Flexible chain plate characteristics: In carbon chain polymers, the polarity z is small hydrocarbons. The intramolecular interaction is not large, the internal rotation barrier is small, and the polymer chain has greater flexibility, such as polyethylene, polypropylene and so on. The main chain of diene polymers contains double bonds. Although the double bond itself cannot undergo rotation, it makes the internal rotation of Z-adjacent single bonds easier, such as 1, 4-polybutadiene. The barrier of internal rotation around C-O,C-N,Si-O and other single bonds in hetero-chain polymers is smaller than that of C-C single bonds. Therefore, the molecular chains of a series of polymers such as polyester, polyamide, polydimethylsiloxane, and polyurethane are flexible chains.

Flexible chain plate influencing factors: The introduction of polar substituents in polymers will increase the intramolecular interaction, thus affecting the flexibility of polymer chains. The effect depends on the polarity of the substituent, the distance along the molecular chain, and the symmetry. The influence of the non-polar substituents is mainly determined by the size of the substituents. If there is a strong interaction between molecular chains (such as hydrogen bonds), it will also affect its flexibility.