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Polimeri su neizostavni dio modernog društva. Oni čine veliki dio svih većih industrija; prometa, građevinarstva, energije, poljoprivrede, tekstila, prehrane, farmacije, itd. Polimerni materijali upotrijebljeni u takvim industrijama mogu dolaziti u različitim oblicima i sadržavati različita svojstva. U ovom radu objašnjena su svojstva polimera, a težina je stavljena na njihova mehaničko toplinska svojstva. Opisane su norme određivanja toplinske postojanosti oblika pod opterećenjem (HRN EN ISO 75), određivanje temperature omekšavanja po Vicatu (HRN EN ISO 306) i metoda dobivanja temperature postojanosti oblika po Martensu. U eksperimentalnom dijelu rada potrebno je dostupni uređaj na katedri za preradu polimera poboljšati te pustiti u rad. Nakon toga provedena su ispitivanja temperature omekšavanja po Vicatu na četiri različitih plastomera za potvrdu ispravnosti uređaja. Polymers are indispensable materials to modern society. They constitute a large part of major industries, including transport, construction, energy, agriculture, textiles, food, pharmacy, etc. The polymers used in such industries come in different forms and contain various characteristics. This paper will examine the properties of various polymers and focus on their mechanical and thermal properties. The described standards include determination of temperature of deflection under load (HRN EN ISO 75), determination of Vicat softening temperature (HRN EN ISO 306), and Martens method for determining heat – deflection temperature. The experimental part of this paper discusses improvement and putting into service the machine at polymer processing department. Lastly, tests of determination of Vicat softening temperatures are carried out on four different thermoplastic materials to confirm machine accuracy. |
