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ABA三嵌段热塑性弹性体的性质主要取决于A嵌段的性质,A嵌段构成热塑性聚集区保持弹性网络的整体性。这些聚集区既可以是非晶的也可以是结晶的,前者源于A和B嵌段固有的不相容性,后者是通过通常的结晶过程形成的。可以令人信服地证明:形成的非晶(玻璃)区随着A和B嵌段不相容程度增加而增大,且这种材料的强度取决于相分离程度和非晶区的完整性。然而,粘度随着两相间不相容性增加而上升。这可能是由于甚至在熔体中两相形态依然存在所致。另一方面,熔体不发生相分离的可结晶A嵌段的存在,使流动性良好。不过,材料的强度和其他机械性能强烈地依赖于A嵌段的分子量和结晶性。
The properties of ABA triblock thermoplastic elastomers depend primarily on the nature of the A block, which constitutes the thermoplastic aggregation zone to maintain the integrity of the elastic network. These aggregates can either be amorphous or crystalline, the former stems from the inherent incompatibility of the A and B blocks, which are formed by the usual crystallization processes. It can be convincingly demonstrated that the amorphous (glass) region formed increases as the degree of incompatibility of the A and B blocks increases, and the strength of this material depends on the degree of phase separation and the integrity of the amorphous region. However, viscosity increases with increasing incompatibility between the two phases. This may be due to the fact that the two phases are still present even in the melt. On the other hand, the presence of a crystallizable A block in which the melt does not phase-separate provides good fluidity. However, the strength and other mechanical properties of the material strongly depend on the molecular weight and crystallinity of the A block.