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Stereospecific polymerization of vinyl alkyl ether was studied; various kinds of compounds, such as metal oxides, metal halides, metal oxyhalides, metal sulfate complexes and organometallic compounds-Lewis acid complexes, being used at low temperature or room temperature. The relationship between the structures of catalysts and the stereoregularities of polymers is discussed, and it is found that tetrahedral compounds which have one active edge are especially useful for making the stereoregular polymers at room temperature. Also, the shorter the length of active edge, the more suitable the catalyst is for stereospecific polymerization. On the basis of these experimental results, a mechanism of stereospecific polymerization of vinyl alkyl ether is proposed.

The rate of polymerization of t-BuEO by t-BuOK in DMSO is about one-tenth that of propylene oxide. The slow rate of propagation was accompanied by considerable chain transfer. In the absence of solvent, the polymer obtained was crystalline, different from the isotactic form and therefore must be syndiotactic. The NMR spectra indicate the isotactic polymer exists in solution preferentially in the skew1 form, while syndiotactic is about 60% skew1, 40% skew2. Amorphous polymer accompanying isotactic exists about 50% in the trans conformer, by NMR data.

An attempt was made to summarize the activity of magnesium halides in the polymerization of vinyl ethers. Bulk polymerization was carried out at temperatures of 0–80°C. Methyl, ethyl, isopropyl, and isobutyl vinyl ethers were used as monomers, and the relative reactivities of these monomers were compared. Except for the fluoride, magnesium halides had mild activity. Within a given group, the overall activation energies of polymerization decrease with increasing weight of halogen. On the other hand, the molecular weight of polyvinyl ethers obtained from this group of catalysts increases with decreasing weight of halogen. In addition, some differences were observed between the diethyl ether complex and the dioxane complex of magnesium bromide.

Magnesium compounds, especially Grignard reagents were studied as catalysts in the polymerization of vinyl ethers. The Grignard reagent and diethyl magnesium possessed no activity for polymerization of vinyl ether. However, if the Grignard reagent is combined with some sort of third substances, it shows good activity. For these substances, oxygen, aldehydes, some metal oxides, and halogenated hydrocarbons seemed to be effective. The molecular weight of the polyvinyl ether obtained from this combined catalyst system is markedly higher than those of polymers obtained with the Friedel-Crafts type of catalyst, but the polymer of vinyl ether obtained from this mixed catalyst possesses little crystalline structure. The possible mechanism of the polymerization with this mixed catalyst is thought to be a cationic initiation type, because the true active species are regarded to be intermediate compounds which are analogous to magnesium halides or alkoxymagnesium halides. In this connection, alkoxymagnesium halides and magnesium oxide were examined. They had a good activity for polymerization but did not yield a high polymer.

Optical constants of several optical glasses and fused quartz between 7 and 23 eV are reported. After a brief description of the method of determining optical constants from the reflectances measured at two or more angles of incidence and the graphical analysis of data, the results are given in terms of n, k, n 2-k 2, and n kν, with some remarks on their accuracies. An absorption band was observed at about 14 eV in the fused quartz and two of the glasses examined and has been tentatively assigned to the characteristic electronic transition of SiO2.