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The feasibility study of utilizing sunflower oil as renewable biomass source to develop highly effective inhibitors for mild steel corrosion (MS) in the 15% HCl medium was done by weight loss, potentiodynamic polarization (PDP), dynamic electrochemical impedance spectroscopy (DEIS), and electrochemical impedance spectroscopy (EIS), supported with energy-dispersive X-ray (EDX), atomic force microscopy (AFM), and field-emission scanning electron microscope (FESEM) techniques. Moreover, a complementary theoretical investigation was carried out to clarify the inhibition mechanism of inhibitors by density functional theory (DFT), density functional based tight-binding (DFTB), and molecular dynamics (MD) simulation approaches. The obtained results confirm that sunflower-oil-based corrosion inhibitor (SFOCI) has a significant anticorrosion property toward the dissolution of MS in 15% HCl solution in the temperature range 20–80 °C. In addition, the results show that SFOCI could provide an inhibition efficiency of 98 and 93% at 60 and 80 °C, respectively. The inhibition mechanism of SFOCIs was mixed-type and their adsorption on the surface of MS was mainly chemisorption. The FESEM and EDX studies proved the presence of SFOCI molecules on the surface of MS. In addition, the adsorption energy of SFOCI indicated an intense interaction between the inhibitor and surface of Fe. The results of this study could open a new window for the design and development of scalable and effective eco-friendly vegetable-oil-based corrosion inhibitors for highly corrosive solutions at high temperatures.

A series of tertiary aminosquaramides as bifunctional organocatalysts in the ring-opening polymerization (ROP) of L-lactide (L-LA) were developed, allowing the activation of both the L-LA monomer and the alcohol group of the initiator/propagating species. Further, the impact of tertiary nitrogen substituents on catalytic activity in ROP of L-LA was explored. The tertiary aminosquaramide-an air-stable and moisture-stable catalyst-exhibited superior activity in contest with thiourea counterpart when both were equipped with a similar tertiary amine group. Kinetic and chain-extension experiments indicated that the formed poly(L-LA) is featured with narrow polydispersity and high end-group fidelity, hallmarks of a living polymerization process. The initiator efficiency was further executed at ease by preparation of an ABA triblock copolymer poly (L-LA)-b-poly (ethylene glycol)-b-poly (L-LA) in the presence of a dual-headed PEG macroinitiator. 1 H NMR titration experiments suggested a bifunctional catalytic mechanism, wherein both the L-LA monomer and the propagating hydroxyl group were activated en route to polymerization. The 1 H NMR, SEC, and MALDI-TOF MS measurements validated the quantitative incorporation of the initiator in the polymeric chains and enchainment over competitive transesterification reaction. Overall, the structure-activity relationships were surveyed to uncover aminosquaramide as a new bifunctional dual hydrogen-bond donor catalyst for living ROP of L-LA.Of the existing living polymerization techniques, organocatalytic ring-opening polymerization (ROP) 4 -invented by Hedrick and co-workers 5 -is featured by its ability to provide a variety of structurally well-defined polymers. These polymers are featured with remarkably low degree of polydispersity and excellent end-group fidelity, making this procedure particularly attractive for the preparation of advanced polymeric materials. 6 Also, the requisite absence of metal residue, and efficient catalyst removal from the final polymers for biomedical 7 and microelectronic 8 applications advocate the use of such sustainable approaches versus metalcatalyzed processes. Thus, a broad range of organocatalytic systems that function by different modes of activation (monomer, initiator, polymer growing chain) have been developed. 4Among various fascinating systems, the binary catalytic systems composed of a hydrogen bond donor (HBD), and a wide-ranging slate of hydrogen bond acceptors (HBA) represent the current state-of-the-art in organocatalytic ROP of cyclic esters. 9 These systems are believed to affect catalysis through hydrogen bond mediated activation of HBD upon monomer and of HBA upon alcohol, respectively. However, the catalytic activity of such systems could be attenuated because of the following drawbacks: (i) low Additional Supporting Information may be found in the online version of this article.

A novel waterborne polyurethane based on main chain degradation under acidic and reductive conditions of tumors was synthesized.