[32]
Petersoon, L.; Kvien, I.; Oksman, K. Structure and thermal properties of poly(lactic acid)/cellulose whiskers nanocomposite materials. Compos. Sci. Technol？2007, 67, 2535–2544.
[33]
Chen, Z.D.; Li, D.G.; Xu, L.; Wang, Y.M.; Lin, D.L. Research on preparation and properties of cellulose nanofibers and its polymethylmethacrylate (PMMA) based nanocomposites. Appl. Mech. Mater？2012, 174–177, 893–899.
