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Self-emulsification is an important production method for waterborne polyurethane, which allows the polyurethane molecules to have hydrophilic groups. Therefore, no additional emulsifier or vigorous agitation is required during the emulsification process. This method has the advantage of producing dispersions with small particle size, narrow distribution, and stable storage. Moreover, the mechanical properties and other application performance of the formed film are excellent. In this process, introducing appropriate hydrophilic groups into the polyurethane molecule structure and well dispersing them in water is crucial for preparing waterborne polyurethane dispersions. Hydrophilic groups can be introduced into the polyurethane molecular structure through raw materials such as polyols or chain extenders during the preparation process. Generally, hydrophilic group-containing chain extenders are used to introduce these groups into the hard segments. At present, most of the research on anionic waterborne polyurethane dispersions in China focuses on introducing hydrophilic ionic groups into the hard segments through this method. However, this may affect the regularity of the hard segments and reduce their crystallinity. Recently, someone has attempted to synthesize a carboxylic-group-containing polycaprolactone as a soft segment to prepare anionic polyurethane emulsion. According to the types of hydrophilic groups in the molecular structure, self-emulsifying waterborne polyurethanes can be classified into cationic, anionic, amphoteric, and nonionic types. Cationic polyurethanes are prepared by using V-alkyl diol chain extenders in prepolymer solutions to introduce tertiary amino groups, followed by quaternization or acid neutralization to achieve self-emulsification. Anionic types use 2,2'-dimethylol propionic acid (DMPA), diamino alkyl iodide, etc. as chain extenders to introduce iodo or carboxyl groups, and then triethylamine or other compounds for neutralization and emulsification. Nonionic types can be obtained by introducing hydroxyl, ether, hydroxymethyl, etc. nonionic groups, especially polyethylene oxide segments, into the polyurethane backbone. Hydrophilic group introduction methods also include hydrophilic monomer chain extension, polymer reaction grafting, and directly introducing hydrophilic monomers into macromolecular polymer polyols. Among them, hydrophilic monomer chain extension is simple and widely applicable and is currently the main method for preparing waterborne polyurethanes. Directly introducing hydrophilic groups into polyether or polyester polyol molecules is a commonly used method in industrial production abroad and has high application value.

Water-based polyurethane resin polyurethane dispersion preparation method. Preparation methods for water-based polyurethan dispersion mainly include: 1. Solvent method: first mix polyurethan and solvents, and then stir to obtain a homogeneous dispersion. Finally, by evaporating the solvent, a water-based polyamide resin dispersion is formed. 2. Emulsion method: first mix water-based polyol and emulsifier, and then stir and disperse uniformly. Finally, by heating, cooling, and vacuum dehydration, a stable emulsion is formed. 3. Preparation method of direct dispersion: first mix prepolymer and water, and then heat to disperse uniformly through high-speed stirring. Finally, by freezing drying, a water-soluble polyurethane dispersion with fine particles is formed. 4. Microcapsule method: first wrap the reaction-generated polymer in a microcapsule wall, and then dry and grind it into a microparticle form of water-solubilized polyurethane dispersions. 5 Self-emulsion method: introduce hydrophilic groups into the polyurethane to self-emulsify in water, forming water-solubile polyurethane powders. The above various methods can be selected and optimized according to practical needs to obtain excellent performance water-based polyether dispersions.

Anionic aliphatic polyurethane resins are a type of polymer material that is commonly used in various industrial applications such as coatings, adhesives, and inks. These resins are made by reacting isocyanate groups with hydroxyl or carboxyl groups in a polyol prepolymer, followed by emulsification and cross-linking with anionic surfactants. One of the key characteristics of anionic aliphatic polyurethane resins is their high chemical resistance. They are highly resistant to water, solvents, and many common chemicals, making them ideal for use in harsh environments. Additionally, they offer excellent adhesion properties and are compatible with a wide range of substrates, including metals, wood, and plastics. Anionic aliphatic polyurethane resins also have good mechanical properties, such as flexibility, toughness, and impact resistance. They can be formulated to provide specific properties, such as high-temperature resistance, UV resistance, and waterproofing, depending on the specific application requirements. In addition, anionic aliphatic polyurethane resins are typically low odor and low VOC (volatile organic compounds) compared to other types of resins. This makes them an attractive option for manufacturers who are looking to minimize the environmental impact of their products. Overall, anionic aliphatic polyurethane resins offer a combination of chemical resistance, adhesion, mechanical properties, and environmental friendliness that make them a popular choice for a wide range of industrial applications.

