371
Poly(tetramethyl-m-silphenylenesiloxane) elastomers were prepared by polycondensation of appropriate bis-silanediols (obtained by hydrolysis of H-silane precursors), at high-vacuum in a final step. The M n , PDI and T g values were 126,000 g/
mol, 2.06 and − 52 °C, respectively. Their surface properties were very similar to
those for PDMS, thus exhibiting very good thermal properties under nitrogen or air
atmosphere (Zhang et al. 1997). High MW poly(silphenylenesiloxane) homopolymers and copolymers were obtained in high yields by the dehydrocondensation of
appropriate bissilanes and disilanols with [(Ph 3 P) 3 RhCl] (Zhang et al. 2000).
Oligosilarylenesiloxane-α,ω-diols (H(Me 2 SiC 6 H 4 SiMe 2 OMe 2 SiC 6 H 4 SiMe 2 O)
n H, n = 2, 4, 6 and 8) were prepared in the presence of RhCl(PPh 3 ) 3 as a catalyst via
dehydrocondensation
of
HMe 2 SiC 6 H 4 SiMe 2 H
with
an
excess
of
1,4-bis(hydroxydimethylsilyl)benzene (HOMe 2 SiC 6 H 4 SiMe 2 OH). They were oxidatively stable and retained elasticity up to 250 °C (Homrighausen and Keller 2002).
New 3,3,3-trifluoropropyl-substituted copoly(carbosiloxane)s were synthesized
by the hydrosilylation of different α,ω-divinylsilanes and siloxanes with
1,9-dihydro- 1,1,3,5,7,9,9-heptamethyl-3,5,7-tris(3,3,3-trifluoropropyl)pentasiloxane (Grunlan et al. 2003). Hydrophobic membranes of different thicknesses
75–195 μm, useful for gas sensors were prepared from a poly(vinylmethylsiloxane)
(M w ≈ 40,000 g/mol), which was crosslinked with PMHS using the Pt catalyst.
Ceramic membranes were modified with perfluoroalkylsilanes: C 6 F 13 C 2 H 4 Si(OEt) 3
(C6) and C 12 F 25 C 2 H 4 Si(OEt) 3 (C12). The membrane modified by C12 was more
hydrophobic (contact angle = 148°), compared to the membrane modified by C6
(contact angle = 135°). A water transport through PDMS membranes was inversely
proportional to membrane thickness (Rozicka et al. 2012).
Polyaddition of dicyclopentadiene into MD
H n M (n ≈ 30 and 53) or MD m D
H n M
(m ≈ 23, n ≈ 33), in the presence of CPA as a catalyst, gave thermoreactive polysiloxanes containing tricyclodecenyl moieties, which can be used for the manufacture
of the silicone elastomers and for the modification of organic elastomers (Mukbaniani
et al. 2007c).
Vinyl-POSS oligomers were used as fillers for end α,ω-PDMS diols and provided considerable reinforcement of the PDMS matrix (Pan et al. 2003). Novel
elastomeric NCs containing POSS as the crosslinker and filler within the PDMS
matrix were prepared by the hydrosilylation of Q 8 M
H 8 (OS-POSS) with telechelic
vinyl-PDMS. The PDMS NCs prepared with the octavinyl OS-POSS crosslinker
showed increased mechanical properties with respect to NCs crosslinked with
Si(OSiMe 2 H) 4 at a similar content, due to the greater volume-fraction of POSS filler
into the polymer matrix (Baumann et al. 2009).
By the dehydrocondensation or polyaddition reactions of D
H 5 with silanol- or
vinyl- end-capped oligodimetylsiloxanes were obtained materials from rigid glasses
to elastic gums (Nugay et al. 2005). Novel tricomponent amphiphilic membranes
consisting of hydrophilic poly(ethylene glycol) (PEG) and hydrophobic PDMS segments were synthesized from diallyl-telechelic and divinyl-terminated PDMS by
cocrosslinking (via hydrosilylation and hydrolytic condensation reactions) with D
H 5
and Q 8 M
H 8 , in the presence of water, using Pt 2 [(ViSiMe 2 ) 2 O] 3 as a catalyst and Et 3 N
as a cocatalyst. The POSS acted as a reinforcing filler and was covalently linked into
14 Hydrosilyl-Functional Polysiloxanes: Synthesis Reactions and Applications
Poly(tetramethyl-m-silphenylenesiloxane) elastomers were prepared by polycondensation of appropriate bis-silanediols (obtained by hydrolysis of H-silane precursors), at high-vacuum in a final step. The M n , PDI and T g values were 126,000 g/
mol, 2.06 and − 52 °C, respectively. Their surface properties were very similar to
those for PDMS, thus exhibiting very good thermal properties under nitrogen or air
atmosphere (Zhang et al. 1997). High MW poly(silphenylenesiloxane) homopolymers and copolymers were obtained in high yields by the dehydrocondensation of
appropriate bissilanes and disilanols with [(Ph 3 P) 3 RhCl] (Zhang et al. 2000).
