Polyether modified silicone oil hydrophobic retanning fatliquor as well as preparation method and application thereof

Abstract

The invention discloses a polyether modified silicone oil hydrophobic retanning fatliquor as well as a preparation method and application thereof, and belongs to the technical field of leather chemical industry. The preparation method comprises the following steps: preparing polyether modified silicone oil from end hydrogen-containing silicone oil and allyl polyether as raw materials, uniformly dispersing the polyether modified silicone oil, an emulsifier and water to obtain a water-in-oil emulsion, adding water into the water-in-oil emulsion, uniformly dispersing to obtain an oil-in-water mixture, adding deracetam BTL, and uniformly dispersing to obtain the deracetam emulsion. The tensile strength, the tearing strength and the hydrophobic effect of leather treated by the polyether modified silicone oil hydrophobic retanning fatliquor are remarkably improved, the complete infiltrating time of the leather can reach 10 min, meanwhile, it can be guaranteed that the leather has good softness, and the additional value of the leather can be increased.

Description

Technical Field

[0001] The invention belongs to the technical field of leather chemical industry, and particularly relates to a polyether modified silicone oil hydrophobic retanning fatliquor and a preparation method and application thereof. Background Art

[0002] In the leather manufacturing process, retanning and fatliquoring are indispensable processes, which have a significant effect on the performance and added value of finished leather. In the current leather technology, most of the retanning and fatliquoring processes are carried out using separate retanning agents and fatliquoring agents, which are complicated to operate. Therefore, a retanning and fatliquoring agent having a retanning and fatliquoring effect is important for shortening the leather manufacturing process and improving the competitiveness of leather products. However, the existing retanning and fatliquoring agents on the market are mainly polymers composed of a C—C bond as the main chain and a hydrophilic side chain group. A novel amphiphilic copolymer retanning and fatliquoring agent and a preparation method are disclosed in the prior art. The retanning and fatliquoring agent is only applicable to wet blue leather and has general waterproof performance. A preparation method of a retanning and fatliquoring agent is also disclosed in the prior art. The retanning and fatliquoring effect of the retanning and fatliquoring agent is insufficient, the crust leather is relatively stiff, and the finished leather has general hydrophobicity.

[0003] Hydrophobic treatment of leather significantly improves its mechanical properties and tactile comfort, thereby increasing its economic value. Current leather hydrophobic treatment technologies often utilize organic phases for hydrophobic treatment. These organic phases are highly volatile and environmentally polluting, easily causing ecological pollution. This is detrimental to the clean production of leather, and makes subsequent dyeing and other operations difficult, resulting in reduced dye uptake. Furthermore, hydrophobic spraying can be applied to the finished leather surface to achieve a hydrophobic effect. However, this results in a non-wear-resistant hydrophobic surface and poor internal hydrophobicity, making it impossible to maintain full hydrophobicity within the leather.

[0004] Therefore, it is necessary to develop tanning chemicals with good hydrophobicity and environmental friendliness to improve the overall performance of leather products. This is of great significance for the clean production of my country's tanning industry and the improvement of leather quality. Summary of the Invention

[0005] In response to the above-mentioned prior art, the present invention discloses a polyether-modified silicone oil hydrophobic retanning fatliquor and its preparation method and application, in order to solve the technical problems that the preparation method of the retanning fatliquor in the prior art is not environmentally friendly and the leather has poor hydrophobic effect, hard texture and poor mechanical properties after use.

[0006] In order to achieve the above object, the technical solution adopted by the present invention is: to provide a preparation method of a polyether-modified silicone oil hydrophobic retanning fatliquor, which comprises the following steps: S1: dissolving a hydrogen-terminated silicone oil with a molecular weight of 4000-5000 g / mol and an allyl polyether with a molecular weight of 500-1000 g / mol in a solvent, adding a metal catalyst, and stirring to react to obtain a polyether-modified silicone oil; S2: Mixing polyether-modified silicone oil, emulsifier and water, heating and stirring until uniform, to obtain a water-in-oil emulsion; S3: Add water to the water-in-oil emulsion under heating and stirring conditions, stir and disperse for 0.5 to 1 hour to obtain a water-in-oil mixture, and then continue to add the penetrant under heating and stirring conditions, and stir and disperse for 0.5 to 1 hour to obtain the mixture.

