20.500.12556/RUL-406 Vpliv deleža utekočinjenega lesa v urea-formaldehidnem lepilu na lastnosti ivernih plošč diplomsko delo - univerzitetni študij Impact of share of liquefied wood in urea-formaldehyde adhesive on properties of particleboards graduation thesis - university studies V zadnjih letih je opazen porast raziskav na področju rabe utekočinjenega lesa, predvsem kot goriva oz. kot surovine za izdelavo poliuretanskih pen. Preučevali smo možnost nadaljnje uporabe utekočinjenega lesa in sicer kot vezivnega sredstva za iverne plošče. V laboratorijskih pogojih smo izdelali 3-slojne iverne plošče z različnim deležem utekočinjenega lesa (10 %, 20 %, 30 %, 40 %, 50 %, in 75 %). Les je bil utekočinjen po polihidrični metodi. Opazovali smo razslojno trdnost, čvrstost površine, debelinski nabrek in vsebnost prostega formaldehida, ki smo ga določali po perforator metodi. Razslojna trdnost in čvrstost površine se izboljšata, če je delež utekočinjenega lesa 10 % oz. 20 %. Pri debelinskem nabreku pa utekočinjeni les ne zmanjša absorbcije vode, ampak jo celo poveča. Vsebnost prostega formaldehida se močno zmanjša: najnižjo vrednost pa dosežemo z dodatkom 20 % utekočinjenega lesa. In the last few years, there is a noticeable increase in research of liquefied wood, used for fuel or as a raw material for polyurethane foam production. The possibilities of further usage of liquefied wood, as an adhesive for particleboards, were examined. In the laboratory conditions 3-layer particleboards with various portions of liquefied wood (10 %, 20 %, 30%, 40 %, 50 % and 75 %) were prepared. The wood was liquefied according the polyhydric method. We studied internal bond, surface soundness, thickness swelling and emission of free formaldehyde, determined by perforator procedure. It was found out that the internal bonds and surface soundness improved by addition of 10 % or 20 % liquefied wood. Concerning the thickness swelling, liquefied wood does not reduce the absorption of water, on the contrary, it does increase it. Emission of free formaldehyde highly reduces: the lowest level is gained by adding 20 % of liquefied wood. utekočinjen les iverna plošča UF lepilo razslojna trdnost čvrstost površine debelinski nabrek formaldehid liquefied wood particleboard UF adhesive internal bonds surface soundness thickness swelling formaldehyde true false false [A. Potisek Križ] Slovenski jezik Angleški jezik Diplomsko delo 2014-07-11 12:25:27 2014-07-11 12:25:27 2025-08-08 13:19:16 0000-00-00 00:00:00 2009 0 Ljubljana 0 VIII, 54 f. 0000-00-00 NiDoloceno NiDoloceno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 630*862.2 1759369 dn_potisek_kriz_aleksandra.pdf dn_potisek_kriz_aleksandra.pdf 1 83A8696A101DF3A3E39E945B3FE881B4 824e68b212ed4d6b721d5e3da1ea94d352254e68dee0e071642f1060eb9130cb 5ee3e31a-a1b9-11eb-a523-00155dcfd717 20.500.12556/rul/a347975d-7077-446e-bd49-1462230b2768 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=132332 Biotehniška fakulteta 0 0 0