CN-121992578-A - Preparation process of lightweight environment-friendly automobile interior nonwoven fabric

CN121992578ACN 121992578 ACN121992578 ACN 121992578ACN-121992578-A

Abstract

The invention relates to the technical field of textile, and discloses a preparation process of a lightweight environment-friendly automotive interior nonwoven fabric. The process comprises preparing three-layer fiber components including regenerated polyester, bio-based polyester and natural fiber, forming a sandwich structure by adopting multi-bar parallel net, on-line electrostatic spinning bio-based microporous membrane between layers, applying low-melting-point hot melt adhesive powder, performing needle punching reinforcement and gradient hot air solidification, and performing hot punching molding by combining far infrared preheating with a cold pressing mold. The invention improves the sound absorption coefficient while reducing the gram weight, and has excellent flame retardance, self-cleaning performance and full life cycle closed loop recovery capability.

Inventors

Lin Cungen
LI NING
GAO JINHUA
BI SIYUAN
Lin Zhaomeng
YIN FANG

Assignees

山东恒越汽车内饰件有限公司

Dates

Publication Date: 20260508
Application Date: 20260408

Claims (10)

1. The preparation process of the lightweight environment-friendly automotive interior nonwoven fabric is characterized by comprising the following steps of: (1) Separately preparing a first fiber component for constructing a high-density flame-retardant layer, a second fiber component for constructing a middle-layer sound-absorbing layer, and a third fiber component for constructing an interior decoration layer (2) Respectively opening, mixing and carding the first fiber component, the second fiber component and the third fiber component by adopting a multi-bar carding machine and a cross lapping machine to form a single-layer fiber thin net, and carrying out online superposition according to the sequence of the third fiber layer, the second fiber layer and the first fiber layer to form an initial fiber blank with a three-layer structure; (3) In the lamination process, respectively constructing a bio-based degradable microporous membrane on line and in situ by using an electrostatic spinning process at the interfaces between the first fiber layer and the second fiber layer and between the second fiber layer and the third fiber layer, and dispersing low-melting-point bio-based polyester copolymer hot melt adhesive powder at the interfaces to form a hybrid interface containing a nanoscale functional membrane and a powder bonding system; (4) The needling treatment is carried out on the initial fiber blank by using a needling machine provided with special-shaped needles, and components of each layer are primarily locked in physical space through vertical penetration and entanglement of fibers in the thickness direction, so that a non-woven felt material with preset tensile strength is formed; (5) Sending the pre-reinforced felt material into a circulating hot air penetrating heating box, and setting a preheating zone, a fusion bonding zone and a cooling shaping zone which have gradients to enable the hot melt adhesive powder to be fused and infiltrated at a fiber junction to form a dot matrix bonding structure, and simultaneously inducing fibers in a second fiber layer to be thermally contracted to improve the fluffiness; (6) And in the forming and post-treatment stage, the cured felt material is subjected to hot stamping forming to adapt to the complex curved surface contour of the automobile interior trim, and then the surface of the decorative layer is subjected to plasma activation and anti-fouling treatment.
2. The process for preparing the lightweight environment-friendly automotive interior nonwoven fabric according to claim 1, wherein the first fiber component comprises regenerated polyethylene terephthalate fibers, bio-based polyester fibers and natural fibers subjected to alkali treatment, and a halogen-free flame retardant is loaded in the fibers; The second fiber component comprises high-curl regenerated polyethylene terephthalate fibers and hollow bio-based polyester fibers; The third fiber component comprises regenerated polyethylene terephthalate fibers, bio-based polyester fibers and hyperbranched polymer functionalized fibers loaded with a photocatalyst.
3. The preparation process of the lightweight environment-friendly automotive interior nonwoven fabric is characterized in that the specific proportion of the first fiber component is 40-60% of regenerated polyethylene terephthalate fiber, 20-30% of bio-based polyester fiber and 20-30% of natural fiber according to mass percent.
4. The process for preparing the lightweight environment-friendly automotive interior nonwoven fabric according to claim 2, wherein the natural fiber is at least one selected from flax, jute and sisal, and the natural fiber is subjected to sodium hydroxide solution soaking degumming and alkali treatment before blending.
5. The preparation process of the lightweight environment-friendly automotive interior nonwoven fabric is characterized in that in the second fiber component, the number of curls of the high-curling regenerated polyethylene terephthalate fibers is 15-22 per 25 millimeters, the hollowness of the hollow bio-based polyester fibers is 25-35%, and the mass ratio of the high-curling fibers to the hollow fibers in the second fiber component is 1:1.
6. The process for preparing the lightweight environment-friendly automotive interior nonwoven fabric according to claim 2, which is characterized in that the preparation process of the hyperbranched polymer functionalized fiber is as follows: synthesizing hydroxyl-terminated hyperbranched polyester and preparing into an aqueous solution with the mass fraction of 10%; Adding anatase titanium dioxide particles or zinc oxide particles into the aqueous solution through ultrasonic dispersion; The obtained compound is loaded on the surface of the regenerated polyethylene glycol terephthalate fiber by adopting a padding process.
7. The process for preparing the lightweight environment-friendly automotive interior nonwoven fabric according to claim 1, wherein in the step (2), the gram weight of the middle layer sound absorbing layer formed by the second fiber component is controlled to be 200-500 g/square meter, the gram weight of the flame retardant layer formed by the first fiber component is controlled to be 100-150 g/square meter, and the gram weight of the decorative layer formed by the third fiber component is controlled to be 60-100 g/square meter, so that a symmetrical or asymmetrical gradient structure with decreasing and increasing density from outside to inside is formed.
8. The preparation process of the lightweight environment-friendly automotive interior nonwoven fabric is characterized in that in the step (3), the bio-based degradable microporous membrane is formed by spinning after polylactic acid and polylactic acid-glycolic acid copolymer are mixed according to a mass ratio of 7:3, in the electrostatic spinning process, the relative humidity of the environment is controlled to be 40% -50%, the ambient temperature is controlled to be 25 ℃ -30 ℃, a voltage of 15 kilovolts-25 kilovolts is applied through a multi-nozzle electrostatic spinning device, and the solution propelling speed is set to be 0.8 milliliter-1.5 milliliter per hour.
9. The process for preparing the lightweight environment-friendly automotive interior nonwoven fabric according to claim 1, wherein in the step (3), the hot melt adhesive powder is low-melting-point bio-based polyester copolymer powder, and in the powdering process, the adhesive powder is uniformly distributed on the interface of the fiber layer through a mechanical vibration powdering machine.
10. The process for preparing the lightweight environment-friendly automotive interior nonwoven fabric according to claim 1, wherein in the step (4), the needling reinforcement process adopts needles with triangular cross sections or fork needles, the needling depth is controlled to be 4-8 mm, the needling frequency is 600-1000 times per minute, and the needling density is distributed to be 50-150 times per square centimeter.

