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From solution properties and x‐ray crystallinities of polyvinyl esters and alcohols derived from several vinyl esters polymerized at different temperatures, it is considered that polyvinyl haloacetates are more regular in structure than polyvinyl acetate, but this regularity has not been proved to result from increased syndiotacticity. It has been found that the crystallinities of polyvinyl trifluoroacetates prepared from vinyl‐acetate via polyvinyl alcohols are comparable with those prepared directly from vinyl trifluoroacetate at similar polymerization temperatures. The x‐ray diffraction patterns of polyvinyl acetate prepared from the monomer and of acetylated polyvinyl alcohol obtained by hydrolysis of polyvinyl trifluoroacetate are identical. Likewise, those of polyvinyl alcohols derived from several different vinyl esters cannot be distinguished from one another. Polyvinyl acetates prepared at high and low temperatures and prepared from the trifluoroacetate all hydrolyze in alkaline solution at substantially the same rate. The significant finding in this investigation is that whereas polymerization temperature has a marked effect on the crystallinity of polyvinyl trifluoroacetate, it has little influence on the water solubility of the polyvinyl alcohols. Water solubility is determined by the structure of the monomer from which the polyvinyl alcohol was obtained.