b**s 发帖数: 589 | 1 Finally, certain rheological measurements can often reveal the presence or
absence of block copolymer structures. For example, the melt viscosity of
block copolymers is usually considerably higher than that of a blend of
homopolymers of similar molecular weight. This is especially true for A-B-A
and -(A-B)n- structures due to the persistence of some degree of physical
network structure even in the melt. This effect is magnified in block
copolymers consisting of segments that are long and tha |
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