In view of the experience I had acquired in the field of chemical industry, certain Italian government and industrial bodies entrusted me in 1938 with the task of instituting research and development studies on the production of synthetic rubber in Italy.
If the polymer chain assumes a helicoidal conformation in the crystalline state, and if it does not contain asymmetric carbon atoms, it can be expected that either helices of the same sense, or, in equal ratio, helices of opposite sense are represented in the lattice.
All vinyl polymers may be regarded as built from monomeric units containing a tertiary carbon atom.
If the chain symmetry is maintained in the crystal lattice, the possible occurrence of different space groups is considerably restricted.
