CN115947986A

CN115947986A - HDPE car callus on sole easily stereotypes

Info

Publication number: CN115947986A
Application number: CN202310021430.0A
Authority: CN
Inventors: 许斌; 林枭; 应霞; 祁杨睿; 李俊峰; 章黎明; 章晓阳; 许杨媚
Original assignee: Haiah Technology Co ltd
Current assignee: Haiah Technology Co ltd
Priority date: 2023-01-07
Filing date: 2023-01-07
Publication date: 2023-04-11
Anticipated expiration: 2043-01-07
Also published as: CN115947986B

Abstract

The invention discloses an HDPE (high-density polyethylene) automobile foot pad easy to shape, and relates to the technical field of high polymer materials. Comprises 100 parts of main material and 25-35 parts of additive in parts by weight; the main body material comprises 60-80 parts of high-density polyethylene and 20-40 parts of linear low-density polyethylene; the additive comprises 10-15 parts of polymer-based montmorillonite nanocomposite, 2-10 parts of compatibilizer and 1-5 parts of antioxidant. The invention uses the high strength and the large modulus of the high-density polyethylene, and the toughness and the flexibility of the high-density polyethylene can be improved by adding the linear low-density polyethylene with the mass content of 30 percent, so that the obtained automobile foot pad is easy to bend under stress and convenient to lay.

Description

HDPE car callus on sole easily stereotypes

Technical Field

The invention belongs to the technical field of high polymer materials, and particularly relates to an HDPE (high-density polyethylene) automobile foot pad easy to shape.

Background

The automobile foot mat is one of the necessary articles for the automobile interior trim, can prevent silt on shoes from entering a vehicle, can reduce vibration and noise, and enables a passenger to feel comfortable. Most foot pads in the market are shaped by using foamed plastics, and because the plastics usually have viscoelasticity, the foot pads rebound to some extent after being bent, so that the shaping is difficult; meanwhile, the conventional automobile foot pad is mainly a PVC (polyvinyl chloride) soft product, is usually in a fixed shape, is mainly prepared by an injection molding or extrusion-mould pressing-cutting process and has higher cost.

High Density Polyethylene (HDPE) is a thermoplastic with a wide application range, has the characteristics of good chemical stability, easy forming and processing and the like, and is developed to the present, and becomes one of important plastic varieties.

For example, CN101240097A is a material special for an automobile foot pad, which comprises the following components in parts by weight: 100 parts of PVC, 5-30 parts of a first component, 80-120 parts of a first plasticizer, 5-20 parts of a second plasticizer, 1-5 parts of a first stabilizer, 1-10 parts of a second stabilizer, 0-1.2 parts of a first lubricant, 0-1.0 part of a second lubricant, 0-200 parts of an inorganic filler and 0-20 parts of a coloring agent.

Disclosure of Invention

The invention aims to provide an easily-shaped HDPE (high-density polyethylene) automobile foot pad, which is prepared by taking linear low-density polyethylene, high-density polyethylene and organic modified montmorillonite as main raw materials and taking a compatibilizer EVA-g-MAH and an antioxidant AT-10 as additives, and solves the problems that the conventional PVC automobile foot pad usually has viscoelasticity, rebounds after being bent and is difficult to shape.

In order to solve the technical problems, the invention is realized by the following technical scheme:

the invention relates to an easily-shaped HDPE (high-density polyethylene) automobile foot pad which comprises 100 parts of main body material and 25-35 parts of additive in parts by weight; the main body material comprises 60-80 parts of high-density polyethylene and 20-40 parts of linear low-density polyethylene; the additive comprises 10-15 parts of polymer-based montmorillonite nanocomposite, 2-10 parts of compatibilizer and 1-5 parts of antioxidant.

Further, the high-density polyethylene/montmorillonite composite material comprises 70 parts by weight of high-density polyethylene, 30 parts by weight of linear low-density polyethylene, 12 parts by weight of polymer-based montmorillonite nanocomposite material, 6 parts by weight of compatibilizer and 2 parts by weight of antioxidant.

