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Many of our friends make water-based light anti-corrosive paint. They will use some acrylic lotion. They always hope that the surface will be dry and the actual work will be done as soon as possible. How to achieve the goal of quick drying? Usually, I think there are several aspects to consider.

Firstly, we need to choose the appropriate TG

In terms of the glass transition temperature of this acrylic lotion, generally speaking, the higher the volume of the lotion, the higher the glass transition temperature, and the faster the drying will be. But it’s not necessarily the higher the better, because if the TG is too high, the minimum film-forming temperature will also be high. More film-forming aids need to be added.

A high amount of film-forming additives can also affect the drying speed. Film forming aids volatilize slowly. We reduce the amount of film forming aids TG paste to reduce the amount of film forming aids. The film of lotion with poor film forming may also crack. The final performance is also not good.

Second, the core shell structure of the lotion is chosen. The core has a high TG. The volume of the shell is low, which can ensure that the minimum film forming temperature of the lotion is not high under the condition of high TG and fast drying. There is no need for too many film-forming agents, and good film-forming properties can be guaranteed.

Third, the monomer used for lotion synthesis will also affect the drying speed. The more monomers with clear water, the faster the drying. For example, pure acrylic lotion dries faster than benzene lotion. After the hydrophobic surface dries, it will seal the water inside, making it difficult to come out. Hydrophilic monomers provide channels for water release.

Fourth, it is the choice of film forming aids. The best film forming aid for acrylic lotion is alcohol ester 12, but its molecular weight is relatively high, and its volatilization is very slow, which can be completed in a month or two. It takes a long time for it to evaporate in the paint film. It is recommended to use DPNB for industrial paint, combined with DPM. DPNB itself also has a good film-forming effect. That evaporates much faster than alcohol esters. Paired with fast drying DPM, a perfect balance between film-forming effect and drying speed can be achieved.

In light anti-corrosion coatings, many people also like to use ethylene glycol butyl ether as a film-forming agent, such as BCS. BCS evaporates relatively quickly, but its film-forming effect is relatively poor. It can be used in small quantities and cannot be used as the main film-forming aid.

Fifth, add a quick drying solvent. Adding some fast drying solvents such as ethanol to the formula can form this azeotrope with water, making it easier for water to evaporate. Some customers may also use methanol, which can improve the drying speed more effectively. However, methanol is quite toxic, so please pay attention to safety, especially its harm to the eyes.

Sixth, the amount of fillers added can also affect the drying speed, and adding more fillers can reduce the resin content. There are gaps between the fillers, which can provide a channel for water vapor release and significantly accelerate drying. Adding too much filler will decrease the gloss. We can also choose ultrafine materials such as ultrafine barium sulfate, also known as high gloss barium, which has less impact on gloss. In addition, adding a suitable dispersant can generally reduce viscosity, increase gloss, increase the loading capacity of pigments and fillers, and increase drying speed.

Seventh, the roughness of the substrate will affect the drying speed of the paint film. Porous and rough substrates dry faster, while porous substrates absorb water and naturally dry faster with less water. Like cement substrates, they all have this function, as well as wood and some rough substrate surfaces because they are uneven. Unevenness will also result in uneven paint film. If the paint film is not smooth, its contact surface with the air will be larger, and the evaporation will be faster. Additionally, the thickness of the film also affects the drying speed. The thinner the film thickness, the faster the moisture will run, and the drying will naturally be faster.

Some systems that require particularly fast drying can be applied with thin coating. The drying of water-based coatings is greatly affected by temperature and humidity. The higher the temperature, the faster the water evaporates. Water based coatings are not afraid of low temperatures, but rather of high humidity. During the rainy season in the south, the humidity is very high. For example, if we hang our clothes for a day, they may not even dry. Under these climatic conditions, the dryness of water-based coatings during construction will be greatly affected. Construction should be carried out in dry weather as much as possible.

Construction must be carried out in low temperature or high humidity conditions as a last resort. We need to strengthen environmental ventilation. Ventilation has a positive impact on the evaporation of water and accelerates the drying speed of the paint film.