, Volume 21, Issue 6, pp 4231–4246 | Cite as

Thermally-activated shape memory behaviour of bionanocomposites reinforced with cellulose nanocrystals

Original Paper


Bionanocomposites with thermally-activated shape memory ability have been designed based on a synthesized poly(ester-urethane) matrix reinforced with both neat and functionalized cellulose nanocrystals. The functionalization of the cellulose nanocrystals was performed by grafting poly(l-lactic acid) (PLLA) chains onto their surface. The matrix has a block copolymer structure of two biodegradable and biocompatible polymers, poly(ε-caprolactone) (PCL) and PLLA. This research is focused on the effects of cellulose nanofillers on the thermally-activated shape memory response of the neat matrix confirming that the bionanocomposites are able to show shape memory effects at 35 °C, close to the human body temperature, making these materials good candidates for biomedical applications. Three thermo-mechanical cycles at 50 % of deformation were performed in order to check the thermally-activated shape memory ability of the bionanocomposites and to determine the shape memory parameters, namely the strain fixity (Rf), and the strain recovery (Rr) ratio. Both bionanocomposites, with neat and functionalized cellulose nanocrystals, present excellent shape memory behaviour maintaining the recovery behaviour at values of about 90 % as measured previously for the pure matrix, indicating that the addition of the nanofiller maintains the good ability to recover the initial shape of the matrix. The cellulose nanofillers clearly improve the ability of the polymer to fix the temporary shape. In fact, the bionanocomposites show Rf at about 90 %. Moreover, bionanocomposites reinforced with the functionalized cellulose nanocrystals maintain constant their performance during all the thermo-mechanical cycles thus confirming that the improvement in the shape memory behaviour can be mainly attributed to the increase of the interactions between the functionalized cellulose nanocrystals with the polymeric matrix.


Poly(l-lactic acid) Poly(ε-caprolactone) Bionanocomposites Thermally-activated shape memory behaviour Cellulose nanocrystals 



We are indebted to the Spanish Ministry of Economy and Competitiveness (MINECO) for their economic support of this research (MAT2013-48059-C2-1-R). LP acknowledges also, the support of a JAEdoc Grant from CSIC cofinanced by FSE. We thank the technical support of Marco Rallini and Franco Dominici from the STM group of the University of Perugia for SEM photographs and microextruder blending, respectively.


