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Polyamide is an engineering plastic, which has been widely used in industry and life. Polyamide 56, as a green and environmentally friendly bio-based product, is gradually replacing traditional petroleum-based products. However, in terms of auto parts, communication equipment, and mechanical products, a single polyamide monomer is difficult to meet the end-use standard. EPDM-g-MAH (ethylene propylene diene monomer grafted with maleic anhydride) is melt blended with bio-based polyamide 56 (PA56) in a twin-screw extruder to obtain polyamide elastomers with different formulations. Subsequently, its morphology and structure, thermodynamic properties, crystallinity, and mechanical properties were analyzed. The test results show that the composites containing 10% EPDMg-MAH have better impact resistance and thermal properties in the range of adding 0-20 wt% EPDM-g-MAH. In the fracture morphology analysis, it is found that the interface between the rubber phase and the polyamide phase fused well, and the elastomer showed the ductile fracture.

The super-tough bio-based nylon was prepared by melt extrusion. In order to improve the compatibility between bio-based nylon and elastomer, the elastomer POE was grafted with maleic anhydride. Scanning Electron Microscopy (SEM) and Thermogravimetric Analysis (TGA) were used to study the compatibility and micro-distribution between super-tough bio-based nylon and toughened elastomers. The results of mechanical strength experiments show that the 20% content of POE-g-MAH has the best toughening effect. After toughening, the toughness of the super-tough nylon was significantly improved. The notched impact strength was 88 kJ/m2 increasing by 1700%, which was in line with the industrial super-tough nylon. X-ray Diffraction (XRD) and Differential Scanning Calorimetry (DSC) were used to study the crystallization behavior of bio-based PA56, and the effect of bio-based PA56 with high crystallinity on mechanical properties was analyzed from the microstructure.

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Hot-melt pressure-sensitive adhesives (HMPSAs) with polystyrene-isoprenestyrene (SIS) as the backbone material are widely used in transdermal drug delivery systems (TDDS) because of their high cohesive strength and drug-carrying capacity. However, it is restricted by its high hydrophobicity when loaded with hydrophilic drugs. In this study, HMPSAs with amphiphilic properties were created by mixing SIS with fatty alcohol polyoxyethylene ether (AEO-9) and polyethylene glycol (PEG) of different molecular weights to improve the ability of HMPSAs to deliver hydrophilic drugs. The effects of different molecular weights of PEG on the hydrophilicity of HMPSAs were also investigated. Additionally, gardenia glycosides and oleanolic acid were selected for drug release experiments.Compared to untreated HMPSAs, HMPSAs modified with AEO-9 and PEG2000 could convert from hydrophobic to hydrophilic. The contact angle could be reduced from 91.8 to 25.6 , and the 24-hour water absorption could be raised by 170%. The drug release experiments demonstrate that SIS/AEO-9/PEG2000 enhances the release efficiency of the hydrophilic drug gardenia jasminoides by 69%. In summary, as a novel amphiphilic medicinal HMPSAs, SIS/AEO-9/PEG offered a broad application promise in hydrophilic drug release.