A series of main-chain thermotropic liquid crystalline polyesters were synthesized by polycondensation from mesogenic dial as 4,4'-bis(6-hydroxyhexyloxy)biphenyl (BHHBP) and various diacids with different substituents as succinic acid (no side group), 2-methylsuccinic acid (aliphatic side group) and 2phenylsuccinic acid (aromatic side group), named as poly(4,4'-bis(6-hydroxyhexyloxy)biphenyl succinate) (PBDS), poly(4,4'-bis(6-hydroxyhexyloxy)biphenyl methylsuccinate) (PBDMS), poly(4,4'-10 bis(6-hydroxyhexyloxy)biphenyl phenylsuccinate) (PBDPS), respectively. Liquid crystalline behaviours were investigated through differential scanning calorimetry (DSC), polarizing optical microscopy (POM) and small angle scattering (SAXS) and thermal stability of the polyesters was determined via thermogravimetric analysis (TGA). PBDS, PBDMS and PBDPS showed a SmF, SmB and SmA phase, respectively. With enlarging the side group, the d-spacing of the smectic layer increased, indicating a 15 folding packing of the polymer chains. Therefore, the adjacent phenyl rings in side groups stacked well together and formed strong π-π interaction even when the temperature was higher than T i .The special structure of PBDPS could endow the good mechanical property. Thus, PBDPS had the maximum tensile stress (28.6 MPa) and the highest elongation at break (1060 %). Furthermore, the strong π-π interaction can act as netpoints, therefore, PBDPS exhibited excellent shape fixing (>99 %) and shape recovery ratio 20 (>99 %) with large strain (>220 %). 65 question may be put forward: can these π-π interactions be strong enough to act as netpoints in a shape memory liquid crystalline polymer? If the answer is positive, the structural design of TLCP is very important.

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Rechargeable Li-I2 battery has attracted considerable attentions due to its high theoretical capacity, low cost and environment-friendliness. Dissolution of polyiodides are required to facilitate the electrochemical redox reaction of the I2 cathode, which would lead to a harmful shuttle effect. All-solid-state Li-I2 battery totally avoids the polyiodides shuttle in a liquid system. However, the insoluble discharge product at the conventional solid interface results in a sluggish electrochemical reaction and poor rechargeability. In this work, by adopting a well-designed hybrid electrolyte composed of a dispersion layer and a blocking layer, we successfully promote a new polyiodides chemistry and localize the polyiodides dissolution within a limited space near the cathode. Owing to this confined dissolution strategy, a rechargeable and highly reversible all-solid-state Li-I2 battery is demonstrated and shows a long-term life of over 9000 cycles at 1C with a capacity retention of 84.1%.

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