Properties of water-blown rigid polyurethane foams with reactivity of raw materials

2004 ◽  
Vol 93 (5) ◽  
pp. 2334-2342 ◽  
Author(s):  
W. J. Seo ◽  
J. H. Park ◽  
Y. T. Sung ◽  
D. H. Hwang ◽  
W. N. Kim ◽  
...  
2020 ◽  
pp. 607-608
Author(s):  
M. Ionescu ◽  
S. Mihai ◽  
E. Stepan ◽  
C. Roibu ◽  
V. Preoteasa

2020 ◽  
Vol 56 (6) ◽  
pp. 630-645 ◽  
Author(s):  
Ibrahim Sendijarevic ◽  
Karol W Pietrzyk ◽  
Christi M. Schiffman ◽  
Vahid Sendijarevic ◽  
Alper Kiziltas ◽  
...  

The objective of this study was to produce a polyol from spent coffee grounds via acid liquification process that meets performance requirements for use in polyurethane applications. The spent coffee grounds based polyol was characterized and evaluated on a fully catalyzed model rigid polyurethane foam system. The pH of the polyol was 6.8, acid value 4.12 mg KOH/g, and hydroxyl value 302.6 mg KOH/g, which are in the range of polyols used in rigid polyurethane foams. The reactivity study confirmed enhanced reactivity of the spent coffee grounds polyol compared to standard sucrose-glycerol initiated polyether polyols, which can be attributed to higher content of primary reactive hydroxyls. Scanning electron microscopy microphotographs of the foams prepared with 10%, 20%, and 30% spent coffee grounds polyol based on total polyols in the formulation revealed a drained dodecahedron type cell structure with intact cell windows as a clear indication of the closed cell structure typical for the rigid polyurethane foams used in thermal insulation applications. Results of this study confirmed the feasibility to produce polyols from spent coffee grounds with performance characteristics suitable for polyurethane application. The fact that spent coffee grounds are readily available industrial waste generated in instant coffee manufacturing, makes this biomass residue a sustainable source of raw materials for scalable production of polyols for polyurethanes.


2020 ◽  
Vol 22 (1) ◽  
pp. 69
Author(s):  
Joanna Paciorek-Sadowska ◽  
Marcin Borowicz ◽  
Ewelina Chmiel ◽  
Jacek Lubczak

Two polyol raw materials were obtained in the conducted research, one based on metasilicic acid (MSA), the other based on poly(lactic acid) (PLA) waste. The obtained polyols were characterized in terms of their applicability for the production of rigid polyurethane foams (RPUFs). Their basic analytical properties (hydroxyl number, acid number, elemental analysis) and physicochemical properties (density, viscosity) were determined. The assumed chemical structure of the obtained new compounds was confirmed by performing FTIR and 1H NMR spectroscopic tests. Formulations for the synthesis of RPUFs were developed on the basis of the obtained research results. A mixture of polyols based on MSA and PLA in a weight ratio of 1:1 was used as the polyol component in the polyurethane formulation. The reference foam in these tests was a foam that was synthesized only on the basis of MSA-polyol. The obtained RPUFs were tested for basic functional properties (apparent density, compressive strength, water absorption, thermal conductivity coefficient etc.). Susceptibility to biodegradation in soil environment was also tested. It was found that the use of mixture of polyols based on MSA and PLA positively affected the properties of the obtained foam. The polyurethane foam based on this polyol mixture showed good thermal resistance and significantly reduced flammability in comparison with the foam based MSA-polyol. Moreover, it showed higher compressive strength, lower thermal conductivity and biodegradability in soil. The results of the conducted tests confirmed that the new foam was characterized by very good performance properties. In addition, this research provides information on new waste management opportunities and fits into the doctrine of sustainable resource management offered by the circular economy.


Materials ◽  
2021 ◽  
Vol 14 (7) ◽  
pp. 1772
Author(s):  
Milena Leszczyńska ◽  
Elżbieta Malewska ◽  
Joanna Ryszkowska ◽  
Maria Kurańska ◽  
Michał Gloc ◽  
...  

