CN103103795A - Method for preparing leather finishing agent from polyether polyurethane emulsion - Google Patents

Abstract

The invention relates to a preparation method of a polyether type polyurethane emulsion leather finishing agent. The comprehensive performance of the existing coating agent is not enough. The method of the invention first prepares the polyether type polyurethane emulsion and the finishing agent solution respectively, and then mechanically mixes them uniformly at a weight ratio of 100:5-10. The preparation method of polyether polyurethane emulsion is to add toluene diisocyanate and catalyst into dehydrated polyoxyethylene diol, add N-methyldiethanolamine to continue the reaction after the reaction, adjust the pH value to 5-7, and then add acetone and deionized water. The preparation method of the finishing agent solution is to add hydroxyethyl cellulose to the sodium hydroxide solution, add glycidyl trimethyl ammonium chloride to react, adjust the pH value to 6-7, wash and dry the solid product, and mix with Polyvinylpyrrolidone was added together to dissolve in deionized water. The process of the method of the invention is relatively simple, and the prepared leather finishing agent not only has excellent comprehensive performance, but also has good antibacterial performance.

Description

A kind of preparation method of polyether type polyurethane emulsion leather finishing agent

technical field

The invention belongs to the technical field of leather chemistry and relates to a preparation method of a leather finishing agent, in particular to a preparation method of a polyether polyurethane emulsion leather finishing agent.

Background technique

Leather finishing agent is an important leather chemical that improves the appearance, performance and economic value of leather. After finishing the leather with a finishing agent, a uniform film protective layer is formed on the surface of the leather, which endows the leather with excellent performance such as solvent resistance, flex resistance, wet and dry rub resistance, impact resistance and water resistance. With the development of science and technology, people's demand for leather quality is getting higher and higher, and the quality of leather depends largely on the quality of leather finishing agent.

At present, leather finishing agents mainly include nitrocellulose finishing agents, polybutadiene finishing agents, acrylic resin finishing agents, polyurethane finishing agents, silicone finishing agents and corresponding modified products, among which water-based polyurethane finishing agents and their modified products are The research focus of many scientific researchers is also the main direction for the development of leather finishing agents in the future. As early as 1972, the German Bayer company officially used polyurethane water dispersion as leather finishing. my country began to study the application of water-based polyurethane finishing agents in leather from the 1970s. Shenyang Leather Research Institute, Tianjin Leather Research Institute, Anhui University, Chenguang Chemical Research Institute, etc. have successfully developed water-based polyurethane leather finishing agents. Water-based polyurethane leather finishing agent is non-toxic, non-polluting, and has strong film-forming ability during use. It has excellent cold resistance, elasticity, and comfortable and natural feel. O first-class hydrophilic group, the formed coating film is not resistant to wet rubbing, and the mechanical strength and gloss of the coating film are not high. In recent years, many scholars at home and abroad have carried out a lot of improvement research on water-based polyurethane leather finishing agents. Wang Nan invented a polyurethane-polyacrylate composite leather finishing agent (Chinese invention patent CN1046952C), which composites polyurethane emulsion and polyacrylate emulsion. Cross-linking and forming a core-shell structure, the obtained leather finishing agent has better elasticity and strength. Li Wei, Qin Shufa, Zheng Xuejing, Tang Keyong, Wang Quanjie, etc. proposed a collagen-modified polyurethane leather finishing agent (Polymer Materials Science and Engineering 2008, Vol.24, No.5), through more amino groups on collagen, The carboxyl group and imino group undergo grafting reaction with the active groups of polyurethane to utilize the natural characteristics of collagen and improve the performance of polyurethane coating agents. Dong Wei, Chen Zheng, Xin Zhongyin, Wu Yangyuan, etc. (Leather Science and Engineering 2011, Vol.21, No.4) prepared epoxy resin modified waterborne polyurethane coating agent by mechanical blending method, which improved the coating film Excellent tensile strength, water resistance, water resistance, solvent resistance, acid resistance, alkali resistance and salt resistance. However, these leather finishing agents have deficiencies in the adhesion, leveling, etc. of the bottom layer, especially the hygienic performance cannot meet people's requirements.

