20.500.12556/RUL-152426 Vpliv večkratnega recikliranja odpadkov široke potrošnje na mehanske, termične in površinske lastnosti Effect of multiple recycling of post-consumer waste on mechanical, thermal and surface properties Problem kopičenja plastičnih odpadkov predstavlja poleg onesnaževanja okolja socialen, tehničen in ekonomski problem. Polietilen visoke gostote (HDPE) je eden izmed pogosto uporabljanih polimernih materialov, saj je nezahteven za predelavo, ima dobro trdnost in žilavost. V sklopu magistrske naloge smo ugotavljali, ali se že 10-krat recikliranemu HDPE, pridobljenem iz odpadnih zamaškov iz različnih virov, ob nadaljnjem recikliranju spreminjajo mehanske, termične in površinske lastnosti. Z nateznim preizkusom smo preverjali natezno trdnost, z metodo diferenčne dinamične kalorimetrije (DSC) smo določali temperaturo taljenja, temperaturo kristalizacije, spremembe entalpij pri taljenju in kristalizaciji, s postopki nanoindentacije pa smo preverjali lastnosti površine, kot so elastični modul, trdota, modul akumulacije energije, modul energijskih izgub in profil površine pri razenju. Ugotovili smo, da se prej omenjene veličine pri opazovanem materialu, ki smo jih merili, do vključno 25. cikla recikliranja ne spremenijo za več kot 10% v primerjavi z izhodiščnim materialom za recikliranje. The problem of accumulating plastic waste represents not only an environmental pollution issue but also a social, technical, and economic problem. High-density polyethylene (HDPE) is one of the commonly used polymer materials because it is easy to process, has good strength, and toughness. As part of the master's thesis, we investigated whether the mechanical, thermal, and surface properties of HDPE, obtained from recycled bottle caps from various sources, which has already been recycled 10 times, change with further recycling. Tensile testing was used to assess tensile strength, the differential scanning calorimetry (DSC) method was employed to measure melting temperature, crystallization temperature, changes in enthalpy during melting and crystallization, and nanoindentation procedures were used to examine surface properties such as elastic modulus, hardness, energy storage modulus, energy loss modulus, and surface profile during indentation. We found that the mentioned properties in the observed material, which we measured, remain unchanged up to and including the 25th recycling cycle, with changes of no more than 10% compared to the original recycled material. Polietilen visoke gostote recikliranje brizganje natezni preizkus diferenčna dinamična kalorimetrija nanoindentacija High density polyethylene recycling moulding tensile test differential scanning calorimetry nanoindentation true false false [V. Gale] Slovenski jezik Angleški jezik Magistrsko delo/naloga 2023-11-24 09:51:51 2023-11-24 09:51:56 2024-01-30 09:46:56 0000-00-00 00:00:00 2023 0 Ljubljana 0 XXIV, 88 str. 0000-00-00 NiDoloceno NiDoloceno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 502.174.1:620.28:531(043.2) 259626 182963203 32524.pdf 32524.pdf 1 B7A08C206925960D672AE2135C42BA9F 0cbb3058ca41f093a71b26f6ea4fe02411a5a2130bac6f8156ef424eafe4f51f ba08335f-8aa6-11ee-8840-0050569b8976 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=177943 Fakulteta za strojništvo 0 0 0