阅读说明：本技术 一种用于提高皮革制品柔软性的加脂剂制备方法 (Preparation method of fatting agent for improving softness of leather products ) 是由 杨翠娥 于 2019-12-10 设计创作，主要内容包括：本发明涉及新材料加工技术领域,公开了一种用于提高皮革制品柔软性的加脂剂制备方法,以蓖麻油为原料,利用有机改性制备加脂剂,对皮革进行处理,处理后的皮革柔软不僵硬,加脂成革效果突出,革面柔软丰满,无油斑残留,同时还具有提高皮革鞣性、耐洗性、耐光性等功能,不仅能够提高皮革制品的柔软性、耐磨性,还具有防水防霉效果；赋予皮革优异的质地手感,该加脂剂化学稳定性高,制备成本低,具有极好的皮质适用性,对皮质无损害,同时能够延长皮革制品的使用寿命,实现了经济效益和环保效益；本发明能够显著提皮革制品的综合性能,解决现有皮革制造行业存在的问题,使得皮革制品能够长久保持柔软,手感滋润。(The invention relates to the technical field of new material processing, and discloses a preparation method of a fatting agent for improving the softness of a leather product, which takes castor oil as a raw material, prepares the fatting agent by utilizing organic modification, treats leather, ensures that the treated leather is soft and not stiff, has outstanding fatting and leather-forming effects, is soft and plump in leather surface, does not have oil spot residue, simultaneously has the functions of improving the tanning property, the washing resistance, the light resistance and the like of the leather, can improve the softness and the wear resistance of the leather product, and also has the waterproof and mildewproof effects; the leather is endowed with excellent texture hand feeling, the fatting agent has high chemical stability, low preparation cost, excellent leather applicability and no damage to leather, and simultaneously, the service life of a leather product can be prolonged, and economic benefits and environmental protection benefits are realized; the invention can obviously improve the comprehensive performance of the leather product, solves the problems of the existing leather manufacturing industry, and ensures that the leather product can keep soft for a long time and has moist hand feeling.)

1. A preparation method of a fatting agent for improving the softness of leather products is characterized in that castor oil is used as a raw material, and the fatting agent is prepared by organic modification, and comprises the following steps:

(1) sequentially adding the weighed 5.2-5.3 mmol of mercaptan, 7.5-8.0 ml of potassium permanganate solution and 25-30 ml of concentrated nitric acid into a three-neck flask provided with a thermometer, a stirrer and a condenser, heating to 80-90 ℃ under the protection of nitrogen, carrying out reflux stirring reaction for 1.5-2.0 hours, then adding 15-20 ml of ethanol into the flask, carrying out reaction for 40-50 minutes under the heating of a water bath at 60-70 ℃, adding a sodium carbonate buffer solution to adjust the pH value of a system to be 6.5-6.8 after the reaction is finished, pouring the product into ice water at 0-2 ℃, separating and purifying with ethyl acetate, washing with deionized water after liquid separation until the water layer is colorless, adding 15-20 g of anhydrous magnesium sulfate to remove residual water in the ethyl acetate phase, filtering to remove the magnesium sulfate, carrying out rotary evaporation to remove the ethyl acetate by using a rotary evaporator, placing the obtained product in a brown bottle, and sealing and storing the product in a cool and dry place for later use;

(2) adding 190-200 ml of castor oil into a clean flask, heating the mixture to 45-50 ℃ in a water bath, adding 4.2-4.3 g of the product obtained in the step (1) into the flask, starting a stirrer, adding 16-20 ml of azobisisobutyronitrile-ethanol solution and 1.0-1.2 g of tetramethylammonium chloride into the flask, continuously heating the mixture to 95-100 ℃, reacting for 3-4 hours, filtering to remove precipitates after the reaction is finished, and distilling under reduced pressure to remove the ethanol solvent to obtain an oily product, namely the fatting agent.

2. The method for preparing a fatliquor for improving the softness of leather products according to claim 1, wherein the molar concentration of the potassium permanganate solution in the step (1) is 0.8-0.9 mol/l.

3. The method for preparing a fatliquor for improving the softness of leather products according to claim 1, wherein the molar concentration of the concentrated nitric acid in the step (1) is 7.2-7.4 mol/l.

4. The method of claim 1, wherein the pH of the sodium carbonate buffer of step (1) is in the range of 8.8-9.0.

5. The method of claim 1, wherein the azobisisobutyronitrile-ethanol solution of step (2) has a mass concentration of azobisisobutyronitrile of 6.5-7.0%.

6. A method of preparing a fatliquor for increasing the softness of leather products according to claim 1, wherein the fatliquor is used at an optimal temperature of 40-45 ℃.

Technical Field

The invention belongs to the technical field of new material processing, and particularly relates to a preparation method of a fatting agent for improving the softness of a leather product.

Background

The leather is animal skin which is obtained by physical and chemical processing such as unhairing, tanning and the like and is denatured and non-perishable. The leather is formed by tightly weaving natural protein fibers in a three-dimensional space, and the surface of the leather is provided with a special grain surface layer which has natural grains and luster and comfortable hand feeling.

