Abstract: There is disclosed a composition which comprises an aqueous emulsion selected from (A-1) aqueous emulsion comprising a dispersoid which comprises a vinyl ester polymer (1) and a copolymer a (meth)acrylic ester and a primary hydroxyl group-containing ethylenically unsaturated monomer (2), the polymer (1) being present principally in the central part of the dispersoid, the copolymer (2) having a glass transition temperature of lower than 50.degree. C. an being present principally in the peripheral part thereof; and a dispersant comprising a vinyl alcohol polymer and (A-2) aqueous emulsion comprising a dispersoid which comprises a copolymer of a hydrophobic unsaturated monomer such as (meth)acrylic ester and a primary hydroxyl group-containing ethylenically unsaturated monomer; and a dispersant comprising a vinyl alcohol polymer having a mercapto group at an end thereof and a (B) polyvalent isocyanate compound.

Abstract: Provided is a process for producing molded articles having excellent flexural strength, flexibility and dimensional stability, which comprises autoclave-curing at not lower than 100.degree. C. an aqueous composition comprising a hydraulic material (A) and a polyvinyl alcohol (B) powder, said polyvinyl alcohol (B) powder being contained in an amount of 0.1 to 20% by weight based on the weight of said hydraulic material (A).Also provided are molded articles comprising a hydraulic material (A) and a polyvinyl alcohol (B), said polyvinyl alcohol (B) being contained in an amount of 0.1 to 20% by weight based on the weight of said hydraulic material (A), said molded article having a structure comprising said polyvinyl alcohol (B) having once dissolved and then solidified being dispersed therein in the form of islands. These molded articles have excellent flexural strength, flexibility and dimensional stability.

Abstract: Disclosed herein is a new process for producing polyvinyl ester having a high degree of polymerization having an intrinsic viscosity not less than 1.5 dl/g, preferably not less than 2.2 dl/g, and most preferably higher than 3.2 dl/g, said process comprising subjecting vinyl ester monomer to low-temperature emulsion polymerization under specific conditions.Disclosed also herein is a new process for producing polyvinyl alcohol having a high degree of polymerization having an intrinsic viscosity not less than 1.5 dl/g, preferably not less than 2.2 dl/g, and most preferably higher than 3.2 dl/g, said process comprising saponifying in the usual way the polyvinyl ester obtained by low-temperature emulsion polymerization under specific conditions.