Koskin, I. P.

Mostovich, E. A.

Benassi, E.

Kazantsev, M. S.

Naumann, Uwe

Publikationsserver der RWTH Aachen University

Exact First and Second Derivatives by Automatic Differentiation

Electronic archive of Tomsk Polytechnic University

XIX Международная научно-практическая конференция имени профессора Л.П. Кулёва486of carboxyl chemical linkages in backbone main chains. The destruction of carbon-hydrogen chem-ical bond in low-molecular PLLA fibers results in loss of molecular weight after treatment with doses higher than 25 kGy. After the process of degrada-tion in PBS, scaffolds show the same tendency to lose molar mass. As a result, scaffolds degradation after irradiation of pulsed e-beam occurs faster than without modification. In conclusion, pulsed e-beam treatment of PLLA scaffolds has a significant influence on its physical and chemical properties. E-beam irradi-ation leads to the decreasing of molecular weight and could be considered as a potential technology to control degradation rate of nonwoven scaffolds. Furthermore, pseudo-surface erosion after irradia-tion will help to avoid acid autocatalysis phenom-enon.References1. Cairns M.L., Dickson G.R., Orr J.F., et al. // Polymer Degradation and Stability, 2011.– Vol.96.–	№1.–	P.76–83.	2. Kudryavtseva V.L., Bolbasov E.N., Ponomarev D.V., et al. // BioNanoScience, 2017.– P.1–9.ON THE WAY TO HIGHLY EMISSIVE MATERIALS: INCREASING RIGIDITY BY INTRODUCTION OF FURAN MOIETY IN Co-OLIGOMERSI.P. Koskin1,2, E.A. Mostovich1,2, E. Benassi2,3, M.S. Kazantsev1,21Novosibirsk State University Russia2Novosibirsk Institute of Organic Chemistry Russia3School of Science and Technology, Nazarbayev State University KazakhstanLinear co-oligomers combining high lumines-cence efficiency and semiconducting properties are of great interest for organic optoelectronics1. Sin-gle crystals of alternating furan/(BPFB)2 or thio-phene/phenylene (BPTB)3 co-oligomers (Figure 1a) demonstrated a promising combination of high charge mobility and high luminescence efficiency, BPFB outperforming its thiophene analogue. How-ever the nature of these differences was poorly un-derstood.In this study we explored intramolecular factors affecting the optoelectronic properties of furan/ and thiophene/phenylene co-oligomers3. We demon-strated that BPFB exhibits almost twice higher (Fig-ure 1b) torsional rigidity than BPTB solely due to more efficient conjugation. The increase of rigidity of BPFB with respect to BPTB was shown to facili-tate hole, electron and exciton transfers. The higher rigidity of BPFB was also suggested to hinder one of the possible luminescence quenching pathways. Fig. 1.		(a)	structures	of	studied	compounds;	(b)	relaxed	scans	of	the	ground	state PES of BPFB (red circles) and BPTB (blue squares) Секция 7.  Химия и химическая технология на иностранном языке487Therefore, tuning of torsional rigidity greatly im-pacts on emission and charge transport properties, being a very powerful tool on the way to high per-formance emissive organic semiconductors.References1. Zhang, L. et al // ACS Appl. Mater. Interfaces, 2014.– 6.– 5327–5343.2. Kazantsev M.S. et al // RSC Adv., 2016.– 6.– 92325–92329.3. Hotta S. et al // J. Mater. Chem., 2011.– 21.– 1295–1304.4. Koskin I.P. et al // J.Phys.Chem., 2017.– 121.– 23359–23369.CHEMICAL RECYCLING OF POLYMER WASTES BASED ON POLYLACTIDEV.V. Krevsun, K.V. Lazarev, V.U. MaletskyScientific adviser – PhD in Chemistry, Associate Professor T.N. Volgina Linguist – PhD in Philology, Associate Professor E.V. ShvagrukovaNational Research Tomsk Polytechnic University 634050, Russia, Tomsk, 30 Lenin Avenue, vvk78@tpu.ruPlastic recycling is strategically important is-sue in many countries. Russia is not an exception. The 21st century, certainly, can be called the century of plastic, because there is a great number of differ-ent products, which are made from this lightweight, durable, and relatively cheap material. The manu-facture of products based on polymers and capable of decomposition by microorganisms is currently being developed. However, biodegradable plastic is rather expensive. So, the best options are recycling of polymer wastes and reuse of these materials. Ob-taining monomers from polymer wastes is a press-ing challenge nowadays [1].Polylactide (PLA) is the linear aliphatic poly-ester, the monomer of which is lactic acid. It rep-resents thermoplastic, transparent, and colorless polymer. The reasons of its extensive use are such properties as biodegradability and biocompatibility. Polylactide is used for production of different films and covers, for 3D printing and in medicine [2]. The process of obtaining lactide is multistage and en-ergy-intensive, which predetermines the low yield of the product, significant loss of lactide during its purification, the formation of a large amount of waste, the high cost of the polymer. This situation could be improved by the recycling of substandard waste based on PLA. This type of polymer can be easily subjected to recycling, in particular, chemical one [3], where the low-molecular fractions (lactic acid and lactide) are produced as a result of polymer chain destruction.The aim of this work was to obtain lactide by thermocatalytic depolymerization of polymer wastes based on polylactide.The objects of research were commodity poly-lactide and polylactide with inorganic pigments, namely, with Fe2O3 and TiO2. The process of ob-taining raw-lactide was conducted over 30 minutes on the laboratory set up for the vacuum distillation at the temperature of 250 °C and the pressure of 10 mbars in the presence of the catalyst ZnO. The puri-fication of raw-lactide was held twice by the method of recrystallization from ethanol. The identification of the product was carried out by the method of IR-spectroscopy. The effectiveness of the process was evaluated by the yield of raw-lactide and pure lactide and the purity of the monomer was assessed by its melting point.The research showed that polymer blends could be subjected to destruction as easily as commodity polylactide, with the formation of monomer 3,6-di-methyl-1,4-dioxan-2,5-dion (or lactide). The mate-rial balance of the process was compiled (Table 1). It showed that the yield of commodity polylactide Table 1. Influence of polymer blend composition on the yield of raw-lactide (βr–l), gas products (βgp), and pitch (βp)Polymer blend βr–l, % βgp, % βp, %PLA 82.63±8.13 3.97±1.61 13.40±6.52PLA + Fe2O3 66.57±31.79 2.43±2.16 30.99±30.80PLA + TiO2 90.84±10.74 2.44±1.36 6.72±10.43

On the way to highly emissive materials: increasing rigidity by introduction of furan moiety in Co-oligomers

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Exact first and second derivatives by automatic differentiation

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On the way to highly emissive materials: increasing rigidity by introduction of furan moiety in Co-oligomers

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