The processing process of the real leather is very complex, and dozens of working procedures are needed to prepare finished leather. Among them, leather greasing, also called oiling and oiling, is an important treatment process in the leather production process. Greatly influences the appearance and the inherent quality of the leather products. This is because the softness and physical and mechanical properties of tanned leather are changed, and without effective fatliquoring treatment, the leather fibers are dehydrated, causing local and even more severe cracking and loss of the application properties of leather. Therefore, the leather needs to be treated by adopting a proper fatting agent, the currently adopted fatting agent mainly comprises natural grease and a synthetic fatting agent, the natural grease has poor comprehensive performances such as weather resistance, mildew resistance and water resistance, and the synthetic fatting agent has good stability, but the fatting effect is general and the effect of improving the softness and the wear resistance of the leather product is not outstanding.

Disclosure of Invention

The invention aims to solve the existing problems and provides a preparation method of a fatting agent for improving the softness of leather products, which has the advantages of outstanding effect of fatting and leather formation, soft and plump leather surface, no residual oil spots, and the like, and also has the functions of improving the tanning property, the washing resistance, the light resistance and the like of the leather.

The invention is realized by the following technical scheme:

a preparation method of a fatting agent for improving the softness of leather products has the preferable scheme that castor oil is used as a raw material, organic modification is utilized to prepare the fatting agent, leather is treated, the treated leather is soft and not stiff, and the fatting and leather-forming effects are outstanding;

specifically, the preparation method of the fatting agent comprises the following steps:

the method comprises the following steps: sequentially adding the weighed 5.2-5.3 mmol of mercaptan, 7.5-8.0 ml of potassium permanganate solution and 25-30 ml of concentrated nitric acid into a three-neck flask provided with a thermometer, a stirrer and a condenser, heating to 80-90 ℃ under the protection of nitrogen, carrying out reflux stirring reaction for 1.5-2.0 hours, then adding 15-20 ml of ethanol into the flask, carrying out reaction for 40-50 minutes under the heating of a water bath at 60-70 ℃, adding a sodium carbonate buffer solution to adjust the pH value of a system to be 6.5-6.8 after the reaction is finished, pouring the product into ice water at 0-2 ℃, separating and purifying with ethyl acetate, washing with deionized water after liquid separation until the water layer is colorless, adding 15-20 g of anhydrous magnesium sulfate to remove residual water in the ethyl acetate phase, filtering to remove the magnesium sulfate, carrying out rotary evaporation to remove the ethyl acetate by using a rotary evaporator, placing the obtained product in a brown bottle, and sealing and storing the product in a cool and dry place for later use; the molar concentration of the potassium permanganate solution is 0.8-0.9 mol/L, and the molar concentration of the concentrated nitric acid is 7.2-7.4 mol/L; the pH value of the sodium carbonate buffer solution is in the range of 8.8-9.0.

Step two: adding 190-200 ml of castor oil into a clean flask, heating the mixture to 45-50 ℃ in a water bath, adding 4.2-4.3 g of the product obtained in the first step into the flask, starting a stirrer, adding 16-20 ml of azodiisobutyronitrile-ethanol solution and 1.0-1.2 g of tetramethylammonium chloride into the flask, continuously heating the mixture to 95-100 ℃, reacting for 3-4 hours, filtering to remove precipitates after the reaction is finished, and removing the ethanol solvent through reduced pressure distillation to obtain an oily product, namely the fatting agent. In the azobisisobutyronitrile-ethanol solution, the mass concentration of the azobisisobutyronitrile is 6.5-7.0%. The optimal using temperature of the fatting agent is 40-45 ℃. The prepared fatting agent is based on natural vegetable oil, after modification treatment, the comprehensive performances such as light resistance and weather resistance are obviously improved, a filling binding layer can be formed in the leather gap in the fatting process, the tensile strength is greatly improved, the energy between interfaces is changed, the surface of the leather is protected from being influenced by the outside, and the problems of pollution, damage and the like are avoided.

Compared with the prior art, the invention has the following advantages: in order to solve the problem that the application effect of the existing fatting agent on the processing of leather products is general, the invention provides a preparation method of the fatting agent for improving the softness of the leather products, castor oil is used as a raw material, the fatting agent is prepared by organic modification, the leather is treated, the treated leather is soft and not stiff, the fatting and leather-forming effect is outstanding, the leather surface is soft and full, no oil spots are left, and the fatting agent also has the functions of improving the tanning property, washing resistance, light resistance and the like of the leather, can improve the softness and wear resistance of the leather products, and also has the waterproof and mildewproof effects; the leather is endowed with excellent texture hand feeling, the fatting agent has high chemical stability, low preparation cost, excellent leather applicability and no damage to leather, and simultaneously, the service life of a leather product can be prolonged, and economic benefits and environmental protection benefits are realized; the invention can obviously improve the comprehensive performance of the leather product, solves the problems of the existing leather manufacturing industry, and ensures that the leather product can keep soft for a long time and has moist hand feeling. The invention effectively solves the problem of poor application effect of the existing fatting agent in leather product production, has other compound effects besides the function of fatting and softening leather, improves the elasticity and luster of the leather, avoids crease, reduces the damage rate, is beneficial to the maintenance of the leather product, can realize the practical significance of promoting the development of the leather product processing industry and improving the market competitiveness, has higher value for the research and application of the fatting agent material, obviously promotes the rapid development and the sustainable development of resources in the field of leather matching industrial material research, and is a technical scheme which is extremely worthy of popularization and use.

Detailed Description

In order to make the objects, technical solutions and effects of the present invention clearer and clearer, the present invention is further described with reference to specific embodiments, and it should be understood that the specific embodiments described herein are only used for explaining the present invention and are not used for limiting the technical solutions provided by the present invention.