Insulation with Polyurethane Spray Foam

Polyurethane Spray Foam Insulation Heat, defined as a form of energy, tends to move from the area of higher temperature to the area of lower temperature between two environments at different temperatures. This causes heat loss from structures during cold weather and heat gain during summer. Measures taken to reduce this heat transfer and maintain thermal balance within buildings throughout the year are called thermal insulation. In recent years, due to declining energy resources worldwide, rising energy costs and increased global warming following greater use of fossil fuels are increasing demand for thermal insulation materials in the construction sector. Selection criteria for insulation materials in buildings initially leaned towards inexpensive and medium-quality products, but now sought properties are directly proportional to fire resistance, fire reaction and thermal conductivity values. The priority of the insulation material used has shifted from simply providing long-term thermal insulation to also ensuring life safety. Since all furniture and items such as curtains found in homes are combustible, and fires occur when heat sources such as electrical contacts, stoves and cookers create heat through certain chemical reactions or friction that brings combustible materials in the environment to ignition temperature, structural measures are needed alongside active fire prevention measures to slow the spread of fire and its harmful effects within the building and to neighboring buildings, and to allow safe evacuation of those exposed to the fire from the affected area. These structural measures taken to limit the harmful effects of fires are called fire insulation. These two properties - materials with excellent thermal insulation and fire resistance - must be used in modern building technologies. Polyurethane systems are among the isolation materials used for these purposes. Polyurethane systems are two-component systems formed as a result of reactions between OH-terminated polyols and NCO-terminated isocyanates. Rigid polyurethane foam (PUR) systems are closed-cell, low-density isolation and construction materials. Due to the low thermal conductivity of the blowing agent trapped within the cells in the structure, they are among the most preferred materials for insulation. The thermal conductivity coefficient of polyurethane foam systems being λ=0.016-0.024 W/mK provides an important advantage for thermal insulation. Rigid polyurethane foam (PUR) materials are not structurally highly resistant to burning. Flame retardant substances are widely used to improve combustion characteristics. Flame retardant materials provide resistance to burning while causing declines in the mechanical values of the foam system. The release of halogens contained in the structure of flame retardant materials as gas during combustion is also a negative characteristic. In recent periods, more work is being done on polyol systems that have structural non-flammability properties to replace these materials, aiming for better fire resistance and lower gas emissions. The new polyester structure developed by Kobe Polyurethane and products using this material have shown increased fire resistance despite reduced halogen-containing flame retardants. In the Kobepol spray series using these products, density ranges between 30 and 50 kg/m³ have been observed to achieve very good values. In these products, it is fundamentally desired to have a low λ (thermal conductivity coefficient) value and values range between 0.020-0.024 W/mK. Products with very good dimensional stability measure dimensional change at -20°C as % <0.5. Since flammable and combustible gases are not used as blowing agents in the products, they can be safely used by users and will involve no risk during application. [caption id="attachment_138348" align="aligncenter"] Figure 1: Insulation application with polyurethane spray[/caption] An important point to remember here is that the primary characteristic of polyurethane foam systems is thermal insulation, not fire insulation. The purpose is to prevent flame spread in any fire. The TS EN ISO 11925-2:2020 test method measures the flammability of building materials when directly exposed to flame. The sample surface is continuously exposed to a flame source with 1 cm flame height for 15 seconds; if the flames on the sample surface self-extinguish when the flame source is removed after this period and the flame height does not exceed 15 cm on the sample surface, the product is classified as B2 class. [caption id="attachment_138349" align="aligncenter"] Figure 2: B3 class, competing B2 product and Kobepol product[/caption] As Kobe Polyurethane, with polyurethane spray systems in our product range classified as B2 fire resistance class, we provide solutions to meet our customers' various needs. [caption id="attachment_138350" align="aligncenter"] As Kobe Polyurethane, with polyurethane spray systems in our product range classified as B2 fire resistance class, we provide solutions to meet our customers'
various needs.[/caption]

References:

1. Egolf Global, 2. Dr. Kaneyoshi Ashida, Handbook of Polymeric Foams and Foam Technology, 3. M. Szycher, Szycher's Handbook of Polyurethanes, 4. www.izoder.org.tr, 5. Hou CT. Adv Appl Microbio 1995;41:1-23. [9] Russel, D., & Smiley, R. A. (1991)., 6. M. Lonescu, Chemistry and Technology of Polyols for Polyurethanes Gülhan Sarıgöl R&D Engineer Kobe Polyurethane