366
Liquid silicone resins containing SiO 4/2 silicate branching units and reactive M
H
groups have been used as reinforcing agents for silicone rubbers (SRs) (Muskus and
Ganicz 2007). M 2 D
H
and H-silsesquioxane Q 8 M
H 8 were functionalized with aminopropyl, (hydroxyl)polyether, polyether, glicydyl and -CH 2 CH 2 Me 2 SiCl pendant
groups by hydrosilylation of alkene derivatives in the presence of siloxyl Rh(I)
complexes (Łęszczak et al. 2007; Pancer et al. 2007). Vinyldiphenylsiloxane resins
which were cured with oligo(methylhydro-co-diphenyl)siloxane resins were shrinkless and showed high transparency (~90%) at the visible range, a high refractive
index (n = 1.58) and excellent thermal stability against yellowing. They can be used
as encapsulants for light-emitting diodes (LEDs) (Kim et al. 2012). A low MW
polymethylphenylhydrosiloxane oil, with a refractive index of 1.45 was used as a
component of vinyl-MQ silicone adhesive for encapsulation of LEDs. These cured
materials showed excellent optical transparency, mechanical and optoelectronic
properties, and a hardness of 48 Shore A, as well as good thermal properties at temperature around 180–250 °C was observed. The thermostability of the cured silicone resins with low MW phenyl silicone crosslinker was higher than that of PMHS
oil crosslinker with higher MW (Li et al. 2017).
By curing of prehydrolyzed MTES solution (in acidic medium) with DBTDL
catalyst and PMHS or PDMS-co-PMHS copolymers, new composite coatings were
prepared at RT. The gelation was carried out in the presence of (3-aminopropyl)
triethoxysilane (APTES) or triethylamine (TEA). The coatings obtained from a 2:1
(w/w) ratio of prehydrolyzed MTES solution with equimolar amounts of PMHS
homopolymer and water, catalyzed with APTES, showed high pencil hardness and
excellent corrosion resistance (Huang et al. 2010).
Poly(methylhydrovinylsiloxane)s, such as MD 350 D
Ph 10 D
Vi 10 D
H 10 M, MD 350 D
Vi 10
D
H 10 M and M
Vi
D
H 3 D 219 M
Vi
, have been crosslinked by the hydrosilylation using
Pt 2 [(ViSiMe 2 ) 2 O] 3 as a catalyst at 150 °C, which provided strong films, especially
useful for the manufacture of airbag coatings (Liao and Nye 1998). New modified
polymeric materials have also been prepared by adding C 60 molecules into PMHS
and further crosslinking (West et al. 1994). The 10–20% solutions of
Me 3 Si(OSiHMe) n (OSiMe 2 ) m OSiMe 3 [n/m = 1: (5–10)] and/or Me 3 Si(OSiHMe) n
OSiMe 3 (n = 5–50) in i-propanol or CCl 4 and 0.4–0.6% β-aminoethylsilane,
α-aminopropyl(methoxy)silane or HSi(OMe) 3 and a catalyst were used for hydrophobization and removal ice from metal surfaces (Giurgiu et al. 1994).
Polysiloxane networks obtained by crosslinking of PMVS with PMHS were further modified by hydrosilylation using Pt 2 [(ViSiMe 2 ) 2 O] 3 as a catalyst with allyl
alcohol or allyl derivatives of hydrofilic substrates: allyl-polyol ethers, allylamine
derivatives of polyols and analogous derivatives from simple sugars. This modification changed the surface properties, increased surface tension and decreased wetting
angle of these materials (Sellinger and Laine 1996a, b; Nennendal et al. 2000).
