Polypropylene mixed with untreated mica showed spherulites growing randomly when the polymer was kept at a crystallization temperature after being melted at 200℃. However, transcrystallization occurred on the side of the mica which was treated with a silane coupling agent. The width of the transcrystalline region grew linearly when the polymer was kept at 120℃, 123℃, 125℃ and 127℃ after being melted. The activation energies calculated from the slope of the growth fate-crystallization temperature are 85.0kcal/mol for the initial crystallization and 83.1kcal/mol for the second crystallization, respectively. The growth rate of the crystalline region at the second cooling is larger than that at the initial cooling, and the ratio(r₂/r_l) of the growth rate between the initial cooling (r_l) and the second (r₂) is always 1.11. The number of spherulites appeared in the bulk of the polymer at the second cooling was always smaller than that at the initial cooling.

표면처리를 하지 않은 mica와 혼합된 용융 Polypropylene이 냉각될 때 mica와 관계없이 spherulite가 생겨났으나 표면처리를 한 시료에서는 mica 입자의 측면에서 transcrystallization 현상이 관찰되었다. Transcrystalline 폭은 120℃, 123℃, 125℃ 및 127℃ 등온상태에서 직선적으로 증가하였다. 결정화온도에 따른 결정성장 속도로부터 구한 활성화 에너지는 1차 결정화 때 85.0kcal/mol이며 재 결정화 때는 83.1kcal/mol로 나타났다. Transcrystalline growth rate는 1차 결정화 때보다 재 결정화 때가 높게 나타났으며 각 온도에서 나타난 1차결정 growth rate (r_l)와 재결정 growth rate (r₂)의 비(r₂/r_l)는 1.11로서 모든 온도에서 일정한 값을 나타내었다. 한편 mica 표면을 제외한 PP matrix 에서 나타나는 spherulite의 수는 재결정화 때가 1차 결정화 때보다 적게 나타났다.

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