Optimization of Fireproof Adhesive Construction Technology on Complex Curved Surfaces and Porous Substrates and Improvement of Bonding Uniformity

 

In fields such as construction, shipbuilding, and aviation, the demand for fireproof treatment of complex curved surfaces and porous substrates (e.g., wood, concrete) is increasing. The effective application of fireproof adhesives faces challenges such as surface tension and uneven penetration, which affect bonding quality and fireproof performance. This paper deeply discusses optimization methods for fireproof adhesive construction technology on complex curved surfaces and porous substrates (wood, concrete, etc.), and proposes systematic solutions to surface tension and penetration issues to achieve uniform and reliable bonding effects.

 

With the diversification of building materials and industrial products, the application of complex curved surface designs and porous substrates such as wood and concrete has become increasingly widespread. As a key material ensuring fire safety, the construction quality of fireproof adhesives on these special surfaces directly affects overall fireproof performance. However, the irregular shape of complex curved surfaces and the high permeability and uneven surface of porous substrates often cause problems such as uneven coating and insufficient bonding strength of fireproof adhesives. Therefore, it is urgent to optimize the construction technology and solve the troubles caused by surface tension and penetration.

Analysis of Characteristics of Complex Curved Surfaces and Porous Substrates

Construction Difficulties of Complex Curved Surfaces

Complex curved surfaces have structures such as curvature changes, corners, and grooves, making it difficult for fireproof adhesives to adhere uniformly under the action of gravity and surface tension. During spraying or scraping, fireproof adhesives easily accumulate in concave areas, while convex areas may have excessively thin or even missed coatings. At the same time, the curvature changes of curved surfaces also affect the contact angle and pressure between construction tools and the substrate surface, further reducing construction uniformity.

Particularities of Porous Substrates

Porous substrates such as wood and concrete have rich pore structures, which generate strong capillary suction on fireproof adhesives, leading to rapid penetration. On one hand, excessive penetration of fireproof adhesives into the substrate results in insufficient surface coating thickness, affecting fireproof and bonding performance; on the other hand, differences in porosity and pore size in different areas lead to uneven penetration of fireproof adhesives, ultimately causing inconsistent surface coating thickness and bonding strength. In addition, wood surfaces may contain substances such as oils and waxes, while concrete surfaces may retain contaminants such as release agents and dust, both of which affect the wetting and adhesion of fireproof adhesives.

 

Optimization of Fireproof Adhesive Construction Technology

Substrate Pretreatment

For complex curved surface substrates, cleaning should be carried out first: use high-pressure air or soft brushes to remove surface dust, oil, and other impurities to ensure a clean surface. If the curved surface has sharp edges and corners, sanding and rounding should be performed to reduce the accumulation and flow of fireproof adhesives at the edges.

For porous substrates, wood needs to be sanded to remove surface oils, burrs, and aging layers, making the surface smooth and uniform while closing some large pores; concrete substrates should be ground with steel brushes or sandpaper to remove laitance, release agents, and other contaminants, then rinsed with clean water and allowed to dry completely before construction. For substrates with extremely high porosity, a primer sealer can be pre-applied to fill part of the pores, reduce substrate permeability, and enhance the interfacial bonding force between the substrate and fireproof adhesive.

Selection of Construction Tools and Methods

For complex curved surface construction, customized curved surface scrapers or flexible rollers can be used. Customized scrapers are designed according to the shape of the curved surface to ensure close fitting with the substrate surface and uniform scraping of fireproof adhesives; flexible rollers can adapt to the curvature changes of the curved surface and achieve uniform distribution of fireproof adhesives through rolling coating. For particularly complex parts where traditional tools are difficult to use, small-scale spraying equipment such as air-assisted airless sprayers can be selected to achieve uniform spraying by precisely controlling the spraying pressure and distance.

