Study On Grafting Of Polyphenylene Oxide And Its Blend With Polyamide

Macromolecule peroxide of polyphenylene oxide (PPO) was prepared by β ray pre-irradiation method. The grafting of AA or MAH onto PPO was carried out with macromolecular peroxide of PPO as an initiator by reactive extrusion. The effects of irradiation dose, monomer content and screw run speed on degree of grafting were studied. Chemical structures of graft copolymers were characterized by Fourier transform infrared (FTIR) spectroscopy. Comparing with the FTIR spectrum of pure PPO, FTIR spectra of the graft copolymers showed new characteristic absorption peaks at1742cm-1and1753cm-1,1711cm-1, which attributed to characteristic groups of AA and MAH monomer, respectively. This result indicated that AA and MAH monomer had been grafted onto PPO molecular chain successfully, respectively. The wettability result of graft copolymers indicated that the contact angle decrease with increasing of degree of grafting. The thermal properties of graft copolymers were analyzed by differential scanning calorimety (DSC). It was found the melt temperature (Tm) of graft copolymers did not change through compared with PPO. Mechanical properties of graft copolymers were measured, that compared with PPO, the values of tensile strength and elongation at break were no obvious change. Rheological properties of graft copolymers were investigated with a rotational rheometer. It was found that storage modulus, loss modulus and complex viscosity of the graft copolymers were higher than those of PPO.High performance PPO/PA66alloy was prepared by reactive blend. Properties of PPO/PA66blends were investigated. DSC result indicated that the melt temperature (Tm) of PA66phase increased, the molten peaks of two components of PPO and PA66moved more close in PPO/PA66alloy when the content of PPO-g-MAH was improved. The vicat softening point and water absorption of PPO/PA66alloy were measured, it was found that the softening point temperature of PPO/PA66alloy increased and water absorption of PPO/PA66alloy decreased with the content of PPO-g-MAH increasing. Morphologies of PPO/PA66alloy were investigated by using scanning electron microscopy (SEM). Comparing with PPO/PA66blends, PPO-g-MAH/PA66showed that the dispersed phase size decreased and well-distributed. This suggested that the improvement of compatibility between PPO-g-MAH and PA66could reduce the interfacial tension and increase the interfacial adhesion. The mechanical tests showed the tensile strengths and impact strengths of PPO-g-MAH/PA66blends were higher than those of PPO/PA66blends. Rheological results found that complex viscosity, storage modulus and loss modulus of PPO-g-MAH/PA66were higher than those of PPO/PA66blends, it demonstrated that PPO-g-MAH could react with PA66and be a good reactive compatibilizer in PPO/PA66blend system.