The Characteristics of Citric Acid-Bonded Composite Boards Produced from Alkaline-Modified Fibrovascular Bundle of Salacca Sumatrana Fronds

ABSTRACT

Fibrovascular bundle (FVB) of Salacca sumatrana fronds is a natural fiber derived from palm plants. The fiber typically had long dimensions and the potential to be used as raw material for oriented boards. Therefore, this study aimed to evaluate the properties of oriented boards made from alkaline-modified FVB of Salacca sumatrana frond. FVB was modified with an alkali pre-treatment, comprising 1% NaOH, 1% NaOH + 0.2% Na₂SO₃, and 1% NaOH + 0.4% Na₂SO₃ to improve the dimensional stability. The sample was then manually formed into a three-layer oriented mat using a forming box, which was oriented at 3 different angles of 0°, 45°, and 90°. The results showed that the 1% NaOH + 0.2% Na₂SO₃ treatment gave the lowest thickness swelling and water absorption, as well as the highest modulus of rupture and elasticity values. Based on Fourier Transform Infrared (FTIR) analysis, there was a bond between FVB hydroxyl groups and the carboxyl groups in citric acid, showing an effective bonding mechanism. Furthermore, orientated boards with an orientation of 90° were the best among all chemically modified types. The results showed that the modified natural fiber of FVB formed a bond with citric acid, leading to excellent mechanical properties.

摘要

漆树叶的纤维维管束（FVB）是从棕榈植物中提取的一种天然纤维. 该纤维通常具有长尺寸，并且有潜力用作定向板的原材料. 因此，本研究旨在评估用碱改性苏门答腊黄FVB制成的定向板的性能. 用碱预处理对FVB进行改性，包括1%NaOH、1%NaOH +0.2%Na2SO3和1%NaOH +0.4%Na2SO3，以提高尺寸稳定性. 然后使用成型箱将样品手动成型为三层定向垫，成型箱以0°、45°和90°的3个不同角度定向. 结果表明，1%NaOH +0.2%Na2SO3处理的厚度膨胀率和吸水率最低，断裂模量和弹性值最高. 基于傅立叶变换红外光谱（FTIR）分析，柠檬酸中的FVB羟基和羧基之间存在键合，显示出有效的键合机制. 此外，在所有化学改性类型中，取向为90o的取向板是最好的. 结果表明，改性后的FVB天然纤维与柠檬酸形成结合，具有优异的力学性能.

KEYWORDS:

• Oriented board
• fibrovascular bundle
• salacca sumatrana
• frond
• alkaline modification
• natural fiber

摘要:

• 定向板
• 纤维血管束
• 苏门答腊萨拉卡
• 叶
• 碱性改性
• 天然纤维

Acknowledgments

The authors are grateful for the financial support provided by the post-doctoral grant 2023 from the Directorate of Research Universitas Gadjah Mada (UGM) (No. 3662/UN1.P.II/Dit-Lit/PT.01.03/2023) and UGM Reputation Improvement Team toward World Class University, Yogyakarta, Indonesia.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

The work was supported by the the post-doctoral grant 2023 from Universitas Gadjah Mada, Yogyakarta, Indonesia.