Tezislər / Theses

THE 3
rd
 INTERNATIONAL SCIENTIFIC CONFERENCES OF STUDENTS AND YOUNG RESEARCHERS 
dedicated to the 99
th
anniversary of the National Leader of Azerbaijan Heydar Aliyev
378
 
Figure 14. 
Analysis of 
documents
detailing the mode of recycle in all languages on the subject of 
polyurethane recycle for 2010–2020 for chemical and thermo-chemical recycling. [2] 
The way that is utilized is Glycolysis is the most environmentally friendly. 
As is seen from Figure 1, in almost half of recycle of polyurethane account 
for glycolysis since it is easy to obtain these conditions at both laboratory 
condition and industrial scale.
In the glycolysis process there are several process design variables, 
such as reaction temperature, reaction time, which small
‐
molecule glycol is 
employed, and which catalyst might be used to speed the process and 
optimize the economics of the recycle product [4].
Figure 2. C
hemistry of glycolysis. The large desirable polyol moiety is substituted with a 
relatively low
‐
molecular
‐
weight glycol molecule [3] 

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THE 3
rd
 INTERNATIONAL SCIENTIFIC CONFERENCES OF STUDENTS AND YOUNG RESEARCHERS 
dedicated to the 99
th
anniversary of the National Leader of Azerbaijan Heydar Aliyev
379
In the synthesis of the recovered polyol, Di propylene glycol, diethylene 
glycol and di-n-butyl amine were introduced into a 1.5-liter four-necked glass 
flask with a nitrogen inlet, magnetic stirrer, and thermocouple with an exterior 
electric heating mantle, reflux condenser, and magnetic stirrer unit. A ratio of 
DPG: DEG of 1:1 by weight was used. The mixture (glycols/catalyst) was stirred 
at 500-550 rpm while gradually raising the bath temperature to 220°C. 
Polyurethane foam was washed with water and then with acetone after 
isolating it from other materials. The foam was cut into small scrap of about 4-
6 cm size using a shredder and then dried in an oven at 105°C for 24 h to 
remove water. After heating the bath to 180°C, the first portion, one-tenth of 
the foam scrap’s total volume, was introduced into the DEG/DPG/catalyst 
mixture. The rest of the foam scrap was added every ten minutes at a rate of 
one-tenth of the total volume as it dissolved at 180°C. The residual mixture was 
stirred for another 30 min at 220°C and then cooled to ambient temperature [3]. 
After experiment is carried out, desired products were obtained whose 
characteristics are checked with the assist of certain equipment and testes.
References 
[1] Applications and the uses of the polyurethanes. (Accessed on 2 February 2021), 
https://www.polyurethanes.org/en/where-is-it/ 
[2] B.Godinho, N.Gama, A.Barros-Timmons, A.Ferreira (September 2021). Recycling of 
different types of polyurethane foam wastes via acidolysis to produce polyurethane 
coatings. Journals of Sustainable materials and technologies, 7-11 pages. 
[3] Hiroko Watando, Shioko Saya, Taro Fukaya, Shinetsu Fujieda, Masaaki Yamamoto, 
(2006), Improving chemical recycling rate by reclaiming polyurethane elastomer from 
polyurethane foam, Journals of Sustainable materials and technologies, 6-12 pages. 
[4] T. Thomson (2018), Polyurethane Immobilization of Cells and Biomolecules: Medical and 
Environmental Applications. Wiley, 121 pp. 
[5] John O. Akindoyo, M. D. H. Beg, Suriati Ghazali, M. R. Islam, Nitthiyah Jeyaratnam, A.R. 
Yuvaraj, “Polyurethane Types, Synthesis And Applications”, 2016.