Oligosilarylenesiloxane-α,ω-diols (H(Me 2 SiC 6 H 4 SiMe 2 OMe 2 SiC 6 H 4 SiMe 2 O)
n H, n = 2, 4, 6 and 8) were prepared in the presence of RhCl(PPh 3 ) 3 as a catalyst via
dehydrocondensation
of
HMe 2 SiC 6 H 4 SiMe 2 H
with
an
excess
of
1,4-bis(hydroxydimethylsilyl)benzene (HOMe 2 SiC 6 H 4 SiMe 2 OH). They were oxidatively stable and retained elasticity up to 250 °C (Homrighausen and Keller 2002).
New 3,3,3-trifluoropropyl-substituted copoly(carbosiloxane)s were synthesized
by the hydrosilylation of different α,ω-divinylsilanes and siloxanes with
1,9-dihydro- 1,1,3,5,7,9,9-heptamethyl-3,5,7-tris(3,3,3-trifluoropropyl)pentasiloxane (Grunlan et al. 2003). Hydrophobic membranes of different thicknesses
75–195 μm, useful for gas sensors were prepared from a poly(vinylmethylsiloxane)
(M w ≈ 40,000 g/mol), which was crosslinked with PMHS using the Pt catalyst.
Ceramic membranes were modified with perfluoroalkylsilanes: C 6 F 13 C 2 H 4 Si(OEt) 3
(C6) and C 12 F 25 C 2 H 4 Si(OEt) 3 (C12). The membrane modified by C12 was more
hydrophobic (contact angle = 148°), compared to the membrane modified by C6
(contact angle = 135°). A water transport through PDMS membranes was inversely
proportional to membrane thickness (Rozicka et al. 2012).
Polyaddition of dicyclopentadiene into MD
H n M (n ≈ 30 and 53) or MD m D
H n M
(m ≈ 23, n ≈ 33), in the presence of CPA as a catalyst, gave thermoreactive polysiloxanes containing tricyclodecenyl moieties, which can be used for the manufacture
of the silicone elastomers and for the modification of organic elastomers (Mukbaniani
et al. 2007c).
Vinyl-POSS oligomers were used as fillers for end α,ω-PDMS diols and provided considerable reinforcement of the PDMS matrix (Pan et al. 2003). Novel
elastomeric NCs containing POSS as the crosslinker and filler within the PDMS
matrix were prepared by the hydrosilylation of Q 8 M
H 8 (OS-POSS) with telechelic
vinyl-PDMS. The PDMS NCs prepared with the octavinyl OS-POSS crosslinker
showed increased mechanical properties with respect to NCs crosslinked with
Si(OSiMe 2 H) 4 at a similar content, due to the greater volume-fraction of POSS filler
into the polymer matrix (Baumann et al. 2009).
By the dehydrocondensation or polyaddition reactions of D
H 5 with silanol- or
vinyl- end-capped oligodimetylsiloxanes were obtained materials from rigid glasses
to elastic gums (Nugay et al. 2005). Novel tricomponent amphiphilic membranes
consisting of hydrophilic poly(ethylene glycol) (PEG) and hydrophobic PDMS segments were synthesized from diallyl-telechelic and divinyl-terminated PDMS by
cocrosslinking (via hydrosilylation and hydrolytic condensation reactions) with D
H 5
and Q 8 M
H 8 , in the presence of water, using Pt 2 [(ViSiMe 2 ) 2 O] 3 as a catalyst and Et 3 N
as a cocatalyst. The POSS acted as a reinforcing filler and was covalently linked into
14 Hydrosilyl-Functional Polysiloxanes: Synthesis Reactions and Applications