Reološko ponašanje termoplastičnih poli(estar-siloksana)

Two series of thermoplastic elastomers (TPES), based on poly(dimethylsiloxane) (PDMS) as the soft segment and poly(butylene terephthalate) (PBT) as the hard segment, were analyzed by dynamic mechanical spectroscopy. In the first TPES series the lengths of both hard and soft segments were varied while the mass ratio of the hard to soft segments was nearly constant (about 60 mass%). In the second series, the mass ratio of hard and soft segments was varied in the range from 60/40 to 40/60, with a constant length of soft PDMS segments. The influence of the structure and composition of TPESs on the rheological properties, such as complex dynamic viscosity, μ*, the storage, G', and loss, G', shear modulus as well as the microphase separation transition temperature, TMST, was examined. The obtained results showed that the storage modulus of the TPESs increased in a rubbery plateau region with increase in degree of crystallinity. The rheological measurements of TPESs also showed that a microphase reorganization occurred during the melting process. The microphase separation transition temperatures were in the range from 220 to 234°C. In the isotropic molten state, the complex dynamic viscosity increased with increasing both the content and length of hard PBT segments.Dve serije termoplastičnih elastomera (TPES) na bazi poli(dimetilsiloksana) kao mekog segmenta i poli(butilentereftalata) kao tvrdog segmenta su analizirane dinamičko-mehaničkom spektroskopijom. U prvoj TPES seriji varirane su dužine tvrdih i mekih segmenata dok je njihov maseni odnos bio skoro konstantan (oko 60 mas%). U drugoj seriji, odnos tvrdih i mekih segmenata je variran u opsegu od 60/40 do 40/60, dok je dužina mekih PDMS segmenata bila konstantna. Ispitan je uticaj strukture i sastava TPES kopolimera na reološka svojstva, kao što su kompleksni dinamički viskozitet, μ*, moduli sačuvane, G', i izgubljene energije, G', i temperatura mikrofaznog razdvajanja, TMST. Dobijeni rezultati su pokazali da su uzorci sa većim stepenom kristaliničnosti imali i veće module sačuvane energije u gumolikom platou. Reološka merenja su takođe pokazala da svi TPES uzorci ispoljavaju mikrofaznu reorganizaciju u procesu topljenja. Temperature mikrofaznog razdvajanja su bile u opsegu od 220 do 234°C. U izotropskom rastopu, kompleksni dinamički viskoziteti su rasli sa povećanjem sadržaja i dužine PBT segmenata

Supplementary data for the article: Kodranov, I. D.; Pergal, M. V.; Avdin, V. V.; Manojlović, D. D. Examination of Degradation and Ecotoxicology of Pethoxamid and Metazachlor after Chlorine Dioxide Treatment. Environ Monit Assess 2020, 192 (7), 422. https://doi.org/10.1007/s10661-020-08392-1

Supplementary material for: [https://doi.org/10.1007/s10661-020-08392-1]Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/4007

Poly(urethane-ester-siloxane) networks

The waterproof performance and formation of hydrogen bonds in polyurethane (PU) networks based on Boltorn® hyperbranched polyester of the third pseudo generation (BH-30), α,ω-dihydroxy-(ethylene oxide-poly(dimethylsiloxane)- ethylene oxide) (EO-PDMS-EO) and 4,4’-methylenediphenyl diisocyanate (MDI) were studied in this work. Obtained results revealed that as the content of EOPDMS-EO decreases, the degree of microphase separation increases, while the water resistance of the prepared PU networks decreases.Physical chemistry 2012 : 11th international conference on fundamental and applied aspects of physical chemistry; Belgrade (Serbia); 24-28 September 2012

Supplementary material for the article: Pergal, M. V.; Kodranov, I. D.; Pergal, M. M.; Dojčinović, B. P.; Stanković, D. M.; Petković, B. B.; Manojlović, D. D. Assessment of Degradation of Sulfonylurea Herbicides in Water by Chlorine Dioxide. Water, Air, and Soil Pollution 2018, 229 (9). https://doi.org/10.1007/s11270-018-3947-2

Supplementary material for: [https://doi.org/10.1007/s11270-018-3947-2]Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/2203

Synthesis and swelling behavior of polyurethane networks based on hyperbranched polymer

