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Star-shaped polyhedral oligomeric silsesquioxane (POSS)-methacrylate hybrid copolymers with phenyl-triazole as terminal groups had been designed and synthesized via sequential atom transfer radical polymerization (ATRP), azidation, and phenylacetylene-terminated procedures, and the hybrid copolymers here could be denoted as POSS-(PXMA-Pytl) 8 , where X can be M, B, L, and S, represented four different methacrylate monomers, such as methacrylate (MMA), butyl methacrylate (BMA), lauryl methacrylate (LMA), and stearyl methacrylate (SMA), respectively. Thermal gravimetric analysis (TGA) and in situ Fourier transform infrared spectroscopy (FTIR) were applied for studying the thermal stability and degradation mechanism, and it was found that all of the POSS-(PXMA-Cl) 8 and POSS-(PXMA-Pytl) 8 copolymers exhibited excellent thermal stabilities, which had great potential in heat-resistant material application. Different tendencies of decomposition temperatures at 5% and 10% weight loss (T 5 and T 10 ) dependent on the side-chain length and terminal group species were investigated respectively. The longer alkyl side chains of the monomers, the lower thermal stabilities, and enhanced T 5 and T 10 were also shown with the introduction of phenyl-triazole groups instead of chlorine groups.

The aggregation behavior of three tadpole-shaped Polyhedral oligomeric silsesquioxane (POSS) based block copolymers using different blocks poly(methyl methacrylate) (PMMA) and poly(trifluoroethyl methacrylate) (PTFEMA) with different block sequence and ratio (POSS-PTFEMA 161 -b-PMMA 236 , POSS-PMMA 277 -b-PTFEMA 130 , and POSS-PMMA 466 -b-PTFEMA 172 ) was investigated on the air-water interface. The interfacial rheology of three block copolymers was studied by surface pressure isotherm, compression modulus measurements, and compression and expansion hysteresis analysis on the Langmuir trough. The block sequence and ratio play a great role in self-assembly behavior at the interface. Based on surface pressure isotherm analysis, a thin film with low elasticity was achieved for the POSS-PTFEMA 161 -b-PMMA 236 . Moreover, for the block copolymer with same segment sequence (POSS-PMMA 2 -b-PTFEMA), the thin film compression capability is increased with increasing the PMMA ratio. The morphology of the deposited LB thin film was illustrated by atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS). We observed that a thin film was composed by crater-shaped quasi-2D micelles for POSS-PTFEMA-b-PMMA, while it was proved that only flaky texture was observed for both POSS-PMMA 277 -b-PTFEMA 130 and POSS-PMMA 466 -b-PTFEMA 172 . The thickness and area of flaky aggregates were greatly related to PMMA ratio. The different interface self-assembly structure evolution was proposed based on the interfacial rheology and thin film morphology studies.