ステアリン酸アミドのブルーム挙動におけるNBR表面と内部のモルホロジー

抄録

Morphological changes of stearamide(SA) in surface and matrix NBR has been investigated for 10phr SA-containing NBR samples by reference to the blooming pattern and thermal analysis data of samples. The initial bloom film on the sample surfaces(immediately after mold) was composed of plate crystals. Initial blooming SA crystals become large in order of 18%AN-NBR<40% AN-NBR<29%AN-NBR. Initial SA particles in NBR matrix become large in order of 18% AN-NBR<<29%AN-NBR<40%AN-NBR. In the blooming of 18%AN-NBR sample, bloom film on surface changed with blooming time from small plates to large plates and again small plates. In 29%AN-NBR and 40%AN-NBR. samples, bloom films changed with blooming time from plate to needle crystals. In 18%AN-NBR sample, SA particles disappeared after 240h at 70°C from the results of thermal analysis and SEM photographs. In 29%AN-NBR and 40%AN-NBR. samples, large SA particles did not change so much in size but small particles decreased their amount to a certain particle size. Those results lead to the conclusion that in viewpoint of surface and matrix morphology, the blooming of SA in NBR does not suit basically to both the supersaturation theory of Williams and free energy slope theory of Nah.