TY - JOUR
T1 - Design and synthesis of bio-inspired polyurethane films with high performance
AU - Briz-López, Eva Marina
AU - Navarro, Rodrigo
AU - Martínez-Hernández, Héctor
AU - Téllez-Jurado, Lucía
AU - Marcos-Fernández, Ángel
N1 - Publisher Copyright:
© 2020 by the authors. Licensee MDPI, Basel, Switzerland.
PY - 2020/11/2
Y1 - 2020/11/2
N2 - In the present work, the synthesis of segmented polyurethanes functionalized with catechol moieties within the hard or the soft segment is presented. For this purpose, a synthetic route of a new catechol diol was designed. The direct insertion of this catechol-free derivative into the rigid phase led to segmented polyurethanes with low performance (σmax ≈ 4.5 MPa). Nevertheless, when the derivative was formally located within the soft segment, the mechanical properties of the corresponding functionalized polyurethane improved considerably (σmax ≈ 16.3 MPa), owing to a significant increase in the degree of polymerization. It is proposed that this difference in reactivity could probably be attributed to a hampering effect of this catecholic ring during the polyaddition reaction. To corroborate this hypothesis, a protection of the aromatic ring was carried out, blocking the hampering effect and avoiding secondary reactions. The polyurethane bearing the protected catechol showed the highest molecular weight and the highest stress at break described to date (σmax ≈ 66.1 MPa) for these kind of catechol-functionalized polyurethanes. Therefore, this new approach allows for the obtention of high-performance polyurethane films and can be applied in different sectors, benefiting from the molecular adhesion introduced by the catechol ring.
AB - In the present work, the synthesis of segmented polyurethanes functionalized with catechol moieties within the hard or the soft segment is presented. For this purpose, a synthetic route of a new catechol diol was designed. The direct insertion of this catechol-free derivative into the rigid phase led to segmented polyurethanes with low performance (σmax ≈ 4.5 MPa). Nevertheless, when the derivative was formally located within the soft segment, the mechanical properties of the corresponding functionalized polyurethane improved considerably (σmax ≈ 16.3 MPa), owing to a significant increase in the degree of polymerization. It is proposed that this difference in reactivity could probably be attributed to a hampering effect of this catecholic ring during the polyaddition reaction. To corroborate this hypothesis, a protection of the aromatic ring was carried out, blocking the hampering effect and avoiding secondary reactions. The polyurethane bearing the protected catechol showed the highest molecular weight and the highest stress at break described to date (σmax ≈ 66.1 MPa) for these kind of catechol-functionalized polyurethanes. Therefore, this new approach allows for the obtention of high-performance polyurethane films and can be applied in different sectors, benefiting from the molecular adhesion introduced by the catechol ring.
KW - Catechol moiety
KW - Hampering effect
KW - Hard and soft segment
KW - High molecular weight
KW - High performance polyurethanes
UR - http://www.scopus.com/inward/record.url?scp=85096091788&partnerID=8YFLogxK
U2 - 10.3390/polym12112727
DO - 10.3390/polym12112727
M3 - Artículo
AN - SCOPUS:85096091788
SN - 2073-4360
VL - 12
SP - 1
EP - 17
JO - Polymers
JF - Polymers
IS - 11
M1 - 2727
ER -