Contents of the invention

The object of the present invention aims at the deficiencies of the prior art, and provides a method for preparing a polyether polyurethane emulsion leather finishing agent with good comprehensive performance, especially hygienic and bactericidal performance.

In order to solve the problems of the technologies described above, the method steps adopted in the present invention are as follows:

The method of the present invention firstly prepares polyether type polyurethane emulsion and finishing agent solution respectively, and then mechanically mixes polyether type polyurethane emulsion and finishing agent solution according to the weight ratio of 100:5-10, which has good comprehensive performance and hygienic sterilization Cationic polyether polyurethane emulsion leather finishing agent.

The preparation method of described polyether polyurethane emulsion is:

Dehydrate 30-40 parts by weight of polyoxyethylene diol under vacuum conditions at 110-120°C for 1-2 hours, then lower the temperature to 50-70°C; ～15 parts of toluene diisocyanate and 0.01～0.5 parts of catalyst are added to the dehydrated polyoxyethylene glycol, reacted at 75～85°C for 2～3 hours, and then lowered the temperature to 30～40°C; the number of parts by weight is 3 ～6 parts of N-methyldiethanolamine, react at 60～65℃ for 2～4 hours, then lower the temperature to 40～50℃; add glacial acetic acid to adjust the pH value to 5～7, and then add 20～100 parts by weight 1 part of acetone for dilution, then add 80 to 100 parts by weight of deionized water for high-speed emulsification, and vacuum remove the acetone solvent to obtain a polyether polyurethane emulsion;

The catalyst is dibutyltin dilaurate or stannous octoate.

The preparation method of described finishing agent solution is:

Add 1 to 3 parts by weight of hydroxyethyl cellulose into 20 to 40 parts by weight of sodium hydroxide solution with a concentration of 1.0 to 2.0M, stir and dissolve at room temperature; add 5 parts by weight ～10 parts of glycidyltrimethylammonium chloride, stir evenly, heat up to 80～85°C, react for 5～10 hours; adjust the pH value of the reaction system to 6～7 with hydrochloric acid, and obtain a solid product after filtration; After the solid product is washed and vacuum-dried, powdered hydroxyethyl cellulose quaternary ammonium salt is obtained; 1 to 5 parts by weight of hydroxyethyl cellulose quaternary ammonium salt and 10 to 20 parts of polyvinylpyrrolidone are added to the weight part Dissolve in 100 parts of deionized water, and stir well to obtain the finishing agent solution.

The glycidyl trimethyl ammonium chloride used in the inventive method has good antibacterial properties, and the hydroxyethyl cellulose quaternary ammonium salt that glycidyl trimethyl ammonium chloride is combined with hydroxyethyl cellulose not only It has good antibacterial properties and can promote the firm combination of leather finishing agents and leather fibers. The process of the method of the invention is relatively simple, and the prepared leather finishing agent has excellent comprehensive performance and hygienic and bactericidal performance.

Detailed ways

Prepare polyether polyurethane emulsion and finishing agent solution respectively.

The specific example of preparing polyether type polyurethane emulsion is as follows:

Example 1-1.

Dehydrate 3kg of polyoxyethylene diol under vacuum at 110°C for 1 hour, then lower the temperature to 50°C; add 1kg of toluene diisocyanate and 1g of dibutyltin dilaurate under nitrogen protection, and react at 75°C 3h, then lower the temperature to 30°C; add 300g N-methyldiethanolamine, react at 60°C for 4h, then lower the temperature to 40°C; add glacial acetic acid to adjust the pH value to 6, and then add 10kg parts by weight Dilute with acetone, then add 10 kg of deionized water for high-speed emulsification, and vacuum remove the acetone solvent to obtain a polyether polyurethane emulsion.

Example 2-1.

Dehydrate 4kg of polyoxyethylene diol under vacuum at 120°C for 2h, then lower the temperature to 70°C; add 1.5kg of toluene diisocyanate and 50g of stannous octoate under nitrogen protection, react at 85°C for 2h, then Lower the temperature to 40°C; add 600g of N-methyldiethanolamine, react at 65°C for 2 hours, then lower the temperature to 50°C; add glacial acetic acid to adjust the pH to 7, and then add 2kg of acetone to dilute , and then add 8kg deionized water in parts by weight to carry out high-speed emulsification, and vacuum remove the acetone solvent to obtain a polyether polyurethane emulsion.