For porous substrates, multiple thin coatings can be applied to control the penetration of fireproof adhesives. Use brushes or short-haired rollers for coating: after each coating, wait for a certain period until the fireproof adhesive preliminarily dries to form a surface layer with certain strength, then apply the next coating to gradually reach the required coating thickness. In addition, a combination of scraping and rolling can be used: first scrape to fill the pores, then roll to smooth the surface.

Control of Construction Environment

The ambient temperature and humidity during fireproof adhesive construction significantly affect the construction effect. Generally, the construction ambient temperature should be controlled between 5°C and 35°C, with humidity not exceeding 80%.Too low temperature will cause the viscosity of fireproof adhesive to increase and fluidity to deteriorate, making it difficult to coat uniformly; too high temperature may cause the fireproof adhesive to dry too quickly, affecting its wetting and penetration into the substrate. Excessive humidity easily forms condensed water on the substrate surface, affecting the adhesion of fireproof adhesive. Meanwhile, good ventilation should be maintained during construction to accelerate the volatilization of solvents or moisture in the fireproof adhesive and promote drying and curing.

 

Technical Measures to Solve Surface Tension and Penetration Issues

Overcoming Surface Tension

Adding appropriate surfactants to the fireproof adhesive formula can reduce the surface tension of the fireproof adhesive and improve its wettability on the substrate surface. Nonionic surfactants and silicone-based surfactants can effectively improve the spreading performance of fireproof adhesives on complex curved surfaces and porous substrates, reducing defects such as craters and flow marks caused by surface tension.

In addition, heating can be used during construction to reduce the surface tension of fireproof adhesives. Preheating the fireproof adhesive or heating the substrate surface can improve the fluidity of the fireproof adhesive, allowing it to spread more evenly on the substrate surface. However, care should be taken to control the heating temperature to avoid premature curing of the fireproof adhesive or damage to the substrate.

Addressing Penetration Issues

Adjusting the viscosity of fireproof adhesives is an important means to control penetration. By adding thickeners such as cellulose ethers and bentonite, the viscosity of fireproof adhesives can be increased to slow down their penetration rate in porous substrates, keeping more fireproof adhesives on the substrate surface to form uniform coatings. At the same time, the curing rate of fireproof adhesives can be optimized by adopting fast-curing systems, so that the fireproof adhesives start to cure before penetrating too deeply into the substrate, thereby controlling the penetration amount.

Additionally, adding appropriate fillers such as calcium carbonate and talcum powder to fireproof adhesives can fill the pores on the substrate surface, reduce the penetration path of fireproof adhesives, and increase the thickness and strength of the coating, helping to achieve uniform bonding.

 

Quality Inspection and Control

After construction, quality inspection of fireproof adhesive coatings is required. Use visual inspection to observe whether the coating surface is smooth and uniform, and whether there are defects such as missed coating, sagging, and bubbles; use a coating thickness gauge to measure the coating thickness and ensure it meets the design requirements. For bonding strength, pull-off tests can be conducted, and multiple test points can be selected at different locations to determine whether the bonding strength is uniform and reliable. If quality problems are found, timely repair measures should be taken, such as local patching or sanding and re-coating.

Conclusion

Through in-depth analysis of the characteristics of complex curved surfaces and porous substrates, optimizing fireproof adhesive construction technology from aspects such as substrate pretreatment, selection of construction tools and methods, and control of construction environment, and adopting targeted measures to overcome surface tension and penetration issues, the construction quality of fireproof adhesives on special substrates can be effectively improved, achieving uniform and reliable bonding effects. In practical applications, it is still necessary to further explore and improve construction technology according to specific substrate types, fireproof adhesive properties, and project requirements to ensure the effective realization of fire safety performance. In the future, with the continuous development of materials science and construction technology, the construction technology of fireproof adhesives on complex surfaces will become more perfect and efficient.

For more about optimization of fireproof adhesive construction technology on complex curved surfaces and porous substrates and improvement of bonding uniformity, you can pay a visit to Deepmaterial at https://www.adhesivesmanufacturer.com/ for more info.