Papan partikel tanpa perekat sintesis atau binderlessboard merupakan alternatif produk ramah lingkungan yang potensial dikembangkan di Indonesia. Kelemahan produk tersebut diantaranya adalah kestabilan dimensinya yang relatif rendah. Alternatif perbaikan produk bisa dilakukan dengan menambahkan bahan pengaktif komponen kimia. Asam sitrat memiliki tiga gugus karboksil dan diharapkan dapat membentuk ikatan ester dengan gugus hidroksil pada permukaan kayu. Penelitian menggunakan asam sitrat relatif baru dan belum banyak dikembangkan, oleh karena itu penelitian ini ditujukan untuk pengembangan produk biokomposit dengan menggunakan asam sitrat sebagai bahan pengikat. Bahan yang digunakan adalah pelepah nipah dengan ukuran partikel (halus dan kasar), konsentrasi asam sitrat (0% dan 10%), dan suhu pengempaan (180oC dan 200°C). Pengujian sifat fisika dan mekanika dilakukan berdasarkan Japanese Industrial Standard untuk papan partikel (JIS A 5908). Penambahan asam sitrat memperlihatkan kenaikan sifat fisika (penyerapan air) dan mekanika papan partikel. Perbedaan ukuran partikel mempengaruhi sifat mekanika papan partikel dimana ukuran partikel kasar memberikan nilai mekanika yang lebih baik dibandingkan dengan ukuran partikel halus. Kualitas papan partikel optimum diperoleh pada kondisi pengempaan 180oC, penambahan asam sitrat 10% dari partikel ukuran kasar dengan nilai pengembangan tebal 2,4%, penyerapan air 41%, kekuatan rekat internal 0,2 MPa, modulus patah 5,5 MPa, dan modulus elastisitas 1,6 GPa. Kata kunci : asam sitrat, pelepah nipah, konsentrasi asam sitrat, suhu pengempa Effect of Citric Acid Concentration and Pressing Temperature on the Quality of Particleboard from Nypa Frond Abstract Binderlessboard is one of the potential eco friendly products that can be developed in Indonesia. However, its boards usually have low in dimensional stability. Addition of the chemical agent, such as citric acid, that can improve the dimensional stability is needed. Citric acid has three hydroxyl groups that can be ester-linked with hydroxyl groups from wood. Researches on citric acid and its utilization are relatively limited. This research focused on the development of particleboard using citric acid as bonding agent. Nypa frond was used as raw material with two different sizes of particles, namely fine and coarse particles. Addition of citric acid of 10% air-dried particles was done for improving the dimensional stability. Pressing temperature was set at 180oC dan 200°C during 15 minutes. Physical and mechanical properties were done according to Japanese Industrial Standard JIS A 5908. Addition of citric acid could improve physical and mechanical properties of the boards. Coarse particles provided the particleboards with better mechanical properties compared to fine particle. Boards that made from coarse particle and 10% citric acid at pressing temperature of 180oC have optimum properties, i.e. thickness swelling 2.4%, water absorption 41%, internal bond strength 0.2 MPa, modulus of rupture 5.5 MPa, dan modulus of elastisity 1.6 GPa.
[1]
K. Umemura,et al.
Application of citric acid as natural adhesive for wood
,
2012
.
[2]
K. Umemura,et al.
Characterization of wood-based molding bonded with citric acid
,
2011,
Journal of Wood Science.
[3]
S. Saka,et al.
Chemical characterization of various parts of nipa palm (Nypa fruticans)
,
2011
.
[4]
R. Widyorini,et al.
Some of the Properties of Binderless Particleboard Manufactured from Bamboo
,
2011
.
[5]
Takashi Watanabe,et al.
Self-bonding characteristics of binderless kenaf core composites
,
2005,
Wood Science and Technology.
[6]
Takashi Watanabe,et al.
Chemical changes in steam-pressed kenaf core binderless particleboard
,
2005,
Journal of Wood Science.
[7]
N. Okuda,et al.
Manufacture and mechanical properties of binderless boards from kenaf core
,
2004,
Journal of Wood Science.
[8]
Jianying Xu,et al.
Development of binderless particleboard from kenaf core using steam-injection pressing
,
2003,
Journal of Wood Science.
[9]
G. Nemli.
Effects of Some Manufacturing Factors on the Properties of Particleboard Manufactured from Alder (Alnus glutinosa subsp. Barbata)
,
2003
.