Soluble copolymers of diethyl 2‐(methacryloyloxy) ethyl phosphate (DMP) with methyl methacrylate (MMA), methyl acrylate (MA), ethyl acrylate (EA) and butyl acrylate (BA) were synthesized by radical copolymerization in benzene solution using azobis(isobutyronitrile) (AIBN) as initiator. The monomer reactivity ratios of these systems at 60°C were determined by the conventional schemes using the methods of Fineman–Ross, Joshi‐Joshi, and Kelen–Tüdos. DMP underwent a completely random and azeotropic copolymerization with MMA whereas in its reaction with the other acrylates DMP entered preferentially into the polymer chain. The reactivities of DMP‐terminated polymer radicals towards the acrylate monomers were found to be in the order: MMA > EA > MA > BA. An increase in solvent polarity decreased the relative reactivity of DMP for the DMP‐MMA pair. An examination of the molecular weights of the copolymers revealed the occurrence of chain transfer caused by DMP. The copolymer glass transition temperatures were determined and the variations of Tg with copolymer compositions were discussed according to the theory of Johnston, taking into account the effect of the sequence distributions of the comonomers on Tg. The Tgs of the alternating copolymers of DMP with the four alkyl acrylates were calculated.

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α,ω‐Dihydroxy‐terminated‐PMMA was synthesized by the bulk polymerization of methyl methacrylate in the presence of a functional “iniferter,” viz., N,N′‐diethyl‐N,N′‐bis(2‐hydroxyethyl)thiuram disulfide (DHTD). The kinetics of the polymerization were studied by determining the polymerization rate as a function of the “iniferter” concentration at 60, 70, 85, and 95°C. Evaluation of the data by a computerized multiple regression analysis led to calculation of the various kinetic parameters and the activation energies of the related phenomena. The maximum observed in the Rp–initiator concentration curve was found to shift to lower initiator concentration as the temperature increased. The formal reaction order with respect to the concentration of the initiator decreased with increasing temperature and concentration of DHTD. The chain transfer constants of DHTD with MMA were calculated from the molecular weights of the resulting polymers. The functionalities of the oligomers were calculated from the elemental analysis of the chain end groups. Thermogravimetric analysis revealed that the polymer chain ends were devoid of unsaturated groups and that the polymer underwent degradation only by random scission.

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