The cardanol formaldehyde resin (CFR) has been synthesized by the condensation of cardanol with formaldehyde (ratio of 1:0.7) in the presence of oxalic acid catalyst. Synthesized CFR was epoxidized using epichlorohydrin (ECH) with 1:10 molar ratio. Cardanol was also directly epoxidized using ECH with the above-mentioned ratio. Synthesized resins have been characterized by Fourier-transform infrared and nuclear magnetic resonance spectroscopic analyses. Thermal properties have been studied by thermogravimetric analysis. Decomposition kinetics have been studied by various kinetic models of the synthesized compounds. In the present study, Horowitz-Metzger, Broido and Coats-Redfern models have been used to calculate the activation energy (E a ), pre-exponential factor (A) and rate constant (K). E a calculated from all the three models mentioned above was close to each other.

Four series of photocrosslinkable-cum-flame retardant poly(benzylidene phosphoramide ester)s were synthesized from bis(4-hydroxy-3-methyoxybenzylidene) acetone, 2,5-bis(4-hydroxy-3-methoxybenzylidene)cyclopentanone, 2,6-bis(4-hydroxy-3methoxybenzylidene)cyclohexanone and 2,7-bis(4-hydroxy-3-methoxybenzylidene) cycloheptanone with various arylphosphorodichloridates by interfacial polycondensation using a phase transfer catalyst. The resultant polymers were characterized by gpc, FTIR, 1 H, 13 C and 31 P-NMR spectroscopy. Thermal behavior of the polymers was evaluated by differential scanning calorimetry and thermogravimetry. Flame retardant properties were ascertained by Limiting Oxygen Index. The photocrosslinking ability of the polymers was studied by ultraviolet spectroscopy. The crosslinking proceeds via 2 ϩ 2 cycloaddition reaction of the benzylidene groups. The rate of crosslinking decreases with increase in the size of cycloalkanone ring, while the thermal stability increases with increase in the size of the alkanone ring.

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A new class of poly ( benzylidene phosphoramide ester ) s containing a photoreactive benzylidene chromophore in the main chain were synthesized from bis(4-hydroxy-3-methoxy benzylidene)acetone with various substituted N-aryl phosphoramidic dichlorides by an interfacial polycondensation technique. The synthesized polymers were characterized by inherent viscosity, IR, and 1 H-, 13 C-, and 31 P-NMR spectroscopy. The molecular weights of these polymers were determined by gel permeation chromatography. These polymers were studied for their thermal stability and photochemical properties. Thermal properties were evaluated by thermogravimetric analysis and differential scanning calorimetry. It was found that halogen-containing polymers show a higher thermal stability than that of nonhalogenated polymers. The photocrosslinking property of these polymers was studied by ultraviolet spectroscopy. The photoreactive benzylidene chromophore in the main chain dimerizes via 2p / 2p cycloaddition reaction to form a cyclobutane derivative and leads to crosslinking.

A photosensitive epoxy resin was synthesized from bis(4-hydroxy -3-methoxy benzylidene) acetone and epichlorohydrin using solution polycondensation method. The prepared epoxy resin was characterized by UV, IR, 1 H NMR, and 13 C NMR spectroscopy. The thermal stability of the epoxy resin was assessed by thermogravimetric analysis. The glass transition temperature of the polymer was determined by differential scanning calorimetry. The photocrosslinking property and photopolymerizing ability of the epoxy resin were studied in film and solution state using UV spectroscopy. The effect of photo acid generator and sensitizer on photosensitivity of the resin was also investigated.