Svojstva i primjena prirodnih adheziva

undergraduate thesis

• Title (english): Properties and application of natural adhesives
• Author: Irena Milardović
• Mentor: Mirela Leskovac (mentor)
• Mentor: Zrinka Buhin Šturlić (komentor)
• Committee member: Mirela Leskovac (predsjednik povjerenstva)
• Committee member: Zrinka Buhin Šturlić (član povjerenstva)
• Committee member: Marijana Kraljić Roković (član povjerenstva)
• Granter: University of Zagreb; Faculty of Chemical Engineering and Technology; Zagreb
• Defense date and country: 2020-09-14, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Chemical Engineering

Abstract

Pojam adheziva poznat je još od davnina, a upravo su prvi primjenjivi adhezivi bili prirodnog podrijetla, podrazumijevajući sve adhezive na biljnoj i životinjskoj bazi te prirodne gume. Njihova pristupačna cijena i dobra kvaliteta i danas omogućuje široku primjenu, ponajviše u drvnoj i prehrambenoj industriji gdje se najviše cijeni njihovo prirodno podrijetlo. U ovome je radu dan pregled prirodnih adheziva biljnog i životinjskog podrijetla te su ispitana svojstva četiri vrste prirodnih adheziva. Šelak i goveđe tutkalo adhezivi su životinjskog podrijetla a svoju primjenu nalaze u drvnoj industriji i proizvodnji papira, dok su karnauba vosak i guma arabica adhezivi biljnog podrijetla, a svoju primjenu nalaze u prehrambenoj i farmaceutskoj industriji kao zgušnjivači i emulgatori. Na uzorcima prirodnih adheziva provedena su ispitivanja topljivosti u različitim otapalima te su ispitana površinska svojstva mjerenjem kontaktnog kuta na filmovima dobivenim iz otopine adheziva. Strukturna svojstva adheziva ispitana su primjenom FTIR-ATR spektroskopije, a toplinska svojstva primjenom diferencijalne pretražne kalorimetrije (DSC) i termogravimetrijske analize (TGA). Ispitivanja su pokazala značajne razlike između životinjskih i biljnih adheziva. DSC tehnikom utvrđeno je da su goveđe tutkalo i karnauba vosak semikristalne strukture, dok su šelak i guma arabica amorfne strukture. TGA analizom utvrđeno je da se karnauba vosak razgrađuje u jednom stupnju, dok se šelak, goveđe tutkalo i guma arabica razgrađuju u dva ili više stupnja.

Abstract (english)

The term of adhesive has been known since ancient times and the first applicable adhesives were of natural origin, including all plant and animal-based adhesives and natural rubbers. Their affordable price and good quality still enable wide application, especially in wood and food industry where the most valuable worth is their natural origin. In this paper, an overview of natural adhesives of plant and animal origin is given, and the properties of four types of natural adhesives are examined. Shellac and bone glue are animal-based adhesives which are used in wood and paper industries, while carnauba wax and gum arabic are plant-based adhesives which are used in food and pharmaceutical industries as thickeners and emulsifiers. Solubility tests in different solvents were performed on samples of natural adhesives, and surface properties were examined by measuring the contact angle on films obtained from the adhesive solution. The structural properties were examined by using FTIR-ATR spectroscopy, and thermal properties by using differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). The results have shown significant differences between animal and plant-based adhesives. The DSC method determined that bone glue and carnauba wax have semicrystalline structure, while shellac and gum arabic have amorphous structure. TGA analysis found that carnauba wax decomposes in one stage, while shellac, bone glue and gum arabic decompose in two or more stages.

• Keywords: prirodni adhezivi; topljivost; kontaktni kut; staklište; toplinska svojstva
• Keywords (english): natural adhesives; solubility; contact angle; glass transition temperature; thermal properties
• Language: croatian
• URN:NBN: urn:nbn:hr:149:389681
• Study programme: Title: Applied Chemistry - Undergraduate study; specializations in: Environmental chemistry and green technologies, Advanced materials and technologies, Applied organic chemistry; Course: Advanced materials and technologies; Study programme type: university; Study level: undergraduate; Academic / professional title: sveučilišni/a prvostupnik/prvostupnica (baccalaureus/baccalaurea) primijenjene kemije (sveučilišni/a prvostupnik/prvostupnica (baccalaureus/baccalaurea) primijenjene kemije)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2023-05-08 08:01:13