Abstract: A polymer scale preventive agent for use in polymerization of a monomer having an ethylenically unsaturated double bond, comprising an alkaline solution containing (A) a condensation product of (A-1) a hydroxynaphthalene compound and (A-2) an aldehyde compound, and (B) an inorganic colloid. This agent is used for forming a coating on the inner wall, etc. of a polymerization vessel. Such a vessel is effective in preventing polymer scale deposition, not only in the liquid-phase region but also in the vicinity of the interface between the gas and liquid phases in the vessel, and useful in producing a polymer that shows very few fish eyes and good whiteness when formed into sheets or the like.

Abstract: A polymer scale preventive agent for use in polymerization of a monomer having an ethylenically unsaturated double bond, comprising an alkaline solution containing: (A) a condensation product of (A-1) a condensate of acetone with a hydroxybenzene compound having at least two hydroxyl groups, and (A-2) an aldehyde compound; (B) an inorganic colloid; and (C) a water-soluble polymeric compound. This agent is used for forming a coating on the inner wall, etc. of a polymerization vessel. Such a vessel is effective in preventing polymer scale deposition, not only on the areas in the liquid-phase region but also on the areas around the interface between the gas and liquid phases in the vessel, and useful in producing a polymer that shows very few fish eyes and good whiteness when formed into sheets or the like.

Abstract: A polymer scale deposition preventive agent for use in polymerization of a monomer having an ethylenically unsaturated double bond, comprising an alkaline solution containing a condensation product of (A) an anthraquinone compound having at least two amino groups and (B) at least one compound selected from the group consisting of benzoquinone compounds and naphthoquinone compounds. When the monomer is polymerized in a polymerization vessel having a coating formed by applying the aforementioned preventive agent to inner wall surfaces followed by drying, polymer scale can be effectively prevented from being deposited not only on the areas located in the liquid-phase region but also on the areas around the interface between the gas and liquid phases in the polymerization vessel. When an obtained polymer is formed into a sheet or the like, it is possible to obtain a formed product having few fish eyes and low initial coloration.

Abstract: The polymer scale preventive agent comprises an alkaline solution containing (A) an condensation product of (A-1) a hydroxybiphenyl compound with (A-2) an aldehyde compound, (B) a reaction stopper, and (C) an inorganic colloid and is used for polymerization of a monomer having an ethylenically unsaturated double bond. The process of producing the polymer comprises polymerizing the monomer in a polymerization vessel having a coating film on its inner wall surfaces, whereby polymer scale is prevented from being deposited, wherein said coating film is formed by applying, on said inner wall surfaces, said alkaline solution, followed by drying. According to the invention, deposition of polymer scale can be effectively prevented not only on the areas in the liquid phase but also at and in the vicinity of the interface between the gas and liquid phases in a polymerization vessel.

Abstract: A process for producing a polymer of a monomer having an ethylenically unsaturated double bond is described, wherein the monomer is polymerized in a polymerization vessel having a coating on its inner wall surfaces of a specific three-component polymer scale preventive agent, these three components are a naphthoquinone dimer, a water soluble polymer, and an inorganic colloid, whereby polymer scale is prevented from being deposited on the inner wall surfaces of the polymerization vessel.

Abstract: A polymer scale preventive process for use in polymerization of a monomer having an ethylenically unsaturated double bond, comprising (A) a water-soluble basic polysaccharide and (B) a phenothiazine. The process is used for forming a coating on the inner wall, etc. of a polymerization vessel, and highly safe for operators. Deposition of polymer scale can be effectively prevented, and polymeric product with high whiteness or a low initial coloration is obtained.

Abstract: A polymer scale preventive process for use in polymerization of a monomer having an ethylenically unsaturated double bond, comprising an alkaline solution containing a condensation product of (A) an aromatic amine compound having at least two amino groups and (B) an aromatic tetracarboxylic acid anhydride. This process is used for forming a coating on the inner wall, etc. of a polymerization vessel. Such a vessel is effective in preventing polymer scale deposition and useful in producing a polymer that shows very few fish eyes and good whiteness when formed into sheets or the like.

Abstract: A polymer scale preventive process for use in polymerization of a monomer having an ethylenically unsaturated double bond, comprising an alkaline solution containing (A) a condensation product of (A-1) an aromatic compound having at least two amino groups with (A-2) an aromatic tetracarboxylic acid anhydride, and (B) at least one member selected from the group consisting of (B-1) a water-soluble polymeric compound and (B-2) an inorganic colloid. The scale preventive process is low in virulence or the like, and high in safety. The process is used for forming a coating on inner wall surfaces of a polymerization vessel. Where such a polymerization vessel is used to carry out the polymerization, polymer scale deposition can be effectively prevented, not only on areas in the liquid-phase region but on areas around the gas-liquid interface in the vessel, and the resulting polymeric product shows few fish eyes and good whiteness when formed into sheets or the like.

Abstract: A polymer scale preventive process for use in polymerization of a monomer having an ethylenically unsaturated double bond, comprising an alkaline solution containing a condensation product of (A) an aromatic amine compound and (B) a quinone compound. This process is used for forming a coating on the inner wall, etc. of a polymerization vessel. Such a vessel is effective in preventing polymer scale deposition and useful in producing a polymer that shows very few fish eyes and good whiteness when formed into sheets or the like.

