A microemulsion leather degreasing agent and its preparation method

Abstract

The invention belongs to the field of leather manufacturing and processing, discloses a microemulsion leather degreasing agent and a preparation method thereof, a disclosed microemulsion leather degreasing agent and a preparation method thereof adopt nonionic surfactant, anionic surfactant, short-chain alcohol, turpentine as raw materials, first nonionic surfactant, anionic surfactant, short-chain alcohol, turpentine are mixed in proportion, and then NaCl solution is slowly added dropwise thereto and stirred until a transparent and uniform solution is formed to obtain the microemulsion leather degreasing agent. The present invention uses anionic surfactant and nonionic surfactant in combination to prepare a microemulsion leather degreasing agent, the degreasing agent has lower surface tension, can effectively reduce the oil content of crust leather, and the preparation method is simple, raw materials are easily available, conditions are mild, low energy consumption, and has good application prospects.

Description

Technical Field

[0001] The invention belongs to the field of leather manufacturing and processing, and particularly relates to a microemulsion leather degreasing agent and a preparation method thereof. Background Art

[0002] With the improvement of living standards, people's demand for high-end leather products continues to increase, and improving leather quality has attracted more and more attention. Among them, the degree of removal of natural fat from the skin has a significant impact on the quality of the final leather. Incomplete removal of fat from the skin will affect the dispersion, penetration and bonding of materials used in the subsequent tanning process within the leather, affecting the uniformity of leather dyeing. At the same time, if the fat removal rate from the skin is low during the tanning process, it will also cause the fat that has not been removed from the finished leather to migrate to the leather surface, forming oil frost. In addition, green and sustainable production is an important strategic goal of national development. Therefore, it is urgent to develop a green and environmentally friendly degreasing agent with good degreasing effect.

[0003] Enzymes have attracted widespread attention and application in degreasing agent research due to their high efficiency, non-toxicity, and biodegradability. However, enzymes are relatively expensive and have strict environmental requirements, making them difficult to use on a large scale. Degreasing with surfactants is simple and has low production risks, but single surfactants are not ideal, and wastewater can easily cause environmental pollution. Microemulsions offer the advantages of surfactant degreasing while reducing the use of surfactants and reducing environmental pollution. Microemulsions have been extensively studied in oilfields, food processing, and other fields, but their application in leather degreasing is less common. Summary of the Invention

[0004] The invention discloses a microemulsion leather degreasing agent and a preparation method thereof, aiming to fill the gap in the application of microemulsion in leather degreasing.

[0005] The technical solution adopted in the present invention is:

[0006] A microemulsion leather degreasing agent comprises, by system mass percentage, 8-10% of an oil phase, 25-35% of a surfactant, 20-30% of a co-surfactant, and the remainder being an aqueous phase, wherein the surfactants are nonionic surfactants and anionic surfactants, and the aqueous phase is a sodium chloride solution.

[0007] A preparation method of the microemulsion leather degreasing agent as described above comprises the following steps: firstly mixing a surfactant, a cosurfactant and an oil phase in proportion, then slowly adding a NaCl solution thereto and stirring evenly until a transparent and uniform solution is formed, thereby obtaining the microemulsion leather degreasing agent.

[0008] Furthermore, the ratio of surfactant to co-surfactant is 1:(0.5-2).

[0009] Furthermore, the surfactant is one or more of Span-80, alkyl polyoxyethylene ether APE, sodium dodecylbenzene sulfonate, Tween-60, and sodium dodecylsulfonate.

[0010] Furthermore, the co-surfactant is one or more of ethanol, n-butanol, isobutanol, isopropanol, and n-pentanol.

[0011] Furthermore, the oil phase is turpentine.

[0012] The present invention has the following advantages:

[0013] 1. The microemulsion leather degreasing agent provided by the present invention has low surface tension and high surface activity, and can effectively reduce the oil content of crust leather. Specifically, the surface tension is reduced to below 30mN / m.

[0014] 2. The preparation method of the microemulsion leather degreasing agent provided by the present invention uses a compound of anionic surfactant and nonionic surfactant. The preparation method is simple, the raw materials are readily available, the conditions are mild, the energy consumption is low, and it has good application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 This is a surface tension curve diagram of the microemulsion leather degreasing agent provided by the present invention at 25°C. DETAILED DESCRIPTION

[0016] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention will be described in detail below with reference to the accompanying drawings and embodiments.

[0017] A microemulsion leather degreasing agent comprises, by system mass percentage, 8-10% of an oil phase, 25-35% of a surfactant, 20-30% of a co-surfactant, and the remainder being an aqueous phase, wherein the surfactants are nonionic surfactants and anionic surfactants, and the aqueous phase is a sodium chloride solution.

[0018] A method for preparing the microemulsion leather degreasing agent as described above comprises first mixing a surfactant, a cosurfactant, and an oil phase in a suitable proportion, then slowly adding a NaCl solution dropwise thereto and stirring until a transparent, uniform solution is formed, thereby obtaining the microemulsion leather degreasing agent. The ratio of surfactant to cosurfactant is 1:(0.5-2).

