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Blends of poly(ɛ-caprolactone) with either head-to-head or head-to-tail poly (vinyl chloride) were prepared by solvent casting in the form of films and their glass transition temperatures were determined by DSC analysis. The DSC scans of the blends of both poly(vinyl chloride) isomers were very similar. For blends containing 25% and 50% of poly(ɛ-caprolactone), a single transition step, a Tg, was observed, whereas for a blend containing 75% of poly (ɛ-caprolactone) three transition steps were observed, one glass transition and also a crystallization and a melting transition.

2-(2,4-Dihydroxyphenyl)2H-4-methoxybenzotriazole was treated with acryloyl or methacryloyl chloride and gave 2[2-hydroxy-4-acryloxy(methacryloxy)phenyl]2H-4-methoxybenzotriazole. The two monomers were homo-polymerized and copolymerized with styrene, methyl methacrylate and n-butyl acrylate with azobisisotutyronibrile as the initiator. The monomers, homopolymers and copolymers were characterized.

The 13C NMR spectra of H-H PS and H-H PVCH show the influence of the long range order on the chemical shift of several carbons. There is some hope to improve the resolution by the choice of appropriate solvents. The attribution of the lines to specific stereosequences would require the preparation and separation of optically pure dimers and trimers. It is, however, already possible to compare the microstructure of H-H polymers prepared by different chemical ways.

Regular aliphatic/aromatic copolyoxamides were prepared from diamine-oxamides and aromatic diacid chlorides by interfacial and solution polymerization. Solution polymerization in chloroform or dimethylacetamide is preferred for the preparation of large quantities of polymers but interfacial polymerization is most conveniently carried out for the preparation of polymers with high molecular weight. Aromatic diacid chlorides used included the diacid chlorides of terephthalic acid, isophthalic acid, 2,6-pyridinedicarboxylic acid, two isomeric naphthalene dicarboxylic acids, two cyclo-hexanedicarboxylic acid isomers, as well as 1,1-cyclobutane-dicarboxylic acid. Copolymers of diamine-oxamides with mixtures of acid chlorides of isophthalic and pyridine dicarboxylic acid and isophthalic acid/tetrachloroterephthalic acid have also been prepared. Most polymers are film-forming and are soluble in concentrated sulfuric acid, trifluoroacetic acid, and dimethylacetamide (containing several per cent LiCl). A number of these polymers gave dense or asymmetric membranes, particularly the polymers from ethylene diamine as the aliphatic diamine, particularly poly(iminoethyleneimino-oxalyliminoethyleneiminoisophthaloyl) (p-222I). Diamine oxamides with more than two amide groups in the molecules have been prepared, and in one case polymers with aromatic diacid chlorides have been prepared by interfacial polymerization. All regular aliphatic/aromatic copolyoxamides are high-melting and generally decompose above 350°C without melting. They can, however, be fabricated from solution into brittle fibers or into desalination membranes.

Tetrachloroethylene oxide has been synthesized by direct oxidation of tetrachloroethylene with oxygen in the presence of ultraviolet light. This preparation resulted in a mixture of tetrachloroethylene oxide and trichloroacetyl chloride in approximately equal amounts under the most favorable conditions. Tetrachloroethylene oxide rearranges readily to trichloroacetyl chloride above 60 C with an activation energy E of 3.0 × 104 cal/mole and a pre-exponential factor A of 1.9 × 1013. All attempts to polymerize tetrachloroethylene oxide under a variety of conditions failed.

Anionically polymerized poly-n-heptaldehyde (PHA) has been studied by wide-angle x-ray diffraction, and a tetragonal unit cell is proposed. DSC studies reveal several endotherms due to side-chain melting with a pronounced dependence upon annealing.