Further comprises vinylsilane modified lignin accounting for 0.5-1% of the main material by mass, long fibrilia accounting for 5-10% of the main material by mass and phosphogypsum/red mud mixed powder accounting for 3-8% of the main material by mass.

Further, the mass ratio of the phosphogypsum to the red mud in the phosphogypsum/red mud mixed powder is 3-10; the preparation of the phosphogypsum/red mud mixed powder comprises the following steps: uniformly mixing phosphogypsum and red mud according to a solid-water mass ratio of 1:1, adding deionized water, stirring, standing for 6 hours, filtering, and then drying at 100 ℃; and (3) crushing the obtained solid to obtain the phosphogypsum/red mud mixed powder with the particle size of 12-16 mu m after drying, and then placing the powder in a muffle furnace to dry for 4 hours at 250 ℃ for later use.

Further, the easy-to-shape HDPE automobile foot pad comprises, by weight, 70 parts of high-density polyethylene, 30 parts of linear low-density polyethylene, 12 parts of polymer-based montmorillonite nanocomposite, 6 parts of a compatibilizer, 2 parts of an antioxidant, 0.7 part of vinyl silane modified lignin, 7 parts of long fibrilia and 5 parts of phosphogypsum/red mud mixed powder.

Further, the polymer-based montmorillonite nanocomposite is a polystyrene/montmorillonite nanocomposite, a Gemi i surfactant is adopted to enter a montmorillonite layer through intercalation, the montmorillonite layer is effectively stripped, and nano montmorillonite is prepared under the ultrasonic condition; then, carrying out solution blending on the organic modified montmorillonite and polystyrene to prepare a polystyrene/organic modified montmorillonite composite material; drying and crushing the obtained polystyrene/organic modified montmorillonite composite material to obtain the polystyrene/montmorillonite nano composite material.

Further, the preparation of the long fibrilia comprises the following steps: opening the melting and dipping mould, enabling the continuous natural fiber strips to pass through between a plurality of pairs of lower dipping rollers and upper dipping roller pairs, and simultaneously extruding thermoplastic molten resin into the melting and dipping mould through an extruder connecting device to enable the thermoplastic resin melt to melt and dip the continuous natural fiber strips; and (3) passing the impregnated continuous natural fiber strip between an upper pressing roller and a lower pressing roller of a cooling rolling device, and providing pressure by a pressing roller bullet to realize cooling of the resin melt and secondary dispersion of the natural fiber so as to obtain the continuous natural fiber prepreg.

Further, the preparation of the vinyl silane modified lignin comprises the following steps:

weighing vinyl silane, adding the vinyl silane into a stirring container, adding 70% ethanol solution under the stirring condition of 300r/min at room temperature, then adjusting the pH value of the system to 4-5 by using 5% acetic acid solution, and continuously stirring and hydrolyzing for 2h to obtain vinyl silane hydrolysate;

then weighing dry lignin powder, loading into a high-speed pulverizer, spraying vinyl silane hydrolysate on the surface of the lignin in a spraying manner, continuously pulverizing at 25000r/min, mixing for 2min, taking out a sample, and drying at 105 ℃ for 2h to obtain the vinyl silane modified lignin.

The preparation method of the automobile foot pad comprises the following steps:

stp1, weighing the raw materials in parts by weight;

stp2, adding high-density polyethylene, long fibrilia and linear low-density polyethylene into a high-speed mixer, stirring for 5min, counting vinyl silane modified lignin, and continuously stirring for 1-2min;

stp3, then adding the polymer-based montmorillonite nanocomposite, the phosphogypsum/red mud mixed powder, the compatibilizer and the antioxidant, and continuing to stir for 7-10min;

stp4, uniformly stirring, then extruding in a double-screw extruder, feeding into a desulfurization extruder for extruding, and primarily cooling to obtain a granular mixture;

stp5, putting the granular mixture into a refining extruder for continuous kneading, then carrying out injection molding to produce a high-molecular composite sheet material, and cutting the high-molecular composite sheet material into sheets with equal areas;

stp6, and molding the sheet into the shape required by the foot pad by a molding press.