Example 3-1.

Dehydrate 3.5kg of polyoxyethylene diol under vacuum at 115°C for 1.5h, then lower the temperature to 60°C; add 1.2kg of toluene diisocyanate and 5g of stannous octoate under nitrogen protection, and react at 80°C for 2.5 h, then lower the temperature to 35°C; add 400g N-methyldiethanolamine, react at 62°C for 3h, then lower the temperature to 45°C; add glacial acetic acid to adjust the pH value to 5, and then add 5kg parts by weight Dilute with acetone, then add 9 kg of deionized water in parts by weight for high-speed emulsification, and vacuum remove the acetone solvent to obtain a polyether polyurethane emulsion.

Example 4-1.

Dehydrate 3.2kg of polyoxyethylene diol under vacuum at 110°C for 2 hours, then lower the temperature to 65°C; add 1.1kg of toluene diisocyanate and 10g of dibutyltin dilaurate under nitrogen protection, and set the temperature at 82°C 2.5h at lower temperature, then lower the temperature to 32°C; add 500g N-methyldiethanolamine, react at 63°C for 2.5h, then lower the temperature to 42°C; add glacial acetic acid to adjust the pH value to 6.5, and then add parts by weight 8 kg of acetone was used for dilution, and then 10 kg of deionized water was added for high-speed emulsification, and the acetone solvent was vacuumed to obtain a polyether polyurethane emulsion.

The specific examples of the method for preparing the finishing agent solution are as follows (the model specification of polyvinylpyrrolidone in the following examples is PVP-K ₁₅ or PVP-K ₃₀ ):

Example 1-2.

Add 100g of hydroxyethyl cellulose to 2kg of 2.0M sodium hydroxide solution and stir to dissolve at room temperature; add 500g of glycidyltrimethylammonium chloride, stir evenly, heat up to 80°C, and react for 10h; Regulate the pH value of reaction system to 6 with hydrochloric acid, obtain solid product after filtering; After solid product is washed, vacuum-dried, obtain powdery hydroxyethyl cellulose quaternary ammonium salt; Get 100g hydroxyethyl cellulose quaternary ammonium salt and 2kg poly Vinylpyrrolidone was added into 10 kg of deionized water to dissolve, and the finishing agent solution was obtained after stirring evenly.

Example 2-2.

Add 300g of hydroxyethyl cellulose to 4kg of 1.0M sodium hydroxide solution and stir to dissolve at room temperature; add 1kg of glycidyltrimethylammonium chloride, stir evenly, heat up to 85°C, and react for 5h; Regulate the pH value of reaction system to 7 with hydrochloric acid, obtain solid product after filtering; After solid product is washed, vacuum-dried, obtain powdery hydroxyethyl cellulose quaternary ammonium salt; Get 500g hydroxyethyl cellulose quaternary ammonium salt and 1kg poly Vinylpyrrolidone was added into 10 kg of deionized water to dissolve, and the finishing agent solution was obtained after stirring evenly.

Example 3-2.

Add 200g of hydroxyethyl cellulose to 3kg of 1.5M sodium hydroxide solution and stir to dissolve at room temperature; add 700g of glycidyltrimethylammonium chloride, stir evenly, then raise the temperature to 82°C, and react for 7h; Hydrochloric acid regulates the pH value of reaction system to 6.5, obtains solid product after filtering; After solid product is washed, vacuum-dried, obtain powdery hydroxyethyl cellulose quaternary ammonium salt; Get 300g hydroxyethyl cellulose quaternary ammonium salt and 1.5kg The polyvinylpyrrolidone was added into 10kg of deionized water to dissolve, and the finishing agent solution was obtained after stirring evenly.

Example 4-2.

