Surface Characteristics and Acoustical Properties of Bamboo Particle Board Coated with Polyurethane Varnish

Using bamboo particle board as a wall divider, a furniture component, or an automotive component with a sound absorber function may be a viable option for architects and engineers seeking to achieve desired acoustical qualities, including noise reduction. However, there is still a dearth of research on the effect of particle board finishing and coatings on acoustical sound absorption and noise reduction qualities. This study, therefore, aims to determine the surface characteristics and acoustical properties of bamboo particle board, coated with polyurethane (PU). The single-layer homogeneous particle boards were constructed using particles classified as fine and coarse with two different board densities, and coated with a high-quality PU lacquer. This study found that the coating treatment of 0.3 mm 0.6 mm succeeded to significantly decrease surface roughness, as well as thickness, swelling, and water absorption, with the thickness coating as a dominant factor compared with board density and board particle size. Adding a PU coating increases sound absorption performance at low frequencies, but significantly reduces acoustical properties at high frequencies. The increase of particle board density leads to the decrease in noise reduction coefficient capability. Results obtained from this study are useful to determine the optimal coating thickness in terms of evaluating acoustical panel products.

Effect of Nano-additive on the Bonding Strength and Formaldehyde Emission of the Plywood Adhesive during Manufacturing of Wood Based Panel Products

Nano science and nano technology provides numerous opportunities for enhancing the properties of wood based panel products. In this study an extender was made using nano silicon dioxide ( Sio2), nano calcium carbonate( CaCo3) with some specialty chemicals at a certain reciprocal proportion. Efficacy study was carried out with both phenolic and amino resin in terms of rheological and formaldehyde emission test using reinforcement of nano additive as extender at different concentration level. The plywood panels has been tested as per IS: 1734-1983 for mechanical properties. The rheological and adhesive properties has been tested as per IS 848: 2006. The test data reveals that enhancement of rheological, bonding and mechanical properties have been achieved after reinforcement of synthetic resin. The increase in the percentage of nano-additive caused an increase of viscosity, glue shear strength and minimizing the formaldehyde emission than using individual nano silicon dioxide ( Sio2), nano calcium carbonate( CaCO3) instead of the extender made by combination of above. Using nano additive extender at 5%, there is an increase in glue shear strength in the glue line and enhanced rheological properties in amino resin based adhesive was observed.

Micro-Fibrillated Cellulose in Adhesive Systems for the Production of Wood-Based Panels

Micro-Fibrillated Cellulose (MFC) is a new type of bio-based additive, coming from wood cellulose. It can compete and substitute oil derived chemicals in several application fields. In the present work, the use of micro-fibrillated cellulose, in waterborne adhesive systems applied in the manufacture of composite wood-based panels was evaluated. Research was conducted to test the potential of improving the performance of wood-based panel types such as particleboard, waferboard or randomly-oriented strand board and plywood, by the application of MFC and the substitution of conventional and non-renewable chemical compounds. The approaches followed to introduce MFC into the adhesive systems were three, i.e., MFC 2% suspension added during the adhesive resin synthesis, MFC 10% paste admixed with the already prepared adhesive resin and MFC 2% suspension admixed with the already prepared resin. It was found that MFC improves not only the performance of the final wood panel products but also the behaviour of the applied adhesive polymer colloids (e.g., rheology improvement), especially when admixed with the already prepared resins. Moreover, it was proven that when MFC is introduced into the adhesive resin system, there is a possibility of decreasing the resin consumption, by maintaining the board performance. MFC’s robustness to pH, shear and temperature makes it a highly interesting new additive for adhesive producers. In addition, its natural origin can give adhesive producers the opportunity to move over to more environmentally friendly product solutions.

Sifat Dasar Kayu Ganitri (Elaeocarpus sphaericus (Gaertn.) K. Schum.) dari Sukabumi dan Potensi Penggunaannya

Ganitri (Elaeocarpus sphaericus (Gaertn.) K. Schum.) adalah pohon cepat tumbuh yang banyak ditemukan di Sukabumi. Kayu ini tumbuh di hampir semua wilayah Indonesia. Tulisan ini menyajikan hasil pengujian sifat dasar (struktur anatomi, kimia, sifat fisis dan mekanis) kayu ganitri yang diambil dari hutan rakyat di daerah Sukabumi. Tujuan penelitian adalah untuk mengetahui potensi penggunan kayu ganitri berdasarkan sifat dasar dan penggunaan kayu oleh masyarakat sekitar. Hasil penelitian menunjukkan bahwa kayu ganitri memiliki kayu teras berwarna kuning dan kayu gubal berwarna putih. Corak kayu polos dan tekstur halus. Arah serat lurus sampai berpadu, kayu lunak, tidak mengkilap, dan tidak berbau. Berdasarkan nilai dimensi serat dan nilai turunannya, kayu ganitri termasuk ke dalam Kelas Mutu II. Kayu ganitri memiliki kadar holoselulosa dan selulosa yang tinggi (70,70% dan 54,58%), kadar sedang untuk lignin 21,60%, ekstraktif alkohol-benzena 3,47%, dan kadar abu 0,81%. Dengan berat jenis (BJ) kering udara 0,35 kayu ganitri termasuk ke dalam Kelas Kuat IV. Kayu tersebut disarankan untuk digunakan sebagai bahan bangunan konstruksi ringan, perkakas, furnitur, kayu lapis, papan sambung dan produk panel. Basic Properties of Ganitri Wood (Elaeocarpus sphaericus (Gaertn.) K. Schum from Sukabumi and Its Potential UsesAbsractGanitri (Elaeocarpus sphaericus (Gaertn.) K. Schum.) is a fastgrowing tree that is widely found in Sukabumi, West Java. It grows in all part of Indonesia. A research was carried out to investigate basic properties (anatomical, physical, mechanical, and chemical) of ganitri wood from the community forest of Sukabumi. The purpose of this study was to determine the potential use of ganitri wood based on its basic properties and local utilization. The results showed that the color of ganitri sapwood was white , and it was not clearly demarcated from the yellow, with fewer figure patterns. The texture was fine with straight to interlocked grain. The wood was soft, not lustrous, and no special odor. Based on the fibre dimensions and derivative values, the quality of ganitri wood fell in Class II as a raw material for pulp and paper. Ganitri had high holocellulose and cellulose levels (70.70% and 54.58%), moderate level in lignin (21.60%), and it contained 3.47% extractive soluble in alcohol-benzene, and 0.81% ash. Based on its air dry specific gravity (0,35), ganitri wood could be classified into wood Strength Class IV. The potential uses of ganitri are for lightweight construction material, tools, furniture, plywood, connecting boards, and other panel products.