Compared with the prior art, the invention has the following beneficial effects:

the invention uses the high strength and the large modulus of the high-density polyethylene, and the toughness and the flexibility of the high-density polyethylene can be improved by adding the linear low-density polyethylene with the mass content of 30 percent, so that the obtained automobile foot pad is easy to bend under stress and convenient to lay.

Drawings

FIG. 1 is a preparation process diagram of a preparation method of an easy-to-shape HDPE automobile foot pad according to an embodiment of the invention.

Detailed Description

The preparation method of the easily-shaped HDPE car foot mat provided by the invention comprises the following steps:

stp1, weighing the raw materials in parts by weight;

stp2, adding high-density polyethylene, long fibrilia and linear low-density polyethylene into a high-speed mixer, stirring for 5min, counting vinyl silane modified lignin, and continuously stirring for 2min;

stp3, then adding the polymer-based montmorillonite nanocomposite, the phosphogypsum/red mud mixed powder, the compatibilizer and the antioxidant, and continuing stirring for 8 min;

stp5, continuously kneading the granular mixture in a refining extruder, then carrying out injection molding to produce a high-molecular composite sheet material, and cutting the high-molecular composite sheet material into sheets with equal areas;

Example 1

In the embodiment, the formula of the HDPE car foot mat easy to shape comprises, by weight, 70 parts of high-density polyethylene, 30 parts of linear low-density polyethylene, 12 parts of polymer-based montmorillonite nanocomposite, 6 parts of compatibilizer EVA-g-MAH and 2 parts of antioxidant AT-10.

Example 2

In the embodiment, the formula of the HDPE car foot mat easy to shape comprises, by weight, 70 parts of high-density polyethylene, 30 parts of linear low-density polyethylene, 12 parts of polymer-based montmorillonite nanocomposite, 6 parts of compatibilizer EVA-g-MAH, 2 parts of antioxidant AT-10 and 0.7 part of vinyl silane modified lignin.

Example 3

In the embodiment, the formula of the HDPE car foot mat easy to shape comprises, by weight, 70 parts of high-density polyethylene, 30 parts of linear low-density polyethylene, 12 parts of polymer-based montmorillonite nanocomposite, 6 parts of compatibilizer EVA-g-MAH, 2 parts of antioxidant AT-10, 0.7 part of vinyl silane modified lignin and 7 parts of long fibrilia.

Example 4

In the embodiment, the formula of the easy-to-shape HDPE automobile foot mat comprises, by weight, 70 parts of high-density polyethylene, 30 parts of linear low-density polyethylene, 12 parts of polymer-based montmorillonite nanocomposite, 6 parts of compatibilizer EVA-g-MAH, 2 parts of antioxidant AT-10, 0.7 part of vinyl silane modified lignin, 7 parts of long fibrilia and 5 parts of phosphogypsum/red mud mixed powder.

In the above examples 1 to 4, the mass ratio of the phosphogypsum to the red mud in the phosphogypsum/red mud mixed powder is 3 to 10; wherein the preparation of the phosphogypsum/red mud mixed powder comprises the following steps: uniformly mixing phosphogypsum and red mud, and mixing according to a solid-water mass ratio of 1:1 adding deionized water, stirring, standing for 6h, filtering, and drying at 100 ℃; and (3) crushing the obtained solid to obtain mixed powder of phosphogypsum and red mud with the particle size of 12-16 mu m after drying, and then placing the mixed powder in a muffle furnace to dry for 4 hours at 250 ℃ for later use.

In the above examples 1-4, the polymer-based montmorillonite nanocomposite is a polystyrene/montmorillonite nanocomposite, which employs Gemi n i surfactant to enter the montmorillonite layer through intercalation, effectively strips the montmorillonite layer, and prepares nano montmorillonite under ultrasonic conditions; then, carrying out solution blending on the organic modified montmorillonite and polystyrene to prepare a polystyrene/organic modified montmorillonite composite material; drying and crushing the obtained polystyrene/organic modified montmorillonite composite material to obtain the polystyrene/montmorillonite nano composite material.

