Struktura i svojstva voskova

undergraduate thesis

• Title (english): Structure and properties of waxes
• Author: Marta Žulj
• 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: 2017-09-22, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Basic Technical Sciences; Materials

Abstract

Voskovi su sve krute ili tekuće tvari koje sadrže ugljikovodike, kiseline, alkohole i estere bez obzira na podrijetlo ili način dobivanja. Zbog njihove složene strukture nije ih jednostavno opisati i zato postoje razne podjele voskova. Prema podrijetlu dijele se na prirodne i sintetske. Prirodni voskovi su materijali biljnog ili životinjskog podrijetla a dobivaju se iz različitih sjemenki, povrća, izlučevina pčela i drugih insekata. Svojstva tih materijala razlikuju se od svojstava sintetskih voskova koji se dobivaju iz nafte, minerala i produkata nafte. Dobro su poznati prirodni voskovi karnaube, soje, montana, šelak i pčelinji vosak ali njihova količina je znatno manja u usporedbi sa sintetskim voskovima koji se dobivaju iz nafte. U ovom radu istražena su svojstva šest voskova, tri prirodna i tri sintetska. Strukturna analiza voskova provedena je primjenom FTIR-ATR spektroskopije a površinske karakteristike mjerenjem kontaktnog kuta. Toplinska svojstva voskova analizirana su pomoću diferencijalnog pretražnog kalorimetra. Analiza gorenja provedena je na svijećama pripravljenim od različitih voskova te je procijenjena brzina gorenja.

Abstract (english)

Waxes are all solids and liquids found in nature, and to those that occur individually in waxes, such as the hydrocarbons, acids, alcohols, and esters irrespective of their source or method of preparation, provided such couslituents are waxlike in their properties. Because of their complex structure, it is not easy to describe them and because of this there is different waxes classification. By the origin, they are divided into natural and synthetic. Natural waxes are materials made from plant and animals derived from vegetables, beans, bees and other insects. Natural waxes have properties different from synthetic waxes derived from crude oil, mineral or petroleum products. Well known natural waxes are carnauba, soya, montan, beeswax, schelak, but their quantity is very small compared to crude oil and synthetic waxes. Paraffin is synthetic wax a mixture of aliphatic or saturated hydrocarbons recovered from crude oil by distillation. In this study properties of six waxes are investigated, three from natural sourceand three synthetic. Structural analysis of waxes were performed by using FTIR-ATR spectroscopy and surface characteristics by using contact angle measurement. Thermal properties of waxes were analyzed by using differential scanning calorimetry (DSC). Analysis of burning were performed on the candles prepared from different waxes and velocity of wax burning is estimated.

• Keywords: vosak; parafin; sojin vosak; pčelinji vosak; toplinska svojstva
• Keywords (english): waxes; paraffin; soya bean wax; beeswax; thermal properties
• Language: croatian
• URN:NBN: urn:nbn:hr:149:583399
• Study programme: Title: Materials Science and Engineering - Undergraduate study; Study programme type: university; Study level: undergraduate; Academic / professional title: sveučilišni/a prvostupnik/ prvostupnica (baccalaureus/baccalaurea) inženjer/inženjerka kemijskog inženjerstva (sveučilišni/a prvostupnik/ prvostupnica (baccalaureus/baccalaurea) inženjer/inženjerka kemijskog inženjerstva)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2021-06-10 12:41:19