Ring opening metathesis polymerization of polyoctahedral oligomeric silsesquioxanes (POSS) incorporated oxanorbornene-5,6-dicarboximide: Synthesis, characterization, and surface morphology of copolymers

The synthesis and characterization of N-propyl-POSS-7-oxanorbornene-5,6- dicarboximide (NPONDI) and N-3-(trifluoromethyl)phenyl-7-oxanorbornene-5,6- dicarboximide (TFNDI) was reported. The synthesis of the POSS-based (co)polymers were accomplished by ring opening metathesis polymerization (ROMP). The monomers and polymers were characterized using FT-IR, ¹H-, ¹³C-, ²⁹Si-NMR, and GPC techniques. Thermal properties of TFNDI-NPONDI copolymers were evaluated by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). Transmission electron microscopic (TEM) analysis of optically transparent and flexible copolymer films revealed the presence of 50nm-sized POSS agglomerates. Atomic force microscopy analysis of the film surface exhibited a modest increase in surface roughness of TFNDI-NPONDI copolymers as compared with homopoly[N-3(trifluoromethyl)phenyl-7- oxanorbornene-5,6-dicarboximide] (HTFNDI). The POSS incorporated polymers such as 1NPONDI, 2NPONDI, and 3NPONDI increased the hydrophobicity as compared with HTFNDI. This was measured by static contact angle analysis. The study focussed on the dispersion, surface morphology, and the microstructure of POSS in TFNDI-NPONDI copolymer as determined by scanning electron microscopy (SEM).