9026 KB0 KB201120252022Kordiš, AljažŠernek, Milanštevilka:1letnik:12str. 1-16DOI:10.18690/analipazu.12.1.1-18.2022COBISSID_HOST:106454787ISSN:2232-416XURN:URN:NBN:SI:doc-06UYVDDZslPAZUAnali PAZUadhesive bondgluinglepilni spojlepljenjelespolistirenpolystyrenereciklažarecyclingwoodLepljenje lesa z lepilom iz odpadnega polistirena|Each year the world produces more and more durable plastic waste, which is accumulating in nature. One of the solutions to ease its impact is to recycle and reuse it for new products and intermediate products. Recycled plastic, especially thermoplastic, has great potential in the wood industry. In our research, we have used waste coffee cups and spoons made of polystyrene to make two adhesive mixtures, using dimethylformamide as a solvent. To establish the shear strength of adhesive bonds, we made bonded wood panels according to the instructions by standard SIST EN 205:2016. The idea was to optimize the temperature of hot pressing and to add a cooling procedure to ensure better shear strength of the bond, which is needed to reach the minimum criteria of the SIST EN 204:2016 standard. We used two temperatures for hot pressing (150 °C and 120 °C) and four ways of panel cooling in a closed press. After trying out different procedures, we came to the conclusion that the best way to use a coffee cup adhesive is to cool it down to 75 °C, while for the spoon-based adhesive the best bonding method is to cool the joints down to 100 °C or 25 °C. We also found that by cooling the panels in a closed press the consistency of the results increases, which makes the adhesive bonds more reliable. We managed to reach standard criteria with a sample which had been glued with coffee cup adhesive, hot pressed at 150 °C and cooled down to 75 °C before being taken out of the pressVsako leto svet proizvede čedalje več obstojnih plastičnih odpadkov, ki se kopičijo v naravi. Ena izmed rešitev je njihova reciklaža in ponovna uporaba za izdelavo novih izdelkov ali polizdelkov. Reciklirana plastika, predvsem termoplasti, imajo potencial tudi v lesarstvu. V naši raziskavi smo iz odpadnih kavnih lončkov in žličk iz polistirena ter s topilom dimetilformamid izdelali lepilni mešanici in izdelali lepljence iz lesa za ugotavljanje strižne trdnosti lepilnih spojev po standardu SIST EN 205:2016. Uporabili smo dve temperaturi stiskanja (150 °C in 120 °C) ter štiri načine temperiranja oziroma ohlajanja lepljencev pred odprtjem stiskalnice. S primerjavo različnih postopkov lepljenja smo ugotovili, da lepilo iz lončkov najvišjo trdnost doseže po ohladitvi lepljencev na 75 °C preden smo jih vzeli iz stiskalnice, medtem ko lepilo iz žličk po hlajenju lepljencev na 100 °C ali 25 °C. Ugotovili smo tudi, da se s hlajenjem lepljencev na nižjo temperaturo pred odprtjem stiskalnice bistveno zmanjša variabilnost rezultatov, kar priča o bolj zanesljivih lepilnih spojih. Zahteve standarda SIST EN 204:2016 smo uspeli doseči z lepljencem, ki je bil zlepljen z lepilom iz lončkov pri temperaturi 150 °C in ohlajen na 75 °C preden smo ga vzeli iz stiskalniceTEXTznanstveno časopisjejournalsSlovenian National E-content AggregatorNational and University Library of SloveniaZdruženje Pomurska akademsko znanstvena unija