Svojstva i primjena pčelinjeg voska

undergraduate thesis

• Title (english): Properties and application of bee waxes
• Author: Božana Đuranović
• Mentor: Mirela Leskovac (mentor)
• Committee member: Mirela Leskovac (predsjednik povjerenstva)
• Committee member: Zrinka Buhin Šturlić (član povjerenstva)
• Committee member: Vesna Ocelić Bulatović (član povjerenstva)
• Granter: University of Zagreb; Faculty of Chemical Engineering and Technology; Zagreb
• Defense date and country: 2017-07-07, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Basic Technical Sciences; Materials

Abstract

Pčelinji vosak je proizvod pčela i najvažniji je prirodni vosak zbog svojih jedinstvenih svojstava i korisnih primjena u medicini, kozmetici, hrani, inženjerstvu i industriji. Pčelinji vosak je dostupan u dva oblika: žuti (Cera flava) i bijeli (Cera alba). Žuti pčelinji vosak dobiva se taljenjem saća vrućom vodom i filtriranjem nečistoća iz taline. Bijeli pčelinji vosak dobiva se izbjeljivanjem žutog pčelinjeg voska s kalijevim permanganatom, aktivnim ugljenom ili sunčevim zrakama. Vrlo čist pčelinji vosak je bijel, ali prisutnost peluda i drugih tvari uzrokuju da postane žut. Pčelinji vosak je složena mješavina ugljikovodika, karboksilnih kiselina, estera i alkohola. Cilj ovog rada bio je istražiti strukturna i toplinska svojstva različitih vrsta pčelinjih voskova (BW), domaće i komercijalne proizvodnje. Strukturna svojstva različitih pčelinjih voskova analizirana su pomoću FTIR-ATR spektroskopije a površinska svojstva dobivena su mjerenjem kontaktnog kuta. Toplinska svojstva pčelinjeg voska analizirana su proimjenom diferencijalne pretražne kalorimetrije (DSC) i termogravimetrije (TGA). Rezultati ukazuju da nečistoće uključene u pčelinjem vosku imaju značajan utjecaj na svojstva površine i na toplinska svojstva. Veća hidrofilnost prisutnih nečistoća doprinosi sniženju hidrofobnosti voska i sniženju toplinske stabilnosti.

Abstract (english)

Beeswax is a bee product and it is the most important natural waxes because of its unique properties and useful applications in medicine, cosmetics, food, engineering and industry. Beeswax is available in two forms, yellow (Cera flava) and white (Cera alba). Yellow beeswax is made by melting honeycombs with hot water and filtering out impurities from the melt. White beeswax is made by bleaching yellow beeswax with potassium permanganate, active carbon or sunlight. Very pure beeswax is white, but the presence of pollen and other substances cause it to become yellow. Beeswaxes are a complex mixture of hydrocarbons, carboxylic acids, esters and alcohols. The aim of this study was to investigate a structural and thermal properties of different kinds of beewaxes (BW), domestic and commercial one. Structural properties of different beewaxes were analysed by using FTIR-ATR spectroscopy and surface properties were obtained by using the contact angle measurement. Thermal properties of beeswaxes were investigated with a differential scanning calorimetry (DSC) and thermogravimetry (TGA). The results indicates that impurities incorporated in beeswaxes has a great influence on the surface as well as their thermal properties. Higher hydrophylity of impurities contributes to lowering hydrophobity of beewaxes and lowering their thermal stability.

• Keywords: pčelinji vosak; DSC; FTIR-ATR; TGA; kontaktni kut
• Keywords (english): beeswax; DSC; FTIR-ATR; TGA; contact angle
• Language: croatian
• URN:NBN: urn:nbn:hr:149:844815
• Study programme: Title: Environmental Engineering - Undergraduate study; Study programme type: university; Study level: undergraduate; Academic / professional title: sveučilišni/a prvostupnik/ prvostupnica (baccalaureus/baccalaurea) inženjer/inženjerka ekoinženjerstva (sveučilišni/a prvostupnik/ prvostupnica (baccalaureus/baccalaurea) inženjer/inženjerka ekoinženjerstva)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2020-12-15 11:30:37