Hexa-n-propyl orthoisophthalate, hexa-n-propyl orthoterephthal-ate, and in one case hexaethyl orthooxalate were condensed with aminomalondiamine dihydrochloride or aminomalonamideamidine dihydrochloride in DMSO or DMF between 100°C and the boiling point of DMF to oligomers containing adenine and hypoxanthine rings. For example, hexa-n-propyl orthoisophthalate and amino-malonamidamidine dihydrochloride in dimethyl sulfoxide at 100°C gave an oligomer of poly (2,8-hypoxanthinediyl-1,3-phenylene). The condensation was limited to oligomers of relatively low molecular weight, partly because of the low solubility of the oligomers under reaction conditions and partly also because the four reactive amino groups of the aminomalonamideamidine and the aminomalondiamidine did not react simply as difunc-tional tetramines to form linear aromatic polymers; this unequal reactivity of the amine functions caused side reactions to occur. Such side reactions have not been observed in the reactions of bisorthoesters with tetrafunctional aromatic orthodiamines, such as 3,3',4,4'-tetraaminobiphenyl.

Cyclic trimers of n-nonaldehyde (NA), n-decaldehyde (DA), n-undecaldehyde, (UA) and n-dodecaldehyde (DDA) were prepared by reacting the individual aldehydes with protic or Lewis acids. Higher aliphatic aldehydes whose long paraffinic chains dominate the general properties of these compounds do not trimerize readily the trimers, when formed, are purified with difficulty. The cyclic trimers, characterized by IR and NMR spectroscopy, are exclusively the cis isomers and commonly exist in all equatorial conformations. The melting behavior of the cyclic trimers was studied by DSC. The melting endotherms and the enthalpies of fusion increase with increasing chain length. Although the melting temperatures of the cyclic trimers are similar to the melting range of the side-chain crystallization of the corresponding crystalline isotactic polyaldehydes, the transition peaks of the trimers are single peaks and much sharper than the corresponding polymer peaks.

Endcapping of oligo(oxyethylene) glycols was carried out by transesterification of methyl N,N-dimethylaminobenzoate with sodium methoxide as the catalyst or by the reaction of sodium salicylate with the ditosyl ester of the oligo(oxyethyl-ene) glycols. Several other common reactions were tried for the endcapping of the oligo(oxyethylene) glycols but were found to be either more cumbersome or unsuccessful. All products were obtained in high yield and high purity. The reactions of tetraalkylammonium carboxylates with aliphatic halides were found to be very general and mild reactions for the preparation of esters in high yield and high purity. It was found that these reactions could be utilized for the preparation of esters on polymers even if the carboxylate group was directly attached to the polymer chain. It was also demonstrated that the aliphatic halide group could be on the polymer, as in the case of polyepichlorohydrin. Copolymers of epichlorohydrin and glycidyl N,N-dimethylaminobenzoate with up to 90% glycidyl benzoate as the comonomer were prepared, and poly(tetra-butylammonium methacrylate) was effectively transformed with 4-(2-bromoethoxy)-2-hydroxybenzophenone into the corresponding ester. The products were characterized by the usual spectral means.

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.

Summary We have demonstrated that optical circular dichroism (CD) measurements can be carried out on powders suspended in a liquid medium. The refractive indices of the powder and the suspending liquid must be matched, the suspending liquid must not interact significantly with the solid to be measured and must not absorb in the region where the measurements are carried out. Sodium thioantimonate nonahydrate (Na3SbS4·9H2O) powders obtained by grinding oflevo- ordextro-rotatory crystals were found to be excellent examples for the demonstration of this technique. Measurements of the optical rotation forlevo- anddextro-rotatory crystals and powders of Na3SbS4·9H2O were also carried out and provided additional characterization of this salt. In the course of developing the CD measurement technique, CD of NaClO3 and NaBrO3 crystals was also measured.

The crystallization of agitated aqueous solutions of sodium chlorate and sodium bromate was nucleated with levo- or dextrorotatory crystal powders of sodium chlorate and sodium bromate to furnish new crystals with a high degree of chiroptical purity.

Plastics used in outdoor applications are exposed to the harmful solar radiation between 290 and 400 nm. Fortunately, the ozone layer of the outer atmosphere protects the earth's surface from the higher energy radiation below 290 nm. The intensity of solar radiation at the surface of the earth is at a maximum in July and a minimum in January due to changes in the thickness of the ozone layer. The intensity also varies with the time of day, location, and weather conditions.

A number of new polymers have been studied. They include polymers obtained by chain reaction polymerization of olefins and epoxides with functional groups where the polymerizable group was separated from the functional group by an inert spacer group, the preparation of head-to-head polymers, and the preparation of optically active polymers based on the macromolecular asymmetry.