A series of six polyurethane (PU) networks was synthesized from Boltorn (R) hydroxy-functional hyperbranched polyester (HBP) of the second pseudo generation as a cross-linking agent, alpha,omega-dihydroxy-(ethylene oxide-poly(dimethylsiloxane)-ethylene oxide) (EO-PDMS-EO) and 4,4-methylenediphenyl diisocyanate, by two-step polymerization in solution. Each sample of the prepared PUs had different EO-PDMS-EO content. The chemical structure of the synthesized networks was analyzed by FTIR spectroscopy. The influence of the EO-PDMS-EO content and type of the solvent on the swelling behavior of the PUs in 2-propanol and toluene was investigated. During the swelling measurements, a certain amount of sal fractions was extracted from the PUs by solvents. According to the H-1-NMR results, sal fractions were mainly composed of the soluble hyperbranched PU, formed during the polymerization by partial modification of the end hydroxyl groups of HBP with NCO-terminated prepolymer synthesized in the first step of the reaction. Chains of the so reacted prepolymer can then fold back and form cyclic products by reaction of the free -NCO group from the NCO-terminated prepolymer with free -OH group of HBP. As the EO-PDMS-EO content increases the amount of the sol fractions and swelling degree also increased, indicating that networks with lower EO-PDMS-EO content are more cross-linked and have higher solvent resistance

Novel crosslinked polyurethanes based on hyperbranched polyester

The polyurethane (PU) elastomers based on hydroxy-terminated hyperbranched polyester (BH-20) and 4,4′-methylenediphenyl diisocyanate (MDI) as hard segments and hydroxyl-terminated ethylene oxide-poly(dimethylsiloxane)- ethylene oxide (PDMS-EO) as soft segment, were synthesized and examined in this work. The obtained results show that sol fraction decreases and thermal stability increases with increase of the hard segment content

Supplementary material for the article: Jevtić, S.; Stefanović, A.; Stanković, D. M.; Pergal, M. V.; Ivanović, A. T.; Jokić, A.; Petković, B. B. Boron-Doped Diamond Electrode — A Prestigious Unmodified Carbon Electrode for Simple and Fast Determination of Bentazone in River Water Samples. Diamond and Related Materials 2018, 81, 133–137. https://doi.org/10.1016/j.diamond.2017.12.009

Supplementary material for: [https://doi.org/10.1016/j.diamond.2017.12.009]Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/2081]Related to accepted version: [http://cherry.chem.bg.ac.rs/handle/123456789/3177

Supplementary data for article: Pantelić, M. M.; Zagorac, D. Č. D.; Ćirić, I. Ž.; Pergal, M. V.; Relić, D. J.; Todić, S. R.; Natić, M. M. Phenolic Profiles, Antioxidant Activity and Minerals in Leaves of Different Grapevine Varieties Grown in Serbia. Journal of Food Composition and Analysis 2017, 62, 76–83. https://doi.org/10.1016/j.jfca.2017.05.002

Supplementary material for: [https://doi.org/10.1016/j.jfca.2017.05.002]Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/2505]Related to accepted version: [http://cherry.chem.bg.ac.rs/handle/123456789/3063

Supplementary material for the article: Jevtić, S.; Stefanović, A.; Stanković, D. M.; Pergal, M. V.; Ivanović, A. T.; Jokić, A.; Petković, B. B. Boron-Doped Diamond Electrode — A Prestigious Unmodified Carbon Electrode for Simple and Fast Determination of Bentazone in River Water Samples. Diamond and Related Materials 2018, 81, 133–137. https://doi.org/10.1016/j.diamond.2017.12.009

Supplementary material for: [https://doi.org/10.1016/j.diamond.2017.12.009]Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/2081]Related to accepted version: [http://cherry.chem.bg.ac.rs/handle/123456789/3177

Structural, thermal and surface characterization of thermoplastic polyurethanes based on poly(dimethylsiloxane)

In this study, the synthesis, structure and physical properties of two series of thermoplastic polyurethanes based on hydroxypropyl-terminated poly(dimethylsiloxane) (HP-PDMS) or hydroxyethoxypropyl-terminated poly(dimethylsiloxane) (EO-PDMS) as soft segments, and 4,4'-methylenediphenyl diisocyanate and 1,4-butanediol as hard segments were investigated. The polyurethanes were synthesized by two-step polyaddition in solution. The effects of the type and content of PDMS segments on the structure, thermal and surface properties of copolymers were studied by H-1-, C-13-nuclear magnetic resonance (NMR) spectroscopy and two-dimensional NMR spectroscopies (heteronuclear multiple bond correlation (HMBC) and rotating-frame nuclear Overhauser effect (ROESY)), gel permeation chromatography (GPC), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), wide-angle X-ray scattering (WAXS), scanning electron microscopy (SEM) and water contact angle and water absorption measurements. Thermal properties investigated by DSC indicated that the presence of soft PDMS segments lowers the glass transition and melting temperatures of the hard phase as well as the degree of crystallinity. SEM analysis of the copolymers with a lower soft segment content confirmed the presence of spherulite superstructures, which arise from the crystallization of the hard segments. When compared with polyurethanes prepared from HP-PDMS, the copolymers synthesized from EO-PDMS with the same content of the soft segments had a higher degree of crystallinity, better thermal stability and a less hydrophobic surface. The obtained results showed that the synthesized polyurethanes had good thermal and surface properties, which could be further modified by changing the type or content of the soft segments