Modification Of Poly (Phthalazinone Ether Ketone)s And Poly (Phthalazinone Ether Sulfone)s

Poly (phthalazinone ether ketone)s (PPEKs) and Poly(phthalazinone ether sulfone)s (PPESs), a series of novel high performance polymers with remarkable thermal resistance and solubility developed by Dalian University of Technology, have a strong competitive capability in international markets. However, the pure resin shows some shortcomings in processing and application. For example, the melt viscosity is too high to process and the high friction coefficient and specific wear rate, the brittleness and wear rate is unbeneficial to commercialization. Therefore, blending PPEKs and PPESs with other high performance polymers was adopted in order to improve their properties. In this paper, structures and properties of these blends were studied systematically, which was foundations in their industrialization and application.Melting blends of poly (phthalazinone ether sulfone)(PPES)/poly (ether sulfone)(PES) were prepared by two screw extruder. Miscibility of blends was investigated via differential scanning calorimetry ( DSC ) and scanning electron microscopy(SEM). The results show that PPES/PES blends are miscible in all compositions. Excellent mechanical properties were showed for PPES/PES blends. The thermal degradation dynamic of PPES in nitrogen was studied and through thermo-gravimetric analysis (TGA). Degradation reacting index and active energy were determined. Two steps are showed for thermal degradation of PPES and the degradation index is 1. Degradation active energy shows a tendency of deduction with the loss weight at elevated temperature. Thermal stability of blends was slightly decreased with increase of PES content. Dynamic mechanical properties of PPES and its blends with PES were determined by using dynamic mechanical testing analysis (DMTA). Storage modulus of PPES is very high under 280 and samples shows outstanding thermal resistance. Only one peak of glass transition temperature is detected for all the samples, which further proves the good miscibility of blends.Poly(phthalazinone ether ketone)(PPEK)/poly(phenylene sulfide)(PPS) blends with different compositions were prepared through two screw extruder. Rheological properties of PPEK/PPS blends were tested in a capillary rheometer. Psedoplastic behaviors are shown forthe blends with PPS content under 40% at chosen shear rates and temperatures, and Newton behavior for the blends containing 60% PPS. Viscosity of PPEK has remarkably decreasing and the appearance is improved after blending with PPS. The thermal stabilities of PPEK and its blends with PPS were studied by TGA. Two steps are shown for thermal degradation of PPEK and 5% weight loss temperatures increases with the rising of heating rate. In nitrogen, degradation reaction index of PPEK is not 1, which shows there are different mechanisms of degradation for PPEK and PPES. 5% weight loss temperatures for all the blends almost remain, which indicates blends still have good thermal stabilities.PPEK were modified by blending with poly(ether imide)(PEI). Phase behaviors of blends were studied using ternary-solution methods, DSC, SEM. The results show that PPEK/PEI and PPEKK/PEI blends are miscible in all compositions. The FT-IR results yield evidence that physical interactions leading to miscibility or compatibility of these blends are weak and no apparent specific interactions exist between two polymers in the blends. Therefore, the miscibility of PPEK/PEI blends could be contributed to the lower repulsion between the two constituent polymers. The blends have excellent high-temperature resistance according to TGA of blends.PPEK and poly(tetrailuoro ethylene)(PTFE) blends were prepared via solution blending. Tribological properties of blends were tested on a M-200 wear testing machine and wearing mechanism were analyzed on the base of SEM and scanning probe microscope controller (SPM). Effects of loads, velocities, and compositions on morphologies, friction coefficients, wear volume and rates are very remarkable. According to TGA, onset degradation temperatures and maximal deg...