Differences of Polyurethane and Polystyrene
Looking for strategies to reduce the cost of heating and cooling your house while improving comfort levels? If so, the advantages of foam insulation might be of interest to you. Spray foam (polyurethane) insulation and rigid foam (polystyrene) are the two primary varieties
available.
Both polystyrene and
polyurethane are polymers, which are synthetic materials created from long molecular chains. The majority of the atoms in these molecules are hydrogen and carbon.
These materials are produced by industry and used to create various everyday objects. Polystyrene, also known as foam, is often used for extra protection, especially in box packaging of electronic devices. Polyurethane, however, is progressively taking the place of
polystyrene in some circumstances, notably those that call for additional flexibility.
Even though the two can be confused at times, there are variations between them
in terms of composition, the completed goods’ propensity to conduct heat and resist chemicals, and their tolerance for thickness.
Composition Differences
Polystyrene is a polymer containing molecules composed of typically carbon and hydrogen atoms. On the other hand, the molecular formula of polyurethane represents a far more complex polymer built from molecules containing nitrogen, oxygen, carbon, and hydrogen.
Polyurethane’s polymers can be ordered in numerous ways to produce materials with varied degrees of flexibility, unlike polystyrene, which creates a rigid plastic.
Thermal Resistance
A building material’s thermal resistance is gauged by its R-value. An great material for electrical insulation, polyurethane manages to withstand heat nearly twice as well as polystyrene.
The elasticity of polyurethane is also maintained in extremely cold temperatures. But
this resistance varies depending on the thickness and density of each substance.
Weathering, Chemical Resistance, and Abrasion While solvents like gasoline and some insecticides will damage polystyrene, polyurethane is impervious to almost all chemicals.
In terms of resistance to oxidation and sunlight-induced atmospheric degradation, this polymer outperforms polystyrene. In actuality, polyurethane is more resistant to physical assaults and stressors than polystyrene.
Load Support and Noise Reduction
Polyurethane can be used to manufacture load-bearing wheels, mechanical joints, couplings, and machine mounts since it mimics both rubber and plastic. For these tasks, polystyrene lacks flexibility. Polyurethane is helpful in attaining mechanical sound reduction because it shares some characteristics with rubber. This material results in substantially quieter gears.
Insulation Made of Rigid Polystyrene Foam
The most common places to install rigid foam are unfinished walls, roofs, and foundations. In comparison to other types of insulation, the dense product offers a greater R-value, enabling outstanding performance with a very thin thickness. Rigid foam installation lowers
thermal bridging, raises a wall or roof assembly’s Rvalue, and significantly lowers air leaks.
Insulation Made of Rigid Polystyrene Foam
EPS, or expanded polystyrene: EPS is a good material to use for home insulation because it has an R-value of 3.6 to 4.2 per inch. It is the more affordable choice and best suited for above-grade applications.
Extruded polystyrene (XPS): XPS is the ideal insulation for below-grade slabs and foundation walls thanks to its remarkable R-5 per inch value, strong compressive strength, and water resistance.
Insulation Made of Polyurethane Spray Foam
The finest insulation for minimizing air leakage is spray foam. Because it foams in place, you can fill every crevice. Because of this, spray foam is perfect for filling up gaps around floor and wall penetrations as well as irregularly shaped crevices.
However, you must leave installation to the experts because spray foam needs to be made on site and administered while wearing special protective clothes.
Spray Foam Insulation Made of Polyurethane
Polyurethane foam with open cells: A 3.6 per inch Rrating is to be anticipated. Open-cell foam is airtight but permeable to moisture. This makes it perfect for inwarddrying roof systems that require insulation.
Polyurethane foam with closed cells Closed-cell foam gives the highest R-value per thickness of any insulation, at roughly 6.5 R/inch. Its consistency is similar to glue and adds structural integrity to whatever wall or ceiling it is applied to.
Although this alternative is more expensive than open-cell foam, it can be the better choice for your circumstances because it offers a higher R-value per inch and also functions as a vapor retarder. Polystyrene Rigid Foam Panels: Goods and Bads Polystyrene has a greater R-value than fiberglass, cellulose, or mineral wool.
It is also lighter and easier to handle, and there are no fibers that could irritate the skin.
The firm panels resist sagging, give good resistance to water and wind, and are simple to cut and shape with a knife.
The drawbacks of polystyrene include its weak chemical resistance, especially to organic solvents, and its susceptibility to damage from UV light (which restricts its use outside).
The Benefits and Drawbacks of Polyurethane Spray-On Insulation
One of the greatest R-values of any typical insulation, up to R-6 per inch, is found in polyurethane spray foam. It is applied as a liquid, expands to fill spaces, and forms a
strong bond with surrounding surfaces.
This results in a tight air seal and increased structural rigidity. Since closed-cell polyurethane is so water-resistant, it may be utilized to successfully waterproof a variety of surfaces.
A knowledgeable professional is required to mix and install polyurethane insulation properly, which adds to its disadvantages of being more expensive than other
insulating materials. It is advised that all occupants vacate the property for at least 24 hours because it may continue to off-gas until it has fully cured.
Resources
https://byjus.com/chemistry/polystyrene/
https://www.ibpportland.com/blog/polystyrene-vs-polyurethane-insulation
https://sciencing.com/hdpe-vs-ldpe-5968206.html
Compilated by: B. Serhat Cengiz
