Answer: The most common coating waterproofing materials are:
(i) Polyamide PU:
(1) Coal tar series PU.
(2) Non-paraffin series PU (carbon fiber black PU, general colored PU).
(ii) Colored acrylic rubber waterproof material made from acrylate elastomer emulsion has better UV resistance, but this type of material is more suitable for exterior walls.
(3) A water-proofing material made from vulcanized asphalt based on emulsified asphalt and synthetic emulsion resins.
(4) Waterproofing materials made from emulsified asphalt and rubber.
The materials in categories (III) and (IV) are collectively referred to as RA glues. They have poor UV resistance and are therefore not suitable for use on exposed surfaces. Furthermore, if the substrate is excessively wet before installation, bubbles, swelling, or even hydrolysis can easily occur.
(5) High-pressure spray-applied fast-curing polyurethane (curing in 10 seconds), semi-polyurethane, and fast-curing PU—These types of materials have been used in some cases since the structural surfaces of the Taiwan high-speed rail project in the past 5 years (in new luxury housing projects). However, a phenomenon of price-cutting competition has begun to emerge in the market; they have started mixing the most expensive polyurethane, the second-most expensive semi-polyurethane, and the relatively inexpensive fast-curing PU together. Even in many roof renovation projects, emphasis is placed on the ability to spray directly without digging out the material, but it often fails within less than a year… The market can be said to be entering a controversial era. (See question 28 in this book in detail.)
(6) High-pressure spray-applied fast-curing rubberized asphalt (curing in 20 seconds), this is the latest waterproof material recently invented. Although there are not many construction cases for this type of waterproof material, the author believes that among the interior walls, roofs, tree holes, swimming pools, flower beds, and water tanks of new luxury homes with an area of over 2000 square meters, it is more suitable to use this type of material, with endless potential.