  1. Ahmad M, Luo J, Xu B, Purnawali H, King PJ, Chalker PR, Fu Y, Huang W, Miraftab M (2011) Synthesis and characterization of polyurethane-based shape-memory polymers for tailored T-g around body temperature for medical applications. Macromol Chem Phys 212(6):592–602CrossRefGoogle Scholar
  2. Auad ML, Contos VS, Nutt S, Aranguren MI, Marcovich NE (2008) Characterization of nanocellulose-reinforced shape memory polyurethanes. Polym Int 57(4):651–659CrossRefGoogle Scholar
  3. Bates FS, Fredrickson GH (1999) Block copolymers: designer soft materials. Phys Today 52(2):32–38CrossRefGoogle Scholar
  4. Behl M, Ridder U, Feng Y, Kelch S, Lendlein A (2009) Shape-memory capability of binary multiblock copolymer blends with hard and switching domains provided by different components. Soft Matter 5(3):676–684CrossRefGoogle Scholar
  5. Behl M, Razzaq MY, Lendlein A (2010) Multifunctional shape-memory polymers. Adv Mater 22(31):3388–3410CrossRefGoogle Scholar
  6. Behl M, Zotzmann J, Lendlein A (2011) One-way and reversible dual-shape effect of polymer networks based on polypentadecalactone segments. Int J Artif Organs 34(2):231–237CrossRefGoogle Scholar
  7. Bitinis N, Verdejo R, Bras J, Fortunati E, Kenny JM, Torre L, López-Manchado MA (2013) Poly(lactic acid)/natural rubber/cellulose nanocrystal bionanocomposites Part I. Processing and morphology. Carbohydr Polym 96(2):611–620CrossRefGoogle Scholar
  8. Carlmark A, Larsson E, Malmström E (2012) Grafting of cellulose by ring-opening polymerisation: a review. Eur Polym J 48(10):1646–1659CrossRefGoogle Scholar
  9. Chen Q, Liang S, Thouas GA (2013) Elastomeric biomaterials for tissue engineering. Prog Polym Sci 38(3–4):584–671CrossRefGoogle Scholar
  10. Cranston ED, Gray DG (2006) Morphological and optical characterization of polyelectrolyte multilayers incorporating nanocrystalline cellulose. Biomacromolecules 7(9):2522–2530CrossRefGoogle Scholar
  11. Fortunati E, Armentano I, Zhou Q, Iannoni A, Saino E, Visai L, Berglund LA, Kenny JM (2012) Multifunctional bionanocomposite films of poly(lactic acid), cellulose nanocrystals and silver nanoparticles. Carbohydr Polym 87(2):1596–1605CrossRefGoogle Scholar
  12. Fortunati E, Puglia D, Monti M, Santulli C, Maniruzzaman M, Kenny JM (2013) Cellulose nanocrystals extracted from okra fibers in PVA nanocomposites. J Appl Polym Sci 128(5):3220–3230CrossRefGoogle Scholar
  13. Goffin A-L, Raquez J-M, Duquesne E, Siqueira G, Habibi Y, Dufresne A, Dubois P (2011) From interfacial ring-opening polymerization to melt processing of cellulose nanowhisker-filled polylactide-based nanocomposites. Biomacromolecules 12(7):2456–2465CrossRefGoogle Scholar
  14. Guo B, Chen Y, Lei Y, Zhang L, Zhou WY, Rabie ABM, Zhao J (2011) Biobased poly(propylene sebacate) as shape memory polymer with tunable switching temperature for potential biomedical applications. Biomacromolecules 12(4):1312–1321CrossRefGoogle Scholar
  15. Han J, Zhu Y, Hu J, Luo H, Yeung L-Y, Li W, Meng Q, Ye G, Zhang S, Fan Y (2012) Morphology, reversible phase crystallization, and thermal sensitive shape memory effect of cellulose whisker/SMPU nano-composites. J Appl Polym Sci 123(2):749–762CrossRefGoogle Scholar
  16. Huang WM, Zhao Y, Wang CC, Ding Z, Purnawali H, Tang C, Zhang JL (2012) Thermo/chemo-responsive shape memory effect in polymers: a sketch of working mechanisms, fundamentals and optimization. J Polym Res 19(9):1–34 Google Scholar
  17. Knight PT, Lee KM, Qin H, Mather PT (2008) Biodegradable thermoplastic polyurethanes incorporating polyhedral oligosilsesquioxane. Biomacromolecules 9(9):2458–2467CrossRefGoogle Scholar
  18. Lendlein A, Kelch S (2002) Shape-memory polymers. Angewandte Chemie (Int ed Eng) 41(12):2035–2057Google Scholar
  19. Lendlein A, Langer R (2002) Biodegradable, elastic shape-memory polymers for potential biomedical applications. Science 296(5573):1673–1676CrossRefGoogle Scholar
  20. Lendlein A, Jiang HY, Junger O, Langer R (2005) Light-induced shape-memory polymers. Nature 434(7035):879–882CrossRefGoogle Scholar
  21. Li J, Rodgers WR, Xie T (2011) Semi-crystalline two-way shape memory elastomer. Polymer 52(23):5320–5325CrossRefGoogle Scholar
  22. Lin N, Chen G, Huang J, Dufresne A, Chang PR (2009) Effects of polymer-grafted natural nanocrystals on the structure and mechanical properties of poly(lactic acid): a case of cellulose whisker-graft-polycaprolactone. J Appl Polym Sci 113(5):3417–3425CrossRefGoogle Scholar
  23. Liu LL, Cai W (2009) Novel copolyester for a shape-memory biodegradable material in vivo. Mater Lett 63(20):1656–1658CrossRefGoogle Scholar
  24. Lönnberg H, Fogelström L, Berglund L, Malmström E, Hult A (2008) Surface grafting of microfibrillated cellulose with poly(ε-caprolactone): synthesis and characterization. Eur Polymer J 44(9):2991–2997CrossRefGoogle Scholar
  25. Lu Q, Tang L, Lin F, Wang Q, Chen Y, Chen X, Huang B (2014) Preparation and characterization of cellulose nanocrystals via ultrasonication-assisted FeCl3-catalyzed hydrolysis. Cellulose. doi: 10.1007/s10570-014-0376-2