The reported study concerns the introduction of renewable raw materials into the formulation of rigid polyurethane foams in the quest for the sustainable development of polymer composites. In this study, rigid polyurethane foam composites were prepared using 75 wt.% of rapeseed oil-based polyol and 15 parts per hundred parts of polyol (php) of natural fillers such as chokeberry pomace, raspberry seeds, as well as hazelnut and walnut shells. The influence of the used raw materials on the foaming process, structure, and properties of foams was investigated using a FOAMAT analyzer and a wide selection of characterization techniques. The introduction of renewable raw materials limited reactivity of the system, which reduced maximum temperature of the foaming process. Moreover, foams prepared using renewable raw materials were characterized by a more regular cell structure, a higher share of closed cells, lower apparent density, lower compressive strength and glass transition temperature, low friability (<2%), low water absorption (<1%), high dimensional stability (<±0.5%) and increased thermal stability. The proper selection and preparation of the renewable raw materials and the rational development of the polyurethane recipe composition allow for the preparation of environmentally-friendly foam products with beneficial application properties considering the demands of the circular economy in the synthesis of rigid foams.


2020 ◽  
Vol 17 (10) ◽  
pp. 760-771
Author(s):  
Qirui Gong ◽  
Niangui Wang ◽  
Kaibo Zhang ◽  
Shizhao Huang ◽  
Yuhan Wang

A phosphaphenanthrene groups containing soybean oil based polyol (DSBP) was synthesized by epoxidized soybean oil (ESO) and 9,10-dihydro-oxa-10-phosphaphenanthrene-10-oxide (DOPO). Soybean oil based polyol (HSBP) was synthesized by ESO and H2O. The chemical structure of DSBP and HSBP were characterized with FT-IR and 1H NMR. The corresponding rigid polyurethane foams (RPUFs) were prepared by mixing DSBP with HSBP. The results revealed apparent density and compression strength of RPUFs decreased with increasing the DSBP content. The cell structure of RPUFs was examined by scanning electron microscope (SEM) which displayed the cells as spherical or polyhedral. The thermal degradation and flame retardancy of RPUFs were investigated by thermogravimetric analysis, limiting oxygen index (LOI), and UL 94 vertical burning test. The degradation activation energy (Ea) of first degradation stage reduced from 80.05 kJ/mol to 37.84 kJ/mol with 80 wt% DSBP. The RUPF with 80 wt% DSBP achieved UL94 V-0 rating and LOI 28.3. The results showed that the flame retardant effect was mainly in both gas phase and condensed phase.


Materials ◽  
2021 ◽  
Vol 14 (13) ◽  
pp. 3474
Author(s):  
Katarzyna Uram ◽  
Milena Leszczyńska ◽  
Aleksander Prociak ◽  
Anna Czajka ◽  
Michał Gloc ◽  
...  

Rigid polyurethane foams were obtained using two types of renewable raw materials: bio-polyols and a cellulose filler (ARBOCEL® P 4000 X, JRS Rettenmaier, Rosenberg, Germany). A polyurethane system containing 40 wt.% of rapeseed oil-based polyols was modified with the cellulose filler in amounts of 1, 2, and 3 php (per hundred polyols). The cellulose was incorporated into the polyol premix as filler dispersion in a petrochemical polyol made using calenders. The cellulose filler was examined in terms of the degree of crystallinity using the powder X-ray diffraction PXRD -and the presence of bonds by means of the fourier transform infrared spectroscopy FT-IR. It was found that the addition of the cellulose filler increased the number of cells in the foams in both cross-sections—parallel and perpendicular to the direction of the foam growth—while reducing the sizes of those cells. Additionally, the foams had closed cell contents of more than 90% and initial thermal conductivity coefficients of 24.8 mW/m∙K. The insulation materials were dimensionally stable, especially at temperatures close to 0 °C, which qualifies them for use as insulation at low temperatures.


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