Table 9 Chemical composition, phase transition temperatures, and the decomposition residue of
the 2,6-bis[vanillylidene] cyclohexanone-based liquid crystalline polyphosphates (Sakthivel and
Kannan 2004, 2005)
X
m
T m (
C)
a
T i (
C)
a
LC texture
Residue (wt%)
b
–C 2 H 5
6
112
149
Grainy
38
8
98
120
Grainy
35
10
70
102
Nematic Schlieren
34
–C 3 H 7
6
90
125
Grainy
32
8
80
118
Grainy
30
10
68
93
Nematic Schlieren
28
–C 6 H 5
6
140
225
Nematic Schlieren
43
8
115
220
Nematic Schlieren
41
10
110
190
Nematic Schlieren
40
6
97
123
Grainy
34
8
94
118
Nematic Schlieren
32
10
84
103
Nematic Schlieren
31
6
131
154
Grainy
39
8
108
129
Nematic Schlieren
37
10
96
116
Nematic Schlieren
36
T m melting temperature, T i isotropic temperature, LC liquid crystalline
a Peak temperatures from DSC were taken as the phase transition temperature
b
Residue at 600
C were detected by TGA at a heating rate of 20
C min
À1 under nitrogen
atmosphere
Scheme 12 Cross-linking reaction (2π + 2π cyclo-addition) of the 2,6-bis[vanillylidene]
cyclohexanone-based liquid crystalline polyphosphates (Sakthivel and Kannan 2004, 2005)
20 Highly Flame-Retardant Liquid Crystalline Polymers
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