Synthesis and properties of novel fluorinated polyurethane
based on fluorinated gemini diol
School of Chemical Engineering, Zhejiang
University of Technology, No. 18 Chaowang
Road, Hangzhou 310032, China
Xiang Shi, School of Chemical Engineering,
Zhejiang University of Technology, No. 18
Chaowang Road, Hangzhou 310032, China.
In the current study, the novel fluorinated polyurethanes (FPUs) that contained the
gemini branched fluoroether side groups on the hard segments were developed. In
brief, to obtain these FPUs, a new class of fluorinated gemini diol with double‐
branched fluoroether side groups was first synthesized and characterized by using
Fourier transform infrared spectroscopy, nuclear magnetic resonance, and mass
spectrometry. Subsequently, a series of FPUs were designed and prepared by using
hexamethylene diisocyanate, poly (tetramethylene oxide glycol), 1,4‐butanediol, and
fluorinated gemini diol. Analysis of the FPUs' surface properties from contact angle
analysis indicated that the water contact angle increased from 81° to more than
120° when the content of fluorinated gemini diol was increased. Differential scanning
calorimetry results revealed that introduction of fluorinated gemini dio decreased the
of FPUs, causing a better phase separation. Results from thermogravimetric analysis
studies indicated the thermal stability of FPUs was improved. Scanning electron
microscopy and energy dispersive X‐ray spectroscopy revealed that fluoroether
groups migrate to and enrich on the outmost surface of FPUs.
fluorinated diol, fluorinated polyurethane, surface properties, thermal properties
Polyurethanes, which contain a repeated urethane linkage and have
alternating hard and soft segments, exhibit a typical 2‐phase micro-
structure. They have been extensively applied in different fields, which
can be ascribed to their favorable mechanical properties, such as abra-
sion resistance, toughness, and tensile strength.
surface properties have greatly restricted their application in high‐
performance areas, especially in antifouling and waterproof ones.
Notably, fluorinated polyurethanes (FPUs) can not only possess the
above favorable properties of polyurethanes but are also noted for
some attractive features, such as low water absorption, high thermal
stability, and excellent weatherability. This has promoted the rapid
evolution of FPUs during the past few years.
The general strategies of incorporating fluorocarbon chains into
polyurethanes have highlighted the use of fluorine‐containing chain
and fluorinated macromolecular glycol,
the tailorable molecular structure of polyurethanes. Alternatively,
forming polyurethane‐acrylate polymer by using fluorine‐containing
acrylate and vinyl‐terminated polyurethane can also block fluorine
chemically into the polyurethane main chain.
Generally, the above
methods have contributed to embedding the fluorine‐containing
fragments into polyurethane macromolecules. Notably, such low‐
surface‐tension groups can naturally migrate onto the film surface dur-
ing film formation. As is shown in previous studies, fluorine enrichment
on FPU surface depends on the types of diisocyanate, chain extenders,
and soft segments.
Of them, the hard segments of FPUs with fluo-
rinated side chains may migrate onto the surface because of the low
surface energy of fluorinated moiety. In contrast, the soft segments
will migrate onto the surface due to their low glass transition temper-
ature. Additionally, the competitive rate of migration is dependent on
the phase separation of polyurethane.
To the best of our knowledge, almost no research involving FPUs
based on fluorinated gemini diol has been reported so far, which is
related to the difficulties in synthesizing the fluorinated gemini com-
pound. Comparatively, the gemini fluorinated diol, which contains 2
Received: 3 December 2017 Revised: 11 January 2018 Accepted: 27 February 2018
Polym Adv Technol. 2018;29:1939–1952. Copyright © 2018 John Wiley & Sons, Ltd.wileyonlinelibrary.com/journal/pat 1939