1. Test items

Sound absorption performance: Given that its porous structure is used for sound absorption and noise reduction, it is necessary to test the sound absorption coefficient under sound waves of different frequencies. In theaters and recording studios, the focus is on the absorption of mid- and high-frequency sounds, such as the 2000-8000Hz frequency band, which is rich in human voices and musical instruments. Only with good sound absorption can a pure acoustic environment be created to avoid echo and reverberation interference.

Insulation and thermal insulation performance: The core is to measure the thermal conductivity. The lower the value, the better the thermal insulation. When used in exterior walls of houses and refrigerated compartments, it is necessary to ensure that polyurethane foam can effectively block heat transfer and reduce energy consumption under different temperature differences, such as minus 20℃ outdoors and 20℃ indoors in winter, and high temperatures of 40℃ and refrigerated temperatures of 0℃ in summer.

Mechanical properties: including compressive strength, elastic modulus, etc. When used as sofa and mattress filling, it needs to withstand repeated pressure from human weight, and the compressive strength must meet the standard to prevent rapid collapse; the elastic modulus determines the rebound performance, and the appropriate elasticity makes sitting and lying comfortable, and the shape can be quickly restored after long-term use.

Chemical stability: Test its acid and alkali resistance and aging resistance. For example, in a chemical workshop, it may be exposed to acid and alkali mist, and it is exposed to the sun and rain for a long time outdoors. It is necessary to ensure that the material does not decompose or become brittle, maintain the stability of structure and performance, and extend the service life.

2. Testing method

Sound absorption test: In a professional anechoic chamber, a sound wave generator is used to emit a sound wave of a specific frequency. After passing through a polyurethane foam sample, the receiver measures the sound wave attenuation, calculates the sound absorption coefficient, and draws the sound absorption spectrum with multi-frequency testing for comprehensive evaluation.

Thermal insulation test: Using the protective hot plate method or the heat flow meter method, the sample is placed between two plates with a temperature difference, and the heat flux density is measured by a heat flow sensor. The thermal conductivity is calculated based on the temperature difference, and the temperature gradient test of different seasons and environments is simulated.

Mechanical analysis: Universal material testing machine is used to conduct static compression, tension and bending tests on samples, record force and deformation data, obtain compressive strength, tensile strength and elastic modulus, simulate actual stress scenarios and repeated loading, and examine durability.

Chemical tolerance: Soak the sample in acid and alkali solution for a certain period of time, observe changes in appearance, weight and performance; place it in an aging box to simulate light, temperature and humidity cycles, conduct regular sampling, and use infrared spectroscopy to analyze chemical structure changes.

3. Testing standards

The industry has strict regulations. The sound absorption coefficient is graded according to the usage scenario, and the architectural acoustics requirements are relatively high; the thermal conductivity coefficient is set at an upper limit according to the insulation purpose; the mechanical performance indicators are different according to the product type, such as furniture and buildings; chemical stability is quantified for acid and alkali resistance and aging time to ensure the bottom line of product quality.

4. Significance of testing

For consumers, accurate testing ensures that they can purchase high-performance polyurethane foam products, such as quiet living environment, energy-saving home appliances, and comfortable furniture. Enterprises optimize production according to standards, enhance competitiveness, and establish brands. From the overall situation of the industry, standardized testing promotes technological innovation, expands the application boundaries, and allows materials to add color to life.