Hard Block Length Distribution in Segmented Block Copolymers.

摘要

Further evidence is presented to show that under ideal conditions and at complete conversion under stoichiometric conditions the sequence length distribution of hard block segments is a segmented block copolymer follows the most probable distribution. A two-stage polymerization results in a narrower distribution of hard blocks than a single-stage polymerization of the same stoichiometry when the first reaction of the low molecular weight difunctional monomer is faster than the second reaction (Mu>1). In the two-stage polymerization, at intermediate extents of conversion the hard block segments can be classified into six types, depending on how the segment is capped.