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A series of photosensitive poly(etherester)s containing a,b-unsaturated ketone moieties in the main chain were synthesized from 2,6-bis[4-(3-hydroxypropyloxy)-3-methoxybenzylidene]cyclohexanone (BHPMBCH) and aliphatic and aromatic diacid chlorides. The diol precursor, BHPMBCH, was synthesized from 2,6-bis(4-hydroxy-3-methoxybenzylidene)cyclohexanone and 3-bromo-1-propanol. The solubility of the polymers was tested in various solvents. The intrinsic viscosity of the synthesized polymers, determined by an Oswald viscometer, was found to be 0.06-0.80 g/dL. The molecular structures of the monomer and polymers were confirmed by Fourier transform infrared, ultraviolet-visible, 1 H-NMR, and 13 C-NMR spectral analyses. The thermal properties were studied with thermogravimetric analysis and differential scanning calorimetry. The thermogravimetric analysis data revealed that the polymers were stable up to 220 C and started degrading thereafter. The thermal stability initially increased with increasing spacer length and then decreased due to negative effects of the spacer. The self-extinguishing properties of the synthesized polymers were studied by the determination of the limiting oxygen index values with Van Krevelen's equation. In addition, the photocrosslinking properties of the polymer chain were studied with UV spectroscopy, and we observed that the rate of photocrosslinking increased significantly with increasing methylene carbon chain length of the acid spacer.

New types of mono and bi-functional benzoxazine monomers were synthesized using cardanol (C) and 4-aminobenzonitrile (abn), p-phenylediamine ( ppda) along with paraformaldehyde. The synthesized benzoxazine monomers structure was elucidated by 1H, 13C-NMR and FTIR spectroscopic techniques. The polymerization temperature (Tp) of C-abn and C- ppda are noticed at 280oC and 237oC, respectively. It was also noticed that bi-functional benzoxazine (C- ppda) possesses lower curing temperature than mono-functional benzoxazine (C-abn). The ring opening polymerization of benzoxazine was confirmed by FTIR spectroscopy. Thermal analyses indicate that, benzoxazine [poly(C- ppda)] possesses higher thermal stability than poly(C-abn). The surface roughness of the benzoxazine coated MS specimen was analysed by atomic force microscope. The values of water contact angles obtained for poly(C-abn) and poly(C- ppda) are 145o and 148o, respectively. It was noticed that the mild steel specimen coated with bio-based benzoxazine C-abn exhibit excellent resistance to corrosion.

A metallo-supramolecular polymer poly{4-(((3,4-dihydroxyphenyl) (6-oxidodibenzo[c,e][1,2]oxaphosphinin-6-yl)methyl)amino)phenyl-2,2-dimethylbutanoate} (HP) is synthesized through a Kabachnik-Fields reaction. Then HP is coated on the surface of β-FeOOH by coordination interaction to generate organic-inorganic hybrid β-FeOOH@HP (Fe@P) nanorods, which are used for preparing flame retardant epoxy resin (EP) nanocomposites. The structure of HP is characterized by nuclear magnetic resonance and fourier transform infrared spectroscopy, the morphology and composition of β-FeOOH and Fe@P nanorods are also studied by scanning electron micrograph and transmission electron microscope instruments. With the presence of 2 wt% of Fe@P, the limiting oxygen index value of EP nanocomposite increased to 32.8% with UL-94 vertical burning V-1 rating, and 31.4% of flexural strength enhancement, indicating the improvement of both flame retardant and mechanical properties with low loading amount. The reduction of total smoke production, average CO and CO 2 yield for EP nanocomposites with 0.5 wt% of Fe@P reflected the good smoke suppression. The flame retardant mechanism of Fe@P is also discussed.