Heat-insulating and noise-reducing nonwoven composite material for automobile interior trim and preparation method thereof

[0022] Example 1

[0023] PP fiber, PET fiber and hollow PET fiber were weighed and mixed respectively, and the mixing ratio was 50 wt % of PP fiber, 20 wt % of PET fiber, and 30 wt % of hollow PET fiber.

[0024] After the fiber is initially mixed and opened by the pre-opener, it is sent to the opener for sufficient mixing and opening. as attached figure 1 As shown, the open fiber feedstock is fed into a carding machine, where the feedstock fibers are processed into a thin web consisting essentially of single fibers and the fibers are straightened in parallel. The four-curtain lay-up method is adopted, and the thin net is laid on the net curtain for output. After that, the output thin web is sent to the pre-needling machine, and it is needle-punched into a pre-needle felt. In this example, the pre-needled felt has a surface density of 350g/m2. 2 , and then the thin felt is superimposed and sent to the main needling machine for superimposed needling, and continues to be superimposed with the pre-needling felt for needling. 2 of finished felt.

[0025] Attached figure 1 As shown, after the above-mentioned fiber mat is cut, the surface is covered with hot-melt film and fabric respectively, and the fabric can be knitted fabric or non-woven fabric, etc., and then it is sent into a hot press, and molded according to the selected mold. The molding parameters selected in this example are: molding temperature of 200° C., molding pressure of 4 MPa, and molding time of 4 min. After cooling, it is trimmed into the final product with a cutter.

[0026] The performance parameters of the product of this example are: flexural strength 3.4MPa, flexural modulus 215MPa, longitudinal and transverse dimensional change rates of -0.04% and -0.08%, respectively, thermal conductivity at room temperature 0.043W/m·K, at 100 ~ 5K Hz The average sound absorption coefficient in the sound frequency range is 0.27.

[0027] Example 2

[0028] PP fiber, PET fiber and hollow PET fiber were weighed and mixed respectively, and the mixing ratio was 50 wt % of PP fiber, 10 wt % of PET fiber, and 40 wt % of hollow PET fiber.

[0029] Using the method described in Example 1, the fibers were sequentially mixed and opened, carded and laid into a web, pre-needled, and main-needed. The surface density of the pre-needled felt in this example is 320g/m2 2 , the needling pass is 4, and the final areal density is about 1300g/m 2 of finished felt.

[0030] Using the method described in Example 1, the above-mentioned fiber mat is molded. The molding parameters selected in this example are: molding temperature 210° C., molding pressure 4 MPa, and molding time 4 min. After cooling, the edges are trimmed into the final product.

[0031] The performance parameters of the product of this example are: flexural strength of 3.0MPa, flexural modulus of 200MPa, longitudinal and lateral dimensional change rates of -0.04% and -0.09%, respectively, thermal conductivity at room temperature of 0.04W/m·K, at 100 ~ 5K Hz The average sound absorption coefficient in the sound frequency range is 0.26.

[0032] Example 3

[0033] PP fiber, PET fiber and hollow PET fiber were weighed and mixed, and the mixing ratio was 50wt% of PP fiber, 1wt% of PET fiber, and 49wt% of hollow PET fiber.

[0034] Using the method described in Example 1, the fibers were sequentially mixed and opened, carded and laid into a web, pre-needled, and main-needed. The surface density of the pre-needled felt in this example is 330g/m2 2 , the needling pass is 3, and the final areal density is about 1000g/m 2 of finished felt.

[0035] Using the method described in Example 1, the above-mentioned fiber mat is molded. The molding parameters selected in this example are: molding temperature 160° C., molding pressure 2 MPa, and molding time 2 min. After cooling, the edges are trimmed into the final product.

[0036] The performance parameters of the product in this example are: flexural strength 3.0MPa, flexural modulus 219MPa, longitudinal and transverse dimensional change rates of -0.18% and -0.14%, respectively, thermal conductivity at room temperature 0.043W/m·K, at 100 ~ 5K Hz The average sound absorption coefficient in the sound frequency range is 0.25.