Judul: Sythesis of Poly  (Hydroxy) Urethane from Polyol and Liquefied Spruce Bark for Wood Impregnation
Abstrak: The finding and application of environmentally benign wood preservatives is becoming paramount. Nontoxic and less leachable or degradable chemical have been suggested for exterior application. Polyurethanes synthesized through a green chemical pathway is very promising environmentally friendly wood modification processes. In this study, non-isocyanate route of polyurethane synthesis based on polyol (i.e. xylitol, sorbitol, liquefied spruced bark, glycerol and PG3), alkyl carbonate (i.e. DMC and DEC) and diamine (i.e. HMDA, EDA and DETA) was realized for wood impregnation through in-site polymerization. The structure and mass average molecular weight (Mw) of polyurethanes synthesized and impregnated were then analyzed by using FTIR, NMR and SEC. According to the results, synthesis of polyurethane by two pot method in water brought to cyclic carbonate degradation. The using of DEC in transcarbonatation reaction in two pot method gave similar characters of FTIR spectrum to the use of DMC, however the used of DMC was simpler than that of DEC. The synthesis of polyurethane by one pot method using different diamines confirmed the presences of carbamate function as analyzed by FTIR. However, the visual appearance of polymers produced showed that the use of HMDA as diamine resulted a solid product that was less water-soluble compared to that resulted from the used of EDA and DETA. The distribution of mass average molecular weight (Mw) of polyurethanes synthesized determined by SEC showed that the most satisfying polymer with Mw of 4380 g/mol was prepared without solvent. The reaction in water produced polymers with low Mw (less than 750 g/mol). Polyurethanes synthesized in methanol has higher Mw than that in water. In the same solvent, the use of HMDA resulted in a polymer with higher Mw than that of using EDA. Wood impregnations using one step method using solvent gave unsatisfactory WPG (about 12.59 – 19.71 %) and LC (about 50.36 – 62.80 %). One step impregnation without solvent gave higher WPG (about 78.39 – 87.63 %) and lower LC (19.11 – 21.25 %). However, wood impregnation without solvent is not feasible to be applied industrially. In other hands, five conditions of two step impregnations performed gave WPG of about 14.89 – 30.73 % and LC of about 42.22 – 56.52 %. In the case of two step impregnations without solvent, the first impregnation left inadequate space for the retention of the second step. It corresponds rather to leaching. Moreover, wood impregnation in two step faced a constrain of reaction stoichiometry. Since it is not applicable in charge with wood impregnation using methanol or ethanol as the solvent is more recommended by comparing with impregnation with an aqueous solution. However, it needs improvement on its resistance against leaching when used outdoor.
Keyword: polyurethane, polyol, alkyl carbonate, diamine, liquefied bark, wood impregnation

Judul: Characteristics of Lignin-Based Polyurethane Adhesive with Biopolyol Modification for Plywood
Abstrak: Perekat poliuretan berbasis lignin dengan modifikasi biopoliol dapat dijadikan substitusi perekat Urea Formaldehida (UF) untuk kayu lapis karena dapat digunakan sebagai perekat eksterior, lebih ramah lingkungan, dan tidak menghasilkan emisi formaldehida. Penelitian ini bertujuan untuk menganalisis pengaruh penambahan konsentrasi PVOH/Lignin terhadap karakteristik perekat dan kayu lapis. Perekat dibuat dengan mencampurkan Metilen Difenil Isosianat (MDI), poliol, Poly Vinyl Alcohol (PVOH), dan lignin kemudian diaplikasikan pada vinir dengan suhu kempa 120 ℃ selama 4 menit. Rendemen lignin yang diperoleh yaitu 36,17%. Semakin tinggi konsentrasi Lignin/PVOH maka kadar padatan semakin menurun sedangkan viskositas, kohesi, torsi, storage modulus, loss modulus, dan tan delta mengalami peningkatan. Pada analisis FTIR, gugus penanda terbentuknya ikatan uretan teridentifikasi pada perekat ataupun kayu lapis. Formula perekat poliuretan berbasis lignin F1, F2, dan F3 memenuhi nilai delaminasi, keteguhan rekat, dan kerusakan kayu berdasarkan SNI (01-5008.7-1999). Pada formula tersebut gugus -OH dari lignin ataupun dari kayu lapis dapat berikatan dengan gugus -NCO sehingga memiliki sifat kohesi dan sifat adhesi yang baik., Lignin-based polyurethane adhesive with bio polyol modification can be used as a substitute for Urea Formaldehyde (UF) adhesive for plywood because it can be used as an exterior adhesive, is more environmentally friendly, and does not produce formaldehyde emissions. This study aims to analyze the effect of adding PVOH/Lignin concentration on the characteristics of the adhesive and plywood. The adhesive is made by mixing Methylene Diphenyl Isocyanate (MDI), polyol, Poly Vinyl Alcohol (PVOH), and lignin, then applied to the veneer with a compression temperature of 120 ℃ for 4 minutes. The yield of lignin obtained was 36.17%. The higher the concentration of Lignin/PVOH, the solids content decreased, while the viscosity, cohesion, torque, storage modulus, loss modulus, and tan delta increased. FTIR analysis identified markers for forming urethane bonds in adhesives or plywood. The lignin-based polyurethane adhesive formulas F1, F2, and F3 comply with delamination, tensile shear strength, and wood failure values according to the Indonesia National Standard (SNI 01-5008.7-1999). In this formula, the -OH group from lignin or plywood can form bonds with the -NCO group, resulting in good cohesion and adhesion properties.
Keyword: adhesion, cohesion, lignin, plywood, polyurethane adhesive

Judul: Beberapa aspek anatomi alat sirkulasi ruang dada kancil
Abstrak: Telah dilakukan penelitian dengan menggunakan 10 ekor kancil dewasa jantan dan betina dengan tujuan untuk menge- tahui beberapa aspek anatomi alat sirkulasi di dalam ruang dada, meliputi jantung, pembuluh darah yang keluar dan ma- suk jantung serta ukuran-ukuran jantung. Kancil merupakan ruminansia terkecil di dunia, hidup di daerah tropika India, Thailand, Malaysia dan Indonesia bagian barat. Hewan ini dilindungi dan mempunyai prospek yang baik untuk hewan penelitian maupun dibudidayakan. Hasil penelitian menunjukkan bahwa berat jantung rаta-rata adalah 0.69% dari berat rata-rata kancil. Dan ini mirip pada jantung kuda dan anjing. Bentuk jantung lonjong seperti halnya ruminansia. Demikian pula letaknya di dalam ruang dada seperti pada ruminansia dengan adanya Ligamentum sternopericardiacum. Di dalam ventrikel kanan membersit sebuah Musculus (M.) papillaris dari dindingnya dan tiga sampai empat Musculi (Mm.) papillares dari Septum interventriculare. Hanya dua buah Mm. papillares yang berukuran besar dibersitkan dari dinding ventrikel kiri. Percabangan Arteri (A.) coronaria sinistra lebih dominan dari pada A. coronaria dextra. Sedangkan A. sub clavia sinistra dicabangkan langsung dari aorta di dorso- caudal pembersitan Truncus (Tr.) brachiocephalicus…
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