Abrégé

Disclosed in the present invention is a method for synthesizing a homopolymer N-vinyl butyrolactam with low residual monomer and a low molecular weight, using an N-vinyl butyrolactam monomer and water at a weight ratio of 4:16—8:12 and then using 0.5%-5.0% weight of a composite polybasic initiator, 0.1%-0.5% weight of a catalyst, and 0.1%-10% weight of a chain transfer agent, on the basis of the N-vinyl butyrolactam monomer, in the presence of an insert gas, adding in batches the above raw materials, using an activator to adjust the reaction system to be at pH 7.0—8.0, the reaction being carried out at a polymerization temperature of 60°C—85°C; finally, adding a peroxide and maintaining the temperature for 2 hours and then using an acid to adjust the pH to acidity and maintaining this for l—3 h, so as to obtain a colourless and transparent aqueous solution of the homopolymer N-vinyl butyrolactam; after drying, a powdery homopolymer N-vinyl butyrolactam with a K value of 24-31, a low molecular weight and residual monomer below 10 ppm is obtained. The present invention is ingenious in design and simple in preparation. The prepared homopolymer N-vinyl butyrolactam with low residual monomer and low molecular weight has residual monomer below 10 ppm, a K value of 24-31, and is suitable for a large scale of popularization and application.

Classes IPC  ?

• C08F 126/10 - N-Vinylpyrrolidone
• C08F 26/10 - N-Vinylpyrrolidone
• C08F 4/30 - Composés inorganiques
• C08F 4/32 - Composés organiques
• C08F 4/04 - Composés azoïques

Abrégé

Disclosed is a method for synthesizing a homopolymer N-vinyl butyrolactam with a super-low molecular weight and super-low residual monomer, using an N-vinyl butyrolactam monomer and water at a weight ratio of 3:17~8:12, and then, on the basis of the N-vinyl butyrolactam monomer, using 0.5%~5.0% weight of an initiator 0.1%~5.0% weight of a catalyst, and 0.1%~5.0% weight of a molecular weight regulator, wherein the initiator comprises 25% weight of an initiator A, 67.5% weight of an initiator B, and 7.5% weight of an initiator C; adding in batches the above raw materials, in the presence of an inert gas, adjusting the reaction system to be at pH 7.0—8.0 using an activator, the reaction being carried out at a polymerization temperature of 60°C—85°C; finally, adding a peroxide and maintaining the temperature for 2 hours to obtain an aqueous solution of the homopolymer N-vinyl butyrolactam with a super-low molecular weight; after drying, a powdery homopolymer N-vinyl butyrolactam with a super-low molecular weight and super-low residual monomer being obtained, wherein the value of K is 12-17, the molecular weight is 2000—15000, and the residual monomer is below 10 ppm.

Classes IPC  ?

• C08F 126/06 - Homopolymères de composés contenant un ou plusieurs radicaux aliphatiques non saturés, chaque radical ne contenant qu'une seule liaison double carbone-carbone et l'un au moins étant terminé par une liaison simple ou double à l'azote ou par un hétérocycle contenant de l'azote par un hétérocycle contenant de l'azote
• C08F 4/38 - Mélanges de composés peroxydés
• C08F 6/10 - Élimination des matières volatiles, p. ex. monomères, solvants

Abrégé

Disclosed in the present invention is a method for preparing a homopolymer K90 aqueous solution of N-vinyl butyrolactam with low residual monomer, comprising: using 10-35% weight of an aqueous solution of N-vinyl butyrolactam monomer as a raw material in the presence of an inert gas, at a polymerization temperature of 55°C—90°C, carrying out a reaction under stirring for 2.5-4.5 h and during the reaction adding an initiator in batches, the initiator being a mixture of azodiisobutyronitrile and azobisisoheptonitrile and having a total amount of 0.01%-3% of the mass of N-vinyl butyrolactam monomer; after the K value of this system reaches 90-102, maintaining the temperature overnight at 95°C, adding a mixed acid in batches to adjust the pH to be at 2.0-7.0; during the removal of the residual monomer, the mixed acid being formed by mixing two acids selected from propane diacid, sulphuric acid and hydrochloric acid, so as to obtain 10-35% by weight of a colourless and transparent product residual monomer below 10 ppm and a stable K value of 90-102. The present invention is ingenious in design and simple in preparation. The prepared homopolymer K90 aqueous solution of N-vinyl butyrolactam has low residual monomer below 10 ppm, is colourless and stable in K value, and suitable for a large scale of popularization and application.

