Properties of Styrene–Maleic Anhydride Copolymer Compatibilized Polyamide 66/Poly (Phenylene Ether) Blends: Effect of Maleic Anhydride Concentration and Copolymer Content

Abstract

Polyamide 66 (PA66)/poly (2,6-dimethyl-1,4-phenylene ether) (PPE) blends with a ratio of 50/50 (w/w) were produced by a twin-screw compounder. The immiscible blends were compatibilized using two different styrene–maleic anhydride copolymers (SMA) with a low (SMAlow) and a high (SMAhigh) maleic anhydride (MA) concentration of 8 and 25 wt%, respectively. Furthermore, the SMA content was varied from 0 to 10 wt%. The influence of MA concentration and SMA content on the morphological and thermomechanical properties of PA66/PPE blends was investigated. Herein, we established correlations between the interfacial activity of the SMA with blend morphology and corresponding tensile properties. A droplet-sea to co-continuous morphology transition was shown by scanning electron microscopy to occur between 1.25 and 5 wt% in the case of SMAhigh. For SMAlow, the transition started from 7.5 wt% and was still ongoing at 10 wt%. It was found that SMAlow with 10 wt% content enhanced the tensile strength (10%) and elongation at break (70%) of PA66/PPE blends. This improvement can be explained by the strong interfacial interaction of SMAlow within the blend system, which features the formation of nanoemulsion morphology, as shown by transmission electron microscopy. Very small interdomain distances hinder matrix deformations, which forces debonding and cohesive failure of the PPE phase as a “weaker” main deformation mechanism. Due to a lack of interfacial activity, the mechanical properties of the blends with SMAhigh were not improved.

Properties of Styrene-Maleic Anhydride Copolymer Compatibilized Polyamide 66/Poly (Phenylene Ether) Blends: Effect of Blend Ratio and Compatibilizer Content

“…A morphology transition is mainly induced either by a change in blend ratio or by a shift of the viscosity ratio between the dispersed and matrix phases [53,54]. For a constant blend ratio, a shift in the morphology induced by SMA copolymers was already reported elsewhere [47]. Inclusions within the PA66 phase, only apparent when SMA was added, leads to an increase of the PA66 viscosity, thus shifting the viscosity ratio between PA66/SMA and PPE to closer values.…”

“…It seems that the SMA's compatibilizing mechanism is based on an emulsification of the PPE domains, revealing nano-sized droplets by pinch-offs as a result of surface roughening of the PPE phase [14,16,55]. In our previous work [47], we reported that the small droplets either consist of PA66-g-SMA micelles (smaller 50 nm) or more likely PA66-g-SMA micelles swollen by PPE (larger 50 nm). Up to now, no analysis was done to confirm the theory of swollen micelles for PA-based PPE blends.…”

“…Compatibilization is mainly performed by PPE-graft-MA [42][43][44], organo-montmorillonite [45] and SMA/(styrene-ethylene-butylene-styrene copolymer)-graft-MA dual compatibilizers [46]. In our previous study [47], we established structure-property-relationships of SMA compatibilized PA66/PPE blends for the first time. We investigated the effect of two different SMA copolymers (8 wt% and 25 wt% MA concentration) on the morphological and mechanical properties.…”

Compatibilization of Poly(Lactic Acid) (PLA)/Plasticized Cellulose Acetate Extruded Blends through the Addition of Reactively Extruded Comb Copolymers

“…Then, the most evident effect of compatibility is the presence of bonds at the interface, resulting in an increased stiffness and a decreased deformability of the matrix. This effect was observed in several cases, as an example in polyamide blends [ 41 , 42 ], polyester [ 43 ], or polycarbonate [ 9 , 44 ] based blends. Interestingly, the addition of C1 to pAC gave the best value of tensile strength, probably because of the achievement of a good balance between increased stiffness and deformability of the matrix.…”

Influence of the structure of sub‐micrometer core‐shell rubber particles and matrix composition on the mechanical properties, morphological structure and deformation mechanism of rubber‐modified polyphenylene oxide/polystyrene blends

“…The PPS/PPO blends showed extraordinary impact strength values (maximum of 63.6 kJ/m 2 ), higher than those of common blends by 10 folds. Aksit, Zhang et al 29,30 found that PA66/PPO blends can effectively be compatibilized using SMA and HIPS-g-MAH, increased the elongation at break of the blends by 70%, and 65%, respectively, effectively improved the toughness of the blends. Bin et al 26 studied HDPE/PPO blends and used SEBS as a compatibilizer to improve the properties of blends.…”