Waterproof liquid PU membrane: The Ultimate Guide

 

While you are choosing to purchase quality waterproof liquid PU membrane, there are a few important points to know before you begin.

 

what is a waterproof liquid PU membrane?

Properties: what are the properties of this kind of waterproof liquid PU membrane? 

Application: where can a waterproof liquid PU membrane be used?

Effect of isocyanate index on properties of waterproofing coatings

What is the effect of PU film waterproof fabric?

China PU Membranes factory

PU Membranes factory

 

 

 

what is a waterproof liquid PU membrane?

 

A waterproof liquid PU membrane is a type of coating that is applied to surfaces in order to make them water resistant. This type of coating is typically made from polyurethane, which is a synthetic polymer that is known for its durability and resistance to water. The PU membrane is applied as a liquid, and then it dries and forms a bond with the surface it has been applied to. This bond helps to create a barrier between the surface and any water that may come into contact with it. This type of coating can be used on a variety of different surfaces, including concrete, metal, glass, and plastic.

 

 

 

Properties: what are the properties of this kind of waterproof liquid PU membrane? 

 

PU waterproofing membranes are made of polyurethane, which is a kind of polymer. The main component of PU is isocyanate, and the main ingredient of isocyanate is toluene diisocyanate (TDI). 

2. PU waterproofing membranes have good mechanical properties and tensile strength. They are resistant to tearing, puncturing, abrasion and impact. They also have good elongation at break.

 

3. PU waterproofing membranes are highly elastic and can be stretched up to 500% without breaking. They have excellent UV resistance and can last for more than 20 years without deteriorating.

 

 

 

Application: where can a waterproof liquid PU membrane be used?

 

Waterproofing is a critical aspect of many construction projects, and a variety of different materials and techniques are available to achieve it. One option is a liquid polyurethane (PU) membrane, which can provide an effective waterproof barrier in a wide range of situations. 

PU membranes are commonly used to waterproof roofs, basements, and other structures that are exposed to moisture. They can also be used to protect concrete surfaces from water damage. PU membranes are typically applied as a liquid coating that dries to form a durable, flexible film.

 

 

 

Effect of isocyanate index on properties of waterproofing coatings

 

With the increase of isocyanate index, the tensile strength, elongation at break, tear strength and bond strength of PU waterproof coating increased first and then decreased, while the hardness gradually increased and the water absorption gradually decreased. The main reason is that an appropriate R value can improve the comprehensive performance of PU waterproof coating.

 

When R value is appropriate (R=1.4), can increase the crosslinking density, improve the content of the hard segment, the rigidity of the coating molecular chain increases, and the polymer provides strength of the hard segment and the soft segment of toughness microphase separation, so the tensile strength, elongation at break, tear strength and bond strength are increased.

 

Mixer R is too large, the crosslink density is too big, can lead to stress concentration, caused the PU film brittle, have crack, especially under the condition of low temperature crack is more serious, excessive cross-linking will also lower the activity of molecular chain, results in the decrease of PU waterproof coating strength and elongation, hardness increased, membrane stiffness, permeability variation at the grass-roots level, the bond strength decreases.

 

When R value is too low, the surface of PU film is sticky, the hardness is low, the water absorption is high, and the PU film is not waterproof.

 

In order to observe the bonding effect between PU waterproof coating and base concrete more intuitively, the bonding tests at R=1.4 and 1.6 were carried out. When R=1.4, the bond with the base is better, and it requires a large force to tear, and the broken film also shows a large elongation performance; When R=1.6, the film and the base bond is poor, it is easy to tear.

 

 

 

What is the effect of PU film waterproof fabric?

 

PU coated Oxford cloth has advantages. PU coating, namely polyurethane coating, makes the fabric feel plump, elastic and membranous after coating. PU coated Oxford cloth is mainly used in outdoor products and military, its characteristics are mainly moisture permeability, wear resistance, wind resistance, softness. PU coating on its coating form to be divided, simply said can be divided into water-based and solvent-based polyurethane.

 

The solvent-based film has good performance, strong adhesion with fabric, high water pressure resistance, and is more suitable for waterproof and moisture permeable coating. However, the solvent type has certain toxicity and inflammability, not environmental protection, the water-based type is safe and non-toxic, which is beneficial to environmental protection, but the adhesive force with the fabric is poor, and the water pressure resistance is weaker than the solvent type.

 

The main functions of waterproof Oxford fabric are: waterproof, moisture permeable, breathable, insulation, wind proof, warm. From the production process, the technical requirements of waterproof breathable fabric are much higher than the general waterproof fabric; At the same time from the quality point of view, waterproof breathable fabric also has the functional characteristics that other waterproof fabrics do not have. Waterproof and breathable fabric not only strengthens the air tightness and water tightness of the fabric, but also its unique vapor permeability performance, which can make the water vapor inside the structure quickly discharged, avoid the structure breeding mold, and keep the human body always dry, solving the problems of air permeability and wind proof, waterproof, warm and so on. It is a new type of healthy and environmentally friendly fabric.

 

 

 

China PU Membranes factory

 

SHENGHANG is a leading PU Membrane factory in China, focusing on the manufacturer of PU membranes. We focus on producing high-quality products with complete specifications. The quality of our products has passed international certification and the price is affordable.

 

The PU Membrane factory produces a wide variety of PU membranes. These membranes are commonly used in water and wastewater treatment plants, natural gas pipelines, food processing plants, pharmaceutical, and other chemical production lines. The membrane made of PU is very durable and corrosion-resistant.

 

Polyurethane (PU) membrane is a waterproof and durable material that can be used in different applications. This material has many properties that make it attractive, such as water resistance, high strength, and low permeability.

 

 

 

PU Membranes factory

 

A membrane is a thin sheet of material that separates two liquids, gases, or other fluid substances. Membranes offer many advantages over traditional materials because they are:

 

- Durable: The membrane can be used for many years without degrading.

 

- Flexible: The membrane can be stretched or pulled without breaking.

 

- Transparent: membranes allow substances to be viewed through them.

 

- Cost-effective: Membranes are cheaper than traditional materials.

 

PU membranes are gaining popularity in water treatment applications due to their numerous advantages. These membranes are particularly useful for removing contaminants such as bacteria and heavy metals from water. They are also effective at reducing fouling and scaling and can be easily replaced if they become damaged.