373
a catalyst, − with or without participation of poly(diphenylmethane 4,4′-diisocyanate) (PMDI).
A foaming process was competitive with crosslinking of SFs, which led to a formation of a 3D elastomer network. As blowing agents acted:
• hydrogen formed in the dehydrocoupling reaction of Si-OH and C-OH groups of
polysiloxanes with Si-H groups of the crosslinking agent (br-PMHS),
• and CO 2 formed in reaction of icocyanate (NCO) groups with water.
The SFs prepared were elastic materials of a cellular struture, with densities in
the range 0.30–0.45 g/cm
3
. The SFs containing FRs had slow burning and selfextinguishing properties and a very high limiting oxygen index (LOI) value
(41–45%) (Chruściel et al. 2011c).
14.6.4 Synthesis of Hybrid Inorganic-Organic Copolymers
The Si-H bond in silicones is very often used for further functionalization, e.g. to
modify their properties or link of groups initiating ‘controlled’ radical polymerization of acrylic and vinyl monomers (Nakagawa et al. 1997; Miller et al. 1999; Pyun
et al. 1999).
Styrenic and (meth)acrylic star polymers have been synthesized by atom transfer
radical polymerization (ATRP) from (HMeSiO) 4 core (Matyjaszewski et al. 1999).
In this sense, the difunctional ATRP macroinitiators vere prepared by Matyjaszewski
et al. (1999), by hydrosilylation of linear α,ω-dihydro-PDMS with vinylfunctionalized substrates containing a benzyl chloride moiety. They were used in
the polymerization of vinyl monomers [St, methyl acrylate (MA), n-butyl acrylate
(n-BA), iso-bornyl acrylate]. Alternatively, the hydrosilylation of Si-H end groups
of PDMS with allyl or 3-butenyl-2-bromoisobutyrate resulted in new kinds of the
ATRP macroinitiators, which were used for preparing a PSt-b-PDMS-b-PSt copolymer and other hybrid inorganic-organic copolymers (Nakagawa et al. 1998;
Matyjaszewski and Xia 2001).
By the hydrosilylation of M
H 2 D n with (p-chloromethyl)styrene, allyl- and
(3-butenyl)-2-bromoisobutyrate were obtained mono- and difunctional macroinitiators for polymerization of St and acrylate and methacrylate monomers by the ATRP
method, giving organic-inorganic hybrid ABC triblock copolymers (Miller
and Matyjaszewski 1999b). Similarly, by hydrosilylation D
H 4 with (p-chloromethyl)
styrene was synthesized ATRP multifunctional star initiator for grafting PBA,
PMMA or poly(styrene) (PSt) chains (Matyjaszewski et al. 1999).
A block copolymer (PSt-b-PDMS), terminated with an Si-H group and a
random copolymer (PDMS-r-PMHS) were functionalized with 3-butenyl
2- bromoisobuty rate giving ATRP macroinitiator, which was then copolymerized
with n-BA or methyl methacrylate (MMA), to give well-defined triblock copolymers: PSt-b-PDMS-b-PBA and PSt-b-PDMS-b-PMMA. The PDMS-r-PMHS
14 Hydrosilyl-Functional Polysiloxanes: Synthesis Reactions and Applications
a catalyst, − with or without participation of poly(diphenylmethane 4,4′-diisocyanate) (PMDI).
A foaming process was competitive with crosslinking of SFs, which led to a formation of a 3D elastomer network. As blowing agents acted:
• hydrogen formed in the dehydrocoupling reaction of Si-OH and C-OH groups of
polysiloxanes with Si-H groups of the crosslinking agent (br-PMHS),
• and CO 2 formed in reaction of icocyanate (NCO) groups with water.
The SFs prepared were elastic materials of a cellular struture, with densities in
the range 0.30–0.45 g/cm
3
. The SFs containing FRs had slow burning and selfextinguishing properties and a very high limiting oxygen index (LOI) value
(41–45%) (Chruściel et al. 2011c).
14.6.4 Synthesis of Hybrid Inorganic-Organic Copolymers
The Si-H bond in silicones is very often used for further functionalization, e.g. to
modify their properties or link of groups initiating ‘controlled’ radical polymerization of acrylic and vinyl monomers (Nakagawa et al. 1997; Miller et al. 1999; Pyun
et al. 1999).
Styrenic and (meth)acrylic star polymers have been synthesized by atom transfer
radical polymerization (ATRP) from (HMeSiO) 4 core (Matyjaszewski et al. 1999).
In this sense, the difunctional ATRP macroinitiators vere prepared by Matyjaszewski
et al. (1999), by hydrosilylation of linear α,ω-dihydro-PDMS with vinylfunctionalized substrates containing a benzyl chloride moiety. They were used in
the polymerization of vinyl monomers [St, methyl acrylate (MA), n-butyl acrylate
(n-BA), iso-bornyl acrylate]. Alternatively, the hydrosilylation of Si-H end groups
of PDMS with allyl or 3-butenyl-2-bromoisobutyrate resulted in new kinds of the
ATRP macroinitiators, which were used for preparing a PSt-b-PDMS-b-PSt copolymer and other hybrid inorganic-organic copolymers (Nakagawa et al. 1998;
Matyjaszewski and Xia 2001).
By the hydrosilylation of M
H 2 D n with (p-chloromethyl)styrene, allyl- and
(3-butenyl)-2-bromoisobutyrate were obtained mono- and difunctional macroinitiators for polymerization of St and acrylate and methacrylate monomers by the ATRP
method, giving organic-inorganic hybrid ABC triblock copolymers (Miller
and Matyjaszewski 1999b). Similarly, by hydrosilylation D
H 4 with (p-chloromethyl)
styrene was synthesized ATRP multifunctional star initiator for grafting PBA,
PMMA or poly(styrene) (PSt) chains (Matyjaszewski et al. 1999).
A block copolymer (PSt-b-PDMS), terminated with an Si-H group and a
random copolymer (PDMS-r-PMHS) were functionalized with 3-butenyl
2- bromoisobuty rate giving ATRP macroinitiator, which was then copolymerized
with n-BA or methyl methacrylate (MMA), to give well-defined triblock copolymers: PSt-b-PDMS-b-PBA and PSt-b-PDMS-b-PMMA. The PDMS-r-PMHS
14 Hydrosilyl-Functional Polysiloxanes: Synthesis Reactions and Applications