Sifat Fisis Kayu Maesopsis eminii Engl. Termodifikasi Asam Borat, Minyak Nabati, dan Pemanasan

Abstract

Kayu manii (Maesopsis eminii Engl.) merupakan jenis cepat tumbuh dengan kelas awet rendah (IV) sehingga memerlukan pengawetan. Pengawet asam borat bersifat ramah lingkungan namun mudah mengalami ketercucian. Penambahan minyak nabati dan pemanasan diharapkan dapat memperbaiki sifat ketercucian pada asam borat. Penelitian ini bertujuan untuk mengevaluasi pengaruh perlakuan impregnasi asam borat, minyak nabati (mimba, nyamplung, kemiri), dan pemanasan terhadap sifat fisis kayu manii. Kayu manii diimpregnasi bertingkat dengan asam borat dan minyak nabati pada tekanan 7 kg cm-2 selama 4 jam, dilanjutkan dengan pemanasan suhu 70 ℃ dan 140 ℃ selama 4 jam. Pengujian mencakup kerapatan, berat jenis, ketercucian, daya serap air, stabilitas dimensi, dan perubahan warna. Hasil penelitian menunjukan perlakuan asam borat dan minyak nabati mempengaruhi nilai kerapatan, berat jenis, ketercucian, daya serap air, stabilitas dimensi, dan perubahan warna. Pemanasan suhu 140 ℃ menghasilkan peningkatan sifat fisis kayu lebih baik dari suhu 70 ℃. Penambahan minyak kemiri setelah perlakuan asam borat dengan suhu 140 ℃ menghasilkan peningkatan sifat fisis kayu manii yang paling baik seperti menaikan nilai kerapatan dan berat jenis, meningkatkan stabilitas dimensi, menahan ketercucian asam borat dengan perubahan warna kayu yang lebih merata dan menarik.

Manii wood is a fast growing wood with a low durability class (IV) so it requires preservation. Boric acid preservative is environmentally friendly but easily being leached. The addition of vegetable oil and heat treatment were expected to restrain the leaching of boric acid. This study aimed to evaluate the effect of impregnation treatment of boric acid, vegetable oils (neem, tamanu, hazelnut), and heat treatment on the physical properties of manii wood. Manii woods were double impregnated with boric acid and vegetable oils at a pressure of 7 kg cm-2 for 4 hours and heat treated at 70 ℃ and 140 ℃ for 4 hours. The physical properties tests of wood samples included density, specific gravity, leaching, water absorption, dimensional stability, and color changes. The results showed that the treatment of boric acid and vegetable oils affected the density, specific gravity, leaching, water absorption, dimensional stability, and color changes of manii wood. Heat treatment at 140 ℃ resulted in better physical properties of manii wood than 70 ℃ heating. The hazelnut oil treatment after boric acid preservation resulted in the best physical properties improvement of manii wood, such as increasing the density and specific gravity, improving dimensional stability, reducing preservative leaching and changing the color to be more even and attractive.