CN115433303A - Preparation method of soft water-based acrylic acid retanning agent for leather - Google Patents

Preparation method of soft water-based acrylic acid retanning agent for leather Download PDF

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CN115433303A
CN115433303A CN202211244723.7A CN202211244723A CN115433303A CN 115433303 A CN115433303 A CN 115433303A CN 202211244723 A CN202211244723 A CN 202211244723A CN 115433303 A CN115433303 A CN 115433303A
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acrylic acid
water
temperature
retanning agent
stirring tank
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CN202211244723.7A
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Chinese (zh)
Inventor
庄君新
苏晓峰
宁继鑫
高丙文
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Mingxin Menorca Jiangsu New Materials Co ltd
Mingxin Xuteng Jiangsu Innovation Research Institute Co ltd
Mingxin Xuteng New Material Co ltd
Jiangsu Mill Chemical Technology Co ltd
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Mingxin Menorca Jiangsu New Materials Co ltd
Mingxin Xuteng Jiangsu Innovation Research Institute Co ltd
Mingxin Xuteng New Material Co ltd
Jiangsu Mill Chemical Technology Co ltd
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Priority to CN202211244723.7A priority Critical patent/CN115433303A/en
Publication of CN115433303A publication Critical patent/CN115433303A/en
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    • CCHEMISTRY; METALLURGY
    • C08ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08FMACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
    • C08F220/00Copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and only one being terminated by only one carboxyl radical or a salt, anhydride ester, amide, imide or nitrile thereof
    • C08F220/02Monocarboxylic acids having less than ten carbon atoms; Derivatives thereof
    • C08F220/04Acids; Metal salts or ammonium salts thereof
    • C08F220/06Acrylic acid; Methacrylic acid; Metal salts or ammonium salts thereof
    • CCHEMISTRY; METALLURGY
    • C08ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08FMACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
    • C08F2/00Processes of polymerisation
    • C08F2/04Polymerisation in solution
    • C08F2/10Aqueous solvent
    • CCHEMISTRY; METALLURGY
    • C08ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08FMACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
    • C08F8/00Chemical modification by after-treatment
    • C08F8/44Preparation of metal salts or ammonium salts
    • CCHEMISTRY; METALLURGY
    • C14SKINS; HIDES; PELTS; LEATHER
    • C14CCHEMICAL TREATMENT OF HIDES, SKINS OR LEATHER, e.g. TANNING, IMPREGNATING, FINISHING; APPARATUS THEREFOR; COMPOSITIONS FOR TANNING
    • C14C3/00Tanning; Compositions for tanning
    • C14C3/02Chemical tanning
    • C14C3/08Chemical tanning by organic agents
    • C14C3/22Chemical tanning by organic agents using polymerisation products

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  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Organic Chemistry (AREA)
  • Health & Medical Sciences (AREA)
  • Medicinal Chemistry (AREA)
  • Polymers & Plastics (AREA)
  • General Chemical & Material Sciences (AREA)
  • Addition Polymer Or Copolymer, Post-Treatments, Or Chemical Modifications (AREA)

Abstract

The invention discloses a preparation method of a soft water-based acrylic acid retanning agent for leather, which comprises the following steps: an emulsification step: putting acrylic acid, butyl acrylate, itaconic acid and a part of water into a pre-emulsification kettle according to a predetermined proportion, and uniformly stirring; the initiator proportioning step: putting an initiator and water into a first metering stirring tank according to a preset proportion; the proportioning of the regulator comprises the following steps: adding the molecular weight regulator sodium bisulfite and water into a second metering stirring tank according to a preset proportion. Acrylic acid, butyl acrylate and itaconic acid are used as raw materials, are polymerized by a free radical aqueous solution, are dripped into a reaction kettle according to a certain proportion in the presence of an initiator for copolymerization reaction at a certain temperature, and are subjected to post-treatment reaction and neutralization reaction to prepare a soft water-based acrylic acid retanning agent, wherein the effective content of the product is 40 +/-2 percent, and the pH is =6-7; the retanning agent has the advantages of good permeability to leather, compact, plump and soft surface, reduction of the potential difference and the like.