In the above examples 1-4, the long fibrilia preparation comprises: opening the melting and dipping die, enabling the continuous natural fiber strips to pass through a plurality of pairs of lower dipping rollers and upper dipping roller pairs, and simultaneously extruding thermoplastic molten resin into the melting and dipping die through an extruder connecting device to enable the thermoplastic resin melt to melt and dip the continuous natural fiber strips; and (3) passing the impregnated continuous natural fiber strip between an upper pressing roller and a lower pressing roller of a cooling rolling device, and providing pressure by a pressing roller bullet to realize cooling of the resin melt and secondary dispersion of the natural fiber so as to obtain the continuous natural fiber prepreg.

In examples 1-4 above, the vinylsilane modified lignin preparation comprised:

Comparative example 100.0 parts by weight of PVC (average degree of polymerization 2500), 1.5 parts by weight of organotin (tin methyl mercaptide TM-181), 5 parts by weight of epoxidized soybean oil, 0.5 part of colorant, 100 parts of filler (ultrafine calcium carbonate) and 0.3 part of monoglyceride stearate were placed in a mixer and mixed for 2 minutes at a rotation speed of 800 rpm and a temperature of 60 ℃. Then, 100.0 parts by weight of dioctyl phthalate (DOP), a plasticizer, was added to the above-mentioned mixer three times, and further stirred at 80 ℃ for 10 minutes at 800 rpm, and then 10.0 parts by weight of a powdery nitrile rubber (33% by mass of nitrile) and 5 parts by weight of EVA (ethylene-vinyl acetate copolymer, in which Vinyl Acetate (VA) is 30% by mass) were added to the above-mentioned mixer, and stirred and mixed at 35 ℃ for 3 minutes at 800 rpm, to obtain a uniformly mixed mixture. And extruding and granulating the mixture in a double-screw extruder, wherein the temperature of each section of the extruder is 100 ℃, and the rotating speed of a screw is 20-30 rpm, so as to obtain the granules of the automobile foot pad material composition.

The formulations of examples 1-4 were sampled and tested for the same performance as the car foot mat material prepared in the comparative examples, and the results are shown in the table:

in the above table, the setting effect refers to the reset deformation effect of the product after the product is bent into an arc shape (particularly bending) or an L shape respectively, and is set by using a corresponding mold for 2 days, and the mold is removed and naturally stands for 2 hours.

When the initial state is completely recovered, the surface setting effect is 100%, and when the state after setting is completely maintained, the surface setting effect is 0%.

In the arc shape, the shaping effect of the foot pad is less than 25%, the foot pad has the capability of keeping the current situation after the arc-shaped deformation is finished, and the conditions that the foot pad is raised and the like after the foot pad is laid are avoided; in the L type, in order to guarantee that the foot pad can be detached and then laid for the second time after being laid, the reset function of the foot pad after the L type deformation is needed, namely, the more the foot pad can be restored to the original state after the L type deformation, the better the foot pad is.

The data and the experimental result are analyzed to obtain the result;

(1) The high-strength and large modulus of the high-density polyethylene are used, the toughness and flexibility of the high-density polyethylene can be improved by adding the linear low-density polyethylene with the mass content of 30%, and the obtained automobile foot pad is easy to bend under stress and convenient to lay.

(2) The polymer-based montmorillonite nano composite material compounded by the polymer and the montmorillonite after blending modification realizes the compounding of the polymer and the inorganic lamella on a nano scale because the polymer molecular chain is embedded between the inorganic lamella of the phyllosilicate and even leads the lamella to be stripped, thus leading the composite material to have excellent mechanical property, thermal property, rheological property, barrier property, optical property and the like.

