Abstract
The replacement of synthetic foams with agglomerated cork in sandwich composites can meet the increasing environmental concerns. Its peculiar morphology and chemical composition lead to outstanding dimensional recovery that endorsed a broad investigation of its compressive behavior. The knowledge of neat material response is fundamental to obtain a reliable design dataset, but it is necessary to consider all the environmental factors (water, moisture and sunlight) that significantly modify material mechanical properties. In view of this, the present work investigates the effect of distilled and seawater absorption and salt fog exposure on the compressive behavior of two agglomerated corks with different densities to simulate their potential employment in marine environment. The results were suitably compared with the ones of a traditional PVC foam used as benchmark. A dependence of water uptake and diffusivity on cork density and water type was detected. The less dense cork displayed a water uptake between 36.7 and 46.5% higher than the denser cork, and seawater uptake was between 21.8 and 44.4% lower than distilled water one. Concerning the compressive response, water and fog moisture plasticizing effect in wet conditions and a partial healing after drying due to salt crystal deposits were identified. Water plasticizing effect determined a reduction in the compressive modulus between 35.1 and 37.9% for the lighter cork and between 17.7 and 21% for the denser cork whereas fog moisture induced a reduction between 52 and 74% for the lighter cork and between 24 and 76.1% for the denser one.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
Availability of data and material
The raw/processed data required to reproduce these findings cannot be shared at this time as the data also forms part of an ongoing study.
References
Anjos O, Pereira H, Rosa ME (2008) Effect of quality, porosity and density on the compression properties of cork. Holz Roh Werkst 66(4):295–301. https://doi.org/10.1007/s00107-008-0248-2
Anjos O, Rodrigues C, Morais J, Pereira H (2014) Effect of density on the compression behaviour of cork. Mater Des 53:1089–1096. https://doi.org/10.1016/j.matdes.2013.07.038
Arteiro A, Reis ALMA, Novoa PJRO, Silva LFM, Zupan M, Marques AT (2013) Low velocity impact and flexural performance of sandwich structures with cork and polymer foam cores. Ciencia e Tecnologia dos Materiais 25(2):79–84. https://doi.org/10.1016/j.ctmat.2014.03.003
Avalle M, Belingardi G, Montanini R (2001) Characterization of polymeric structural foams under compressive impact loading by means of energy-absorption diagram. Int J Impact Eng 25:455–472. https://doi.org/10.1016/S0734-743X(00)00060-9
Castro O, Silva J, Devezas T, Silva A, Gil L (2010) Cork agglomerates as an ideal core material in lightweight structures. Mater Des 31(1):425–432. https://doi.org/10.1016/j.matdes.2009.05.039
Crouvisier-Urion K, Bellat J-P, Gougeon RD, Karbowiak T (2018) Mechanical properties of agglomerated cork stoppers for sparkling wines: influence of adhesive and cork particle size. Compos Struct 203:789–796. https://doi.org/10.1016/j.compstruct.2018.06.116
Earl JS, Shenoi RA (2004) Determination of the moisture uptake mechanism in closed cell polymeric structural foam during hygrothermal exposure. J Compos Mater 38(15):1345–1365. https://doi.org/10.1177/0021998304042736
Fiore V, Scalici T, Valenza A (2019) Evaluation of aging behavior under salt-fog spray conditions of green sandwich structures. J Nat Fibers 16(7):977–986. https://doi.org/10.1080/15440478.2018.1444530
Gibson LJ, Easterling KE, Ashby MF (1981) The structure and mechanics of cork. Proc R Soc A Math Phys Eng Sci 377(1769):99–117. https://doi.org/10.1098/rspa.1981.0117
Gil L (2009) Cork composites: a review. Materials 2(3):776–789. https://doi.org/10.3390/ma2030776
Hachemane B, Zitoune R, Bezzazi B, Boouvet C (2013) Sandwich composites impact and indentation behaviour study. Compos Part B Eng 51:1–10. https://doi.org/10.1016/j.compositesb.2013.02.014
Hoto R, Furundarena G, Torres JP, Munoz E, Andres J, Garcia JA (2014) Flexural behavior and water absorption of asymmetrical sandwich composites from natural fibers and cork agglomerate core. Mater Lett 127:48–52. https://doi.org/10.1016/j.matlet.2014.04.088
Knapic S, Oliveira V, Machado JS, Pereira H (2016) Cork as a building material: a review. Eur J Wood Prod 74(6):775–791. https://doi.org/10.1007/s00107-016-1076-4
