Polypropylene (PP)/thermoplastic polyester elastomer (TPEE) blends were prepared. To enhance the compatibility between the two phases, maleic anhydride-grafted polypropylene (MA-g-PP) was applied during melt-mixing. The morphology obtained from scanning electron microscopy (SEM) showed that TPEE was not miscible with PP, however, those of the PP/TPEE/MA-g-PP indicated that PP and TPEE turned to miscible because MA-g-PP served as an effective compatibilizer. The tensile tests confirmed that the tensile strength of the PP/TPEE blends decreased and the elongation increased with increasing TPEE content. The increase in tensile strength of the PP/TPEE/MA-g-PP blends was associated with the morphology shown by SEM and internal structure. X-ray diffraction (XRD) confirmed that compared to the PP/TPEE blend, the intensity of the 20.9° peak of the PP/TPEE/MA-g-PP increased and that of the 21.6° peak decreased gradually due to the MA-g-PP. In differential scanning calorimetry (DSC), the crystallinity (Xc) of the PP/TPEE blends decreased with increasing TPEE content. The PP/TPEE/MA-g-PP blends showed a single weak glass transition (Tg) peak due to the compatibility between the PP and TPEE. The thermal stability of the PP/TPEE blends with MAg-PP was also higher than that of the PP/TPEE.

폴리프로필렌/열가소성 폴리에스터 엘라스토머(PP/TPEE) 블렌드를 제조하였다. 두 상의 상용성을 증가시키기 위하여 maleic anhydride-grafted polypropylene(MA-g-PP)를 배합 도중 첨가하였다. SEM을 통한 모폴로지 분석 결과, 두 상은 상용성이 없었으며 MA-g-PP를 첨가한 결과 상용성이 발현되어 MA-g-PP가 효과적인 상용화제로 작용하였다. MA-g-PP를 첨가한 PP/TPEE 블렌드는 XRD 분석 결과 20.9° 피크의 강도가 증가하였으며 21.6° 피크는 점차적으로 감소하였다. 상용화제가 첨가된 경우의 기계적 물성 증가는 SEM 및 XRD의 분석 결과와 부합하였다. DSC 분석 결과, TPEE의 함량이 증가할수록 결정화도가 감소하였으며 MA-g-PP가 첨가된 경우 상용성으로 인하여 단일의 유리전이온도가 관찰되었으며 열적 안정성이 증가되었다.

Keywords: polypropylene; thermoplastic polyester elastomer; blends; compatibilizer