main chain in these MJLCPs is significantly more flexible compared to polystyrene
or polyacrylate/polymethacrylate backbones, the polymers still form supramolecular
Col n or smectic LC phases with much narrower temperature ranges of the LC phases.
The MJLCPs possess low contact-angle values because the polysiloxane backbone is
embedded in the side chains, further confirming the mesogen-jacketed model.
Compared to the general method of polymerizing a monomer, this polymer reaction
approach cannot guarantee a 100% reaction efficiency, leading to polymers with
chemical defects. Therefore, highly efficient reactions are always preferred. The
Cu(I)-catalyzed 1,3-dipolar cycloaddition click reaction was utilized to synthesize a
series of comb polymers, poly{2,5-bis[(4-methoxyphenyl)oxycarbonyl]styrene}-gpolystyrene (PMPCS-g-PS), with MJLCP as the side chains from α-yne-terminated
H3C Si
CH3
CH3
O
Si
CH3
O
H
Si
CH3
CH3
CH3
35
+
Pt(dvs) or H2PtCl6
THF, reflux, 2 d
H3C Si
CH3
CH3
O
Si
CH3
O
CH2
Si
CH3
CH3
CH3
35
CH2
Styrenic compound
Si-12C2Vp
C
C
O
O
O
O
OCH3
H3CO
C
C
O
O
O
O
OC4H9
C4H9O
N N
O
O
N N
C12H25O
OC12H25
C
O
O
C4H9O
C
O
O
OC4H9
C
O
O
C12H25O
C
O
O
OC12H25
Synthesis and Structures of the Mesogen-jacketed polysiloxanes
Si-4C2Vp
Si-OXD-C12p
Si-BPCS
Si-MPCS
Scheme 11 Synthesis of the mesogen-jacketed polysiloxanes (Zhang et al. 2010)
52
Z. Shen