Polyquinolines crystalline

PROPERTIES OF SPECIAL INTEREST The Structure of polyquinolines can be altered from a semirigid chain to a rigid one during the synthesis. Although largely an amorphous polymer, some substituted rigid-rod members exhibit crystallinity in low amounts. Polyquinolines are found to posses excellent thermal and oxidative stability, good mechanical properties, low dielectric constants, low values of moisture absorption, and low thermal expansion coefficients. 

Polyquinolines having directly bonded quinoline units in the 6-positions and connected in the 2-positions by -phenylene units (eg. 5) are rigid rods that are highly crystalline, having crystalline transition temperatures at 500 C or above.These polymers are soluble only in the polymerization medium... 

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