Study On The High-performance Poly(phenylene Oxide)/Nylon 6 Blends

PP0/PA6 alloy integrates the advantages of PPO and PA6. Because of its excellent properties, PPO/PA6 attracts more and more attentions. However, the studies on PPO/PA6 alloys in China are far behind those in foreign countries, especially in the high-tech fields, contemporarily. This thesis dedicates to improve the properties of PPO/PA6 to meet the requirements in the high-tech fields.Taking active monomer glycidyl methacrylate (GMA) as grafting monomer and styrene (St) as comonomer, grafted polymer PPO-g-(GMA-St) is prepared by melt-grafting of polyphenyl ether (PPO). The grafted polymer is characterized by infra-red spectroscopy and the percent grafting is obtained by chemical titration. It is found that the percent grafting of GMA could be improved remarkably with the add of styrene. Using PPO-g-(GMA-St) as compatibilizer, the composites of PPO/PA6/PPO-g-(GMA-St) is obtained by melt compounding of PPO and PA6. As could be seen from SEM, after adding compatibilizer PPO-g-(GMA-St), the phase morphology of the composites changed from sea-island structure to co-continuous structure; From Molau test, dynamic viscoelastic test and dynamic mechanical analysis, it is also confirmed that PPO-g-(GMA-St) has an in-situ compatibilization effect to the PPO/PA6 blend. Moreover, the mechanical properties and water absorbency of the blend were improved. the tensile strength of the composites improved from 42.0 MPa to 59.5 MPa, impact strength improved from 2 kJ/m²to 3.7 kJ/m², and the water absorbency declined from 1.75 % to 1.46 %.Considering the excellent properties of carbon nanotubes (CNTs) to composites, CNTs were introduced to PPO/PA6 blend by melt compounding. The effect of CNTs was studied. Firstly, CNTs was modified to CNTs-x(x=COOH, OH, or NH₂) by chemical method. With CNTs-x of 1 phr, the phase morphology of the composites could be changed from sea-iceland structure to co-continuous structure, no matter x= OH, NH₂ even the pure CNTs. However, the phase morphology of the nanocomposites showed no change when x=COOH. It was found that PPO/PA6/CNTS-NH2 has the best mechanical properties and rheological among three kind of nanocom. posites. Furthermore, adding PPO-g-MAH to the composites will improve, the dispersibility of CNTs-x and the mechanical properties of the composites.