Description

Preparation process of lightweight environment-friendly automobile interior nonwoven fabric Technical Field The invention belongs to the technical field of textiles, and particularly relates to a preparation process of a lightweight environment-friendly automobile interior nonwoven fabric. Background In the prior art system, in order to make the lightweight polyester non-woven fabric capable of taking noise reduction, flame retardance and basic structural strength into consideration, the production enterprises generally adopt material superposition process logic. The mainstream scheme is to compound a layer of expanded polytetrafluoroethylene microporous membrane between high-density fiber net layers, and to assist with a petroleum-based damping gel or hot melt adhesive coating. The expanded polytetrafluoroethylene film generates viscous friction and heat dissipation effects through the complex micropore channels, and the damping glue converts vibration energy into heat energy by utilizing the viscoelasticity of the polymer, so that the aim of synergetic noise reduction is achieved. The expanded polytetrafluoroethylene can hardly be degraded in natural environment due to extremely high chemical bond energy and physical stability, and in the recycling process, chemical incompatibility exists between the fluoropolymer and the polyester fiber of the main body, so that the whole material can not be separated efficiently by physical or chemical means, and finally can only be treated by incineration or landfill. The hot-melt adhesive system relied on interlayer bonding is mostly non-renewable synthetic polymers, and the risk of releasing volatile organic compounds exists in the production and use processes, and each functional layer is locked on a physical structure, so that the fiber component and the film component are difficult to realize high-purity classified recovery when the life cycle is ended. With the increasing diversification of the functional requirements of interior trim parts, the single sound absorption function cannot meet the market requirements, and the additional functions of flame retardance, self-cleaning, odor removal and the like are often realized by adding a coating or a composite functional film. The differences in heat shrinkage, flexural modulus and rheology between the different material layers directly lead to a very uneven internal stress distribution of the facing when hot stamping or vacuum forming, especially when dealing with complex, high curvature geometries. Such stress mismatch tends to induce interlayer delamination, surface wrinkling or severe flatness degradation at the stress concentrations, greatly limiting the design flexibility of the interior trim piece. Disclosure of Invention In order to achieve the aim of the invention, the invention provides a preparation process of a lightweight environment-friendly automotive interior nonwoven fabric, which aims to solve the technical contradiction between lightweight, acoustic performance, environment-friendly recoverability and complex curved surface formability of the traditional automotive interior material by constructing a sandwich integrated structure with density gradient and acoustic impedance mismatch effect and combining a bio-based functional material and a green bonding technology. The invention provides a preparation process of a lightweight environment-friendly automotive interior nonwoven fabric, which has the core logic that the integral lightweight and functional integration of a material is realized through the precise proportioning of multicomponent fibers, the differentiated construction of a plurality of layers of nonwoven nets and the systematic integration of a bio-based microporous membrane and a green bonding system. The preparation process comprises the following steps: In the raw material preparation stage, a first fiber component, a second fiber component and a third fiber component are prepared respectively. The first fiber component is a high-density flame-retardant layer raw material, is formed by physically mixing regenerated polyethylene glycol terephthalate fibers, bio-based polyester fibers and natural fibers according to a preset proportion, and is preloaded with a halogen-free flame retardant on the surface of the fibers or in the matrix. The fineness of the regenerated polyester fiber is controlled to be in the range of 1.5 to 3.0 deniers, the length is 38 to 65 millimeters, and the mass ratio of the regenerated polyester fiber in the first fiber component is 40 to 60%. The bio-based polyester fiber adopts polylactic acid or polybutylene succinate, and the melting point of the bio-based polyester fiber is lower than that of the regenerated polyester fiber, and the bio-based polyester fiber is used as a structural support and auxiliary bonding component. The natural fiber is at least one of flax, jute or sisal, is degummed and alkali treated, has fiber length distributed between 40 mm and