CN108249792B - Preparation method of protein polypeptide gypsum retarder - Google Patents
Preparation method of protein polypeptide gypsum retarder Download PDFInfo
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- CN108249792B CN108249792B CN201810069496.6A CN201810069496A CN108249792B CN 108249792 B CN108249792 B CN 108249792B CN 201810069496 A CN201810069496 A CN 201810069496A CN 108249792 B CN108249792 B CN 108249792B
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- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B11/00—Calcium sulfate cements
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B24/00—Use of organic materials as active ingredients for mortars, concrete or artificial stone, e.g. plasticisers
- C04B24/24—Macromolecular compounds
- C04B24/28—Macromolecular compounds obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds
- C04B24/30—Condensation polymers of aldehydes or ketones
- C04B24/305—Melamine-formaldehyde condensation polymers
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
- C08G12/00—Condensation polymers of aldehydes or ketones with only compounds containing hydrogen attached to nitrogen
- C08G12/02—Condensation polymers of aldehydes or ketones with only compounds containing hydrogen attached to nitrogen of aldehydes
- C08G12/26—Condensation polymers of aldehydes or ketones with only compounds containing hydrogen attached to nitrogen of aldehydes with heterocyclic compounds
- C08G12/30—Condensation polymers of aldehydes or ketones with only compounds containing hydrogen attached to nitrogen of aldehydes with heterocyclic compounds with substituted triazines
- C08G12/32—Melamines
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2103/00—Function or property of ingredients for mortars, concrete or artificial stone
- C04B2103/20—Retarders
- C04B2103/22—Set retarders
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- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Ceramic Engineering (AREA)
- Organic Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Materials Engineering (AREA)
- Structural Engineering (AREA)
- Health & Medical Sciences (AREA)
- Medicinal Chemistry (AREA)
- Polymers & Plastics (AREA)
- Phenolic Resins Or Amino Resins (AREA)
Abstract
The invention discloses a preparation method of a protein polypeptide gypsum retarder, which is based on the characteristics of hydrophilicity and calcium affinity of protein polypeptide and carries out chemical modification on protein. Polypeptide and nitrogenous poly-hydroxymethyl are synthesized into a dendritic compound after collagen degradation. The retarder has good dispersion and water retention functions, does not crystallize and aggregate in gypsum, does not influence the formation of gypsum crystals, has the retardation time of more than 300min, and keeps the gypsum strength better. After the samples are detected, the samples all reach the national building gypsum grade 3 standard (GB/T9776-2008).
Description
Technical Field
The invention relates to the technical field of gypsum retarders, in particular to a gypsum retarder prepared from resin obtained by condensing protein polypeptide and melamine.
Background
The retarder is one of necessary components of various gypsum-based materials such as plastering gypsum, gypsum-based putty, model gypsum and the like. There are three main types of retarders commonly used at present: inorganic phosphates, organic polycarboxylates, and proteins. The organic acid retarder mainly comprises citric acid, tartaric acid, acrylic acid and the like, the inorganic phosphate retarder mainly comprises sodium hexametaphosphate, sodium polyphosphate and the like, and the protein retarder comprises bone glue, collagen polypeptide and the like. The gypsum retarder inevitably exerts a negative influence on the strength of the gypsum-hardened body while retarding setting. Generally, the longer the retardation time, the greater the magnitude of the decrease in intensity. For example, the strength loss of the common protein retarder is more than 30 percent when the initial setting time of the gypsum is prolonged to 6 hours; the organic acid retarder is used, so that the strength loss of the gypsum exceeds 50% when the initial setting time of the gypsum is prolonged to 4 h; . Therefore, how to reduce the influence of the retarder on the strength of gypsum has been an important issue for retarder research.
The protein retarder has little damage to the strength of the gypsum. The development of novel protein retarders has also been of interest. The retarding effect of the protein retarder is derived from the water retention effect of the protein colloid, and the protein retarder has small influence on the final formation and transformation of crystals of the dihydrate gypsum, thereby having small strength loss. Based on the molecular weight and strong intermolecular binding, the protein contracts to form intramolecular or intermolecular binding in environments with different interfacial electric constants, thereby reducing the binding sites of water. The linear protein polypeptides may be dispersed within the gypsum body, but for retardation, the intervention of a large amount of protein polypeptides will reduce the crystallization capacity or alter the crystal morphology of the gypsum. The crystal volume is ensured to be stable in order to reduce the contact points between the gypsum crystals. Degradation of larger molecules of protein under the action of alkali, heat and oxidants (including air) has two effects, 1) molecular weight reduction after hydrolysis; 2) the amino groups of the polypeptide side chains are condensed, resulting in a reduction in the number of amino groups. The protein polypeptide, the organic nitrogen-containing substance and the formaldehyde are subjected to condensation reaction to prepare a dendritic type, under a certain pH value, anions among the polypeptides are mutually repelled and spread, the self aggregation of the retarder is prevented, and meanwhile, a water molecule storage space is obtained. The water retention point of unit volume is reduced under the same consumption of retarder, the water retention amount of each point is increased, and the water transfer in unit volume is ensured. The retarding efficiency is improved, and the method is a feasible technical route.