Abstract: A monomer having an ethylenic double bond is polymerized in a polymerization vessel provided on its inner wall surfaces with a coating of a polymer scale preventive agent which comprises a condensation product of an aromatic amine compound with an aromatic hydroxyl compound condensate. This process makes it possible to prevent effectively the deposition of polymer scale and to produce a polymer which shows few fish eyes and good whiteness when formed into sheets or the like.

Abstract: A polymer scale deposition preventive agent for use in polymerization of a monomer having an ethylenically unsaturated double bond, comprising an alkaline solution containing a condensation product of (A) a diphenyl compound having at least two amino groups and (B) a quinone compound. When the aforementioned monomer is polymerized in a polymerization vessel having a coating formed by applying the aforementioned preventive agent to inner wall surfaces followed by drying, polymer scale can be effectively prevented from being deposited not only on the areas located in the liquid-phase region but also on the areas around the interface between the gas and liquid phases in the polymerization vessel. When an obtained polymer is formed into a sheet or the like, it is possible to obtain a formed product having few fish eyes and good initial coloration.

Abstract: A process to prevent scale adhesion to reactor surfaces using an alkaline solution of the condensation product of an aromatic diamino compound and a quinone. The aromatic amino compound has the general formula (1): ##STR1## wherein R.sup.1 is at least one group selected from the group consisting of --OH, --COOH and --SO.sub.3 H, R.sup.2 is a hydrogen atom or a substituent group, X is a single bond or a divalent group of the formula --CH.dbd.CH--, and m and n are each an integer from 0 to 4, provided m and n are not simultaneously zero, when a plurality of R.sup.1 groups are present they may be identical or different, and when a plurality of R.sup.2 groups are present they may be identical or different, with (A-2) a quinone compound, and a process for producing a polymer using the agent are disclosed.

Abstract: A polymer scale preventive agent for coating internal reactor surfaces. The coating is a condensation product of an aromatic amine and a quinone in an alkaline solvent, used in conjunction with colloidal silica and/or alkali metal silicates.

Abstract: A process to prevent the adhesion of polymer scale during the polymerization of vinyl monomers which involves coating the internal reactor surfaces with the condensation product of a diamino heterocyclic and an amine compound. The coating is applied as an alkaline solution followed by drying. The coating is effective in preventing scale adhesion on the portions of the reactor exposed to the liquid phase reaction medium as well as the gas-liquid interface. The polymer resulting from use of the coating exhibits few fish eyes and little discoloration.

Abstract: A process to inhibit scale adhesion to the interior of a polymerization vessel using a two part coating composition. The coating is a hydroxyanthraquinone compound used in conjunction with a water soluble salt of chitosan, applied as a solution and dried on the vessel interior. Advantages of the coating are its effective scale prevention, unaltered color of the polymer product and low toxicity.

Abstract: A polymer scale preventive agent for use in polymerization of a monomer having an ethylenically unsaturated double bond, comprising (A) a pyrogallol-acetone resin, and (B) a water-soluble polymeric compound. When a coating comprising the polymer scale preventive agent is formed on inner wall surfaces of a polymerization vessel and the polymerization is carried out by use of the vessel, deposition of polymer scale can be effectively prevented not only in the areas in the liquid phase inside the vessel but also in the vicinity of the interface between the gas phase and the liquid phase in the vessel. The polymeric product thus obtained can then be processed into sheets or other formed products which have few fish eyes and low initial coloration.

Abstract: A polymer scale preventive liquid for use in polymerization of a monomer having an ethylenic double bond, comprising (A) a protein and (B) an anionic polysaccharide, and having a pH 7 or less; and a method of preventing polymer scale deposition in a polymerization vessel, which comprises carrying out the polymerization of said monomer in a polymerization vessel having a coating on its inner wall surfaces by applying said liquid and then drying. Deposition of polymer scale can be effectively prevented; in addition, polymers with a high whiteness can be prepared. Moreover, this polymer scale preventive liquid has no poisonousness and is highly safe.

Abstract: A polymer scale preventive agent for use in polymerization of a monomer having an ethylenically unsaturated double bond, comprising an alkaline solution containing a condensation product of (A) an aromatic dibasic acid dihydrazide compound, and (B) an aromatic tetracarboxylic acid anhydride. This agent is used for forming a coating on the inner wall, etc. of a polymerization vessel. Such a vessel is effective in preventing polymer scale deposition and useful in producing a polymer that shows very few fish eyes and good whiteness when formed into sheets or the like.

Abstract: A process and coated vessel for use in the prevention of scale adhesion during the polymerization of a monomer having an ethylenic double bond, the two part coating comprising an N-substituted leucophenothiazine dye having the general formula (I): wherein Z is a carbonyl group or a sulfonyl group, R.sup.1, R.sup.2 and R.sup.3 are a hydrogen atom, alkyl group, an amino group, etc., used in conjunction with a vinyl pyrrolidone polymer. The two part coating is used on the inner wall, etc. of a polymerization vessel. Deposition of polymer scale can be effectively prevented, and polymeric product with high whiteness is obtained.

Abstract: A polymer scale preventive agent for use in polymerization of a monomer having an ethylenically unsaturated double bond, comprising a condensation product of:(A) an aromatic amine compound, and(B) an aromatic hydroxyl compound condensate.This agent is used for forming a coating on the inner wall, etc. of a polymerization vessel. Such a vessel is effective in preventing polymer scale deposition and useful in producing a polymer that shows very few fish eyes and good whiteness when formed into sheets or the like.