PIR Systems for Spray Applications

Energy is one of the most essential basic inputs for sustainable growth in a country. Energy affects the economies of developing countries due to its cost and price volatility. From this perspective, national economies pursue various strategies to minimize their dependence on energy and reduce the impact of price fluctuations. In our country, increasing domestic energy production and using existing energy efficiently are equally important strategies in addressing energy dependence on foreign sources. Today, residential buildings account for a large portion of energy consumption. By covering buildings with thermal insulation materials, residences can create a shield against heat in summer months and cold in winter months. This situation minimizes natural gas and electricity expenses while also protecting insulated buildings from adverse conditions such as moisture and mold.

Materials frequently used for insulation purposes include fiberglass, mineral wool, extruded polystyrene foam (XPS), expanded polystyrene foam (EPS), wood fiber boards, foam glass, phenol foam, cork boards and polyurethane.

The sprayability of polyurethane foams offers application opportunities in many sectors, particularly construction. Some of these sectors include industrial roof insulation, marine vessel insulation, livestock shelter insulation, cold storage insulation, pipeline insulation, and tank-silo insulation. The thickness of materials used is a very important factor in terms of thermal insulation. From this perspective, polyurethane has the lowest thermal conductivity value among insulation materials. Furthermore, due to its closed-cell structure, it does not absorb water and thus protects the facade from moisture and humidity effects. However, the biggest disadvantage of polyurethane foams is that they are flammable. This has caused literature research on polyurethane to focus on fire resistance.

Fire resistance in polyurethane systems is achieved by incorporating various functional or non-functional additive materials and obtaining PIR systems. The advantages of PIR systems over additive materials are primarily;

•Bonding to the polymer, thus preventing migration from the polymer over time, •Greater resistance to heat, •Greater resistance to combustion, •Superior mechanical properties. In PIR systems, isocyanate molecules simply react with each other to form trimer rings. During combustion, these structures carbonize and expand, creating a barrier between the fire source and the foam.While the need for fire-resistant products is increasing in the spray polyurethane foam sector, PIR systems are not being utilized. The reason for this is that almost all machines used in the sector are machines that cannot adjust ratios and operate with a 1:1 volume ratio (1:1.1 by weight) of polyol and isocyanate. However, PIR systems require a high isocyanate ratio (more than 1:1). Flokser Kimya, which has served the polyurethane sector since 2006 and was registered as an R&D center by the Ministry of Industry in 2016, has extensive experience and a wide range of products for spray applications. With products having free-rise densities in the range of 18–1000 kg/m³, in addition to classical spray applications, the company also has sprayable products for different application areas such as decoration and pipe insulation.

Flokser Kimya developed the Creapol RS 3320/36 product, which can be used on 1:1 ratio machines while maintaining PIR properties, thereby meeting the need for fire resistance in the insulation sector. The characteristics of the relevant product are presented in the table below.The Creapol RS 3320/36 product developed in Flokser Kimya laboratories aims to meet the need for combustion resistance in the polyurethane foam sector.

During combustion, the area where the fire source approaches chars, creating a barrier between the foam and the flame. Smoke emissions are minimal. A photograph of the sample after the combustion test conducted according to the TS EN ISO 11925-2 standard is included in the article. The test sample, exposed to flame for 30 seconds, successfully passed the test because the applied flame did not reach the 150mm measurement line within the test duration. The product's quick reaction times that do not cause sagging and the formation of a thick, glossy layer on the surface after application are properties that applicators value. The product's viscosity and working temperatures are designed to be suitable for summer and winter conditions. Its adhesion strength to various types of surfaces after application is very high. The product with a density of 36 kg/m³ has high compressive strength with superior mechanical properties. For this reason, it can be used in floor applications as well as ceiling and wall applications. Creapol RS 3320/36, which contains environmentally friendly blowing agents and causes no environmental harm, has met many consumer expectations and set another milestone in the sector. Yusuf Yivlik - R&D Manager / Flokser Kimya Oğuz Tükek - R&D Director / Flokser Kimya