Description

Preparation method of soft water-based acrylic acid retanning agent for leather
Technical Field
The invention relates to the technical field of production of water-based acrylic acid leather auxiliaries, and in particular relates to a preparation method of a soft water-based acrylic acid retanning agent for leather.
Background
The resin retanning agent is one of organic compound retanning agents, and the molecules of the resin retanning agent contain organic macromolecules or macromolecular compounds of functional groups capable of interacting with skin collagen. Generally, the relative molecular mass distribution of the resin retanning agent is wide, from hundreds to hundreds of thousands, the resin retanning agent has good water solubility, and the storage stability is generally more than one year. The resin retanning agent can reasonably fill the gaps of the leather collagen fiber bundles by utilizing the volume effect of the resin retanning agent, and is widely applied to the leather-making industry, while the acrylic retanning agent is one of the fastest-developing varieties in recent years.
Chinese patent No. CN201310131242.X discloses a soft acrylic resin leather retanning agent and a preparation method thereof. Firstly, carrying out esterification reaction on methyl ricinoleate and maleic anhydride to generate maleic acid monoester of methyl ricinoleate, and neutralizing with sodium hydroxide to obtain a methyl ricinoleate maleic acid monoester sodium salt monomer; then, carrying out free radical copolymerization on the methyl ricinoleate and maleic acid monoester sodium salt monomer and vinyl monomers in a water-based system to obtain the acrylic resin retanning agent with the side chain containing the long-chain lipophilic group with the methyl ricinoleate structure.
The above-mentioned and prior art retanning agents have poor penetration into the leather and poor softness, resulting in poor softness of the leather in use. Therefore, it is necessary to design a method for preparing a soft aqueous acrylic acid retanning agent for leather to solve the above problems.
Disclosure of Invention
The invention aims to provide a preparation method of a soft water-based acrylic acid retanning agent for leather, which aims to overcome the defects in the prior art.
In order to achieve the above purpose, the invention provides the following technical scheme:
a preparation method of a soft water-based acrylic acid retanning agent for leather comprises the following steps:
an emulsification step: putting acrylic acid, butyl acrylate, itaconic acid and a part of water into a pre-emulsification kettle according to a predetermined proportion, and uniformly stirring;
the initiator proportioning step: putting an initiator and water into a first metering stirring tank according to a preset proportion;
the proportioning step of the regulator: putting a molecular weight regulator sodium bisulfite and water into a second metering stirring tank according to a preset proportion;
and (3) matching a candidate initiator: respectively putting the candidate initiator and water into a third metering stirring tank according to a preset proportion;
the proportioning of the neutralizing agent comprises the following steps: adding a neutralizer and water into a fourth metering stirring tank according to a preset proportion;
a temperature-rising reaction step: adding a predetermined amount of water into a reaction kettle, heating to a predetermined temperature, dripping the pre-emulsified monomer of the pre-emulsification kettle and the two solutions in the first metering stirring tank and the second metering stirring tank into the reaction kettle at a predetermined speed according to a predetermined time, stirring after dripping, and keeping the temperature for a period of time;
and (3) obtaining a product: and after the heat preservation is finished, reducing the temperature of the reaction kettle to a preset temperature, adding the solution in the third metering stirring tank into the reaction kettle at a preset speed within a preset time, after the dropwise addition is finished, preserving the heat and stirring, then reducing the temperature of the reaction kettle to be below the preset temperature, adding the solution in the fourth stirring tank into the reaction kettle, maintaining the temperature to be below the preset temperature, and after the dropwise addition is finished, stirring and reacting for a period of time to obtain the product, namely the water-based acrylic acid retanning agent.
Preferably, in the temperature-rising reaction step, the temperature rising temperature is controlled to be 75-80 ℃, the time for dripping the pre-emulsified monomer and the pre-emulsified solution into the reaction kettle is 180-240min, and the heat preservation time after dripping the pre-emulsified monomer and the pre-emulsified solution is 30-40min.
