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Blends and interpenetrating networks of polychloral with polystyrene, poly (methyl methacrylate), and poly(methyl acrylate) as addition polymers have been successfully prepared in the forms of cylinders (plugs) or of films of 0.03-mm thickness by sequential polymerization. The addition polymers are completely extractable, but about 30% of the polychloral is degraded during the extraction. The polystyrene extracted from the polychloral—polystyrene blends was of relatively low molecular weight. This is attributed to the high chain transfer activity of chloral for styrene polymerization in the presence of chloral. Poly (methyl methacrylate) has a comparable molecular weight, as judged by its inherent viscosity, whether the polymer has been prepared in the presence or in the absence of chloral or polychloral. In the presence of crosslinking agents, divinylbenzene for styrene, and ethylene dimethacrylate for methyl methacrylate, interpenetrating networks of polychloral were obtained; it appears that about 30% of the olefinic polymer (polystyrene) is not crosslinked and can be extracted. Poly(methyl methacrylate) is completely crosslinked. TGA was found to be a simple technique to analyze the composition of the polymer blends.

Dichlorofluoroacetaldehyde was prepared from methyl dichlorofluoroacetate by reduction with lithium aluminum hydride. Highly purified dichlorofluoroacetaldehyde was polymerized using various cationic and anionic initiators to a crystalline insoluble polymer or an amorphous soluble polymer, depending on polymerization conditions. It could be stabilized and the thermal degradation behavior was compared with polymers of other perhaloacetaldehydes. The monomer was also copolymerized with other haloacetaldehydes and phenyl pocyanate.

Head-to-head (H—H) poly(methyl cinnamate) was obtained by alternating radical copolymerization of stilbene and maleic anhydride followed by esterification of the copolymer. The properties of the polymer were compared with head-to-tail (H—T) poly (methyl cinnamate). The H—H polymer was more soluble in organic solvents, had a lower degradation temperature and higher degradation rate than the H—T polymer. On pyrolysis, the main thermal degradation product of H—H and H—T polymers was methyl cinnamate. In addition, H—H poly (methyl cinnamate) gave also small amounts of trans-stilbene and a mixture of dimethyl maleate and dimethyl fumarate.

Anionic chloral polymerization can be carried out under certain circumstances in the presence of acylating agents, such as acetyl chloride and benzoyl chloride. Parts of these polymers exhibit a much improved thermal stability. Introduction of acyl end groups into the polymer permits an estimation of the molecular weight of the polymer. DTG was found to be an excellent technique with which to follow the extent of reaction, to assist in the examination of this kind of end group and to follow the thermal stability of chloral polymers.

Dibromochloroacetaldehyde was synthesized in good yield from chloroacetaldehyde diethyl acetal by bromination. It was purified to give a monomer suitable for homo- and copolymerization. Polymerization could be carried out with anionic and cationic initiators; anionic polymerization gave good yields of a crystalline polymer which could be stabilized. Vacuum degradation of the polymer gave the monomer form quantitatively. The Tcof polymerization (1 M) was -40°C. Dibromochloroacetaldehyde copolymerized with chloral and phenyl isocyanate to insoluble and infusible polymer, but was less reactive than chloral.

Solution polymerization of trioxane (TO) with 1, 3-dioxolane (DO) gave copolymers of various comonomer compositions. TO was also copolymerized with ethyl glycidate (EG) and terpolymerized with DO and EG to polymers of low EG content. The copolymers were acetate-endcapped or base-treated to give stable co- and terpolymers. The treatment of EG containing poly(oxymethylene) (POM) copolymers with sodium hydroxide in methanol at elevated temperatures gave POM ionomers. The polymers were characterized by their infrared and PMR spectra for their general structure and co- and terpolymer composition. POM copolymers with only EG as comonomer showed low base stability but those which contained ethylene oxide (EO), either alone or in combination with EG, gave polymers of high base stability.

?-Alkenonic acids, methyl ?-alkenoates, and methyl ?-epoxyalkanoates of 3 to 11 carbon atoms with –(–CH2–)– spacer groups between the epoxy ring and the carboxyl group have been synthesized and are being characterized. The compounds which have 1, 2, 5 and 8 –(–CH2–)– groups were selected for more extensive studies including polymerization and copolymerization studies. With an aluminumalkyl–water initiator modified with acetylacetone (AlEt3–H2O–AcAc, 1:0.5:1), methyl ?-epoxyalkanoates have been polymerized to polymers of moderate to high molecular weight (for n=8, Mn=2.5×105, and copolymerized with such cyclic ethers as ethylene oxide, propylene oxide, and n-hexene oxide. Investigations of the copolymerizations of ?-epoxyalkanoates with other cyclic ethers and the use of other modified aluminumalkyl–water systems as initiators are now underway. Classical cationic initiators for ?-epoxyalkanoate polymerizations have not resulted in the formation of high polymers although the epoxides were not present after several days of reaction.

Ethyl 4-vinyl-a-cyano-ß-phenylcinnamate was prepared by a five step synthesis from 4-ethylbenzoic acid in an overall yield of 20%. The acid chloride of 4-ethylbenzoic acid was condensed with benzene to 4-ethylbenzophenone. The most critical step in the synthesis was the Knoevenagel condensation of 4-ethylbenzophenone with ethyl cyanoacetate which was accomplished with ammonium acetate as the catalyst. Ethyl 4-ethyl-a-cyano-ß-phenylcinnamate was readily brominated with N-bromosuccinimide and the bromination product, ethyl 4-(1-bromoethyl)-a-cyano-ß-phenylcinnamate was dehydrobrominated. Ethyl 4-vinyl-a-cyano-ß-phenylcinnamate consists of a mixture of cis and trans isomers of nearly equal amounts as indicated in 1H nuclear magnetic resonance and 13C nuclear magnetic resonance spectroscopy. This new monomer was homopolymerized and copolymerized with styrene and methyl methacrylate with radical initiators.