Experimental study on thermal and morphological analyses of green composite sandwich made of flax and agglomerated cork

  • S. PrabhakaranEmail author
  • V. Krishnaraj
  • Shubham Sharma
  • M. Senthilkumar
  • R. Jegathishkumar
  • R. Zitoune


The building sector has been showing great interest in incorporating technologically advanced materials with lightweight, ecofriendly, high strength, and stiffness properties in flooring, roofing, and partition walls, etc. In addition to the mechanical properties, these materials should have good thermal properties as well. In response to these requirements, an attempt has been made to study the thermal behavior of green composite sandwich made of flax and agglomerated cork. Composite sandwiches were fabricated by using flax as skin reinforcement and agglomerated cork as core with different densities as 240, 280, and 340 kg m−3 using vacuum bagging method. Glass was also used as skin reinforcement for manufacturing composite sandwiches for comparison purpose. Experiments were conducted to predict thermal properties, viz. thermal conductivity, thermal expansion, flammability, and thermal stability. The experimental results show that the lowest thermal conductivity of 0.03 W m−1 K−1 was observed in flax-based composite sandwich having core density of 240 kg m−3; the lowest thermal expansion of 29.2 × 10−5 °C−1 was observed in glass-based composite sandwich having core density of 340 kg m−3; the highest value of time to ignition was 12 s, and minimum propagation rate was 0.25 mm s−1 in flax-based composite sandwich having core density of 340 kg m−3; The highest initial degradation temperature was 362 °C for glass-based skin and 263 °C for cork having density of 240 kg m−3.


Green composite sandwich Flax Agglomerated cork Thermal properties 



The authors do not receive any research fund or grant from any organization.

Compliance with ethical standards

Conflict of interest

The authors declare that they have no conflict of interest with respect to the research, authorship, and/or publication of this article.

Ethical approval

This article does not contain any studies with human participants or animals performed by the author.


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Copyright information

© Akadémiai Kiadó, Budapest, Hungary 2019

Authors and Affiliations

  1. 1.Department of Robotics and Automation EngineeringPSG College of TechnologyCoimbatoreIndia
  2. 2.Department of Production EngineeringPSG College of TechnologyCoimbatoreIndia
  3. 3.Department of Mechanical EngineeringCSIR - Central Leather Research Institute, RCED - JalandharJalandharIndia
  4. 4.Department of Mechanical EngineeringPSG College of TechnologyCoimbatoreIndia
  5. 5.Composite Materials and Structures Group, Institut Clément AderUniversité de ToulouseToulouseFrance

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