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IDENTIFIKACIJA VLAKANA PRIMENOM MIKRORAMANSKE SPEKTROSKOPIJE

IDENTIFICATION OF FIBERS BY MICRORAMAN SPECTROSCOPY

AUTOR: TAMARA RAKIĆ, učenica II razreda Šeste beogradske gimnazije, Regionalni centar za
talente, Beograd II MENTOR: DrNADA BOŠNJAKOVIĆ PAVLOVIĆ, naučni saradnik, Fakultet za
fizičku hemiju, Univerzitet u Beogradu

REZIME

Ramanska spektroskopija je jedan od najzastupljenijih tipova spektroskopije koji može da se koristi u različite svrhe
(analiza sastava organskih i neorganskih supstanci, identifikacija materijala, pigmenata i dr.). Ovo je relativno nova
tehnika i otkrivena je 1928. godine od strane indijskog fizičara Ramana, po kome je i dobila ime. Cilj ovog
istraživanja je pokazivanje načina identifikacije vlakana pomodu ramanske spektroskopije, kao i isticanje prednosti i
nedostataka ove tehnike. U ovom radu snimani su spektri četiri uzorka vlakana – dva pamučna i dva od poliestera,
koji su kasnije upoređivani sa prethodno snimanim spektrima radi identifikacije. Snimanje je vršeno pomodu lasera
vede talasne dužine kako bi se izbegla fluorescencija, kao i termičko razlaganje uzorka. Utvrđeno je da se spektri
vlakana istog sastava poklapaju uz neznatne razlike koje su dovoljno male da ne bi predstavljale problem pri
identifikaciji. Nepolarne veze se jasno vide na ramanskim spektrima, dok se polarne teže uočavaju. Fluorescencija
je, međutim, bila vidljiva iako se vodilo računa o tome da se ona svede na minimum. Ipak, i pored toga,
identifikacija je bila moguda jer su glavne trake na spektrima, koje nastaju usled posledica sastava uzorka, bile jasno
vidljive.

KLJUČNE REČI: identifikacija vlakana, ramanska spektroskopija, vlakna, fluorescencija

SUMMARY

Raman spectroscopy is one of the most common types of spectroscopy that can be used for multiple purposes
(analysis of the composition of organic and inorganic substances, identification of materials, pigments etc.). This is
a relatively new technique and was discovered in 1928 by the Indian physician Raman, after whom it was named.
The goal of this research is to show the method of fiber identification with the use of Raman spectroscopy, as well
as to highlight the advantages and flaws of this technique. In the research four spectra of four fiber samples were
recorded – two made out of cotton and two out of polyester, which were later compared to previously recorded
spectra for the sake of identification. The recordings were performed with a long wavelength laser to avoid
fluorescence and thermic degradation of the samples. It has been established that the spectra of fibers with the
same composition match, with the presence of slight differences that are small enough not to present a problem in
the identification. Nonpolar bonds are clearly visible on the Raman spectra, while polar bonds are harder to detect.
Fluorescence was, however, visible even though precautions were made so it could be reduced to a minimumEven
after that, the identification was possible because the main bands, which appear due to the consequences of the
sample composition, were still clearly visible on the spectra.

KEY WORDS: identification of fibers, Raman spectroscopy, fibers, fluorescence