[0007] On the basis of the above technical solution, the present invention can also be improved as follows.

[0008] Furthermore, in step S1, the solvent is isopropanol; the metal catalyst is a chloroplatinic acid catalyst with a Pt content of 1 wt%; and the material-liquid ratio of the hydrogen-terminated silicone oil, the allyl polyether, the solvent, and the metal catalyst is 50-100 g: 20-50 g: 100-120 g: 1 g.

[0009] Furthermore, in step S1, the stirring speed is 400-600 r / min, the reaction temperature is 50-70° C., and the reaction time is 2-3 h.

[0010] Furthermore, in step S2, the emulsifier is prepared by mixing Span 80 and Tween 80 at a weight ratio of 0.55:0.45.

[0011] Furthermore, in step S2, the mass ratio of polyether-modified silicone oil, emulsifier and water is 20-35:10-20:0.3-3.

[0012] Furthermore, in step S2 and step S3, the heating temperature is 50-55° C., and the stirring speed is 1000-1200 r / min.

[0013] Furthermore, the penetrant in step S3 is Desaytan BTL; and the mass ratio of the water-in-oil emulsion, water, and penetrant is 30-55:200-350:10-20.

[0014] The invention also discloses application of the polyether modified silicone oil hydrophobic retanning fatliquor in leather processing.

[0015] The beneficial effects of the present invention are: 1. The polyether-modified silicone oil hydrophobic retanning fat-liquor preparation process of the present invention is simple. According to the molecular weight of the adjusted end-containing hydrogen silicone oil and the allyl polyether, a retanning fat-liquor with different hydrophilicity is obtained to regulate and control hydrophobicity. The part with better hydrophilicity will enter the layer inside the fiber, and the part with better hydrophobicity will form a hydrophobic layer outside to give leather good hydrophobicity. It can be applied to different types of leather and also ensure hydrophobic fat-liquor and retanning effect, and good hydrophobicity is all arranged on different levels. Polyether-modified silicone oils of different molecular weights can be filled into different pores inside the leather, and their retanning effect is also ensured in the fat-liquor process; the addition of polyether groups promotes the compatibility of retanning fat-liquor with other tanning chemicals, thereby optimizing the retanning process and ensuring that the retanning fat-liquor effect is uniform.

[0016] 2. The retanning fatliquor has good biodegradability. The tensile strength, tear strength, softness and hydrophobic effect of the leather treated with the retanning fatliquor of the present invention are significantly improved. The complete infiltration time of the leather can reach 10 minutes, which is beneficial to improving the added value of the leather. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a comparison chart of leather tear strength test results; Figure 2 This is a comparison chart of leather tensile strength test results; Figure 3 This is a comparison chart of the initial contact angle test results for leather; Figure 4 This is a comparison chart of the time it takes for leather to be completely soaked; Figure 5 This is a comparison chart of leather softness test results; Figure 6 This is a graph showing the test results of the complete wetting time of leather after treatment with the retanning fatliquor in Examples 1-2 and Comparative Examples 1-2. DETAILED DESCRIPTION

[0018] Desoaten BTL was purchased from Desaier New Material Technology Co., Ltd., product model DESOATEN BTL; the commercially available fatliquor in the control group was purchased from Desaier New Material Technology Co., Ltd., product model DESOPONSO, and the commercially available acrylic resin retanning agent was purchased from Taizhou Keli Biotechnology Co., Ltd.

[0019] The specific implementation methods of the present invention are described in detail below with reference to the embodiments.

