High impact strength for polypropylene/titanate whisker composites with dual compatibilizing agents

Compatibilizing agents, namely, maleic anhydride‐grafted polyolefin elastomer (POE‐ g ‐MAH) and maleic anhydride‐grafted polypropylene (PP‐ g ‐MAH), were simultaneously employed in isotactic polypropylene (PP)/titanate whisker composites for high impact toughness and improved mechanical properties. POE‐ g ‐MAH was used in the composites for reinforcing impact strength of PP. In the meanwhile, PP‐ g ‐MAH compatibilized counterpart was enrolled for modulating the composite properties. With 3‐aminopropyl triethoxysilane modified whiskers, compatible compatibilizing agent PP‐ g ‐MAH contributed to maintain the tensile property, while POE‐ g ‐MAH compatibilized content was prone to improve the composites of PP/whisker with notch impact strength of 9.9 ± 0.7 kJ/m ² , which was ~220% higher than that of PP. Validity of interface regulation revealed that POE‐ g ‐MAH and PP‐ g ‐MAH were dominated separately to improve impact and tensile strengths with the diversely compatibilized part ratio, and strived in combination for more superior mechanical properties. β‐Form crystals detected by differential scanning calorimetry in the composites favored the extra improvement of tenacity, and crystalline morphology confirmed the promoted heterogeneous nucleation of PP composites with addition of PP‐ g ‐MAH. Variations of glass transition temperature and loss factor also indicated the different effects of the two compatibilizers on the interface between whiskers and PP matrix. POLYM. COMPOS., 40:3421–3428, 2019. © 2019 Society of Plastics Engineers