Polyurethane waterproof coatings arr_right_inav

One-Component Polyurethane Waterproof Coating

Description Specifications Scope of Application FAQ Download

Description

YHPUcoat-8400 is a single-component, cold applied, moisture-cured aromatic polyurethane waterproofing membrane. It cures to form a seamless and robust waterproofing layer intended for use as the base coat under an aliphatic polyurethane/polyurea top coat (e.g., YHPUroof-8401, 8531, 8532 and 8733), or under a separate wearing course of concrete, for heavy pedestrian and/or vehicular traffic applications.

Specifications

CHARACTERISTICS AND PACKAGING

Item	Data
Appearance	Viscous Liquid
Viscosity/cp	9000±3000
Color	Grey
Density/kg/L	1.05-1.15
Solid Content by Weight	85-87 %
Pot life/h	2
Packing Size	20 kg per metal drum

PROPERTIES

Description	Test Methods	Typical Values
VOC / (g/L)	ASTM D2369	≈190
Tensile Strength / MPa	ASTM D412	≥11
Elongation at Break / %	ASTM D412	≥350
Tear Strength / N/mm	ASTM D624	≥35
Pull-off Adhesion to Concrete / MPa	ASTM D7234	≥2.5
Shore A Hardness	ASTM D2240	≈70
Water Penetration Test (5 bar, 3 days)	DIN 1048-5	No Penetration
Low Temperature Flexure (-35℃)	ASTM D522	No Cracks
Set-to-Touch Time / h	ASTM D1640	≈2

Note: The above data were tested under standard conditions (temperature 23 °C ± 2 °C, relative humidity 50% ± 10%).

APPLICATION INSTRUCTIONS

Items	Description
Consumption*	1.25-1.40 kg / m2 for 1mm dry film
Coverage	10-11 m2/set (20kg) at 1.5mm dry film thickness
Recommended thickness	1.2-1.5 mm by 2 coats 1.0-1.2 kg / m2 / coat at 0.7-0.8 mm dry film thickness
Ambient air temperature	5 °C min / +40 °C max
Relative air humidity	<85%
Substrate temperature	5 °C min. / +40 °C max. ≥ 3 °C above dew point, beware of condensation

*Material consumption depends on the porosity and texture of the substrate.

ADVANTAGES

· Cold-applied and moisture-cured; no mixing, heating, or flame required.

· Excellent crack-bridging properties and flexibility, even at low temperatures.

· Resistant to water, deicing salts, diluted acids, and alkalis.

· Good adhesion to most substrates.

· Does not crystallize at low temperatures.

Scope of Application

Recommended as a waterproof base coat beneath cementitious or concrete protective layers for airports, railway stations, parking garages, and arenas. It can also be combined with high-performance aliphatic polyurethane/polyurea topcoats for stadiums and other outdoor waterproofing projects exposed to heavy pedestrian and, such as YHPUroof-8401, YHPUroof-8531, YHPUroof-8532, and YHPUroof-8733, for balconies, stadiums, and other outdoor waterproof projects with heavy pedestrian traffic.

FAQ

Q1: What is the advantage for liquid applied membrane (coating)?

It is suitable for various type of structures and substrates, it can form seamless membrane without joint (seams and joints are the most vulnerable to leakage), and is beneficial for complex structures. The liquid coatings has various functions, sucha as flexible, high strength, excellent abrasion resistance, high load bearing property, and breathable capability, etc.
Q2: What is the difference between one-component polyurethane and two-component polyurethane?

Firstly, the isocyanate group in one - component polyurethane reacts with moisture to form a membrane. Two - component polyurethane has two parts: one part is isocyanate, and the other part is polyol or polyamine, and these two components react with each other to form a membrane. Secondly, due to the difference in the reaction mechanism, the sensitivity to atmospheric conditions is also different. For one - component PU, high moisture and temperature can increase the reaction speed. In contrast, two - component PU has better storage stability, and its reaction speed is hardly affected by moisture.
Q3: Why should the polyurethane coating be used up as soon as possible after opening the container?

Because moisture in the air can enter the container and cure the remaining coating inside.
Q4: What are the differences between sag - resistant PU and levelling PU?

Sag-resistant PU has rheological properties. Rheology is the study of the behavior of materials during "flow" or "deformation" processes. There are several common "rheological behaviors" from the molecular level: 1) Shear thinning,This is the most common type of non - Newtonian behavior. It means that when you apply a shear force to the material (such as stirring, scraping, extruding), the viscosity of the material will decrease. ; 2) Thixotropy: Thixotropy is an "upgraded version" of shear thinning, with an additional dimension: time. Its definition is: During the continuous shearing process, the viscosity of the material will gradually decrease with time; after stopping shearing, it can gradually recover the original viscosity. This ability of "temporarily becoming thin + reversibly recovering" is exactly thixotropy. Materials with good thixotropy can "flow smoothly" during construction, but can quickly recover viscosity to avoid "collapse" and "sagging". For the sag-resistant coating, it is easy to scrape and apply during construction, and does not sag when left standing, ensuring the bonding thickness.
Q5: Can polyurethane coating be used for indoor construction

Yes, the non-solvent polyurethane and water-based polyurethane can be used for indoor waterproofing applications. Non-solvent polyurethane is a high-solids, ultra-low VOC coating, especially suitable for areas with poor ventilation and sensitivity to odors or volatiles.