[0020] Example 1 A polyether-modified silicone oil hydrophobic retanning fatliquor, the preparation method of which comprises the following steps: S1: Add 100 g of terminal hydrogenated silicone oil with a molecular weight of 5000, 20 g of allyl polyether with a molecular weight of 500 g / mol, 120 g of isopropyl alcohol, and 1 g of chloroplatinic acid catalyst with a Pt content of 1 wt% into a reactor, and stir the mixture at 60°C, 500 r / min, and nitrogen atmosphere for 3 h. After the reaction is completed, the reaction solution is cooled to room temperature, and the isopropyl alcohol is removed by vacuum distillation to obtain polyether-modified silicone oil; S2: Add 20 g of polyether-modified silicone oil, 10 g of emulsifier (5.5 g of Span 80 + 4.5 g of Tween 80), and 3 g of water into a homogenizer and mix thoroughly at 50°C and 1000 rpm to obtain a water-in-oil emulsion. S3: Continue to add 200g of water to the oil-in-water emulsion at 50°C and 1000r / min, stir and disperse for 1h to obtain a water-in-oil mixture, and then continue to add 10g of Desaytan BTL at 50°C and 1000r / min, stir and disperse for 1h to obtain the mixture.

[0021] Example 2 S1: Add 100 g of terminal hydrogenated silicone oil with a molecular weight of 4000, 20 g of allyl polyether with a molecular weight of 1000 g / mol, 120 g of isopropyl alcohol, and 1 g of chloroplatinic acid catalyst with a Pt content of 1 wt% into a reactor, and stir the mixture at 60°C, 500 r / min, and nitrogen atmosphere for 3 h. After the reaction is completed, the reaction solution is cooled to room temperature, and the isopropyl alcohol is removed by vacuum distillation to obtain polyether-modified silicone oil; S2: Add 35 g of polyether-modified silicone oil, 20 g of emulsifier (11 g of Span 80 + 9 g of Tween 80), and 1 g of water into a homogenizer and mix thoroughly at 50°C and 1000 rpm to obtain a water-in-oil emulsion. S3: Continue to add 350g of water to the water-in-oil emulsion at 50°C and 1000r / min, stir and disperse for 1h to obtain an oil-in-water mixture, and then continue to add 20g of Desaytan BTL at 50°C and 1000r / min, stir and disperse for 1h to obtain the mixture.

[0022] Example 3 S1: Add 50 g of terminal hydrogenated silicone oil with a molecular weight of 5000, 50 g of allyl polyether with a molecular weight of 500 g / mol, 100 g of isopropyl alcohol, and 1 g of chloroplatinic acid catalyst with a Pt content of 1 wt% into a reactor, and stir the mixture at 50°C, 600 r / min, and nitrogen atmosphere for 2 h. After the reaction is completed, the reaction solution is cooled to room temperature, and the isopropyl alcohol is removed by vacuum distillation to obtain polyether-modified silicone oil; S2: Add 30 g of polyether-modified silicone oil, 10 g of emulsifier (5.5 g of Span 80 + 4.5 g of Tween 80), and 0.3 g of water into a homogenizer and mix thoroughly at 55°C and 1200 rpm to obtain a water-in-oil emulsion. S3: Add 300 g of water to the water-in-oil emulsion at 55°C and 1200 r / min, and stir and disperse for 0.5 h to obtain an oil-in-water mixture. Then, add 15 g of Desaytan BTL at 55°C and 1200 r / min, and stir and disperse for 0.5 h to obtain the mixture.

