High-performance environmentally friendly waterproof coating-new application of waterborne polyurethane dispersion

The industry is well-known waterproof coating is mainly polyurethane system, which is isocyanate, polyether and other polymerized by the polymerization of isocyanic acid-based pre-polymer, with catalysts, waterless fillers, solvents, etc., by mixing and other processes processing.
Compared with the thermal viscosity and brittle characteristics of acrylic resin, polyurethane resin has the characteristics of hard but not brittle, soft and non-stick, the use of resin with this characteristic prepared waterproof coating, at normal low temperature fracture elongation, fracture strength is very good, can meet the waterproofing needs of most scenes.
with the consumption upgrade, environmental protection requirements gradually increased, environmentally friendly coatings have been

. How to upgrade the common waterproof coating with a small amount of solvent to a high solid content system or solvent-free system, and how to convert to a water-based waterproof system, which has become a hot topic in the waterproof industry. Resin emulsions used in conventional water-based coatings can be roughly divided into acrylic, EVA, polyurethane, etc.
In the same waterproof coating formulation conditions, waterproof coating mechanical performance, water absorption rate, bonding strength and other performance, what are the characteristics,
please see the following explanation:
1, mechanical performance
waterproof coating mechanical performance, has been one of the most important items to characterize the good paint or not, and the resin preparation paint has the greatest impact on its mechanical performance.
Water-based polyurethane dispersion retains the soft and hard segment characteristics of the molecular chain segment of polyurethane resin, has good elasticity and strength, and the normal low temperature fracture elongation and fracture strength in waterproof coatings are also excellent:
2, alkali treatment mechanical properties
waterproof coating directly applied to the concrete substrate, will be affected by the base pan-alkali, used indoors will also be affected by alkaline cleaning agent. Excellent alkali resistance extends coating life and provides long-lasting water resistance. In contrast, water-based polyurethane waterproof coatings show excellent alkali resistance.
3, water absorption rate
absorption rate is too high, the coating after long-term immersion will dissolve, bubble, and grass-roots adhesion decreased, resulting in a decrease in waterproof capacity.
waterproof coating prepared with polyurethane and acrylic emulsion, its water absorption rate is as follows:
experimental results show that the PA coating presents a different deformation:
4, bonding strength
bonding strength characterizes the coating's adhesion to the substrate, the higher the strength, the better the adhesion, the less easy it is to fall off.
water-based polyurethane waterproof coating bonding strength is high, and there is no significant change in different substrates, expanding the application of waterproof coatings.
5, VOC
. VOC is a volatile organic compound that has a huge impact on human health. When the VOC in the room reaches a certain concentration, a short period of time people will feel headache, nausea, vomiting, fatigue, etc. , serious will appear convulsions, coma, and will hurt the human liver, kidneys, brain and nervous system, resulting in memory loss and other serious consequences. The paint used in the decoration process of home decoration is one of the main sources of interior VOC, and all countries have limited the VOC content of decoration materials such as paint.
Water-based waterproof coatings perform extremely well on VOCs:
says that under the same formula (shown below), water-based polyurethane dispersion system-ready waterproof coatings exhibit better mechanical properties, lower water absorption and higher bonding strength, and lower VOC.
for example: water-based PU waterproof coating room temperature elongation rate of 620%, fracture strength 4MPa, water absorption rate of 8%, substation bonding strength of 1.5MPa, VOC about 10g/L, can effectively cover the wall small cracks, reduce seepage, extend service life, etc., reduce the building waterproof repair rate, improve the quality of life.
Note: The PUD emulsion used in this paper is Archsol®8355
Million Hua Chemical Surface Materials Division
mainly engaged in the research and development, production and sales of environmentally friendly surface materials and new energy materials, relying on the company's upstream polyurethane and acrylic raw materials advantages, extend the industrial chain, to create a million output value of green sustainable business. Formed water-based polyurethane (PUD), water-based acrylic (PA), modified polyurethane (PUA), water-based photo-curing (UV), water-based dual-group (2K), water-based epoxy (EP), rheumorative aids (HEUR and HASE), bio-based Source Soft Bioderived Beads, Ultra absorbent resin (SAP), reverse osmosis membrane (RO), nanfiltration membrane (NF), hollow fiber (HF), adsorption resin (AR), lithium-ion battery positive material 14 major research and development technology platform, and the corresponding technical services.
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