Preferably, the mass ratio of the mixture of acrylic acid, butyl acrylate and itaconic acid, the initiator, the regulator sodium bisulfite and the neutralizer is as follows: 40-60:0.16-0.28:0.65-1.11:19-25.
Preferably, in the step of obtaining the product, the temperature is firstly reduced to a preset temperature of 65-70 ℃, the time for adding the solution in the third metering stirring tank into the reaction kettle is 40-60min, the heat preservation time after the solution is dropwise added is 65-70 ℃, and the stirring reaction time after the solution is dropwise added is 20-30min.
Preferably, in the step of obtaining the product, the cooling mode of the reaction kettle is cooling by cooling water, the temperature after cooling is controlled to be 40-60 ℃, the temperature when the neutralizing agent in the fourth metering stirring tank is dripped is 40-60 ℃, the dripping time is controlled to be 90-120min, and the stirring reaction time is 20-30min after dripping is finished. The water-based acrylic acid retanning agent can be obtained, the effective content of the product is 40 +/-2%, and the pH is =6-7.
Preferably, the effective content of the obtained product is 40 +/-2%, and the pH value of the obtained product is pH =6-7.
Preferably, the water is deionized water.
Preferably, the initiator is sodium persulfate or ammonium persulfate.
Preferably, the neutralizing agent is a 40% sodium hydroxide or potassium hydroxide solution.
Preferably, the deionized water is prepared by an RO reverse osmosis method.
In the technical scheme, the preparation method of the soft water-based acrylic acid retanning agent for leather provided by the invention has the beneficial effects that: acrylic acid, butyl acrylate and itaconic acid are used as raw materials, are polymerized by a free radical aqueous solution, are dripped into a reaction kettle according to a certain proportion in the presence of an initiator for copolymerization reaction at a certain temperature, and are subjected to post-treatment reaction and neutralization reaction to prepare a soft water-based acrylic acid retanning agent, the effective content of the product is 40 +/-2 percent, and the pH is =6-7; the retanning agent has the advantages of good permeability to leather, compact, plump and soft surface, reduction of the potential difference and the like.
Drawings
In order to more clearly illustrate the embodiments of the present application or technical solutions in the prior art, the drawings needed to be used in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments described in the present invention, and other drawings can be obtained by those skilled in the art according to the drawings.
FIG. 1 is a flow chart of the preparation method of the soft water-based acrylic acid retanning agent for leather according to the embodiment of the invention.
Detailed Description
In order to make those skilled in the art better understand the technical solution of the present invention, the present invention will be further described in detail with reference to fig. 1.
Example one
The preparation method of the soft water-based acrylic acid retanning agent for leather provided by the embodiment of the invention comprises the steps of putting 21g of acrylic acid, 2.2g of butyl acrylate, 1.0g of itaconic acid and 60g of water into a pre-emulsification kettle, and uniformly stirring for later use; 28g of sodium persulfate solution with the concentration of 4.5 percent is put into a first metering stirring tank for standby; putting 60g of sodium bisulfite solution with the concentration of 7.5 percent into a second metering stirring tank for standby; 15g of sodium persulfate solution with the concentration of the candidate initiator of 3 percent is put into a third metering stirring tank for standby; 210g of 40% sodium hydroxide solution is put into a fourth metering stirring tank for standby;
adding 260g of water into a reaction kettle, heating to 80 ℃, dropwise adding the pre-emulsified monomer in the pre-emulsifying kettle and the two solutions in the first metering stirring tank and the second metering stirring tank into the reaction kettle at a certain speed simultaneously, controlling the dropwise adding time to be 180min, ensuring that the simultaneous dropwise adding is finished, stirring and preserving the temperature for 35min after the dropwise adding is finished; and cooling to 70 ℃, adding the solution in the third metering stirring tank into the reaction kettle at a certain speed, controlling the dripping time to be 20min, cooling to below 60 ℃ after finishing dripping, adding the solution in the fourth stirring tank into the reaction kettle, keeping the temperature at 50 ℃, and stirring for reacting for 60min after finishing dripping to obtain the water-based acrylic acid retanning agent, wherein the effective content of the product is 41%, and the pH =6.4.
