Common Chain-Growth Polymers - Principles of Polymer Chemistry - page 342

Table 6.6 Properties of poly( a -olefin)s
Monomer MP ( C) State

Crystalline 136

Crystalline 165-168

Crystalline 124-130

Crystalline 75

Rubber, amorphous -

3

Some crystallinity 45

9

Crystallinity in pendant groups 70; 100

13

Crystalline, hard 240-285

Crystalline, hard 200-240

Crystalline, hard 300-350

Crystalline, hard 350

Crystalline, hard 160

Rubber, amorphous -

Crystalline, slightly rubbery 158

Crystalline, intractable 360

Rubber, amorphous -

a From refs. [ 72 , 83 ]

A number of similar polyolefins with pendant side groups are known. These include poly(3-methyl
butene-1), poly(4,4-dimethyl pentene-1), and poly(vinyl cyclohexane). Due to their increased cohe-
sive energy, ability to pack into tight structures, and the effect of increasing stiffness of the pendant
groups, some of these polymers have a high melting point. This can be seen from Table 6.9 . Many of
these polymers, however, tend to undergo complex morphological changes on standing. This can
result in fissures and planes of weakness in the structure.