Biodegradation of TPS/PLA blends

Primjena polimernih materijala je danas postala nezaobilazna potreba u raznim sektorima industrije i poljoprivrede. Pretjerana potrošnja materijala na bazi nafte, koja dovodi do iscrpljivanja prirodnih resursa, potaknula je znanstvenike na istraživanje novih biorazgradljivih materijala koji se mogu koristiti za razne potrebe industrije. Biorazgradljivi materijali imaju sposobnost razgradnje u okolišu pod utjecajem mikroorganizama, vode, kisika i sunčeve svjetlosti. Osim pozitivnog utjecaja na okoliš, određeni biorazgradljivi materijali poput termoplastičnog škroba (TPS) su ekonomski povoljni zbog svoje pristupačnosti, dostupnosti i sposobnosti da smanje ovisnost tržišta o cijenama plastike koje diktira naftna industrija. U ovom je istraživanju ispitana biorazgradljivost polimernih mješavina koje se sastoje od termoplastičnog škroba i polilaktida (PLA), sa i bez dodatka limunske kiseline (LK). Ispitivanje je provedeno u skladu sa standardima ISO 14855 i ASTM D5338. Identifikacija i karakterizacija TPS/PLA mješavina koje su biorazgradljive temeljito su provedene korištenjem infracrvene spektrometrije s Fourierovim transformacijama (FTIR-ATR). Morfologija polimernih mješavina analizirana je pomoću skenirajuće elektronske mikroskopije (SEM). Uzorci su promatrani prije i poslije procesa biorazgradnje svjetlosnim mikroskopom i optičkim mikroskopom s polarizacijom zbog uvida u površinsku strukturu materijala. Praćena je i promjena mase tijekom 56 dana procesa biorazgradnje.The application of polymeric materials has become an indispensable need in various sectors of industry and agriculture. Excessive consumption of petroleum-based materials, which leads to the depletion of natural resources, has prompted scientists to explore new biodegradable materials that can be used for the various needs of the industry. Biodegradable materials have the ability to decompose in the environment under the influence of microorganisms, water, oxygen and sunlight. In addition to the positive impact on the environment, certain biodegradable materials such as thermoplastic starch (TPS) are economically advantageous due to their affordability, availability and ability to reduce the market's dependence on plastic prices dictated by the oil industry. In this study, the biodegradability of polymer mixtures consisting of thermoplastic starch and polylactide (PLA), with and without the addition of citric acid (LK), was examined. The test was conducted in accordance with ISO 14855 and ASTM D5338 standards. The identification and characterization of TPS/PLA mixtures that are biodegradable was thoroughly carried out using Fourier transform infrared spectrometry (FTIR-ATR). The morphology of polymer mixtures was analyzed using scanning electron microscopy (SEM). Samples were observed before and after the biodegradation process by light microscope and optical microscope with polarization for insight into the surface structure of the material. A change in mass during the 56 days of the biodegradation process was also monitored