[0023] Example 4 A polyether-modified silicone oil hydrophobic retanning fatliquor, the preparation method of which comprises the following steps: S1: Add 70g of terminal hydrogenated silicone oil with a molecular weight of 5000, 30g of allyl polyether with a molecular weight of 500g / mol, 100g of isopropyl alcohol and 1g of chloroplatinic acid catalyst with a Pt content of 1wt% into a reactor, and stir the mixture at 70°C, 400r / min and nitrogen atmosphere for 2.5h. After the reaction is completed, the reaction solution is cooled to room temperature, and the isopropyl alcohol is removed by vacuum distillation to obtain polyether-modified silicone oil; S2: Add 20 g of polyether-modified silicone oil, 10 g of emulsifier (5.5 g of Span 80 + 4.5 g of Tween 80), and 0.8 g of water into a homogenizer and mix thoroughly at 50°C and 1000 rpm to obtain a water-in-oil emulsion. S3: Continue to add 250g of water to the oil-in-water emulsion at 50°C and 1000r / min, stir and disperse for 1h to obtain a water-in-oil mixture, and then continue to add 15g of Desaytan BTL at 50°C and 1000r / min, stir and disperse for 1h to obtain the mixture.

[0024] Comparative Example 1 A polyether-modified silicone oil hydrophobic retanning fatliquor, which differs from Example 1 in that the polyether-modified silicone oil is synthesized from a terminal hydrogen-containing silicone oil with a molecular weight of 3000 g / mol and an allyl polyether with a molecular weight of 1500 g / mol.

[0025] Comparative Example 2.

[0026] A polyether-modified silicone oil hydrophobic retanning fatliquor, which differs from Example 1 in that the polyether-modified silicone oil is synthesized from a terminal hydrogen-containing silicone oil with a molecular weight of 2000 g / mol and an allyl polyether with a molecular weight of 2000 g / mol.

[0027] Experimental example ① Chrome tanned leather was retanned and fatliquored using the retanning and fatliquor prepared in Example 1 (dosage: 10% of tare weight) and the control retanning and fatliquor (dosage: 10% of tare weight, mass ratio of commercial acrylic resin retanning agent to commercial fatliquor: 1:1), respectively. After the fatliquoring is completed, the leather is dried and softened. After balancing for two days, the leather performance is tested using a tensile testing machine, a softness tester, and a contact angle tester. Figures 1 to 4 As shown. Figures 1 and 2 It can be seen that after the leather is treated with the retanning fatliquor prepared in the present invention, the leather tensile strength and tear strength are higher; Figures 3 and 4 The initial contact angle of the leather treated with the retanning and fatliquor prepared in the present invention is significantly higher than that of the control group treated with the traditional retanning and fatliquor combination, the adhesion of water or oil stains can be effectively reduced, the anti-fouling performance of the leather is significantly improved, and the complete infiltration time is significantly improved. The complete infiltration time after treatment with the traditional retanning and fatliquor is about 40 seconds. After the leather is sliced ​​into three layers, the complete infiltration time of the middle layer is only about 30 seconds. After treatment with the retanning and fatliquor prepared in the present invention, the complete infiltration time of the leather surface is 10 minutes, and the infiltration time of the middle layer is 8 minutes. The long infiltration time can maintain the clean state of the leather product itself, reduce the adhesion of pollutants, and is conducive to the production of high-value-added leather products.

[0028] The polyether silicone oil in the retanning fatliquor has a large number of hydrophilic ether bonds at both ends, forming a water-in-oil structure in the early stage of fatliquor. Under the action of mechanical force, it enters the interior of the leather. As the fatliquor process proceeds, the silicone oil concentration inside and outside the leather reaches equilibrium, and then acid is added to fix the silicone oil. After the fatliquor is completed, the leather is dried and softened. During the drying process, as the water content decreases, the unstable silicone oil emulsion inside the leather breaks up and combines with the leather fibers and wraps around the surface of the leather fibers to form a hydrophobic film. At the same time, because the polyether silicone oil used is a polydispersed polyether silicone oil, the large molecular silicone oil molecules will precipitate in the middle of the pores of the fibers, increasing the fullness of the leather, thereby achieving the purpose of retanning; at the same time, the small molecular silicone oil will enter the deeper fibers of the leather with the assistance of the penetrant, achieving good softness and comprehensive hydrophobic effect. The leather produced by this retanning fatliquor has good softness and hydrophobic effect because Si-O chains with good flexibility and hydrophobic effect are introduced on the basis of the traditional CC main chain. Compared with traditional retanning fatliquors, such as Figure 5 As shown, the leather after treatment is more soft and less prone to hardening.