Example two
Putting 26g of acrylic acid, 1.9g of butyl acrylate, 1.4g of itaconic acid and 60g of water into a pre-emulsification kettle, and uniformly stirring for later use; putting 34g of sodium persulfate solution with the concentration of 4.5% into a first metering stirring tank for later use; 58g of sodium bisulfite solution with the concentration of 7.5 percent is put into a second metering stirring tank for standby; 20g of sodium persulfate solution with the concentration of the candidate initiator of 3 percent is put into a third metering stirring tank for standby; 205g of 50% sodium hydroxide solution are introduced into a fourth metering stirred tank for further use.
Adding 250g of water into a reaction kettle, heating to 80 ℃, simultaneously dripping the pre-emulsified monomer in the pre-emulsifying kettle and the two solutions in the first metering stirring tank and the second metering stirring tank into the reaction kettle at a certain speed, controlling the dripping time to be 190min, ensuring that the dripping is finished simultaneously, stirring and preserving the heat for 30min after the dripping is finished; and cooling to 70 ℃, adding the solution in the third metering stirring tank into the reaction kettle at a certain speed, controlling the dripping time to be 20min, cooling to below 60 ℃ after finishing dripping, adding the solution in the fourth stirring tank into the reaction kettle, keeping the temperature at 50 ℃, and stirring for reacting for 30min after finishing dripping to obtain the water-based acrylic acid retanning agent, wherein the effective content of the product is 40.56%, and the pH is =6.2.
EXAMPLE III
Putting 23g of acrylic acid, 2.5g of butyl acrylate, 2.0g of itaconic acid and 60g of water into a pre-emulsification kettle, and uniformly stirring for later use; 31g of sodium persulfate solution with the concentration of 4.5 percent is put into a first metering stirring tank for standby; 54g of sodium bisulfite solution with the concentration of 7.5 percent is put into a second metering stirring tank for standby; 25g of sodium persulfate solution with the concentration of the candidate initiator of 3 percent is put into a third metering stirring tank for standby; 215g of 50% sodium hydroxide solution are introduced into a fourth metering stirred tank for further use.
Adding 260g of water into a reaction kettle, heating to 76 ℃, dropwise adding the pre-emulsified monomer in the pre-emulsifying kettle and the two solutions in the first metering stirring tank and the second metering stirring tank into the reaction kettle at a certain speed, controlling the dropwise adding time to be 210min, ensuring that the simultaneous dropwise adding is finished, stirring and preserving the temperature for 20min after the dropwise adding is finished; and cooling to 70 ℃, adding the solution in the third metering stirring tank into the reaction kettle at a certain speed, controlling the dripping time to be 20min, cooling to below 60 ℃ after finishing dripping, adding the solution in the fourth stirring tank into the reaction kettle, keeping the temperature at 50 ℃, and stirring for reacting for 30min after finishing dripping to obtain the water-based acrylic acid retanning agent, wherein the effective content of the product is 41.67%, and the pH is =6.7.
Retanning application experiments
A piece of even-shaved wet blue leather is taken for an experiment, the wet blue leather is divided into four symmetrical pieces along a dorsal ridge line, the numbers 1#, 2#, 3#, 4#, and 1# are used as comparison test samples and are retanning agents RE of Pasteur company, and the other three groups are respectively used as three retanning agents in the embodiment of the invention. The process was carried out as shown in table 1:
TABLE 1
Figure BDA0003886018050000051
The permeability of the four retanning agents and the softness of the four pieces of crust leather after retanning and fatliquoring are evaluated in a sensory mode, the permeability of the retanning agent is 1-10 minutes, the softness of the crust leather is 1-10 minutes, and the results are shown in a table 2:
TABLE 2
Figure BDA0003886018050000052
Figure BDA0003886018050000061
As can be seen from table 2, retanning agent 1 did not differ much from RE, either in softness or permeability, or even softness was better than RE.
While certain exemplary embodiments of the present invention have been described above by way of illustration only, it will be apparent to those of ordinary skill in the art that the described embodiments may be modified in various different ways without departing from the spirit and scope of the present invention. Accordingly, the drawings and description are illustrative in nature and are not to be construed as limiting the scope of the invention.

