Research On Nylon 11 Modification Polypropylene Alloys

As one general thermoplastic, polypropylene posses significant mechanical performance besides imperfects of brittleness at low temperature, apparent shrinking rate and aging. Nylon 11 takes on excellent cold-resistance and endurance. PP/PA blends may improve impact property, endurance, modification dimensional stability and processing of products due to being comprehensive of characters of PP and PA. However, polar difference induces weak compatibilization, it is the hot to study compatiblization.First, in this paper, functional compatibilizer PP-g-MA and traditional random styrene-maleic anhydride copolymer are chosen to compatibilize PP/PA11 system that characterized through FTIR and DSC. FTIR investigation shows PP-g-MA is reactive compatibilizer but RSMA through physical compatibilization; DSC analysis indicates the two compatibilized systems are part compatibilization. To PP/PA11/PP-g-MA, addition of PP-g-MA affect crystallization of PP phases and degree of crystallization is even higher than that of RSMA , which induces blends higher brittleness.Mechanical properties research to compatibilized systems show tensile strength reaches 35.3 MPa and 35.4 MPa respectively to PP/PA11/RSMA as composition 87/5/8 and 85/10/5, which improve approximately 6% compare to pure PP. To PP/PA11/PP-g-MA systems, the tensile strength is achieved 36.4 MPa in which PP-g-MA content is 3% and PA11 are 5% and 10% weight. At the same ratio of compositions, Izod notched impact strength of RSMA compatibilized blends is higher than that of PP-g-MA. The two compatibilized systems are pseudo-plastic fluids through rheological character study. RSMA compatibilized system posses more apparent pseudo-plastic than that of PP-g-MA at the same compounding ratio and the rheology changes distinctly with the increasing of temperature, whereas melting viscosity is insensitive to temperature for PP-g-MA system because of cross-linking structure which acid-anhydride and amidogen in nylon 11 reacted.To toughening alloys, as PP/PA11/PP-g-MA/EPDM-g-MAH composition is 84/5/3/8, the notched impact strength of PP-g-MA compatibilized is reached maximum 46.7 J/m, which is 2.3 to 2.8 times relative to PP. With EPDM-g-MAH increasing, impact strength of two systems are improved when nylon 11 is 10% and PP-g-MA compatibilized system is faster increased than that of RSMA. The alloy is evidently enhanced toughness while maintaining tensile strength of PP.