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Graphic AbstractFully biobased thermoplastic elastomers poly(L-lactide)-b-polymyrcene-b-poly(L-lactide) triblock copolymers with PLLA as hard block and polymyrcene as soft block were synthesized and evaluated. † Abstract Fully biobased poly(L-lactide)-b-polymyrcene-b-poly(L-lactide) triblock copolymers with PLLA as the hard block and polymyrcene as the soft block were synthesized by the ring opening polymerization of L-lactide in the presence of dihydroxyl-terminated polymyrcene precursor and organocatalyst. The copolymer composition and molecular weight of these triblock copolymers were confirmed by NMR and GPC results. Two separated glass transition temperatures were detected by both DMA and DSC techniques, indicating an existence of micro-phase separation in these triblock copolymers, which is a typical characteristic of thermoplastic elastomers with the content of soft block increases. Tensile testing revealed that PLLA-b-PM-b-PLLA (200) having 20 wt% polymyrcene show distinct yielding while other samples fracture at low strain without yielding. POM results indicated that all these spherulites show the same characteristic "Maltese cross" patterns. With the increasing content of polymyrcene, the perfection of spherulites decreases, especially for PLLA-b-PM-b-PLLA (200). Considering the current energy and environmental problems, it is expected that these fully biobased thermoplastic elastomers will be of great significance in expanding the applications of PLLA and solving the ecocrisis around us. a Determined by DMA plots Additionally, TGA is operated to investigate the thermostability and the degradation profile of PLLA-b-PM-b-PLLA triblock copolymers. It is well known that the thermal degradation of polymers may involve thermohydrolysis, zipper-like depolymerization, thermo-oxidative degradation, or transesterification reactions. 22 Fig. 4 displays the TGA and DTG curves of these triblock copolymers at a heating rate of 20 o C min -1 under nitrogen atmosphere range from 50 to 600 o C. As shown in Fig.chain segments at glass transition temperatures, respectively. Furthermore, the corresponding loss modulus and tanδ curve are also featured by two separate peaks, the low temperature peak at -40 o C is related to the glass transition of polymyrcene, while the peak at higher temperature, 67 o C, is the glass transition of PLLA segment. 22,39,40 Therefore, microphase separation is further confirmed. For other two copolymers, DMA curves have been shown in the supporting information ( Fig. S3 and Fig. S4).All plots give the similar trends like that demonstrated in Fig. 5, however, the sample was broken

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A new environmentally friendly and economical recycling process for extracting metals from spent lithium-ion batteries (LIBs) using sulfuric acid and malonic acid as leaching agents is proposed. By applying Box−Behnken design (BBD) and response surface methodology (RSM) optimization techniques, the global optimal solution of the maximum leaching rate of metals in spent LIBs is realized. The results show that under the optimal conditions of 0.93 M H 2 SO 4 , 0.85 M malonic acid, and a liquid/ solid ratio of 61 g•L −1 , a temperature of 70 °C and 5 vol % of 30% H 2 O 2 , 99.79% Li, 99.46% Ni, 97.24% Co, and 96.88% Mn are recovered within 81 min. The error between the theoretical value and the actual value of the metal leaching rate predicted by the regression model is less than 1.0%. Additionally, the study of leaching kinetics reveals that the leaching process of Li, Ni, Co, and Mn in spent cathode materials was affected by the synergistic effect of interfacial mass transfer and solid product layer diffusion. Economic analysis reveals that evaluation index should be fully considered when formulating recovery processes for different metals. This process can reduce the environmental risks of heavy metal disposal and allow the reuse of metals recovered from spent LIBs.