Carbohydrate- modified silicones, prepared by adding PMHS into allyl derivatives
of mono-, di-, and oligosaccharides (in the presence of PtCp 2 Cl 2 ), were surface
active biocompatible materials (Loos and Stadler 2001). A new polysiloxane with
pendant sugar units (glucosyl-thioureylene groups) has also been prepared by
J. J. Chruściel
Liquid silicone resins containing SiO 4/2 silicate branching units and reactive M
H
groups have been used as reinforcing agents for silicone rubbers (SRs) (Muskus and
Ganicz 2007). M 2 D
H
and H-silsesquioxane Q 8 M
H 8 were functionalized with aminopropyl, (hydroxyl)polyether, polyether, glicydyl and -CH 2 CH 2 Me 2 SiCl pendant
groups by hydrosilylation of alkene derivatives in the presence of siloxyl Rh(I)
complexes (Łęszczak et al. 2007; Pancer et al. 2007). Vinyldiphenylsiloxane resins
which were cured with oligo(methylhydro-co-diphenyl)siloxane resins were shrinkless and showed high transparency (~90%) at the visible range, a high refractive
index (n = 1.58) and excellent thermal stability against yellowing. They can be used
as encapsulants for light-emitting diodes (LEDs) (Kim et al. 2012). A low MW
polymethylphenylhydrosiloxane oil, with a refractive index of 1.45 was used as a
component of vinyl-MQ silicone adhesive for encapsulation of LEDs. These cured
materials showed excellent optical transparency, mechanical and optoelectronic
properties, and a hardness of 48 Shore A, as well as good thermal properties at temperature around 180–250 °C was observed. The thermostability of the cured silicone resins with low MW phenyl silicone crosslinker was higher than that of PMHS
oil crosslinker with higher MW (Li et al. 2017).
By curing of prehydrolyzed MTES solution (in acidic medium) with DBTDL
catalyst and PMHS or PDMS-co-PMHS copolymers, new composite coatings were
prepared at RT. The gelation was carried out in the presence of (3-aminopropyl)
triethoxysilane (APTES) or triethylamine (TEA). The coatings obtained from a 2:1
(w/w) ratio of prehydrolyzed MTES solution with equimolar amounts of PMHS
homopolymer and water, catalyzed with APTES, showed high pencil hardness and
excellent corrosion resistance (Huang et al. 2010).
Poly(methylhydrovinylsiloxane)s, such as MD 350 D
Ph 10 D
Vi 10 D
H 10 M, MD 350 D
Vi 10
D
H 10 M and M
Vi
D
H 3 D 219 M
Vi
, have been crosslinked by the hydrosilylation using
Pt 2 [(ViSiMe 2 ) 2 O] 3 as a catalyst at 150 °C, which provided strong films, especially
useful for the manufacture of airbag coatings (Liao and Nye 1998). New modified
polymeric materials have also been prepared by adding C 60 molecules into PMHS
and further crosslinking (West et al. 1994). The 10–20% solutions of
Me 3 Si(OSiHMe) n (OSiMe 2 ) m OSiMe 3 [n/m = 1: (5–10)] and/or Me 3 Si(OSiHMe) n
OSiMe 3 (n = 5–50) in i-propanol or CCl 4 and 0.4–0.6% β-aminoethylsilane,
α-aminopropyl(methoxy)silane or HSi(OMe) 3 and a catalyst were used for hydrophobization and removal ice from metal surfaces (Giurgiu et al. 1994).
Polysiloxane networks obtained by crosslinking of PMVS with PMHS were further modified by hydrosilylation using Pt 2 [(ViSiMe 2 ) 2 O] 3 as a catalyst with allyl
alcohol or allyl derivatives of hydrofilic substrates: allyl-polyol ethers, allylamine
derivatives of polyols and analogous derivatives from simple sugars. This modification changed the surface properties, increased surface tension and decreased wetting
angle of these materials (Sellinger and Laine 1996a, b; Nennendal et al. 2000).
Carbohydrate- modified silicones, prepared by adding PMHS into allyl derivatives
of mono-, di-, and oligosaccharides (in the presence of PtCp 2 Cl 2 ), were surface
active biocompatible materials (Loos and Stadler 2001). A new polysiloxane with
pendant sugar units (glucosyl-thioureylene groups) has also been prepared by
J. J. Chruściel