[0029] ② The chrome tanned leather was retanned and fat-liquored using the retanning and fat-liquoring agents in Examples 1 and 2 and the leather performance test results after treatment were as follows: Figure 6 As shown, it can be seen from the figure that the leather hydrophobic effect is better during implementation.

[0030] Although the specific embodiments of the present invention have been described in detail in conjunction with the embodiments, this should not be construed as limiting the scope of protection of this patent. Within the scope described by the claims, various modifications and variations that can be made by those skilled in the art without creative work still fall within the scope of protection of this patent.

Claims

1. A method for preparing a polyether-modified silicone oil hydrophobic retanning fatliquor, characterized in that: The following steps are involved: S1: dissolving a hydrogen-terminated silicone oil with a molecular weight of 4000-5000 g / mol and an allyl polyether with a molecular weight of 500-1000 g / mol in a solvent, adding a metal catalyst, and stirring to react to obtain a polyether-modified silicone oil; S2: mixing the polyether-modified silicone oil, emulsifier and water, heating and stirring until uniform, to obtain a water-in-oil emulsion; S3: adding water to the water-in-oil emulsion under heating and stirring conditions, stirring and dispersing for 0.5 to 1 hour to obtain an oil-in-water mixture, and then continuing to add the penetrant under heating and stirring conditions, stirring and dispersing for 0.5 to 1 hour to obtain the mixture.

2. The preparation method of the polyether-modified silicone oil hydrophobic retanning fatliquor according to claim 1, wherein: In step S1, the solvent is isopropanol; the metal catalyst is a chloroplatinic acid catalyst with a Pt content of 1 wt%; the material-liquid ratio of the end-hydrogenated silicone oil, the allyl polyether, the solvent, and the metal catalyst is 50-100 g: 20-50 g: 100-120 g: 1 g.

3. The preparation method of the polyether-modified silicone oil hydrophobic retanning fatliquor according to claim 1, wherein: In step S1, the stirring speed is 400-600 r / min, the reaction temperature is 50-70° C., and the reaction time is 2-3 h.

4. The preparation method of the polyether-modified silicone oil hydrophobic retanning fatliquor according to claim 1, wherein The emulsifier in step S2 is prepared by mixing Span 80 and Tween 80 in a weight ratio of 0.55:0.

45.

5. The preparation method of the polyether-modified silicone oil hydrophobic retanning fatliquor according to claim 4, wherein In step S2, the mass ratio of polyether-modified silicone oil, emulsifier and water is 20-35:10-20:0.3-3.

6. The preparation method of the polyether-modified silicone oil hydrophobic retanning fatliquor according to claim 4, characterized in that, In step S2 and step S3, the heating temperature is 50-55° C., and the stirring speed is 1000-1200 r / min.

7. The preparation method of the polyether-modified silicone oil hydrophobic retanning fatliquor according to claim 4, wherein The penetrant in step S3 is Desaytan BTL; the mass ratio of the water-in-oil emulsion, water, and penetrant is 30-55:200-350:10-20.

8. A polyether-modified silicone oil hydrophobic retanning fatliquor, characterized in that: The polyether-modified silicone oil hydrophobic retanning fatliquor is prepared by the preparation method of any one of claims 1 to 7.

9. An application of a polyether-modified silicone oil hydrophobic retanning fatliquor, characterized in that: Use of the polyether-modified silicone oil hydrophobic retanning fatliquor according to claim 8 in leather processing.

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