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Bio-based rigid polyurethane foam from castor oil with excellent flame retardancy and high insulation capacity via cooperation with carbon-based materials

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Pablo Alberto Acuña Domínguez at Centro Tecnológico de Automoción de Galicia
Pablo Alberto Acuña Domínguez
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In this work, we prepared the biomass castor oil-based rigid polyurethane foams (RPUF). The two bio-based RPUFs contain modified polyols from castor oil, one of which was transamidated castor oil with diethanolamine (BIO1) and another was further modified epoxidized polyols in BIO1 with phenylphosphonic acid. The cellular structure, thermal, flame retardant and mechanical properties of RPUF via incorporation of expandable graphite (EG) and graphene oxide (GO) on a total fixed amount of 6 wt% were studied by scanning electron microscopy (SEM), thermal conductivity, limiting oxygen index (LOI), vertical burning test (UL94) and cone calorimeter test (CCT), etc. The cellular structure indicated that GO facilitates the dispersion of EG and decreases the cell size of the foam. The thermal and fire behaviors indicated that GO increased the insulation capacity and the flame-retardant performance of RPUFs. The optimal sample BIO2/EG/GO obtained V-0 rating, whereas BIO2/EG obtained only V-2 rating on the UL94 test. Moreover, results from CCT showed that the BIO2/EG/GO effectively reduced heat release rate (HRR), total heat release (THR) and total smoke production (TSP) by 54%, 24% and 15%, respectively, in comparison with BIO1 and decreased the HRR and THR 46% and 6%, respectively, compared to BIO2 sample. The compressive performance of BIO2/EG/GO and BIO2/EG increased to 0.11 MPa compared to 0.07 MPa from BIO1. These interesting results proved a new strategy to develop a bio-based flame-retardant RPUF as fire safety thermal insulation materials by incorporating natural-based carbon materials. Graphic abstract
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POLYMERS & BIOPOLYMERS
Bio-based rigid polyurethane foam from castor oil
with excellent flame retardancy and high insulation
capacity via cooperation with carbon-based materials
Pablo Acun
˜a
1,2
, Jing Zhang
1,3
, Guang-Zhong Yin
1
, Xue-Qi Liu
4
, and De-Yi Wang
1,
*
1
IMDEA Materials Institute, C/Eric Kandel 2, 28906 Getafe, Madrid, Spain
2
Department of Materials Science and Engineering and Chemical Engineering, Carlos III University, Avda. de la Universidad, 30,
28911 Leganés, Madrid, Spain
3
Universidad Politécnica de Madrid, E.T.S. de Ingenieros de Caminos, 28040 Madrid, Spain
4
The Second Research Institute of Civil Aviation Administration of China, Section 2, South 2nd Ring Road, Chengdu 610041, China
Received: 23 April 2020
Accepted: 14 July 2020
Published online:
23 October 2020
ÓSpringer Science+Business
Media, LLC, part of Springer
Nature 2020
ABSTRACT
In this work, we prepared the biomass castor oil-based rigid polyurethane foams
(RPUF). The two bio-based RPUFs contain modified polyols from castor oil, one
of which was transamidated castor oil with diethanolamine (BIO1) and another
was further modified epoxidized polyols in BIO1 with phenylphosphonic acid.
The cellular structure, thermal, flame retardant and mechanical properties of
RPUF via incorporation of expandable graphite (EG) and graphene oxide (GO) on
a total fixed amount of 6 wt% were studied by scanning electron microscopy
(SEM), thermal conductivity, limiting oxygen index (LOI), vertical burning test
(UL94) and cone calorimeter test (CCT), etc. The cellular structure indicated that
GO facilitates the dispersion of EG and decreases the cell size of the foam. The
thermal and fire behaviors indicated that GO increased the insulation capacity
and the flame-retardant performance of RPUFs. The optimal sample BIO2/EG/
GO obtained V-0 rating, whereas BIO2/EG obtained only V-2 rating on the UL94
test. Moreover, results from CCT showed that the BIO2/EG/GO effectively
reduced heat release rate (HRR), total heat release (THR) and total smoke pro-
duction (TSP) by 54%, 24% and 15%, respectively, in comparison with BIO1 and
decreased the HRR and THR 46% and 6%, respectively, compared to BIO2
sample. The compressive performance of BIO2/EG/GO and BIO2/EG increased
to 0.11 MPa compared to 0.07 MPa from BIO1. These interesting results proved a
new strategy to develop a bio-based flame-retardant RPUF as fire safety thermal
insulation materials by incorporating natural-based carbon materials.
Handling Editor: Maude Jimenez.
Address correspondence to E-mail: deyi.wang@imdea.org
https://doi.org/10.1007/s10853-020-05125-0
J Mater Sci (2021) 56:2684–2701
Polymers & biopolymers
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
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... Many studies have investigated the use or modification of plant-oil-based bio-raw materials to obtain bio-polyols for RPUF [15][16][17][18][19][20][21][22]. P. Acuna et al. [15] reported on the preparation of an RPUF composite using castor oil modified with diethanolamine and phenylphosphonic acid, which resulted in enhanced insulation, mechanical strength, and flame retardancy. However, the thermal conductivity of bio-based RPUF was found to be higher than that of RPUF produced with conventional polyol. ...
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