  26. Navarro-Baena I, Marcos-Fernandez A, Fernandez-Torres A, Kenny JM, Peponi L (2014a) Synthesis of PLLA-b–PCL-b–PLLA linear tri-block copolymers and their corresponding poly(ester-urethane)s: effect of the molecular weight on their crystallisation and mechanical properties. RSC Adv 4(17):8510–8524CrossRefGoogle Scholar
  27. Navarro-Baena I, Kenny JM, Peponi L (2014b) Crystallization and thermal characterization of biodegradable tri-block copolymers and poly(ester-urethane)s based on PCL and PLLA. Polym Degrad Stab. doi: 10.1016/j.polymdegradstab.2014.03.012 Google Scholar
  28. Özgür Seydibeyoǧlu M, Oksman K (2008) Novel nanocomposites based on polyurethane and micro fibrillated cellulose. Compos Sci Technol 68(3–4):908–914CrossRefGoogle Scholar
  29. Park C, De Rosa C, Thomas EL (2001) Large area orientation of block copolymer microdomains in thin films via directional crystallization of a solvent. Macromolecules 34(8):2602–2606CrossRefGoogle Scholar
  30. Peng Y, Gardner DJ, Han Y, Kiziltas A, Cai Z, Tshabalala MA (2013) Influence of drying method on the material properties of nanocellulose I: thermostability and crystallinity. Cellulose 20(5):2379–2392CrossRefGoogle Scholar
  31. Peponi L, Navarro-Baena I, Baez JE, Kenny JM, Marcos-Fernandez A (2012) Effect of the molecular weight on the crystallinity of PCL-b–PLLA di-block copolymers. Polymer 53(21):4561–4568CrossRefGoogle Scholar
  32. Peponi L, Navarro-Baena I, Sonseca A, Gimenez E, Marcos-Fernandez A, Kenny JM (2013) Synthesis and characterization of PCL-PLLA polyurethane with shape memory behavior. Eur Polym J 49(4):893–903CrossRefGoogle Scholar
  33. Peponi L, Navarro-Baena I, Kenny JM (2014) Shape memory polymers: properties, synthesis and applications. In: Aguilar MR, San Román J (eds) Smart polymers and their applications. Woodhead Publishing, Cambridge, pp 204–236Google Scholar
  34. Raquez J-M, Vanderstappen S, Meyer F, Verge P, Alexandre M, Thomassin J-M, Jerome C, Dubois P (2011) Design of cross-linked semicrystalline poly(epsilon-caprolactone)-based networks with one-way and two-way shape-memory properties through diels–alder reactions. Chem Eur J 17(36):10135–10143CrossRefGoogle Scholar
  35. Ruan C, Wang Y, Zhang M, Luo Y, Fu C, Huang M, Sun J, Hu C (2012) Design, synthesis and characterization of novel biodegradable shape memory polymers based on poly(D, L-lactic acid) diol, hexamethylene diisocyanate and piperazine. Polym Int 61(4):524–530CrossRefGoogle Scholar
  36. Rueda L, Saralegui A, Fernández d’Arlas B, Zhou Q, Alonso-Varona A, Berglund LA, Mondragon I, Corcuera MA, Eceiza A (2013a) In situ polymerization and characterization of elastomeric polyurethane-cellulose nanocrystal nanocomposite. Cell response evaluation. Cellulose 20(4):1819–1828CrossRefGoogle Scholar
  37. Rueda L, Saralegui A, Fernández d’Arlas B, Zhou Q, Berglund LA, Corcuera MA, Mondragon I, Eceiza A (2013b) Cellulose nanocrystals/polyurethane nanocomposites. Study from the viewpoint of microphase separated structure. Carbohydr Polym 92(1):751–757CrossRefGoogle Scholar
  38. Saralegi A, Fernandes CM, Alonso-Varona A, Palomares T, Foster EJ, Weder C, Eceiza A, Corcuera MA (2013) Shape-memory bionanocomposites based on chitin nanocrystals and thermoplastic polyurethane with a highly crystalline soft segment. Biomacromolecules 14(12):4475–4482CrossRefGoogle Scholar
  39. Saralegi A, Gonzalez ML, Valea A, Eceiza A, Corcuera MA (2014) The role of cellulose nanocrystals in the improvement of the shape-memory properties of castor oil-based segmented thermoplastic polyurethanes. Compos Sci Technol 92:27–33CrossRefGoogle Scholar
  40. Segal L, Creely JJ, Martin AE Jr, Conrad CM (1959) An empirical method for estimating the degree of crystallinity of native cellulose using the X-ray diffractometer. Text Res J 29(10):202–209CrossRefGoogle Scholar
  41. Siqueira G, Bras J, Dufresne A (2010) Cellulosic bionanocomposites: a review of preparation, properties and applications. Polymers 2(4):728–765CrossRefGoogle Scholar
  42. Van Minnen B, Van Leeuwen MBM, Stegenga B, Zuidema J, Hissink CE, Van Kooten TG, Bos RRM (2005) Short-term in vitro and in vivo biocompatibility of a biodegradable polyurethane foam based on 1,4-butanediisocyanate. J Mater Sci Mater Med 16(3):221–227CrossRefGoogle Scholar
  43. Wang CC, Huang WM, Ding Z, Zhao Y, Purnawali H (2012) Cooling-/water-responsive shape memory hybrids. Compos Sci Technol 72(10):1178–1182CrossRefGoogle Scholar
  44. Zhang C, Zhang N, Wen X (2006) Improving the elasticity and cytophilicity of biodegradable polyurethane by changing chain extender. J Biomed Mater Res B Appl Biomater 79B(2):335–344CrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media Dordrecht 2014

Authors and Affiliations

  1. 1.Department of Civil and Environmental EngineeringUniversity of PerugiaTerniItaly
  2. 2.Instituto de Ciencia y Tecnología de Polímeros, ICTP-CSICMadridSpain

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