Classes IPC  ?

• C08F 126/10 - N-Vinylpyrrolidone
• C08F 26/10 - N-Vinylpyrrolidone
• C08F 6/10 - Élimination des matières volatiles, p. ex. monomères, solvants

Abrégé

Disclosed is a method for synthesizing an aqueous solution of homopolymer N-vinyl butyrolactam (K60) with low residual monomer and a middle-high molecular weight, using 20-50% weight of an aqueous solution of N-vinyl butyrolactam monomer as a raw material in the presence of an inert gas, at a polymerization temperature of 57°C—72°C, carrying out a reaction under stirring for 4-6 h, during which the temperature is increased in stages and an initiator is added in decreasing amounts, the initiator being azobisisoheptonitrile, the total amount of the initiator added being 0.01~2% of the mass of the N-vinyl butyrolactam monomer; after the K value of the system reaches 58~65, adding sulphuric acid to adjust the pH to be at 4.2-4.5, maintaining the temperature at 90-140°C and stirring for more than 4 hours to remove the residual monomer, so as to obtain 20-50% weight of a colourless and transparent aqueous solution of homopolymer N-vinyl butyrolactam (K60) with low residual monomer and a middle-high molecular weight, and having residual monomer below 10 ppm and the K value of 58-65.

Classes IPC  ?

• C08F 126/10 - N-Vinylpyrrolidone
• C08F 26/10 - N-Vinylpyrrolidone
• C08F 4/38 - Mélanges de composés peroxydés
• C08F 6/10 - Élimination des matières volatiles, p. ex. monomères, solvants

Abrégé

Provided is a method for formulating a high-stability non-ionic N-vinylbutyrolactam iodide solution, comprising dissolving high-stability non-ionic N-vinylbutyrolactam iodide in water, then adding citric acid, a iodine ion stabilizer, a non-ionic surfactant, and an emulsifying agent, and adjusting to pH 5 with a pH adjusting agent. Preferably, the iodine ion stabilizer is potassium iodate, the non-ionic surfactant is Tween 20, the emulsifying agent is polyethylene glycol 200, the pH adjusting agent is sodium hydroxide, and the high-stability non-ionic N-vinylbutyrolactam iodide is formed by complexing PVP-K30 and iodine in the presence of a grinding aid at a temperature of 60-90°C. Also provided is a high-stability non-ionic N-vinylbutyrolactam iodide solution formulated by the method. The high-stability non-ionic N-vinylbutyrolactam iodide solution of the present invention has a high stability, which is convenient for long-term storage and use.

Classes IPC  ?

• A01N 59/12 - Iode, p. ex. iodophoresSes composés
• A01P 3/00 - Fongicides
• A01P 1/00 - DésinfectantsComposés antimicrobiens ou leurs mélanges

Abrégé

Provided is a method for preparing non-ionic N-vinylbutyrolactam iodide, comprising stirring a non-ionic N-vinylbutyrolactam, iodine and a grinding aid for 1-12 hours at a temperature of 50-90°C at 50-80O r/min, wherein the non-ionic N-vinylbutyrolactam has a K value of 32±1, a main peak PD value of less than or equal to 1.6, and a moisture content of less than or equal to 2.5%. Preferably, the grinding aid is one or more selected from sodium chloride, sodium citrate, sodium carbonate and sodium phosphate, the amount of the grinding aid added is 0.02-2% of the total amount of non-ionic N-vinylbutyrolactam and iodide, and the non-ionic N-vinylbutyrolactam is PVP-K32. Also provided is non-ionic N-vinylbutyrolactam iodide prepared by the method.

Classes IPC  ?

• C08F 126/10 - N-Vinylpyrrolidone
• C07D 207/267 - Pyrrolidones-2 avec uniquement des atomes d'hydrogène ou des radicaux ne contenant que des atomes d'hydrogène et de carbone, liés directement aux autres atomes de carbone du cycle avec uniquement des atomes d'hydrogène ou des radicaux ne contenant que des atomes d'hydrogène et de carbone, liés directement à l'atome d'azote du cycle
• C08F 8/22 - Halogénation par réaction avec des halogènes libres