(3) Through formula and process innovation, the general elasticity of the polymer is eliminated, so that the polymer has the same shaping capacity as an iron wire after being bent, a PE thick sheet (the thickness meets the requirement of an automobile foot pad and is generally about 6 mm) is prepared, the PE thick sheet is not easy to rebound after being bent like a wire or an iron wire, and shaping can be realized after the PE thick sheet is extruded or bent in a vertical extrusion direction and is bent forcibly.

(4) The surface of lignin is subjected to hydrophobic modification by vinyl silane, and S i-OH functional groups generated by hydrolysis of the vinyl silane form hydrogen bonds and covalent bonds with phenolic hydroxyl groups or carboxyl groups, and can perform polycondensation reaction with the hydroxyl groups or the carboxyl groups on the surface of powder under certain conditions, so that the surface property of the powder material is effectively changed, and the toughness of organosilane is retained. Introducing nonpolar high vinyl silane groups on the surface of lignin; the surface of the lignin is subjected to hydrophobic modification, so that the particle size is remarkably reduced and the particle uniformity is improved after the lignin is modified; meanwhile, the vinyl silane modified lignin plays a role of a nucleating agent in the HDPE matrix, is uniformly embedded into the HDPE matrix as a dispersed phase, and the interface is a continuous phase; and the brittle fracture surface of the composite material has a fault structure, lignin is agglomerated into hard particles, an HDPE resin continuous phase is blocked, the fracture surface of the concave-convex and hollow is presented, and the phase separation phenomenon exists;

(5) The dispersion of the lignin in the polymer resin can be improved by reducing the granularity of the lignin, the contact area of two-phase interfaces is increased, and the adhesion of the two phases is improved, so that the performance of the composite material is improved. The particle size of the lignin subjected to TEVS surface modification treatment is obviously reduced, the particle uniformity is obviously improved, and the dispersibility of the lignin in HDPE is improved.

(6) According to the melt impregnation process, discontinuous natural fibers are carded into a continuous state to prepare the natural fibers, meanwhile, due to the fact that the surfaces of the jute fibers are provided with the nonpolar functional groups, the jute fibers are hydrophobic, and the high-density polyethylene is poor in compatibility; the addition of the compatibilizer EVA-g-MAH realizes the improvement of the interface bonding strength of the resin matrix and the fiber.

(7) By adding the phosphogypsum/red mud, the particle size is refined, so that the dispersibility of the phosphogypsum/red mud in a matrix is improved, the compatibility with the matrix is improved, the defects are not easy to generate, the holes in the matrix are reduced, and the continuity of the matrix is improved; therefore, the bending strength and the bending modulus of the HDPE can be improved on the premise of keeping the tensile strength and the impact property of the material basically unchanged.

In the description herein, references to the description of "one embodiment," "an example," "a specific example," etc., mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

The preferred embodiments of the invention disclosed above are intended to be illustrative only. The preferred embodiments are not intended to be exhaustive or to limit the invention to the precise embodiments disclosed. Obviously, many modifications and variations are possible in light of the above teaching. The embodiments were chosen and described in order to best explain the principles of the invention and the practical application, to thereby enable others skilled in the art to best utilize the invention. The invention is limited only by the claims and their full scope and equivalents.

Claims

1. The utility model provides an easily design HDPE car callus on sole which characterized in that:

comprises 100 parts of main material and 25-35 parts of additive in parts by weight;

wherein the main body material comprises 60-80 parts of high-density polyethylene and 20-40 parts of linear low-density polyethylene;

wherein the additive comprises 10-15 parts of polymer-based montmorillonite nanocomposite, 2-10 parts of compatibilizer and 1-5 parts of antioxidant.

2. The easy-setting HDPE car foot pad according to claim 1, comprising 70 parts by weight of high density polyethylene, 30 parts by weight of linear low density polyethylene, 12 parts by weight of polymer-based montmorillonite nanocomposite, 6 parts by weight of compatibilizer and 2 parts by weight of antioxidant.

