Do not use "styrofoam" as the lowest cost vehicle sound insulation material.

"Foam rubber", also known as foam rubber, is a semi-synthetic polymer that is filled into steel cylinders under high pressure. The so-called semi-synthesis concept refers to the lack of sufficient chemical reaction between the catalytic gas and oxygen; When in use, it is necessary to release the internal pressure to eject the material and react with oxygen in the air to form a "honeycomb" rubber body.

Can polystyrene foam sound insulation?

Standard answer: yes. The formation of noise is irregular air vibration, which is caused by internal combustion engine operation, air friction (wind noise), tire friction and vibration (collision) of interior parts, thus causing sound waves formed by air vibration. Key points: The vibration of the engine will cause the vibration of the frame. There is air in the space between the frame and the cover around the cockpit, and the air vibration will cause the "Dolby Surrounding Level" noise.

When styrofoam is used to fill the cavities of A/B columns, interior trim panels and chassis beams of vehicles, the sound waves generated by structural vibration will be reflected by cellular styrofoam and weakened. The noise entering the car will naturally become much smaller, so styrofoam can really reduce the noise, and its automatic response after spraying greatly reduces the construction difficulty. A hose long enough with styrofoam can soundproof anyone's car. But because the operation is too simple, this problem is ignored.

toxic substance

The main components of styrofoam are "polyurethane prepolymer, foaming agent and catalyst", so there is no need to worry about the influence of these substances in the pressure cooker. However, after the prepolymer is sprayed into the air to react with water molecules and oxygen, there will be two kinds of residues in the solid styrofoam.

Polyether polyols

Diisocyanate

Almost 65,438+0,000% of the first polyol used formaldehyde in the manufacturing process, so I don't need to go into details about how serious this substance is to organisms. Diisocyanate can also be inhaled from respiratory tract, causing damage to nasal mucosa, lungs, skin and other organs. Severe inhalation at high concentration may cause pulmonary fibrosis.

Other substances: Toluene diisocyanate and dimethyl methane diisocyanate are commonly used in industrial manufacturing. Both of these substances have strong pungent odor, and the latter will produce odor in high temperature environment; The first one is mainly used to make foam rubber, and the second one is mainly used to make rigid foam plastics, synthetic rubber, synthetic leather (artificial leather) and so on. There are already some rubber, foam and artificial leather interiors in the car to prevent collision or vibration, so some new cars will have the problem of excessive air pollutants. Then, if this "sound-proof foam rubber" is added, will the car become a "gas chamber"?

Summary: It is suggested that the automobile sound insulation should be constructed from the outside of the car, so as to ensure that the swept airflow will not enter the car as much as possible; For example, the sound insulation of the engine compartment firewall or wheel eyebrows, as for the car, it is not recommended to upgrade later as far as possible, because no one can guarantee that harmful substances will not exceed the standard.

Many modified and upgraded vehicles will have a strange smell, which is not unpleasant but not "fragrant", but many people call this smell "aroma" and it is generally accepted. I don't know that these smells are very harmful to human body. If eczema or other symptoms occur during high-frequency driving, it is recommended to conduct a comprehensive inspection of the air quality inside the car.