Claims (10)

1. A preparation method of a soft water-based acrylic acid retanning agent for leather is characterized by comprising the following steps:
an emulsification step: putting acrylic acid, butyl acrylate, itaconic acid and a part of water into a pre-emulsification kettle according to a predetermined proportion, and uniformly stirring;
the initiator proportioning step: putting an initiator and water into a first metering stirring tank according to a preset proportion;
the proportioning step of the regulator: putting the molecular weight regulator sodium bisulfite and water into a second metering stirring tank according to a predetermined proportion;
the preparation method comprises the following steps: respectively putting the candidate initiator and water into a third metering stirring tank according to a preset proportion;
the proportioning of the neutralizing agent comprises the following steps: adding a neutralizer and water into a fourth metering stirring tank according to a preset proportion;
a temperature-rising reaction step: adding a predetermined amount of water into a reaction kettle, heating to a predetermined temperature, dripping the pre-emulsified monomer in the pre-emulsifying kettle and the two solutions in the first metering stirring tank and the second metering stirring tank into the reaction kettle at a predetermined speed at the same time according to a specified time, stirring after dripping, and keeping the temperature for a period of time;
and a product obtaining step: and after the heat preservation is finished, reducing the temperature of the reaction kettle to a preset temperature, adding the solution in the third metering stirring tank into the reaction kettle at a preset speed within a preset time, after the dropwise addition is finished, preserving the heat and stirring, then reducing the temperature of the reaction kettle to be below the preset temperature, adding the solution in the fourth stirring tank into the reaction kettle, maintaining the temperature to be below the preset temperature, and after the dropwise addition is finished, stirring and reacting for a period of time to obtain the product, namely the water-based acrylic acid retanning agent.
2. The method for preparing a soft type aqueous acrylic acid retanning agent for leather according to claim 1, wherein in the temperature-raising reaction step, the temperature is raised to 75-80 ℃, the time for dropping the pre-emulsified monomer and the pre-emulsified solution into the reaction kettle is 180-240min, and the holding time after dropping the pre-emulsified monomer and the pre-emulsified solution is 30-40min.
3. The method for preparing the soft water-based acrylic acid retanning agent for leather according to claim 1, wherein the mass ratio of the mixture of acrylic acid, butyl acrylate and itaconic acid to the mixture of the initiator, the regulator sodium bisulfite and the neutralizer is as follows: 40-60:0.16-0.28:0.65-1.11:19-25.
4. The method for preparing a soft type aqueous acrylic acid retanning agent for leather according to claim 1, wherein in the step of obtaining the product, the temperature is firstly reduced to a preset temperature of 65-70 ℃, the solution in the third metering stirring tank is added into the reaction kettle for 40-60min, the holding time after the solution is added is 65-70 ℃, and the stirring reaction time after the solution is added is 20-30min.
5. The method for preparing the soft type aqueous acrylic acid retanning agent for leather according to claim 1, wherein in the step of obtaining the product, the temperature of the reaction kettle is reduced by cooling water, the temperature after the temperature reduction is controlled to be 40-60 ℃, the temperature when the neutralizing agent in the fourth metering stirring tank is added is controlled to be 40-60 ℃, the adding time is controlled to be 90-120min, and the stirring reaction time is 20-30min after the adding is finished. The water-based acrylic acid retanning agent can be obtained, the effective content of the product is 40 +/-2%, and the pH =6-7.
6. The method for preparing the soft type aqueous acrylic acid retanning agent for leather according to claim 1, wherein the effective content of the obtained product is 40 ± 2%, and the pH value of the obtained product is pH =6-7.
7. The method for preparing the soft type aqueous acrylic acid retanning agent for leather according to claim 1, wherein the water is deionized water.
8. The method for preparing the soft type aqueous acrylic acid retanning agent for leather according to claim 1, wherein the initiator is sodium persulfate or ammonium persulfate.
9. The method for preparing the soft type aqueous acrylic acid retanning agent for leather according to claim 1, wherein the neutralizer is a 40% sodium hydroxide or potassium hydroxide solution.
10. The method for preparing the soft type aqueous acrylic acid retanning agent for leather according to claim 7, wherein the deionized water is prepared by an RO reverse osmosis method.
CN202211244723.7A 2022-10-12 2022-10-12 Preparation method of soft water-based acrylic acid retanning agent for leather Withdrawn CN115433303A (en)

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Application publication date: 20221206