Effect of Green Tea Content on Dynamic Modulus of Elasticity of Hybrid Boards Composed of Green Tea and Wood Fibers, and Prediction of Static Bending Strength Performances by Flexural Vibration Test

Abstract

In this study, eco-friendly hybrid composite boards were manufactured from green tea and wood fibers for application as interior materials with various functionalities of green tea and strong strength properties of wood fibers. In this relation, the effect of green tea content on dynamic MOEs (modulus of elasticity) of these green tea and wood fibers composite boards were investigated. The dynamic MOEs of hybrid composite boards were lower than those of control boards without green tea, and the values decreased with the increase of green tea content. Also, the dynamic MOEs appeared to be somewhat different by resin type used for board manufacture. The hybrid composite boards manufactured from E1 grade urea resin, which has higher molar ratio of formaldehyde to urea than that of E0 grade one, were 1.06∼1.54 times higher than that manufactured from E0 grade. And, the differences between hybrid composite boards manufactured from both adhesive increased with the increase of green tea content. On the other hand, high correlations were found between dynamic MOE and static bending strength performances, it was concluded that static bending strength performances could be estimated from the dynamic MOE, except for a few hybrid board types with large variations.

Relation between the dynamic modulus of elasticity and the static modulus of elasticity, the modulus of rupture of mandarin peel–sawdust composite board

“…These indicate that the relation between the dMOE and sMOE, and relation between the dMOE and MOR of mandarin peelsawdust composite boards have highly close linear correlation. This is in agreement with the results of the relation between the dMOE and sMOE of the green tea-wood fiber composite board [5]. Therefore, it is suggested that the sMOE and MOR can be predicted from the dMOE of mandarin peel-sawdust composite boards, measured by free vibration test using resonance frequency.…”

Properties of Board Manufactured from Sawdust, Ricehusk and Charcoal

“…한편, 목질재료는 기존의 목재소재로만 제조되던 것이 점차 기능성이 포함된 재료가 혼합된 친환경 재료로 변화하고 있다. 특히, 내구성과 기능성을 고려한 다양한 친환경재료의 연구와 개발이 이루어지고 있다 (Park et al, 2013;Park et al, 2012;Hwang and Oh, 2017)…”

“…On the other hand, wooden raw materials are being gradually transformed from thoseoriginally manufactured only for wooden materials into compounded environmentally friendly materials which include functionality. A variety of research and development in particular is making progress regarding environmentally friendly materials which take into consideration their durability and functionalities (Park et al, 2013;Park et al, 2012;Hwang and Oh, 2017). Charcoal is the most easily accessible environmentally friendly material, and its usable field is being widened as further new use methods are being developed after identifying numerous features such as air and water purification, far-infrared radiation release, electromagnetic wave shielding, etc.…”

“…Also, Seo & Lee (2010) manufactured black coal boards by using biologically and environmentally friendly natural plasmatic concentrated additive, and confirmed that it could be utilized as a residential environmental material for indoor air quality management. Also, Park et al (2012Park et al ( , 2013 used green tea, charcoal and wooden fabric to manufacture the compounded boards in various conditions andmeasure their material properties, and carried out research relevant to material development as an environmentally friendly material. Hwang & Oh (2017) investigated the material properties of boards manufactured using rice husk and charcoal, whereas Kim (2017) had manufactured boards by using ricehusk and charcoal to develop insulating materials for structural purposes.…”

Dynamic Modulus of Three-Layer Boards with Different Furnish and Shelling Ratio

“…Previous studies have provided the results of investigations over the bending properties of wood and wood-based composites by using the NDE test (Marra et al, 1966;Teixeira and Moslemi, 2001;Hu et al, 2005aHu et al, , 2005bMoya et al, 2010;Park et al, 2011). Since prior experimental works have shown a good correlation between NDE and the static modulus of elasticity (MOE) of wood-based composites (Teixeira and Moslemi, 2001), the current study would focus on the potential of NDE test by examining three-layer particleboards with different particle type and wood species.…”