Lagorce-Tachon A, Karbowiak T, Champion D, Gougeon RD, Bellat J-P (2015) Mechanical properties of cork: effect of hydration. Mater Des 82:489–496. https://doi.org/10.1061/9780784480779.060
Mancuso A, Pitarresi G, Tumino D (2015) Mechanical behaviour of a green sandwich made of flax reinforced polymer facings and cork core. Proc Eng 109:144–153. https://doi.org/10.1016/j.proeng.2015.06.225
Manujesh BJ, Vijayalakshmi R, Sham Aan MP (2013) Moisture absorption and mechanical degradation studies of polyurethane foam cored E-glass-reinforced vinyl-ester sandwich composites. J Reinf Plast Compos 33(5):479–492. https://doi.org/10.1177/0731684413503720
May-Pat A, Avilés F (2014) Long term water uptake of a low density polyvinyl chloride foam and its effect on the foam microstructure and mechanical properties. Mater Des 57:728–735. https://doi.org/10.1016/j.matdes.2014.01.042
Najafi M, Darvizeh A, Ansari R (2018) Characterization of moisture effects on novel agglomerated cork core sandwich composites with fiber metal laminate facesheets. J Sandw Struct Mater 0(0):1–34. https://doi.org/10.1177/1099636218789613
Pereira H (2015) The rationale behind cork properties: a review of structure and chemistry. BioResources 10(3):1–23. https://doi.org/10.15376/biores.10.3.Pereira
Reis L, Silva A (2009) Mechanical behavior of sandwich structures using natural cork agglomerates as core materials. J Sandw Struct Mater 11(6):487–500. https://doi.org/10.1177/1099636209104523
Rosa ME, Fortes MA (1988) Rate effects on the compression and recovery of dimensions of cork. J Mater Sci 23(3):879–885. https://doi.org/10.1007/BF01153983
Rosa ME, Fortes MA (1988) Temperature-induced alterations of the structure and mechanical properties of cork. Mater Sci Eng 100:69–78. https://doi.org/10.1016/0025-5416(88)90240-6
Rosa ME, Fortes MA (1989) Effects of water vapour heating on structure and properties of cork. Wood Sci Technol 34:27–34
Rosa ME, Fortes MA (1993) Water absorption by cork. Wood Fiber Sci 25(4):339–348
Rosa ME, Pereira H, Fortes MA (1990) Effects of hot water treatment on the structure and properties of cork. Wood Fiber Sci 22(2):149–164
Scalici T, Fiore V, Valenza A (2018) Experimental assessment of the shield-to-salt-fog properties of basalt and glass fiber reinforced composites in cork core sandwich panels applications. Compos Part B 144:29–36. https://doi.org/10.1016/j.compositesb.2018.02.021
Silva SP, Sabino MA, Fernandes EM, Correlo VM, Boesel LF, Reis RL (2005) Cork: properties, capabilities and applications. Int Mater Rev. https://doi.org/10.1179/174328008X353529
Soares B, Reis L, Silva A (2008) Testing of sandwich structures with cork agglomerate cores. In: Eighth international conference on sandwich structures (ICSS 8), Porto, pp 451–462
Tanganov BB (2013) About sizes of the hydrated salt ions−the components of sea water. Eur J Nat Hist 1:1–2
Tita V, Caliri Junior MF (2012) Numerical simulation of anisotropic polymeric foams. Latin Am J Solids Struct 1:1–21. doi:https://doi.org/10.1590/S1679-78252012000200005
Funding
Part of this work was implemented within the co-creation experiment at Sapienza Università di Roma in the framework of the H2020 project FIT4RRI, G.A. n. 741477. This project received funding from the European Union’s Horizon 2020 research and innovation program under Grant Agreement No. 741477. The APC was funded by the project FIT4RRI.
Author information
Authors and Affiliations
Contributions
CS data curation, formal analysis, investigation, methodology, visualization, writing—original draft. FS methodology, validation, writing—review and editing. VF investigation, methodology, validation, writing—review and editing. EB conceptualization, methodology, supervision, writing—review and editing. SS-S conceptualization, methodology, supervision, writing—review and editing. JT conceptualization, formal analysis, supervision, validation, writing—review and editing.
Corresponding author
Ethics declarations
Conflict of interest
The authors declare no conflicts of interest.
Additional information
Publisher’s Note
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Electronic Supplementary Material
Below is the link to the electronic supplementary material.
Rights and permissions
About this article
Cite this article
Sergi, C., Sarasini, F., Fiore, V. et al. The effects of water absorption and salt fog exposure on agglomerated cork compressive response. Eur. J. Wood Prod. 80, 101–114 (2022). https://doi.org/10.1007/s00107-021-01754-7
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00107-021-01754-7