Several structural isomers of vinylsalicylic acid and the corresponding methyl vinylsalicylates have been synthesized in this laboratory previously and have been polymerized and copolymerized with methacrylic acid and with methyl methacrylate. The monomer-ic as well as the polymeric compounds have been tested for their antimicrobial and cytotoxic properties. This article also deals with the sunscreening properties of some polymeric salicylic acid derivatives and their possible use as the effective ultraviolet-absorbing agent in skin protection formulations. The results show that making homopolymers and especially copolymers is a way of increasing one property and decreasing another, making new compounds with more specific properties.

Investigations of the anionic polymerization of acrylonitrile in dimethylformamide initiated with 14C-labeled lithium tertiary butoxide have shown that the tertiary butoxide group is not incorporated into the polymer chain, Comparison with the initiation behavior of other lithium alkoxides has indicated that the amount of incorporation of the alkoxyl groups from the anionic lithium alkoxide initiators depended on the basicity of the alkoxide group. A new initiation mechanism is proposed which involves as initiator an active center which consists of an electron donor-acceptor complex of the lithium alkoxide with the solvent dimethylformamide and the acrylonitrile monomer.

Polybenzoxazoles of relatively low molecular weight have been prepared from hexa-n-propylorthoisophthalate in DMSO at 100°C. Unlike the preparation of polybenzimidazoles via the same route which gave high molecular weight linear polybenzimidazoles, condensation of dihydroxy-diaminobiphenyl with bisorthoesters gave only polymers of low molecular weight. It has not been established but it is most likely that the formation of only low molecular weight polymers was caused by the low basicity of the aromatic amino groups. Benzimidazoles of low molecular weight had also been observed when aromatic tetramines of low basicity were used for the condensation with bisorthoesters.

Thermal stability of samples of polychloral prepared with different initiators and treated with various endcapping agents was studied using differential thermogravimetric analysis (DTG). Four temperature regions at which maxima of DTG curves occur were identified. On the basis of the known mechanism of initiation and the possible mechanism of termination, the structures of both initial and terminal endgroups of individual polychloral samples were elucidated which enabled the identification of the specific temperature region of thermal degradation of polychloral molecules having a specific type of endgroup. These results were confirmed by studies of the DTG curves of chloral-isocyanate copolymers containing stable terminal fragments with a high content of urethane linkages.

Chloral polymers prepared by anionic polymerization have alkoxide endgroups as terminal ends at the end of this polymerization. The initiating anion has, as expected, no influence on the type of terminal group formed. Polychloral with terminal alkoxide ends degrades easily thermally to monomeric chloral. Alkoxide endgroups in polychloral do not readily react with alkylating or acylating agents, although partial stabilization has been observed when alkoxide-terminated polymers were allowed to stand for periods of time; the endgroups seem to react either with impurities or with excess chloral in side reactions. With protic acids, alkoxide-terminated polychloral is transformed into hydroxyl-terminated polymer of higher thermal stability. Studies of the initiation step of the chloral polymerization revealed that above the ceiling temperature of polymerization, strong nucleophiles, such as soluble tertiary butoxide, initiate quantitatively, but polymerization does not proceed until the mixture is cooled. When chloral is initiated with weaker nucleophiles such as chloride or carboxylates, the initiation equilibrium is not on the side of the initiated species, although it shifts effectively as polymerization proceeds; with carboxylates as initiators the ester group has been found incorporated as the initial endgroup in polychloral. With sufficient amounts of lithium tertiary butoxide as anionic initiator, polychloral of low molecular weight was prepared. This polymer does not react with end-capping reagents (other than PCl5) as does high molecular weight polychloral; in spite of considerable effort it was not possible to prepare low molecular weight soluble polychloral or oligomeric polychloral. Polychloral prepared with cationic initiators is thermally more stable than unstabilized anionically initiated polychloral but is generally crumbly and incoherent. The end-groups of such polymers are usually hydroxyl endgroups. Identification of endgroups of the polymers has been done where possible by IR spectroscopy, for the initiation reaction by NMR spectroscopy, but for high molecular weight insoluble polymers almost exclusively by comparative thermal polymer degradation.

?-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.

