The use of photoinitiated free-radical cyclopolymerization in the preparation of novel side-chain liquid-crystalline polydienes

The technique of photoinitiated free-radical cyclopolymerization has been used to produce a variety of novel side-chain liquid-crystalline (SCLC) polymers in which an alicyclic ring structure is incorporated into a polymer backbone. Most of the SCLC polymers gave glass transition temperatures (T_g) around room temperature and clearing points around 60–70°C. However, the poly(1,5-hexadiene) was the exception to this, exhibiting a T_g value of 14.5°C and a clearing point of 132.5°C. Confirmation of the structure of the alicyclic ring along the polymer backbone is extremely difficult to obtain, but evidence is given in the paper to support the ring structure.