between PHMS and either exclusively eugenol, i.e., 4-allyl-2-methoxyphenol or
eugenol and vinyltrimethoxysilane mixture (Speier’s catalyst, without solvent,
room temperature). The obtained polymers (with S13 groups in Table 12.1,
R=R 4 = H, R 3 = OH) were tested as additives for anticorrosion epoxy coatings
which, after curing, exhibited improved thermal stability and hydrophobicity. Full
spectroscopic characterization of the products was carried out using FTIR,
1 H, and
13 C NMR. The authors showed that the hydrosilylation reaction proceeded with the
formation of only one, b-addition (anti-Markovnikov) product.
12.4.2.3 Polymers with Fluoroalkyl and Other Fluorine-Containing
Side Groups
Fluoroalkyl-functional polysiloxanes are a class of high-performance materials
which combine unique properties of both polysiloxanes and fluorocarbon polymers.
They can be applied to generate superhydrophobic and icephobic surfaces [52],
coatings resistant to hydrocarbon solvents [53], corrosive acidic and oxidative
environments [54], and antifoaming materials [55].
Hydrosilylation of terminal fluoroalkenes that bear some or no linkers between
the carbon–carbon double bond and fluoroalkyl group can lead to undesired side
products [56]. Successful post-functionalization of siloxane polymers with
long-chain fluoroalkyl [57], fluoroalkylether [24, 58], lithiumsulfonate-terminated
perfluoroether [59], fluoroalkylester [52, 60], fluoroalkylhydroxyl [61, 62] side
groups by hydrosilylation was, however, reported. Since fluorine-containing groups
are unreactive, quite often the second type of organic, reactive side group was
introduced into the modified polymer in the next hydrosilylation process.
Maciejewski et al. [24] functionalized PHMS-DMS copolymers of different
chain lengths and Si–H group contents using hydrosilylation of
1,1,2,2,3,3,4,4-octafluoropentyl allyl ether to yield polymers containing fluoroalkylether side groups (Table 12.1, polymer B-S14). Rhodium siloxide complex [{Rh
(OSiMe 3 ) (cod)} 2 ] or Karstedt’s served as catalysts. FTIR-ATR analysis conducted
in situ during syntheses was used to compare their activity. As judged by the
decrease in the intensity of the IR band at 2180 cm
−1 , reactions in the presence of
the rhodium compound were faster than when Karstedt’s catalyst was applied. In
the former case, the process carried out at 80 °C in toluene resulted in complete
conversion of Si–H groups within 10–15 min, whereas in the latter, still 62% of Si–
H groups remained after this time. Similarly, according to FTIR, all Si–H groups
reacted in the consecutive hydrosilylation of 1,1,2,2,3,3,4,4-octafluoropentyl allyl
ether and either vinyltrimethoxysilane or AGE with fluoroalkylether-modified
PHMS-DMS copolymers catalyzed by rhodium complex [24]. This was corroborated by
1 H NMR spectra of polysiloxanes containing mixed functional groups
(fluoroalkylether and either trimethoxysilyl or glycidoxypropyl) obtained in this
way. No signals corresponding to protons of Si–H (d = 4.8 ppm) or vinyl/allyl
(d = 5.0–6.0 ppm) groups were observed which showed that also alkene derivatives reacted completely. The presence of fluoroalkylether, glycidoxypropyl, or
376
A. Chechelska-Noworyta et al.
eugenol and vinyltrimethoxysilane mixture (Speier’s catalyst, without solvent,
room temperature). The obtained polymers (with S13 groups in Table 12.1,
R=R 4 = H, R 3 = OH) were tested as additives for anticorrosion epoxy coatings
which, after curing, exhibited improved thermal stability and hydrophobicity. Full
spectroscopic characterization of the products was carried out using FTIR,
1 H, and
13 C NMR. The authors showed that the hydrosilylation reaction proceeded with the
formation of only one, b-addition (anti-Markovnikov) product.
12.4.2.3 Polymers with Fluoroalkyl and Other Fluorine-Containing
Side Groups
Fluoroalkyl-functional polysiloxanes are a class of high-performance materials
which combine unique properties of both polysiloxanes and fluorocarbon polymers.
They can be applied to generate superhydrophobic and icephobic surfaces [52],
coatings resistant to hydrocarbon solvents [53], corrosive acidic and oxidative
environments [54], and antifoaming materials [55].
Hydrosilylation of terminal fluoroalkenes that bear some or no linkers between
the carbon–carbon double bond and fluoroalkyl group can lead to undesired side
products [56]. Successful post-functionalization of siloxane polymers with
long-chain fluoroalkyl [57], fluoroalkylether [24, 58], lithiumsulfonate-terminated
perfluoroether [59], fluoroalkylester [52, 60], fluoroalkylhydroxyl [61, 62] side
groups by hydrosilylation was, however, reported. Since fluorine-containing groups
are unreactive, quite often the second type of organic, reactive side group was
introduced into the modified polymer in the next hydrosilylation process.
Maciejewski et al. [24] functionalized PHMS-DMS copolymers of different
chain lengths and Si–H group contents using hydrosilylation of
1,1,2,2,3,3,4,4-octafluoropentyl allyl ether to yield polymers containing fluoroalkylether side groups (Table 12.1, polymer B-S14). Rhodium siloxide complex [{Rh
(OSiMe 3 ) (cod)} 2 ] or Karstedt’s served as catalysts. FTIR-ATR analysis conducted
in situ during syntheses was used to compare their activity. As judged by the
decrease in the intensity of the IR band at 2180 cm
−1 , reactions in the presence of
the rhodium compound were faster than when Karstedt’s catalyst was applied. In
the former case, the process carried out at 80 °C in toluene resulted in complete
conversion of Si–H groups within 10–15 min, whereas in the latter, still 62% of Si–
H groups remained after this time. Similarly, according to FTIR, all Si–H groups
reacted in the consecutive hydrosilylation of 1,1,2,2,3,3,4,4-octafluoropentyl allyl
ether and either vinyltrimethoxysilane or AGE with fluoroalkylether-modified
PHMS-DMS copolymers catalyzed by rhodium complex [24]. This was corroborated by
1 H NMR spectra of polysiloxanes containing mixed functional groups
(fluoroalkylether and either trimethoxysilyl or glycidoxypropyl) obtained in this
way. No signals corresponding to protons of Si–H (d = 4.8 ppm) or vinyl/allyl
(d = 5.0–6.0 ppm) groups were observed which showed that also alkene derivatives reacted completely. The presence of fluoroalkylether, glycidoxypropyl, or
376
A. Chechelska-Noworyta et al.