The monomer 2,4-dichloro phenyl acrylate (2,4-DCPA) was synthesized from 2,4-dichlorophenol and characterized by conventional methods. The homopolymers of 2,4-DCPA and its copolymers with 8-quinolinyl methacrylate (8-QMA) in different feed ratio were prepared by free radical polymerization using dimethyl formamide (DMF) as a solvent and 2,2'-azobisisobutyronitrile (AIBN) as an initiator. The resulting polymers were characterized by Infrared Spectroscopy. UV spectral data were employed to obtain the reactivity ratios of the monomers, 2,4-DCPA and 8-QMA. The results showed that 2,4-DCPA is more reactive than 8-QMA. Average molecular weights and intrinsic viscosities determined by Vapour pressure osmometer (VPO) lies in the range of 7900 to 10890 and 0.021-0.036 dl.g -1 respectively. Thermal analysis shows that thermal stability of copolymers increases with the increase of 2,4-DCPA. The copolymers also showed antimicrobial activity which increased with increase in 8-QMA content.

Low molecular weight polyketones were prepared by the Friedel‐Crafts reaction from p‐cresol, chloroacetylchloride and dichloroalkanes, i. e. dichloromethane and 1,2‐dichloroethane. The polyketones were characterized by IR spectra and vapour pressure osmometry. The thermal properties were studied by thermogravimetry and differential scanning calorimetry. The kinetic parameters for the thermal decomposition reaction were evaluated by the methods of Broido and Doyle. The polyketones were found to be thermally stable up to 200°C. They show antimicrobial properties against bacteria, fungi and yeast.

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A series of novolak type resins were prepared by reacting formaldehyde with various phenoxy acetic acids using HCl as catalyst. All the synthesized resins were characterized by spectral studies (IR), viscometric measurements and by estimating the numberaverage molecular weight by vapour-pressure osmometry. Two of these resin samples were used as curing agents for epoxy resins for studying the kinetics of curing by DSC technique. The cured epoxies were tested for thermal stability. These resins impart very good heat resistance to epoxy systems. ZUSAMMENFASSUNGEine Reihe von Harzen des Novolak-Typs wurden durch Reaktion von Formaldehyd mit verschiedenen Phenoxy-Essigsauren hergestellt, indem HCl als Katalysator eingesetzt wurde. Alle synthetisierten Harze wurden IR-spektroskopisch und viskosimetrisch untersucht; das zahlenmittlere Molekulargewicht wurde mit Hilfe der Dampfdruckosmometrie bestimmt. Zwei der Harzproben wurden zum Vernetzen von Epoxidharzen eingesetzt, um die Kinetik der Vernetzung mittels DSC-Untersuchungen zu studieren. Die vernetzten Epoxide wurden hinsichtlich ihrer thermischen Stabilitat gepriift. Die hergestellten Harze verleihen dem Epoxidsystem eine sehr gute Hitzebestandigkeit.

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