Add 250g of hydroxyethyl cellulose to 3.5kg of 1.2M sodium hydroxide solution and stir to dissolve at room temperature; add 800g of glycidyltrimethylammonium chloride, stir evenly, heat up to 84°C, and react for 9 hours; Regulate the pH value of reaction system to 6.5 with hydrochloric acid, obtain solid product after filtering; After solid product is washed, vacuum-dried, obtain powdery hydroxyethyl cellulose quaternary ammonium salt; Get 400g hydroxyethyl cellulose quaternary ammonium salt and 1.2 Add kg of polyvinylpyrrolidone to 10 kg of deionized water to dissolve, stir evenly to obtain a finishing agent solution.

Example I.

Take the polyether polyurethane emulsion prepared in any one of Examples 1-1 to 4-1, and the finishing agent solution prepared in any one of Examples 1-2 to 4-2 in a weight ratio of 20:1. Mix evenly to obtain a cationic polyether polyurethane emulsion leather finishing agent with good comprehensive performance and sanitation and sterilization.

Example II.

Take the polyether polyurethane emulsion prepared in any one of Examples 1-1 to 4-1, and the finishing agent solution prepared in any one of Examples 1-2 to 4-2 in a weight ratio of 15:1. Mix evenly to obtain a cationic polyether polyurethane emulsion leather finishing agent with good comprehensive performance and sanitation and sterilization.

Example III.

Take the polyether polyurethane emulsion prepared in any one of Examples 1-1 to 4-1, and the finishing agent solution prepared in any one of Examples 1-2 to 4-2 in a weight ratio of 12:1. Mix evenly to obtain a cationic polyether polyurethane emulsion leather finishing agent with good comprehensive performance and sanitation and sterilization.

Embodiment IV.

Take the polyether polyurethane emulsion prepared in any one of Examples 1-1 to 4-1, and the finishing agent solution prepared in any one of Examples 1-2 to 4-2 in a weight ratio of 10:1. Mix evenly to obtain a cationic polyether polyurethane emulsion leather finishing agent with good comprehensive performance and sanitation and sterilization.

Claims (2)

1. the preparation method of an EU modifying casein emulsion leather, it is characterized in that the method prepares at first respectively EU emulsion and finish solution, then EU emulsion and finish solution is even by weight 100:5～10 mechanical mixture, namely get and have good combination property, and have the cation polyether type polyurethane modifying casein emulsion leather of sanitary disinfecting;

The preparation method of described EU emulsion is:

Be the polyoxyethylene glycol of 30～40 parts 1～2h that dewaters under the vacuum condition of 110～120 ℃ with parts by weight, then cool the temperature to 50～70 ℃; Be in the polyoxyethylene glycol after 10～15 parts of toluene di-isocyanate(TDI)s, 0.01～0.5 part of catalyst add dehydration with parts by weight under nitrogen protection, react 2～3h under 75～85 ℃, then cool the temperature to 30～40 ℃; Adding parts by weight is 3～6 parts of N methyldiethanol amines, reacts 2～4h under 60～65 ℃, then cools the temperature to 40～50 ℃; Add glacial acetic acid to regulate pH value to 5～7, then adding parts by weight is that 20～100 parts of acetone dilute, then to add parts by weight be that 80～100 parts of deionized waters carry out emulsify at a high speed, and vacuum obtains the EU emulsion after extracting acetone solvent;

The preparation method of described finish solution is:

With parts by weight be the hydroxyethylcellulose of 1～3 part to join parts by weight be that 20～40 parts, concentration are in the sodium hydroxide solution of 1.0～2.0M, stirring and dissolving under normal temperature; Adding parts by weight is the epoxypropyltrimethylchloride chloride of 5～10 parts, is warming up to 80～85 ℃ after stirring, reaction 5～10h; With the pH value to 6 of hydrochloric acid conditioned reaction system～7, obtain solid product after filtering; After solid product washing, vacuumize, obtain Powdered hydroxyethylcellulose quaternary ammonium salt; Getting parts by weight and be the hydroxyethylcellulose quaternary ammonium salt of 1～5 part and 10～20 parts of polyvinylpyrrolidones, to join parts by weight be to dissolve in 100 parts of deionized waters, namely gets finish solution after stirring.

2. the preparation method of a kind of EU modifying casein emulsion leather as claimed in claim 1, it is characterized in that: described catalyst is dibutyl tin dilaurate or stannous octoate.