Disclosure of Invention
Based on the technical problems in the background art, the invention provides a gypsum retarder prepared from a protein polypeptide condensation compound resin.
The technical scheme of the invention is as follows:
a preparation method of a protein polypeptide gypsum retarder comprises the following steps:
1) adding water, organic nitrogen-containing substances and formaldehyde into a reactor, uniformly stirring, adjusting the pH to 9-11 by using a 30% sodium hydroxide solution, then heating to 80-90 ℃, reacting for 1-2 h, cooling to 45-55 ℃, and obtaining a N-methylol condensation compound;
2) adding 45% of protein solution and 30% of sodium hydroxide solution into a reactor, uniformly stirring, keeping the pH value to 11-12, heating to 70-80 ℃, reacting for 0.5-1.5 h, adjusting the pH value to 9.0-9.5 by using 10% of sulfuric acid solution, cooling to 45-55 ℃, and obtaining the molecular weight of a degraded polypeptide product of 1500-3000;
3) adding the degradation product obtained in the step 2) into the nitrogen hydroxymethyl condensation compound obtained in the step 1), uniformly stirring, adjusting the pH value to 8.0-9.0 by using a 10% sulfuric acid solution, then heating to 60-70 ℃, reacting for 1-2 h, heating to 70-75 ℃, reacting for 1-2 h, heating to 80-85 ℃, reacting for 1-2 h, cooling to 45-55 ℃, adding a stabilizer and water, stirring for 30-40 min at 45-55 ℃, and obtaining a yellow viscous liquid of 300-400 mPa & s.
Preferably, in the step 1), the organic nitrogen-containing substance may be melamine, dicyandiamide, triaminoguanidine hydrochloride, triaminobenzene, and the molar ratio of the organic nitrogen-containing substance to formaldehyde is 1: 3-3.5. .
Preferably, the protein in the protein solution is any one of leather waste animal hide glue, commercially available industrial gelatin and bone glue.
Preferably, the stabilizer in the step 3) can be any one of a diffusant NNOL, sodium naphthalenesulfonate and benzene sulfonic acid formal, wherein the molar ratio of the stabilizer to the organic nitrogen-containing compound is (0.3-0.5): 1, and water is added until the solid content of the product is 25% -35%.
Preferably, in the step 3), the molar ratio of the degradation products to the organic nitrogen-containing substances is (2-4): 1 according to 2000 molecular weight.
The reaction scheme of the invention is as follows:
in the above illustration, R (NH)2-3 may be any one of melamine, dicyandiamide, triaminoguanidine hydrochloride, triaminobenzene.
The invention has the advantages that: the application result of the material of the invention has the following advantages:
1) from two indexes of the coagulation time and the strength loss, the invention has the advantages of long coagulation time and small strength loss, and the three embodiments all reach the national third-level standard.
2) When the gypsum-gypsum composite material is used, no inorganic salt is added, and the gypsum is free from defects caused by crystallization due to poor local dispersion of the inorganic salt caused by uneven stirring in production implementation.
3) The initial setting time and the final setting time of the material are close to each other, and the sufficient fluidity in the processing process is met. The setting time of the gypsum can also be adjusted according to the mixing amount of the blank and the retarder.
4) The protein polypeptide material utilized by the invention has wide sources, such as leather-making waste animal skins and degradation products.
The invention carries out chemical modification on the protein based on the hydrophilic and calcium-philic characteristics of the protein. Degraded polypeptide and melamine formaldehyde are utilized to synthesize a dendritic compound. Because the retarder has a good water retention function, the retarder is not crystallized in gypsum, the formation of gypsum crystals is not influenced, and the original strength of the gypsum is kept to be good finally. The examples all reach the national building gypsum grade 3 standard (GB/T9776-2008).
The material of the invention can be used alone as a retarder core material, and can also be used as a component to be compounded with other materials, however, the use of the material in a retarder formula should be regarded as the protection scope of the invention.
