The polar chlorine group
in neoprene rubber offers more resistance to rotational motion than does the methyl group in natural rubber.
The examples in table 6 show that changing the methyl group of polypropylene to a chlorine group
changes the Tg from -10[degrees]C to 87[degrees]C.
Different amines (Table-1) were introduced to triazine moiety by nucleophilic aromatic substitution (NAS) replacing the chlorine groups
This compound is synthetically derived from pyrethrins and has two extra chlorine groups
(which makes it more stable to light).