378
the hydrosilylation of Si-H functionalized PSt with allyl cyanide, as well as
trialkoxysilyl- functionalized polymers, using Pt 2 [(ViSiMe 2 ) 2 O] 3 as a catalyst (Quirk
et al. 2008). Butadiene-St rubber was crosslinked with 1,1,5,5-tetramethyl-3,3diphenyltrisiloxane using also CPA as a catalyst. The vulcanizates obtained showed
greater elasticity, good dynamic properties and increased resistance (Doncov 1978).
Olefinic bond-end poly(styrene-b-isobutylene) was grafted onto D
H 6 , by hydrosilylation with Pt catalyst at 150–180 °C. Multiarm (5 or 18) star copolymers were
obained, depending on the stoichiometry Si-H/C=C (1.1–1.2 or 2–4, respectively)
(Shim et al. 1998). The well-defined octa-PIB-arm radial star polymers with polysiloxane cores (octa(PIB-dimethylsiloxy)octasilsesquioxane), composed of eight PIB
arms bound to Q 8 M
H 8 , were prepared from allyl-end PIB by means of hydrosilylation reaction with Q 8 M
H 8 in the presence of the catalyst Pt 2 [(ViSiMe 2 ) 2 O] 3 at RT
(Majoros et al. 1997).
By the hydrosilylation of polydienes with PDMS-co-PMHS or M
H 2 D n using
[Pt(R 2 S) 2 Cl 2 ] as a catalyst were prepared thermoplastic elastomers based on 3D
clusters through hydrogen bonding (Schadebrodt et al. 1999).
PMHS with different linear statistical structures were applied for the modification of properties of chosen elastomers having carbon-chains:
1. Hydrogenated butadiene-St rubber (HNBR) (Bik et al. 2003),
2. Butadiene-acrylonitryl rubber (NBR) (Chruściel et al. 2006),
3. St-butadiene rubber (SBR) (Bieliński et al. 2007a, b).
The chemical modification of organic elastomers with PMHS occurred through
many radical reactions. A profitable effect of the PMHS on some properties of modified elastomers was observed, e.g. an improvement of their tribological properties
and flame resistance (Bik et al., 2003; Chruściel et al. 2006; Bieliński et al. 2007a,
b). HNBR was modified with Me 3 SiO(Me 2 SiO) 22 (MeH SiO) 10 SiMe 3 (M w = 8,220 g/
mol, M n = 3,620 g/mol, PDI = 2.38). A qualitative addition of PMHS to HNBR was
made by Bik et al. (2003). The improvement of the TS, a slight increase of the
E b and rigidity for vulcanized HNBR- polysiloxane elastomer were observed. The
improvement of tribological properties was also noticed: a decrease of the friction
coefficient between crosslinked HNBR and metal surface was found. By modifying
HNBR with 12 wt.% of PMHS, the friction coefficient of the crosslinked vulcanizate using dicumyl peroxide (DCP) did not depend on a force of the normal loading
(Bik et al. 2003).
For the modification of surface properties of NBR were used the following
PDMS-co-PMHS copolymers containing Si-H or Si-CH=CH 2 as functional groups:
Me SiO Me SiO MeHSiO OSiMe
3
2
x
y
3
(
)(
)
,
J. J. Chruściel
the hydrosilylation of Si-H functionalized PSt with allyl cyanide, as well as
trialkoxysilyl- functionalized polymers, using Pt 2 [(ViSiMe 2 ) 2 O] 3 as a catalyst (Quirk
et al. 2008). Butadiene-St rubber was crosslinked with 1,1,5,5-tetramethyl-3,3diphenyltrisiloxane using also CPA as a catalyst. The vulcanizates obtained showed
greater elasticity, good dynamic properties and increased resistance (Doncov 1978).
Olefinic bond-end poly(styrene-b-isobutylene) was grafted onto D
H 6 , by hydrosilylation with Pt catalyst at 150–180 °C. Multiarm (5 or 18) star copolymers were
obained, depending on the stoichiometry Si-H/C=C (1.1–1.2 or 2–4, respectively)
(Shim et al. 1998). The well-defined octa-PIB-arm radial star polymers with polysiloxane cores (octa(PIB-dimethylsiloxy)octasilsesquioxane), composed of eight PIB
arms bound to Q 8 M
H 8 , were prepared from allyl-end PIB by means of hydrosilylation reaction with Q 8 M
H 8 in the presence of the catalyst Pt 2 [(ViSiMe 2 ) 2 O] 3 at RT
(Majoros et al. 1997).
By the hydrosilylation of polydienes with PDMS-co-PMHS or M
H 2 D n using
[Pt(R 2 S) 2 Cl 2 ] as a catalyst were prepared thermoplastic elastomers based on 3D
clusters through hydrogen bonding (Schadebrodt et al. 1999).
PMHS with different linear statistical structures were applied for the modification of properties of chosen elastomers having carbon-chains:
1. Hydrogenated butadiene-St rubber (HNBR) (Bik et al. 2003),
2. Butadiene-acrylonitryl rubber (NBR) (Chruściel et al. 2006),
3. St-butadiene rubber (SBR) (Bieliński et al. 2007a, b).
The chemical modification of organic elastomers with PMHS occurred through
many radical reactions. A profitable effect of the PMHS on some properties of modified elastomers was observed, e.g. an improvement of their tribological properties
and flame resistance (Bik et al., 2003; Chruściel et al. 2006; Bieliński et al. 2007a,
b). HNBR was modified with Me 3 SiO(Me 2 SiO) 22 (MeH SiO) 10 SiMe 3 (M w = 8,220 g/
mol, M n = 3,620 g/mol, PDI = 2.38). A qualitative addition of PMHS to HNBR was
made by Bik et al. (2003). The improvement of the TS, a slight increase of the
E b and rigidity for vulcanized HNBR- polysiloxane elastomer were observed. The
improvement of tribological properties was also noticed: a decrease of the friction
coefficient between crosslinked HNBR and metal surface was found. By modifying
HNBR with 12 wt.% of PMHS, the friction coefficient of the crosslinked vulcanizate using dicumyl peroxide (DCP) did not depend on a force of the normal loading
(Bik et al. 2003).
For the modification of surface properties of NBR were used the following
PDMS-co-PMHS copolymers containing Si-H or Si-CH=CH 2 as functional groups:
Me SiO Me SiO MeHSiO OSiMe
3
2
x
y
3
(
)(
)
,
J. J. Chruściel