Detailed Description
Retarder Synthesis example 1
1) Adding 1 mol of melamine and 3.2 mol of formaldehyde into a reactor, adding water with the mass of 3 times that of the melamine, uniformly stirring, adjusting the pH to 9-11 by using a 30% sodium hydroxide solution, then heating to 80-90 ℃, reacting for 1-2 h, and cooling to 45-55 ℃ to obtain a melamine N-methylol condensation compound;
2) adding 45% of glue solution and 30% of sodium hydroxide solution into a reactor, uniformly stirring, keeping the pH value to 11-12, heating to 70-80 ℃, reacting for 0.5-1.5 h, adjusting the pH value to 9.0-9.5 by using 10% of sulfuric acid solution, cooling to 45-55 ℃, and obtaining the molecular weight of the degraded polypeptide product of 1500-3000;
3) adding the degradation product obtained in the step 2) into the melamine-N-methylol condensation product obtained in the step 1) according to a molecular weight of 2000, wherein the molar ratio of the degradation product to melamine is 3:1, uniformly stirring, adjusting the pH to 8.0-9.0 by using a 10% sulfuric acid solution, heating to 60-70 ℃, reacting for 1-2 h, heating to 70-75 ℃, reacting for 1-2 h, heating to 80-85 ℃, reacting for 1-2 h, cooling to 45-55 ℃, adding a stabilizer (the molar ratio of the stabilizer to melamine is 0.4) and a proper amount of water at 45-55 ℃, stirring for 30-40 min, and obtaining a yellow viscous liquid with a solid content of 25-35% and a solid content of 350-400 mPas.
Retarder Synthesis example 2
1) Adding 1 mole of triaminobenzene and 3.5 moles of formaldehyde into a reactor, adding water with the mass of 3 times that of triaminobenzene, uniformly stirring, adjusting the pH to 9-11 by using a 30% sodium hydroxide solution, then heating to 80-90 ℃, reacting for 1-2 hours, cooling to 45-55 ℃, and obtaining a triaminobenzene nitrogen hydroxymethyl condensation compound;
2) adding 45% of gelatin solution and 30% of sodium hydroxide solution into a reactor, uniformly stirring, keeping the pH value to 11-12, heating to 70-80 ℃, reacting for 0.5-1.5 h, adjusting the pH value to 9.0-9.5 by using 10% of sulfuric acid solution, cooling to 45-55 ℃, and obtaining the molecular weight of the degraded polypeptide product of 1500-3000;
3) adding the degradation product obtained in the step 2) into the triaminobenzene nitrogen hydroxymethyl condensation compound obtained in the step 1) according to a molecular weight of 2000, wherein the molar ratio of the degradation product to triaminobenzene is 3:1, uniformly stirring, adjusting the pH to 8.0-9.0 by using a 10% sulfuric acid solution, heating to 60-70 ℃, reacting for 1-2 h, heating to 70-75 ℃, reacting for 1-2 h, heating to 80-85 ℃, reacting for 1-2 h, cooling to 45-55 ℃, adding a stabilizer (the molar ratio of triaminobenzene is 0.3) and a proper amount of water, stirring for 30-40 min at 45-55 ℃, and obtaining a yellow viscous liquid with a solid content of 25-35% and a concentration of 300-350 mPas.
Retarder Synthesis example 3
1) Adding 1 mole of triaminoguanidine hydrochloride and 3.5 moles of formaldehyde into a reactor, adding water with the mass of 3 times that of the triaminoguanidine hydrochloride, uniformly stirring, adjusting the pH to 9-11 by using a 30% sodium hydroxide solution, then heating to 80-90 ℃, reacting for 1-2 hours, cooling to 45-55 ℃, and obtaining a triaminoguanidine hydrochloride N-methylol condensate;
2) adding 45% of gelatin solution and 30% of sodium hydroxide solution into a reactor, uniformly stirring, keeping the pH value to 11-12, heating to 70-80 ℃, reacting for 0.5-1.5 h, adjusting the pH value to 9.0-9.5 by using 10% of sulfuric acid solution, cooling to 45-55 ℃, and obtaining the molecular weight of the degraded polypeptide product of 1500-3000;
3) adding the degradation product obtained in the step 2) into the triaminoguanidine hydrochloride nitrogen-hydroxymethyl condensation product obtained in the step 1) according to a molecular weight of 2000, wherein the molar ratio of the degradation product to triaminoguanidine hydrochloride is 3:1, uniformly stirring, adjusting the pH to 8.0-9.0 by using a 10% sulfuric acid solution, heating to 60-70 ℃, reacting for 1-2 h, heating to 70-75 ℃, reacting for 1-2 h, heating to 80-85 ℃, reacting for 1-2 h, cooling to 45-55 ℃, adding a stabilizer (the molar ratio of the stabilizer to triaminoguanidine hydrochloride is 0.4) and a proper amount of water at 45-55 ℃, stirring for 30-40 min, and obtaining a yellow viscous liquid with the solid content of 25-35% and 350-350 mPas.
Retarder application examples
The addition amount of the retarder is 0.2 percent (mass fraction) of the mass of the gypsum, the standard thickening water requirement of the gypsum is 0.50, and the setting time and the strength performance test are carried out according to the building gypsum GB/T9776-.
TABLE 1 physical and mechanical properties of building gypsum
The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art should be considered to be within the technical scope of the present invention, and the technical solutions and the inventive concepts thereof according to the present invention should be equivalent or changed within the scope of the present invention.
