Is Polyurethane Used in Container Houses?
Container houses use polyurethane materials, primarily for key functions such as thermal insulation, fire prevention, and structural bonding. Here are the specific application scenarios and their roles:
1. Core material for thermal insulation
The polyurethane foam layer is a core component of the thermal insulation system in container houses. For example, residential container houses adopt a three-layer structure consisting of an outer corrosion-resistant color-coated steel plate, a middle polyurethane foam layer of over 50mm, and an inner fire-resistant gypsum board. The polyurethane foam layer achieves efficient thermal insulation by blocking heat conduction. According to China's Technical Standard for Steel Structure Integrated Houses, the heat transfer coefficient of walls in residential containers should be ≤0.45W/(㎡·K). The closed-cell structure of polyurethane makes its thermal insulation efficiency 1.8 times that of traditional brick-and-mortar walls. Actual measurements show that in summer, the temperature inside the container rises 22 minutes slower than outside, and in winter, the indoor temperature drops by only 1.3℃ after being closed for 8 hours, significantly improving living comfort.
2. Fire prevention and structural safety materials
Polyurethane also serves a fire prevention function in container houses. For example, packing-box container houses use fire-resistant polyurethane sandwich panels, which meet building fire prevention regulations by adding flame retardants. Additionally, polyurethane adhesives are used in foldable container houses to bond steel plates with polystyrene, forming a composite structure that ensures waterproof performance and enhances overall strength. Some manufacturers use polyurethane spraying processes to achieve integrated forming of building envelope parts, reducing cold and hot bridge effects. Meanwhile, the closed-cell structure blocks moisture intrusion, extending the service life of the houses.
3. Corrosion prevention and surface protection materials
In the field of maritime containers, polyurethane topcoats are a key component of the corrosion protection system. For example, a dedicated three-layer coating system consisting of an epoxy zinc-rich primer, an epoxy mica intermediate coat, and an acrylic polyurethane topcoat provides long-term protection for over 10 years through the sacrificial anode action of zinc powder, the shielding effect of the intermediate coat, and the weather resistance of the topcoat, withstanding harsh marine environments with high salt spray, strong ultraviolet radiation, and extreme temperature differences.
4. Adaptability to construction processes
Polyurethane materials can be applied to container houses in various forms, such as spraying, foaming, and sandwich panels. For example, manufacturers in the Chongming area use polyurethane spraying processes to treat building envelope parts, offering high construction efficiency and the ability to fully cover corner curves. Modular container houses, on the other hand, achieve standardized production through prefabricated polyurethane-edged sandwich panels, shortening on-site assembly cycles.
