Relaxation in Block Copolymer Interfacial Regions

Triblock and diblock copolymer systems have been studied using differential scanning calorimetry and dielectric spectroscopy. These systems are micro-phase-separated and show glass transitions at -20 degrees C and 90 degrees C which are due to hydrogenated butadiene and styrene microphase, respectively. The lower transition is sharp and well-defined. The upper transition is greatly depressed and has a tail on the low temperature side indicating that motion of some of the styrene segments is greatly affected by interactions with butadiene segments.