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Journal of Analytical & Bioanalytical Techniques | ISSN: 2155-9872 | Volume 9
World HPLC, Separation Techniques & Pharmacovigilance
World Analytical Chemistry & Mass Spectrometry
18
th
International Conference on
August 29-30, 2018 | Toronto, Canada
&
Separation of parent homopolymers from block copolymers with advanced liquid chromatography
methods
Dusan Berek
Polymer Institute of the Slovak Academy of Science, Slovakia
B
lock copolymers present an important group of materials with numerous applications in science, medicine and technology.
In a block copolymer, at least two chemically distinct polymer chains are connected with a chemical bond. Comprehensive
molecular characterization of block copolymers is an analytical challenge. A special problem makes a determination of the
amount and molar mass of parent homopolymers, which occur in most block copolymers and constitute highly undesired
ballast. Gel permeation (size exclusion) chromatography GPC/SEC is commonly employed for the characterization of block
copolymers. Molar mass of a precursor, the block polymerized as first, is determined by GPC/SEC and the same method serves
for the approximate assessment of total molar mass of the block copolymer under study. Due to its low separation selectivity
and detector sensitivity, GPC/SEC can hardly identify the presence of parent homopolymers and render their molar mass.
We will discuss principles and applications of the new separation methods namely liquid chromatography under limiting
conditions of enthalpic interactions, LC-LC and sequential two-dimensional polymer liquid chromatography, S2D LC to solve
the above tasks. LC-LCmethods are well robust and experimentally feasible. Their separation selectivity is very high and sample
recovery is reasonable. LC-LC can efficiently separate both parent homopolymers from diblock copolymers in one single step.
The separated sample constituents can be one-by-one forwarded into an on-line GPC/SEC column for determination of their
molar mass average and distribution. Parent homopolymers present in the block copolymer at a very low concentration below
1% of can be tracked-down and characterized with help of the S2D LC.
Biography
Dusan Berek is employed at Polymer Institute, Slovak Academy of Sciences in Bratislava. Served as elected member of the Presidium of the Slovak Academy
of Sciences, President of the Slovak Chemical Society, Chairman of the Czecho-Slovak and Slovak National Committee of Chemistry for IUPAC. Corresponding
member of the Central European Academy of Sciences and member of the Learned Society of the Slovak Academy of Sciences. Author or co-author of two
monographs and 300+ scientific papers in extenso published in refereed periodicals, proceedings and chapters of books, as well as 60+ patents (four of them
were licensed) - cited more than 3,000x. Presented over 130 invited plenary, key and main lectures, as well as over 900 regular lectures and poster contributions
on symposia and conferences, as well as during lecturing tours to over fourty countries. Elected "Slovak scientist of the year 1999" and "Slovak innovator of the
year 2002".
dusan.berek@savba.skDusan Berek, J Anal Bioanal Tech 2018, Volume 9
DOI: 10.4172/2155-9872-C1-027