Study On Compatibility Of PPO/PA66 Auoy And Its Impact On Performance

In this paper, polyphenylene ether/polyamide 66 (PPO/PA66) was used as the matrix alloy, and SEBS-g-MA as the impact modifier and auxiliary compatibilizer. The effect of compatibilizers, SMA and PS-g-PA6, on the mechanical properties, processing performance and microscopic morphology were investigated. The results showed that, SMA and PS-g-PA6 have improved overall performance of the alloys to some extent, taking an excellent compatibilization effect. The main conclusions are listed below:1. The compatibilizer of SMA, with different contents, has saturation point for effect of PPO/PA66/SEBS-g-MA alloy compatibilization. Meanwhile, the desirable dosage of SMA in the PPO/PA66/SEBS-g-MA alloy corresponding PA66-rich phase and PPO-rich phase also differs. The dosage of SMA in alloy corresponding PA66-rich phase was more than the one corresponding PPO-rich phase, and took greater influence. The most desirable overall strength of the PPO/PA66/SEBS-g-MA (30/70/20) and (70/30/20) was achieved when dosage of 2-4 phr and 1-2 phr, respectively.2. The impact energy dissipation and shock fracture process morphology were investigated by instrumented impact and scanning electron microscopy to study the PPO/PA66/SEBS-g-MA/SMA blends. The study found that, alloy dispersed phase was refined and distributed more evenly when adding SMA. Meanwhile, SMA can promote the SEBS-g-MA distributed in phase of PA66 and reduce the interfacial tension of the alloy. Therefore, SMA improved alloy crack initiation and propagation energy, obtaining maximum toughness index DI for 2phr SMA, which fracture initiation energy was much larger than the crack energy.3. The compatibility agent, SMA, could promote PS block segment itself to stretching to SEBS-g-MA and the MA function chemically to be linked to the end amino group of PA66, thereby increasing the single phase and the alloy viscosity. The viscosity of the system was maximized when adding to a certain amount of SMA and then began to decrease.4. The graft polymeric compatibilizer, PS-g-PA6, was successfully prepared via anionic and free radical polymerization. The compatibilizer of PS-g-PA6 showed a great enhanced effect on the mechanical strength of the PPO/PA66 alloy. The tensile and blending strength of the alloy increased with the PS-g-PA6 content increasing. When increased to 8phr, tensile strength and bending strength achieved maximum, with an increase of 36.4% and 16.6%, respectively.5. The impact strength, the energy dissipation and morphology of the PPO/PA66/ SEBS-g-MA/PS-g-PA6 blends were studied. The results showed that, the compatibilizer of PS-g-PA6 could refine the dispersed particles, promote the distribution of dispersed particles and lead to crack and propagation energy expansion, obtaining the maximum value for toughness index DI for 6phr PS-g-PA6 used.6. The dynamic mechanical property of the PPO/PA66/SEBS-g-MA/PS-g-PA6 blend was studied. The study found that the compatibilizer of PS-g-PA6 could get the glass transition temperature of PA66 and PPO phase closer to the center. The minimum was obtained when 6-8phr dosage was used.7. The rheological behavior of the PPO/PA66/SEBS-g-MA/PS-g-PA6 blend was studied. The study found that, the PPO/PA66/SEBS-g-MA/PS-g-PA6 melt belonged to pseudoplastic fluids with fluid shear-thinning behavior. With the increase of PS-g-PA6 content, Newtonian index of n decreased, showing a greater shear thinning behavior. Dynamic strain sweep found that, PS-g-PA6 could enhance inter-molecular forces and increase the storage modulus of the alloy and the critical strain of the alloy decreased with increasing PS-g-PA6 content. Therefore, PS-g-PA6 took a great effect on compatibilization of PPO and PA66 in PPO/PA66/SEBS-g-MA blends.