How to choose additives in waterborne polyurethane? There are many kinds of water-based polyurethane auxiliaries, and the application range is wide, but the methods of auxiliaries are correspondingly regular. The compatibility of additives and products is also the first factor to be considered in the selection of additives. Under normal circumstances, the auxiliary and the material are required to be compatible (similar in structure) and stable (no new substance generation) in the material, otherwise it is difficult to play the role of the auxiliary. The additive in the additive material must maintain the original performance of the additive for a long time without changing, and the additive in the application environment, the ability to maintain the original performance is called the durability of the additive. There are three ways for auxiliaries to lose their original properties: volatilization (molecular weight), extraction (solubility of different media), and migration (solubility of different polymers). At the same time, the additive should have water resistance, oil resistance and solvent resistance. In the processing process of materials, additives can not change the original performance and will not have a corrosive effect on the production and processing of machines and construction supplies. The additive needs to meet the special requirements of the material in the use process, especially the toxicity of the additive. In order to get better results, the application of additives is mostly mixed. When choosing a combination, there are two situations: one is the combination application to obtain good results, and the other is for a variety of purposes, such as not only leveling but also defoaming, not only to add light but also antistatic. This is to consider: in the same material will produce synergies between the additives (total effect is greater than the sum of the effect of single use), the addition effect (total effect is equal to the sum of the effect of single use) and the antagonistic effect (total effect is less than the sum of the effect of single use), so the best time to produce synergies, to avoid the antagonistic effect. In the production process of water-based polyurethane to add a certain type of additives, it is necessary to pay attention to its role in the various stages of storage, construction, application, and consider and evaluate its role and impact in the next section. For example, when the water-based polyurethane paint is operated with wetting and dispersing agents, it plays a certain role in storage and construction, and it is also good for the color of the paint film. There is usually a dominant effect, and at the same time cause a series of simultaneous positive effects, such as the use of silicon dioxide, there is a extinction effect, and the absorption of water, surface anti-adhesion and other positive effects. In addition, in the use of a certain agent may have a negative effect, such as the addition of si...

There are four common waterborne polyurethane thickeners: ①Inorganic thickeners, such as flake silicates, fumed silica, etc.; ②Natural organic thickeners, such as cellulose ethers; ③Synthetic organic thickeners, such as polyacrylates, polyvinylpyrrolidone; ④associative thickener. This paper mainly introduces the associated emulsion thickener. Associative emulsion thickeners are non-ionic synthetic water-soluble polymers, alkali-soluble emulsions and other thickeners with hydrophobic groups. Hydrophobic groups are generally composed of alkyl groups with a carbon atom number of 12 to 22. In view of the association between hydrophobic groups to form a network and thicken, they are called associated thickeners. By adjusting the relative molecular mass of the hydrophobic group or the polymer main chain to thicke, from the inclined flow to the pseudoplastic flow transformation, from the properties of some polymer surfactants found that this has a strong thickening, such rheological characteristics can be freely designed. The advantages of association thickeners used in waterborne polyurethanes are: ①High thickening effect; ②The flow is closer to the cow inclination fluid; ③The viscosity of low shear rate is relatively low, and the flattening property is good; ④The viscosity of high shear rate is better and the film forming property is good; ⑤It is not easy to form a spatter effect ⑥It will not be degraded by microorganisms. The disadvantage is that the thickening effect is more sensitive to the formulation of water-based coatings, including the size of latex particles, emulsifiers, additives, and cosolvent types. The association type thickener has been successfully applied in waterborne polyurethane system for several years, and there are industrial products in China. This association type thickener is dissolved in water/organic solvent (such as propylene glycol) to form polymer solution. Among them, the role of organic solvents is to reduce the viscosity of concentrated solutions and improve operability. However, organic solvents also become part of the VOC in the paint. The new development direction is to make the association thickener solvent-free. The role of the solvent is replaced by a polymeric surfactant that acts as a solubilizer for polymers in water.

Laminating glue is currently a kind of strong glue widely used in the market, so what is the application processing process of laminating glue? The application processing technology of laminating glue is as follows: 1, the composite method is dry composite, that is, the coating machine should use a dry composite machine with curing furnace and composite roller heating. 2, curing furnace ambient temperature of about 60-95 ℃. The ambient temperature of the compound working pressure roller is about 40-70 ℃, and the compound working pressure is about 8-20kg. 3, it is best under permitted conditions, the strong glue is baked to 7-9 dry is appropriate, in such an environment composite products color is relatively high, rapid speed. In such a compound environment, compound working pressure rollers. 4, for gold printing silver products or printing ink and gold and silver cardboard that are very easy to discolor reaction, the strong glue must be thoroughly dried. The ambient temperature should be reduced to less than 50℃ to prevent the occurrence of large bubbles in composite products; The working pressure should be slightly reduced, and the most appropriate is that the strong glue is not squeezed. 5, in the selection of strong glue is completely dried processing process, the composite working pressure roller temperature in the case of not burning the film the higher the better, the greater the working pressure the better. Common faults and treatment methods of water-based dry film adhesive (laminating adhesive) Transport storage temperature shall not be lower than 5 degrees, pay attention to anti-freezing and sunscreen. The machine must be cleaned before use; Products generally can not be mixed with other glues; When the machine stops, clean the rubber roller, scraping plate and groove in time; All BOPP films must be corona qualified; It is recommended to make a small sample before laminating gold and silver ink prints to confirm no color difference and bonding strength, and must wait until the glue is completely dry before pressing; If the composite product has the following conditions or is processed after coating, a sample should be tested before mass production; 1.Gold and silver cardstock; 2. embossing; 3.concave and convex; 4.Paper hanging; 5.Printed matter with thick ink layer or large dry oil; Sinograce Chemical is the production of paper film composite water-based Lamination Adhesive suppliers and technical guidance, welcome to inquire.

The difference between water-based paint and paint: Compared with paint, water-based paint, its wear resistance, and aging resistance have been significantly improved, compared with traditional paint, water-based paint is more affordable, more easily used by people, and less harmful. Water-based paint, water as diluent, with wear-resistant, aging resistance, easy to use and other characteristics, and harmless to the human body, does not pollute the environment, can be used in: metal, glass and other materials. Advantages of water-based paint 1.Use water as solvent. Save resources; Eliminate security risks; Reduce air pollution; Improve working conditions. 2.can be directly constructed; Good surface adaptability, strong adhesion. 3.Tools can be washed to reduce the consumption of cleaning agent and reduce the damage to construction personnel. 4.Tools can be washed to reduce the consumption of cleaning agent and reduce the damage to construction personnel. Water paint defect 1, the construction requirements are high, because the surface tension is large, easy to make the film shrinkage; 2, the stability is poor, the coating film produces pitting. No defects in tube wall. 3, high corrosion, high equipment cost. Stainless steel tube should be used if pitting occurs in the coating film. 4, the construction requirements are strict, increasing energy consumption. 5, evaporation potential heat is large, need 180℃ baking; It takes a long time to dry. 6, baking produces soot, the surface affects the appearance. 7, water resistance, poor stability. Further information: Water-based paint, water-based anti-rust paint, water-based steel paint, water-based floor paint, water-based wood Varnish, wood wax oil It is harmless to the human body, does not pollute the environment, the paint film is full, crystal clear, good flexibility and has the characteristics of water resistance, wear resistance, aging resistance, yellowing resistance, drying fast, easy to use and so on.