Polyurethane (polyurethanes, abbreviated PU) is a kind of polymer with -NHCOO-repeat structural unit as the main chain. Isocyanate (monomer) is polymerized with a hydroxyl compound.Due to the strong polarity of the carbamate group, insoluble in non-polar groups, with good oil resistance, toughness, wear resistance, aging resistance and adhesion. Materials suitable for a wide temperature range (-50 -- 1500℃) can be prepared with different raw materials, including elastomer, thermoplastic resin and thermosetting resin. It is not resistant to hydrolysis or alkaline medium at high temperature. Adding polyurethane resin to the ink can improve the wettability of the ink to the pigment, and the film is good, the ink film is fast and wear-resistant, and it is used in the manufacturing of offset printing and water-based ink, but the price is higher. The polyurethane resin used for printing ink is generally made of polyester/polyether polyol and isocyanate reaction, molecular weight of about 20,000 ~ 40,000. Its solvent mainly to benzene, ketone, ester solvent as the main solvent. In the process of research and development according to the ink factory and printing plant environmental protection needs, using ketone ester solvent or alcohol ester solvent to prepare the corresponding benzene free ink resin. The characteristics of polyurethane resin for printing ink are as follows: ①Excellent yellowing resistance. The polyurethane resin for printing ink is synthesized by aliphatic polyester and aliphatic isocyanate as the main raw materials in the process of preparation. Compared with aromatic polyurethane, it has excellent optical stability, and the film has excellent yellow resistance. ②Excellent adhesion fastness to film substrates. Ink with polyurethane resin molecular chain segment contains carbamate, urea formate, ester bond, ether bond and other polar groups, and a variety of polar substrates PET, PA and other plastic surface polar groups to form hydrogen bonds, and then the formation of a certain connection strength of the joint. The polyurethane resin made of ink, printing on the surface of polar plastic substrate has good adhesion fastness. ③Good affinity and wettability with pigments/dyes. Polyurethane resin for printing ink is generally prepared by polyester or polyether polyols, aliphatic diisocyanate and diamine/diol chain extender. Due to the introduction of urea bond in PU resin, polyurethane monourea resin (PUU) is formed, which makes it have good dispersion wettability for pigments. ④Good resin compatibility. Ink with polyurethane resin and aldehyde-ketone resin, chloro-vinegar resin has a good compatibility, according to the actual situation in their own process formula appropriate to add, in order to improve the comprehensive performance of ink. ⑤Excellent film forming properties. Ink polyurethane resin and other fields of polyurethane resin used in the structure is different, the traditional polyurethane is mainly polyester polyol/polyethe...

Water based polyurethane resin, also known as water based polyurethane dispersion, water-based PU dispersion or water-based polyurethane emulsion, is a new type of polyurethane system in which water replaces organic solvent as the dispersion medium.Water based polyurethane uses water as solvent, which has the advantages of no pollution, safe and reliable, good mechanical properties, good compatibility and easy modification. Let's take a closer look at the classification of water based polyurethane emulsion. Polyurethane emulsions can be subdivided into polyurethane emulsions and urethane - urea emulsions. The latter refers to the emulsions formed by polyurethane prepolymer dispersing in water through water or diamine chain expansion, essentially producing urethane - urea, but due to the preparation by prepolymer dispersion method is more common, traditionally known as polyurethane emulsions in the majority. According to the molecular structure can be divided into linear molecular polyurethane emulsion (thermoplastic) and crosslinked polyurethane emulsion (thermosetting).The crosslinker type can be subdivided into internal cross - link and diplomatic - link type.The inner - coated polyurethane emulsion is a stable one - component system.Crosslinking is a two-component system in which the crosslinking agent is added to the emulsion and can react with the groups in the polyurethane molecular chain For any requirements on water based or solvent based polyurethane resin/dispersion/emulsion and isocyanate crosslinker ,feel free to contact us !