Claims (3)
1. A preparation method of a protein polypeptide gypsum retarder is characterized by comprising the following steps:
1) adding water, organic nitrogen-containing substances and formaldehyde into a reactor, uniformly stirring, adjusting the pH to 9-11 by using a 30% sodium hydroxide solution, then heating to 80-90 ℃, reacting for 1-2 h, and cooling to 45-55 ℃ to obtain a N-methylol condensation compound;
2) adding 45% of protein solution and 30% of sodium hydroxide solution into a reactor, uniformly stirring, keeping the pH value to 11-12, heating to 70-80 ℃, reacting for 0.5-1.5 h, adjusting the pH value to 9.0-9.5 by using 10% of sulfuric acid solution, cooling to 45-55 ℃, and obtaining the molecular weight of a degraded polypeptide product of 1500-3000;
3) adding the degradation product obtained in the step 2) into the nitrogen hydroxymethyl condensation compound obtained in the step 1), uniformly stirring, adjusting the pH value to 8.0-9.0 by using a 10% sulfuric acid solution, then heating to 60-70 ℃, reacting for 1-2 h, heating to 70-75 ℃, reacting for 1-2 h, heating to 80-85 ℃, reacting for 1-2 h, cooling to 45-55 ℃, adding a stabilizer and water, stirring for 30-40 min at 45-55 ℃, and obtaining a yellow viscous liquid of 300-400 mPa & s;
the protein in the protein liquid is any one of leather waste animal skin glue, commercially available industrial gelatin and bone glue;
in the step 1), the organic nitrogen-containing substance is melamine, dicyandiamide, triaminoguanidine hydrochloride and triaminobenzene, and the molar ratio of the organic nitrogen-containing substance to formaldehyde is 1: 3-3.5;
in the step 3), the molar ratio of the degradation product to the organic nitrogen-containing compound is (3-4): 1 according to a molecular weight of 2000.
2. The preparation method of the protein polypeptide gypsum retarder as claimed in claim 1, wherein the stabilizer in the step 3) is any one of sodium naphthalenesulfonate and benzene sulfonic acid formal, wherein the molar ratio of the stabilizer to the organic nitrogen-containing substance is (0.3-0.5): 1, and water is added until the solid content of the product is 25% -35%.
3. The protein polypeptide gypsum retarder prepared by the preparation method of the protein polypeptide gypsum retarder as claimed in claim 1 or 2.
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| CN112028526A (en) * | 2020-09-14 | 2020-12-04 | 泰山石膏有限公司 | Gypsum retarder and preparation method and application thereof |
| CN115678034B (en) * | 2022-10-14 | 2024-04-19 | 海南太和科技有限公司 | Modified plant hydrolyzed protein retarder and preparation method and application thereof |
| CN117567066B (en) * | 2024-01-16 | 2024-03-22 | 申辉(河北)精化有限责任公司 | Modified protein polypeptide-based gypsum retarder and preparation method thereof |
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| JP2001261395A (en) * | 2000-03-16 | 2001-09-26 | Ajinomoto Co Inc | Setting retarder for gypsum |
| CN104086115A (en) * | 2014-07-14 | 2014-10-08 | 广东龙湖科技股份有限公司 | Gypsum retarder capable of improving strength and binding strength of gypsum base material |
| CN105777036A (en) * | 2016-03-16 | 2016-07-20 | 武汉理工大学 | Phosphorus-based salt mine goaf filler prepared from ardealite solidification salt waste |
| CN107098667A (en) * | 2017-06-28 | 2017-08-29 | 武汉菡美洛建筑材料有限公司 | Gypsum base light energy conservation plate and preparation method thereof |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN104072786B (en) * | 2014-06-17 | 2019-04-23 | 徐州鸿丰高分子材料有限公司 | A kind of resin and preparation method thereof of polypeptide and amino substance condensation |
| CN104773971B (en) * | 2015-04-08 | 2017-01-04 | 苏州市兴邦化学建材有限公司 | A kind of calcium sulphate retarder and preparation method thereof |
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Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2001261395A (en) * | 2000-03-16 | 2001-09-26 | Ajinomoto Co Inc | Setting retarder for gypsum |
| CN104086115A (en) * | 2014-07-14 | 2014-10-08 | 广东龙湖科技股份有限公司 | Gypsum retarder capable of improving strength and binding strength of gypsum base material |
| CN105777036A (en) * | 2016-03-16 | 2016-07-20 | 武汉理工大学 | Phosphorus-based salt mine goaf filler prepared from ardealite solidification salt waste |
| CN107098667A (en) * | 2017-06-28 | 2017-08-29 | 武汉菡美洛建筑材料有限公司 | Gypsum base light energy conservation plate and preparation method thereof |
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