Cinnamic acids have been prepared in moderate to high yields by a new direct synthesis using aromatic aldehydes and aliphatic carboxylic acids, in the presence of boron tribromide as reagent, 4-dimethylaminopyridine (4-DMAP) and pyridine (Py) as bases and N-methyl-2-pyrolidinone (NMP) as solvent, at reflux (180-190°C) for 8-12 hours.

A series of new aromatic polyamides containing cinnamide pendent units were prepared from 2 0 -(cinnamide)ethyl-3,5-diaminobenzoate and various aromatic dicarboxylic acids by the direct polycondensation reaction, with triphenyl phosphite and pyridine as condensing agents. The polyamides were characterized by 1 H NMR, IR, and UV spectroscopy, and gel permeation chromatography. Their thermal stability was studied by thermogravimetric analysis in air, and differential scanning calorimetry. These polymers were readily soluble in polar aprotic solvents and can be cast from their solutions in flexible and tough films. Glass transition temperatures (T g s) of these polyamides were observed in the range of 225-2458C. Their inherent viscosities varied from 0.77 to 1.12 dL/g that corresponded to weight-average and number-average molecular weights of 39,000-72,700 and 18,800-29,000, respectively. These polymers can be photochemically crosslinked. The photochemical aspects were revealed by means of UV-vis and IR analyses onto thin films.

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Polymeric allyl pyridinium salts were synthesized from styrene and 4-vinyl pyridine copolymers by quaternization and counteranion exchange reactions. The initiation capability of these copolymers, in conjunction with a photochemical free radical source such as benzoin, via an addition ± fragmentation mechanism in the cationic polymerization of cyclohexene oxide is investigated.

Aromatic polyamides containing chalconyl substituted m-phenylenediamine segments Summary-4'(β-hydroxyethoxy)chalconyl-3,5-diaminobenzoate and three kinds of aromatic dicarboxylic acids were used as monomers in a direct polycondensation reaction for synthesis of some polyamides containing chalconyl units in pendant groups. The presence of these units in the structure of polyamides renders them photoreactive and this property was monitored by UV and IR spectroscopy. The polyamides show good thermal stability, glass transition temperature (Tg) values around 230 o C and inherent viscosity in the range of 0.67-0.79 dLg-1 .