Waterborne acrylic resin emulsion was prepared by using butyl acrylate, methyl methacrylate, and methyl acrylate as monomers via emulsion polymerization. Afterwards, it was modified with waterborne polyurethane Resin to produce waterborne polyurethane-acrylic resin emulsion. Two types of water-soluble resin were used as connecting materials, which were each formulated into waterborne inks and printed on the surface of PVC plastic. The difference in lightfastness between the two types of waterborne ink connecting materials in PVC plastic surface printing was compared, and the fundamental reasons were explored from a microscopic perspective. Waterborne acrylic resin emulsion （referred to as PA emulsion） was prepared. Waterborne polyurethane-acrylic resin emulsion （referred to as PUA emulsion） was prepared by using PA emulsion, waterborne polyurethane, sodium lauryl sulfate, laboratory grade III water, a waterborne ink defoamer, ammonia water and other raw materials. The two types of waterborne inks were formulated according to the two plans in the table below, in which the waterborne ink formulated with PA emulsion as a connecting material was referred to as WPA, and the waterborne ink formulated with PUA emulsion as a connecting material was referred to as WPUA. The final pH of the waterborne ink was adjusted to between 8.0 and 9.0 using ammonia water. Basic performance tests were carried out on the two types of waterborne inks formulated with different connecting materials, exploring the differences in performance between the two types of waterborne inks in terms of fineness, viscosity, initial drying time, color strength, pH value, adhesion and water resistance. The test results are shown in the figure below. From the figure, it can be seen that the fineness of WPA is between 0.2 and 5.0 μm, viscosity is between 10 and 30s, initial drying time is between 15 and 17mm, color strength is between 45% and 60%, pH value is between 8.0 and 9.0, adhesion is between 70% and 90%, and water resistance is level 4. The fineness, viscosity, initial drying time, color strength, and pH value of WPUA are the same as those of WPA. However, the adhesion of WPUA is between 75% and 95%, and the water resistance is level 5, which is better than that of WPA. This indicates that using WPUA has stronger cohesion and better water resistance when printing on the surface of PVC plastic. The fundamental reason mainly depends on the fact that the molecular chain of waterborne polyurethane contains hydrophilic groups of aminoethyl methacrylate (—NH—COO—), which not only has strong affinity with water, but also captures the hydrogen ions on the surface of PVC plastic molecules through these large molecular groups, making the two types of molecules firmly aggregate. Therefore, using waterborne polyurethane-modified connecting material after acrylic resin will significantly improve the adhesion and water resistance performance.

Polyurethane resin has found extensive applications in the preparation of gravure printing inks for plastic films, particularly for treated polypropylene (opp), polyester (pet), nylon (ny) and other plastic films. PU resin is suitable for plastic composite materials and photographic gravure printing inks. It exhibits excellent bonding and boiling water resistance when used for packaging that requires steaming, demonstrating its robust heat resistance. The primary advantages of using polyurethane resin in the production of gravure printing inks for plastic films are as follows: Excellent Yellowing Resistance: The resin, which is primarily synthesized from aliphatic polyesters and aliphatic isocyanates, exhibits superior optical stability compared to aromatic polyurethanes. This translates to a film with excellent resistance to yellowing, ensuring consistent color quality over time. Strong Adhesion to Plastic Substrates: The molecular structure of the polyurethane resin contains various functional groups such as urethane, urea, ester, and ether bonds. These groups interact with the surface of PET, PA and other plastic substrates, forming hydrogen bonds and ensuring strong adhesion between the ink and the substrate. High Performance under Printing Conditions: The polyurethane resin exhibits excellent adaptability to printing processes, making it less prone to issues such as smudging or streaking that can affect print quality. It provides a robust and consistent printed image that maintains its quality even under challenging conditions. Environmental Friendliness: Polyurethane resin inks produce fewer volatile organic compounds (VOCs) compared to traditional solvent-based inks, reducing environmental impact while also complying with evolving environmental regulations. Wide Application Range: Polyurethane inks are compatible with a variety of printing methods and are suitable for printing on various plastic substrates such as PET, BOPP, and NY. This versatility enables manufacturers to switch between substrates or printing methods without significant changes to the ink formula. Cost-Effective: While the initial cost of polyurethane inks may be higher than that of some traditional inks, their durability and performance characteristics often lead to cost savings in the long run by reducing the frequency of ink changes and enhancing overall print quality. In conclusion, polyurethane resin has unique properties, including its excellent yellowing resistance, strong adhesion to plastic substrates, high performance under printing conditions, environmental friendliness, wide application range, and cost-effectiveness, make it an excellent choice for the preparation of gravure printing inks used in the production of plastic films. Its adaptability to evolving environmental regulations and the consistent quality it provides to printed images make it a valuable addition to the toolbox of any manufacturer printing on plastic substrates.

Polyurethane resin is widely used in the production of inks and coatings due to its unique properties, such as good adhesion, toughness, and durability. Here are some examples of how polyurethane resins are used in inks and coatings: 1. Polyurethane resin-based inks: Polyurethane resin-based inks are used in a variety of applications, including printing, packaging, and industrial coating. They offer excellent adhesion, toughness, and resistance to chemicals and heat, making them suitable for use in demanding applications. 2. Polyurethane resin-based coatings: Polyurethane resin-based coatings are used in a variety of applications, including automotive, aviation, and architectural coatings. They offer excellent adhesion, toughness, and resistance to chemicals and heat, making them suitable for use in demanding applications. 3. Polyurethane resin-based adhesives: Polyurethane resin-based adhesives are used in a variety of applications, including packaging, construction, and automotive. They offer excellent adhesion, toughness, and resistance to chemicals and heat, making them suitable for use in demanding applications. Overall, polyurethane resins are a versatile material that can be used in a variety of inks and coatings applications due to their unique properties, including good adhesion, toughness, and durability.