Low-odor polyurethane sealant for automobiles and preparation method of low-odor polyurethane sealant

Abstract

The invention provides a low-odor polyurethane sealant for automobiles and a preparation method of the low-odor polyurethane sealant. The preparation method comprises the following steps: preparing alayered mesoporous birnessite-type MnO2 nanosphere supported deodorant filler, and carrying out vacuum mixing and stirring on the layered mesoporous birnessite-type MnO2 nanosphere supported deodorantfiller with a isocyanate terminated polyurethane prepolymer in a high-speed stirring kettle, then adding a thixotropic agent, a plasticizer and a curing accelerator, and carrying out vacuum stirringto obtain the mesoporous birnessite-type MnO2 modified low-odor polyurethane sealant. The method provided by the invention overcomes the technical problem that heavy odor is generated when a polyurethane sealant prepared in the prior art is used for automotive interior decorations. A deodorant is supported in layered mesoporous birnessite-type MnO2 nanospheres, so that small molecule volatile matter can be fully adsorbed and decomposed, birnessite-type MnO2 can convert formaldehyde in the automobiles into carbon dioxide and water at room temperature, and odor diffusion of the polyurethane sealant can be remarkably reduced.

Description

technical field [0001] The invention relates to the field of sealants, in particular to a low-odor polyurethane sealant for automobiles and a preparation method thereof. Background technique [0002] With the rapid development of society and the improvement of people's living standards, automobiles have become the preferred means of transportation for people to travel, and when the vehicle is driving and parking, the interior is usually a closed environment. In a closed environment, when the car body is exposed to direct sunlight, the temperature inside the vehicle will rise rapidly. If the odor emitted by the vehicle interior materials is not effectively controlled within the comfortable range of the human sense of smell, it will greatly affect the occupants' health. comfort and endanger human health. At present, most of the materials traditionally used in automotive interior parts have low odor at room temperature and are not easy to detect by human sense of smell, but th...

AI Technical Summary

Problems solved by technology

[0006] Patent CN103102859A provides a polyurethane sealant containing a low-volatility catalyst, which uses a high-molecular-weight bismorpholine-based polyoxyethylene ether catalyst to minimize VOC. However, it is difficult to avoid degradation into small molecules during long-term use. adverse impact on the environment

Patent CN106753181A discloses a kind of odorless, low TVOC polyurethane sealant for automobile interior decoration. In this invention, the liquid material polyether polyol, plasticizer and deodorant are subjected to adsorption reaction in advance, and then the material liquid is centrifuged and dehumidified. The combination of pressure and suction filtration removes the deodorant that adsorbs small molecules with odor, and further reduces the odor of raw materials through pretreatment of other components, eliminates small molecules that cause odor, and solves the problem of heavy odor of polyurethane sealants. However, the processing process is cumbersome, the polyurethane sealant is not viscous enough, and the harmful substances such as volatilized formaldehyde cannot be fully eliminated

[0007] Aiming at the technical problems that the currently prepared polyurethane sealant will produce heavy odor when used in automotive interiors, although the existing solutions reduce the release of VOC to a certain extent, the process steps are cumbersome and the treatment effect is not good. Therefore, a simple method is proposed. The process scheme to prepare low-odor polyurethane sealant is of great significance to car body air purification and human health