3. The easy-setting HDPE car foot pad according to claim 1, further comprising 0.5-1% by mass of the main body material of vinylsilane modified lignin.

4. The easily settable HDPE car foot pad according to any one of claims 1 to 3, further comprising long fibrilia in an amount of 5-10% by mass of the main body material.

5. The easy-to-shape HDPE (high-density polyethylene) automobile foot pad according to claim 4, characterized in that the easy-to-shape HDPE automobile foot pad further comprises phosphogypsum/red mud mixed powder which accounts for 3-8% of a main material, and the mass ratio of phosphogypsum to red mud in the phosphogypsum/red mud mixed powder is 3-10;

wherein the preparation of the phosphogypsum/red mud mixed powder comprises the following steps: uniformly mixing phosphogypsum and red mud according to a solid-water mass ratio of 1:1, adding deionized water, stirring, standing for 6 hours, filtering, and then drying at 100 ℃; and (3) crushing the obtained solid to obtain the phosphogypsum/red mud mixed powder with the particle size of 12-16 mu m after drying, and then placing the powder in a muffle furnace to dry for 4 hours at 250 ℃ for later use.

6. The easy-to-shape HDPE (high-density polyethylene) automobile foot pad according to claim 5, which is characterized by comprising 70 parts by weight of high-density polyethylene, 30 parts by weight of linear low-density polyethylene, 12 parts by weight of polymer-based montmorillonite nanocomposite, 6 parts by weight of compatibilizer, 2 parts by weight of antioxidant, 0.7 part by weight of vinylsilane modified lignin, 7 parts by weight of long hemp fiber and 5 parts by weight of phosphogypsum/red mud mixed powder.

7. The easily-shaped HDPE car foot pad according to claim 6, wherein the polymer-based montmorillonite nanocomposite is a polystyrene/montmorillonite nanocomposite, which adopts Gemini surfactant to enter montmorillonite layers through intercalation, effectively strip the montmorillonite layers, and prepare nano montmorillonite under ultrasonic conditions; then, solution blending is carried out on the organic modified montmorillonite and the polystyrene to prepare a polystyrene/organic modified montmorillonite composite material; drying and crushing the obtained polystyrene/organic modified montmorillonite composite material to obtain the polystyrene/montmorillonite nano composite material.

8. The easy-to-shape HDPE car foot pad according to claim 6, wherein the preparation of the long fibrilia comprises: opening the melting and dipping mould, enabling the continuous natural fiber strips to pass through between a plurality of pairs of lower dipping rollers and upper dipping roller pairs, and simultaneously extruding thermoplastic molten resin into the melting and dipping mould through an extruder connecting device to enable the thermoplastic resin melt to melt and dip the continuous natural fiber strips; and (3) allowing the impregnated continuous natural fiber strip to pass between an upper pressing roller and a lower pressing roller of a cooling and rolling device, and providing pressure by a pressing roller bullet to realize cooling of resin melt and secondary dispersion of natural fibers so as to obtain the continuous natural fiber prepreg.

9. The easy-setting HDPE car foot pad according to claim 6, wherein the preparation of the vinyl silane modified lignin comprises:

then weighing dry lignin powder, loading into a high-speed pulverizer, spraying vinyl silane hydrolysate on the surface of lignin in a spraying manner, continuously pulverizing at 25000r/min, mixing for 2min, taking out a sample, and drying at 105 ℃ for 2h to obtain the vinyl silane modified lignin.

10. The easy-to-shape HDPE automobile foot pad according to claim 6, wherein the preparation method of the automobile foot pad comprises the following steps:

stp1, weighing the raw materials in parts by weight;

stp2, adding high-density polyethylene, long fibrilia and linear low-density polyethylene into a high-speed mixer, stirring for 5min, adding the vinyl silane modified lignin, and continuously stirring for 1-2min;

stp3, then adding the polymer-based montmorillonite nanocomposite, the phosphogypsum/red mud mixed powder, the compatibilizer and the antioxidant, and continuing stirring for 7-10min;