[0019] Example 1:

[0020] A microemulsion leather degreasing agent and a preparation method thereof. The microemulsion leather degreasing agent comprises, by mass percentage, 8% oil phase, the balance aqueous phase, 25% surfactant, and 25% cosurfactant. During preparation, the oil phase, surfactant, and cosurfactant are mixed, and the aqueous phase is then added dropwise until the system becomes homogeneous and transparent, thereby forming the microemulsion leather degreasing agent. The oil phase is turpentine, and the surfactants are Span-80 and alkyl polyoxyethylene ether (APE). The cosurfactant is ethanol, and the surfactant to cosurfactant ratio is 1:1. The aqueous phase is a sodium chloride solution.

[0021] Example 2:

[0022] A microemulsion leather degreasing agent and its preparation method. The microemulsion leather degreasing agent comprises, by mass percentage, 8% oil phase, the balance aqueous phase, 40% surfactant, and 20% cosurfactant. During preparation, the oil phase, surfactant, and cosurfactant are mixed, and the aqueous phase is then added dropwise until the system becomes homogeneous and transparent, thereby forming the microemulsion leather degreasing agent. The oil phase is turpentine, and the surfactants are Tween-60 and sodium dodecylbenzenesulfonate. The cosurfactant is n-pentanol, and the ratio of surfactant to cosurfactant is 2:1. The aqueous phase is a sodium chloride solution.

[0023] Example 3:

[0024] A microemulsion leather degreasing agent and its preparation method. The microemulsion leather degreasing agent comprises, by mass percentage, 9% oil phase, the balance aqueous phase, 35% surfactant, and 24% cosurfactant. During preparation, the oil phase, surfactant, and cosurfactant are mixed, and the aqueous phase is then added dropwise until the system becomes homogeneous and transparent, thereby forming the microemulsion leather degreasing agent. The oil phase is turpentine, and the surfactants are Tween-60 and sodium lauryl sulfate. The cosurfactant is isopropyl alcohol, with a surfactant to cosurfactant ratio of 3:2. The aqueous phase is a sodium chloride solution.

[0025] Example 4:

[0026] A microemulsion leather degreasing agent and its preparation method. The microemulsion leather degreasing agent comprises, by mass percentage, 9% oil phase, the balance aqueous phase, 40% surfactant, and 20% cosurfactant. During preparation, the oil phase, surfactant, and cosurfactant are mixed, and then the aqueous phase is added dropwise until the system becomes homogeneous and transparent, thereby forming the microemulsion leather degreasing agent. The oil phase is turpentine, and the surfactants are alkyl polyoxyethylene ether (APE) and sodium lauryl sulfate. The cosurfactant is n-butanol, and the ratio of surfactant to cosurfactant is 2:1. The aqueous phase is a sodium chloride solution.

[0027] Example 5:

[0028] A microemulsion leather degreasing agent and its preparation method. The microemulsion leather degreasing agent comprises, by mass percentage, 10% oil phase, the balance aqueous phase, 27% surfactant, and 27% cosurfactant. During preparation, the oil phase, surfactant, and cosurfactant are mixed, and then the aqueous phase is added dropwise until the system becomes homogeneous and transparent, thereby forming the microemulsion leather degreasing agent. The oil phase is turpentine, and the surfactants are Span-80 and Tween-60. The cosurfactant is isobutanol, with a surfactant to cosurfactant ratio of 1:1. The aqueous phase is a sodium chloride solution.

[0029] The microemulsion leather degreasing agent prepared by the present invention has high surface activity and can reduce the surface tension to below 30mN / m. Figure 1 Table 1 shows the degreasing results of the microemulsion leather degreasing agents prepared in the above examples on fatty sheep acid leather compared with the results of commercially available samples.

[0030] Table 1: Degreasing results of microemulsion leather degreasing agent on fatty sheep acid leather

[0031] Commercially available samples Example 1 Example 2 Example 3 Example 4 Example 5 Degreasing rate / % 64.63 69.01 67.24 67.17 70.34 69.18

[0032] The above embodiments are merely intended to further describe the present invention in detail, but should not be construed as limiting the scope of the present invention to the above embodiments. Various substitutions and modifications made based on common technical knowledge and conventional means in the art without departing from the above technical concept of the present invention are intended to be included within the scope of protection of the present invention.

Claims

1. A microemulsion leather degreasing agent, characterized in that: Calculated by system mass percentage, it includes 8-10% oil phase, 25-35% surfactant, 20-30% co-surfactant, and the balance is aqueous phase, wherein the surfactant is a nonionic surfactant and an anionic surfactant, and the aqueous phase is a sodium chloride solution; The preparation method of the microemulsion leather degreasing agent is as follows: firstly, a surfactant, a cosurfactant and an oil phase are mixed in proportion, and then a NaCl solution is slowly added dropwise thereto and stirred evenly until a transparent and uniform solution is formed, thereby obtaining the microemulsion leather degreasing agent; The ratio of surfactant to cosurfactant is 1:(0.5~2); The surfactant is a variety of Span-80, alkyl polyoxyethylene ether APE, sodium dodecylbenzene sulfonate, Tween-60, and sodium dodecyl sulfonate; The co-surfactant is one or more of ethanol, n-butanol, isobutanol, isopropanol, and n-pentanol; The oil phase adopts turpentine.

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