Study On Preparation And Properties Of PB-1/PP Blends

Iso-polybutene-1 (PB-1) is honored as the "golden plastic", which is majnly used in the manufacture of pipe area instead of metal pipe because of the good properties such as thermo stability, creep resistance, environmental stress crack resistance, flammability resistance, grinding resistance, superior processibility. While there are some disadvantages within PB-1, such as the poor toughness processed by injection and it needs a long period to reach the relative steady and super properties. In this paper, the fundamental properties of PB-1 was studied, and then to blend PB-1 with Polypropylene (PP) to produce the blends of PB-1/PP. The effect of heat treatment on the PB-1/PP blends was investigated. PB-PP, which synthesized by solution graft and croslinking polymerization, was used to blend with PB-1/PP as compatibilizer to prepare the blends of PB-1/PP/PB-PP. The morphology, the crystallization, dynamic properties, mechanical properties and the melt rheological behavior as well as the thermal deformation property of the blends were studied via polarized optical microscopy (POM), differential scanning calorimetry (DSC), dynamic mechanical analyzer (DMA), Wide angel X-Ray Diffract meter (WXRD), mechanical testing machines and capillary rheometer, respectively.It was found that it needed 7 days for PB-1 to fulfill the transition from the crystal formⅡ to crystal formⅠ, and the properties would maintain unchanged; After adding with PP component, both the spherulites of PB-1 and PP were refined, with the size of spherulites reduced; the tensile property of PB-1 was decreased and the impact and bending properties were improved noticeably; the change of the melt viscosity of the blends with the shear rate was more sensitive than the pure i-PB, and the heat deflection temperature improved.Heat treatment could make the crystallization of the blend more perfect, improving the comprehensive properties. With the heat treatment time of 2 hours at the temperature of 75 ℃, the effect would be the most obvious. In the system of PB-1/PP/PB-PP, the adding of PB-PP as the compatibilizer enhanced the adhesive interaction between the two phases, which improved the compatibility of the blends in some certain, hence, the comprehensive properties of the blends were improved. When the content of BPO was 1.5phr and the reaction time was 3 hours, the effect of the compatibilizer was the most noticeable; with the ratio of PB-1/PP/PB-PP was 80/20/4, the comprehensive properties of the blend was the best.