Five factors to consider when selecting waterborne polyurethane additives
The addition of additives to waterborne polyurethane resin is to improve the production process and product performance, such as giving waterborne polyurethane new, special properties, extending the service life of waterborne polyurethane, expanding the scope of application, improving the processing efficiency and accelerating the reaction process.
There are many kinds of waterborne polyurethane additives, and the scope of use is very large, but the selection method of additives has certain rules.
Selection of waterborne polyurethane additives need to consider factors
1. Compatibility of additives and products
This is the first thing to consider in the selection of additives. In principle, it is required that the additives are compatible with the material (similar structure) and stable (no new substances generated) in the material, otherwise it is difficult to play the role of additives.
2. Durability of additives
Added to the material in the additives must be in a long time to maintain the original performance of the additives unchanged, and additives in the use of conditions, the ability to maintain the original performance is called the durability of the additives. There are three ways for additives to lose their original properties: volatilization (molecular weight), extraction (solubility of different media), migration (solubility of different polymers). The additives should have water resistance, oil resistance and solvent resistance at the same time.
3. Adaptability of additives to processing conditions
In the processing of materials, additives should not change its original properties and processing equipment and construction tools do not produce corrosion.
4. Adaptability of additives to the use of products
Additives to meet the special requirements of the material in the process of use, especially the toxicity of additives.
5. Synergistic and antagonistic effects of additives in cooperation
In order to get a better use of the effect, the use of additives are mostly used in compounding. The use of compounding, there are two kinds of cases: one is the use of compounding to achieve good results, and the other is for a variety of purposes, such as both leveling and defoaming, both light and antistatic. This should be noted: in the same material will produce synergistic effect between the additives (total effect is greater than the sum of the effect of separate use), sum effect (total effect is equal to the sum of the effect of separate use) and the effect of confrontation (the total effect is less than the sum of the effect of separate use), so it is best to produce synergistic effect when compounding to avoid the effect of confrontation.
