聚酰胺-聚醚多嵌段共聚物的组成对结晶行为的影响

THE EFFECT OF COMPOSITION OF POLYAMIDE-POIYETHER MULTIBLOCK COPOLYMERS ON CRYSTALLIZATION BEHAVIOR

研究以尼龙1010为硬段,聚四亚甲基醚为软段的聚酰胺-聚醚多嵌段共聚物的结晶行为。用TEM、DSC和激光小角散射等手段观察了该嵌段共聚物的形态和结构,研究硬软段不同组成对该嵌段共聚物的结晶形态、熔融温度和结晶温度的影响。TEM观察到该共聚物呈现球晶结构,球晶由径向发射的晶片组成,并且每一晶片都有许多分枝存在,随着硬段含量的减少,看不到完整的典型的球晶。DSC扫描表明共聚物的熔融温度随硬链段含量减少而降低,但其结晶温度几乎不变。

The polyamide-polyether multiblock copolymers consisting of Nylon 1010 as hard segments and polyether as soft segments were synthesized from COOH- terminated Nylon 1010 with polytetramethylene glycol in the presence of catalyst by melt condensation.The effects of different composition ratios of hard segments and soft segments on the crystalline morphologies, melting and crystalline temperatures of multiblock copolymers were investigated using TEM and DSC techniques.If the contents of hard segments in multiblock copolymers are high, very good spheru-lite structures which consist of lamellae are clearly visible under TEM, however it exhibits small crystallities at low contents of hard segments. Fig.1 shows electron micrograph of sample PA-71.6, the number of PA-71.6 denotes the content of Polyamide segments without staining,the crystalline structures of sample PA-71.0 and sample PA-59.1 are sph-erulities consisting of lamellae of Ca. 200-300 A and 100-200 A in thickness and of 2500 and 1450 in molecular weight of polyamide segments respectively.The melting temperatures of these multiblock copolymers decrease with the decrease of the contents of hard segments, but the crystalline temperatures are nearly constant at 162℃.