Cellulose from plants is a natural polymer that is very abundant, cheap and easy to process. In addition, there is bacterial cellulose produced from bacterial fermentation of acetic acid with limited production but has high purity, crystallinity, and tensile strength. In this research, the process of wood-veneer delignification was carried out to self-assembly bacterial cellulose into wood cavities on bacterial culture media. Wood veneer reinforced bacteria cellulose was given heat pressure to increase the density and it was expected to form hydrogen bonds between their cellulose molecular chains. This study observed the duration of fermentation in bacterial media culture on the tensile strength of hybrid veneers, microscopic observations, the effect of water on set-recovery, and the characteristics of solid veneers on cyclic loading and temperature using dynamic mechanical analysis (DMA) testing. The microscopic observations prove that Acetobacter xylinum can penetrate the veneer and assemble bacterial cellulose in the cavity. A higher tensile strength ratio of 81.38% was observed in densified veneers with a five-day fermentation period with a modulus of elasticity 156.63% higher than natural veneers. The minimum set-recovery after boiling the hybrid veneer was 29.32%. DMA showed that by reinforcing wood veneer with bacterial cellulose and compacting, it increased cyclic energy storage ability, reduced energy loss, and increased stability under increasing temperatures. Strengthening wood with bacterial cellulose in this method opens new potential for developing more environmentally friendly forest products in the future.

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Cement board is a composite made from lignocellulosic biomass or other materials and bonded with cement, that has advantages such as fire and termite resistance, and can use for some purposes. The cement board’s quality is affected by the biomass’s chemical components, especially hemicellulose and extractives. Treatment to reduce the content of these two compounds in fiber can improve the cement board quality. This study aimed to evaluate the cement board’s properties reinforced with coconut coir fiber (CCF). Pretreatment was performed on fibers by soaking in cold water for 24 hours and soaking in hot water for 1 hour to reduce the chemical compounds. The ratio between fiber-cement used varied to 1:2.75, 1:3.0, and 1:3.25 based on weight, while magnesium chloride (MgCl2) uses at 2.5% of cement weight as an accelerator. The mixtures hand-matt formed and cold-pressed for 24 hours, with a density of the board was 1.25 g/cm3. The panels kept for 28 days before tested. Physical and mechanical tests conducted according to ISO 8335-1987. Results showed that the cement board’s physical and mechanical properties made from CCF soaked in hot water at the ratio fiber to the cement of 1:3.25 is the best properties compared to others.

Wood is the largest source of cellulose in the nature however it has a low strength. In other hand, bacteria cellulose as a pure cellulose has a higher tensile strength than wood. Wood reinforced with bacterial cellulose was produced by self-assembly approach with veneer soak into the fermentation medium. The product of this research is hybrid veneer processed thermos-hydro-mechanical treatment. It has been used to give a change in its mechanical properties. This research analyzed mechanical tensile test, Fourier transform infrared spectroscopy, and field emission scanning electron microscopy. The result showed that bacteria cellulose had impact to increase tensile strength of veneer and improve the molecular strength between cellulose fibers. Hydrogen bonds were formed between veneer fibers and bacterial cellulose then those bonds stick together and resulted in strong adhesion.

Beton busa (Foamed Concrete) adalah salah satu jenis beton ringan yang terdiri dari pasta semen atau mortar, dimana ruang udara atau pori-pori strukturnya terbentuk dengan menambahkan foaming agent kedalam campuran. Penelitian ini bertujuan untuk mengetahui pengaruh penggunaan abu ampas tebu sebagai bahan penganti semen dalam pembuatan beton busa ringan (lightweight foamed concrete).  Bahan-bahan yang digunakan dalam penelitian ini adalah Semen Portland tipe I, abu ampas tebu, pasir, foaming agent dan air. Mix design yang digunakan dalam penelitian ini sesuai dengan ASTM C 796 -97 dengan kuat tekan yang diharapkan sebesar 1,4 MPa. Kuat tekan tertinggi yang dihasilkan pada umur 28 hari sebesar 1,2 MPa sampai 1,9 MPa. Kuat tekan terbesar didapat pada beton busa ringan dengan kadar abu ampas tebu 12%. Sedangkan berat jenis sebesar 1014 – 1037 kg/m3 dan kuat lenturnya sebesar 0,69 – 1,38 MPa.