Blends of head to head polyisobutylene and amorphous head to tail polyisobutylene were prepared by casting films of the polymer mixtures from o-dichlorobenzene. The glass transition behavior of the polymer blends was studied by DSC analysis. Two glass transition temperatures were observed over almost the entire composition range which indicates that the two structurally similar head to tail and head to head polyisobutylenes are not miscible even in the molecular weight range of 3000 to 5000.

Copolymerization of 2, 3-dimethylmaleic anhydride was accomplished with vinyl ethers, particularly n-butylvinyl ether and isobutyl-vinyl ether and gave exactly alternating copolymers in all proportions of feed comonomer compositions. 2,3-Dimethylmaleic anhydride has not yet been copolymerized with vinyl comonomers with less electron donating properties.

Ionic polymerization received prominence about 35 years ago when isobutylene was commercially polymerized by two processes which, with some modifications, are still used today [1]. One process uses aluminum chloride as the initiator and the other uses boron trifluoride; both cationic polymerization processes are carried out at low temperatures. A number of additional commercial processes based on cationic and anionic polymerization have since been developed. Cyclic ethers, most prominently tetrahydrofuran, are polymerized cationically to relatively low molecular weight hydroxyl terminated polyethers which have found important uses in polyurethanes. Trioxane is copolymerized with a small amount of ethylene oxide to form a useful copolymer of polyoxymethylene. Other products which are of interest are the polymers of caprolactone and epichlorohydrin and polymers of various epoxides, mainly those of glycidyl ethers which are most commonly known as epoxy resins. Anionic polymerization on a commercial scale has developed along the lines of styrene and isoprene polymers. Stereorubber, stereoregular 1,4-cis isoprenes, are based on lithium initiators and were introduced in the middle 1950s. Triblock polymers based on A-B-A block polymers of isobutylene with styrene as endblocks and prepared from living polymers have been known since the early 1960s.

Alternating copolymers of cis-butene-2 and maleic anhydride were esterfied to the methylester which corresponds to head to head (H-H) poly(methyl crotonate).The chemical, physical, and mechanical properties and thermal degradation behavior of H-H poly (methyl crotonate) was studied and compared with the properties of head to tail (H-T) poly(methyl crotonate). This latter polymer was made by a known anionic polymerization technique and was, unlike the amorphous H-H polymer, partially crystalline. The Tg of H-H polymer was found to be higher than that of the H-T polymer. Thermal degradation behavior of H-H and H-T polymer was between the degradation behavior of H-H and H-T poly(methyl cinnamate) and poly (methyl acrylate). Poly (methyl crotonates) degraded to a substantial part to small molecules and char; methyl crotonate was found among the degradation products. H-H Poly (methyl crotonate) gave also butene-2 and a mixture of dimethyl maleate and dimethyl fumarate on pyrolysis.

Head-to-head poly(methyl acrylate) was prepared by esterification of the known alternating copolymer of ethylene and maleic anhydride. Some of the chemical,physical, and mechanical properties and the thermal degradation behavior of head-to-head poly(methyl acrylate) were studied and compared with those of head-to-tail poly(methyl acrylate). The Tg of the head-to-head polymer was higher than that of the head-to-tail polymer, but the solubilities of both types of polymers of comparable molecular weight were similar. Head-to-head poly(methyl acrylate) degraded thermally at approximately the same temperature and with a rate similar to head-to-tail poly(methyl acrylate). Unlike poly(methyl cinnamates) which cleanly degraded to monomers, poly(methyl acrylates), head-to-head and head-to-tail, degrade to very small molecules, such as CO2, methanol, but also larger polymer fragments and char. Trace amounts of monomers (methyl acrylate) were also observed.

It was demonstrated that highly hindered bisphenols could be used to produce polyesters of moderate molecular weight. Bisphenols linked in the 4 and 4' or the 2 and 2' positions and substituted in positions ortho and para to the phenolic hydroxyl groups with methyl or tertiary butyl groups (these bisphenols are now used as very effective antioxidants) formed polymers, their reactivity depending more on the nature of the group linking the two phenyl rings than on the steric effects of the ortho substi-tuents. Bisphenols linked in the 2 and 2' positions and containing bulky electron-withdrawing groups were found to be least effective as condensation monomers although successful polymerization to moderate molecular weight could be achieved using me it polycondensation techniques.