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Long carbon chain thermoplastic polyamide elastomer (TPAE) with PA1212 as hard segment and polytetrahydrofuran as soft segment was synthesized successfully. Subsequently, thermoplastic polyurethane (TPU) incorporated to compensate for the high cost of TPAE and improved the foaming performance, in which a chain extender (ADR) was applied to enhance melt strength and interfacial compatibility simultaneously. The effect of ADR content on the mechanical, thermal, rheological, and foaming properties of TPAE/TPU composites were investigated in detail. It was found that the composite foams showed a more perfect cell structure, high cell density, and increased expansion ratio because of the enhanced melt strength and interfacial compatibility, when ADR was incorporated. With the increase of ADR content, the cell size and expansion ratio of the composite foams with TPU content of 30% showed a trend of first increasing and the following decreasing. The cell size reached a maximum value when the content of ADR was 2%, which was 25.81 [micro]m. Consequently, the obtained TPAE/TPU composite foams showed an outstanding compressive modulus and resilient performance to broaden its application in footwear industry. KEYWORDS chain extension, foams, interfacial compatibility, polyamide elastomer, polyurethane, orcid.org/0000-0001-5371-9615 1 | INTRODUCTION Polymer foams almost cover all fields of industrial production and life, due to the excellent properties including lightweight, high specific strength, fine thermal and sound insulation, [...]

Thermoplastic polyamide elastomers (TPAEs) were synthesized using polyamide 6 (PA6) as hard segments and polyethylene glycol (PEG) as soft segments. The prepared TPAEs showed a superior mechanical property and thermal property, which the strength and elongation-at-break reached 35.50 [+ or -] 3.54 MPa and (316.05 [+ or -] 20.58)%, respectively, when the molecular weight of soft segment was 600. Furthermore, crystallization property and microphase separation of TPAEs were also investigated in detail, having a significant influence on the foaming behavior of the obtain elastomers. Owing to the restriction of crystalline hard segments, only a few cells formed in the amorphous soft segment regions at foaming temperature of 140[degrees]C, while it transformed to larger cells with a thin cell wall at foaming temperature of 160[degrees]C and above. When the molecular weight of soft segment increased from 300 to 1000, the average cell size of the foamed TPAEs at 160[degrees]C enlarged from 28.73 to 42.17 [micro]m, while the cell density decreased from 5.26 x [10.sup.8] #/[cm.sup.3] to 4.25 x [10.sup.8] #/[cm.sup.3], both expansion ratio and shrinkage ratio increased gradually. KEYWORDS crystallization, foaming behavior, mechanical property, microphase separation, thermoplastic polyamide elastomers, 1 | INTRODUCTION Thermoplastic polyamide elastomers (TPAEs) are a new member of the thermoplastic elastomer family, composed of rubber-phase polyester or polyether and plastic-phase polyamide (PA), including PA6, PA12, PA11, [...]

Given the toxicity of wastewater pollutants to both humans and the environment, it is critical to develop a new synthetic membrane with superior permeability and rejection. Herein, a novel asymmetric polyethersulfone (PES) composite filtration membrane was successfully prepared using a simple alternating vacuum‐deposition process with positively charged chitosan and negatively charged cellulose nanofibrils as polycations and polyanions, respectively. As expected, the produced PES composite filtration membranes had a compressed and negatively charged surface, which prevented the anionic dye methyl blue (MB) molecules from infiltrating into the membrane matrix. Consequently, the resulting PES composite filtration membranes exhibited an extremely high MB rejection (99.7%) and a satisfactory flux (37.47 L h−1 m−2 MPa−1). In addition, the composite membrane demonstrated extremely selective removal of anionic dyes in the presence of neutral dyes due to the Donnan effect. Furthermore, the developed PES composite filtration membranes displayed exceptional long‐term stability (99.8% rejection and 36.5 L h−1 m−2 MPa−1 flux after 50 h of filtration) and recycling properties (90.1% flux recovery rate after 3 cycles of running). In conclusion, the PES composite filtration membranes prepared in this study presented great potential in wastewater filtering. [ABSTRACT FROM AUTHOR]