Abstract: There is described a method for applying an aqueous solution to the internal walls of a reactor, before the start of the polymerization reaction of vinyl chloride and/or vinyl acetate, which aqueous solution contains a salt of an anti-scaling agent which comprises a product of condensation of an aldehyde, a phenolic compound and an aromatic carboxylic acid hydroxylated at the aromatic nucleus, wherein the pH-value of this aqueous solution is changed, during the application, to a pH-value of less than 5 and, preferably, in the range between 2.5 and 4.5.

Abstract: There is described a method for applying an aqueous solution to the internal walls of a reactor, before the start of the polymerization reaction of vinyl chloride and/or vinyl acetate, which aqueous solution contains a salt of an anti-scaling agent which comprises a product of condensation of an aldehyde, a phenolic compound and an aromatic carboxylic acid hydroxylated at the aromatic nucleus, wherein the pH-value of this aqueous solution is changed, during the application, to a pH-value of less than 5 and, preferably, in the range between 2.5 and 4.5.

Abstract: The object of the invention is to provide a liquid anti-scaler for coating polymerizing reactors obtained by a condensation reaction of naphthol with an aldehydic cross-linking product, wherein the cross-linking product is the reaction product of hydrosulfite and formaldehyde. It contains hydrosulfite and/or radical bisulfites and/or bisulfite. The condensate is made in such a way that in the absence of oxygen, it is in the form of liquid of clear transparent color.

Abstract: This invention relates to a process for producing an anti-scaler product for coating polymerization reactors comprising condensing a naphthol with an aldehydic cross-linking agent, wherein the cross-linking agent is the reaction product of an aldehyde and a hydrosulphite.

Abstract: Process for the preparation of an aqueous emulsion of two or more polyvinyl alcohols (PVA) for the production of polyvinylchloride (PVC-S) in an aqueous suspension in which at least a first polyvinylacetate (PVAc) with molecular weight between 30 and 110K is utilized and, with technique of alcoholisis acid or basic, to carry out the trans-esterification of the PVAc until a saponification number between 598 and 135 is attained.