CN115748307A

CN115748307A - Laminated foam sheet molding green packaging material and preparation method thereof

Info

Publication number: CN115748307A
Application number: CN202211479898.6A
Authority: CN
Inventors: 唐婷婷; 贺磊; 沈国栋; 张裕福; 苟青; 肖迪; 袁佑铭; 林海; 刘桂龙; 朱旺平
Original assignee: China Haisum Engineering Co Ltd
Current assignee: China Haisum Engineering Co Ltd
Priority date: 2022-11-24
Filing date: 2022-11-24
Publication date: 2023-03-07

Abstract

The invention discloses a laminated foam sheet molding green packaging material and a preparation method thereof. The preparation method comprises the following steps: mixing and dispersing wood pulp and an adhesive with film-forming property, adding a foaming agent for foaming, and adding a foam stabilizer for continuous foaming to obtain surface layer foam slurry; then mixing and dispersing the wood pulp fiber, the fiber reinforced composite material and the elastic adhesive, and obtaining the core layer foam slurry by the same method; and extruding and spraying the surface layer foam slurry onto a forming net, and drying to obtain the thin surface layer forming material. And extruding and spraying the core layer foam slurry onto the surface layer molding material for several times, and drying to obtain the composite molding material. And finally, extruding and spraying the surface layer foam slurry on the composite molding material, and drying to obtain the final composite molding material. The concentration of the fiber in the foam slurry is 1-5%, which is far higher than the concentration of the fiber produced by the common papermaking, so that the water consumption is greatly reduced; the method of the invention is improved on the basis of the traditional papermaking mode, reduces the equipment investment and saves the cost.

Description

Laminated foam sheet molding green packaging material and preparation method thereof

Technical Field

The invention relates to a laminated foam sheet molding green packaging material and a preparation method thereof, belonging to the technical field of papermaking.

Background

With the rise and development of the packaging industry, the packaging materials with the buffering and shockproof functions are subjected to foam plastics, pulp molding materials and fiber foaming packaging materials in sequence. The foamed plastic has the advantages of light weight, easy processing, good protective performance, wide applicability, low cost and the like, but the foamed plastic is difficult to recycle after being discarded, pollutes the environment by burning and has poor environmental protection performance. With the gradual recognition of the low-carbon economy and green packaging concepts, the development technology of environment-friendly packaging materials is increasingly emphasized.

The foam forming technology is different from the traditional wet and dry forming technology, adopts foam as a carrier to bear fibers, enables the fibers to be well dispersed in water-based foam, and enables the fibers to be finally deposited on a net part by controlling the breakage of the foam so as to form a novel paper sheet forming technology of one or more layers of paper sheets. The forming technique can effectively reduce water consumption and energy consumption, and can prevent fiber flocculation, thereby producing paper or paperboard with excellent properties (such as evenness and bulk).

CN101787217B discloses a plant fiber foaming cushion packaging material and a manufacturing method thereof, wherein the material is uniformly mixed and then is injected into a mold, a slurry system is foamed and expanded under the action of a special foaming agent, and the cushion packaging material is obtained after demolding and drying, and is naturally degradable, low in cost and excellent in cushion performance. CN104312182B discloses a degradable foamed packaging material and a preparation method thereof, wherein the degradable foamed packaging material is obtained by performing superfine treatment on fibers, modifying a plant fiber composite base material, foaming, extruding, cooling and shaping. CN102977625B discloses a plant fiber foaming packaging plate and a processing technology thereof, wherein the plant fiber and an auxiliary agent are mixed, and the finished product is obtained through four processes of vacuum suction filtration, microwave foaming and hot air drying. The finished products are formed by the die, so that industrial production is difficult to realize, and the finished products are difficult to take out of the die, so that the utilization rate of the finished products is reduced.

Disclosure of Invention

The purpose of the invention is: aiming at the problems and defects of the prior art for preparing the foaming packaging plate by mould forming, the invention provides a laminated foam sheet forming green packaging material and a preparation method thereof.

In order to achieve the purpose, the invention provides a preparation method of a laminated foam sheet forming green packaging material, which is characterized by comprising the following steps:

step 1): mixing and dispersing wood pulp fibers and an adhesive with film-forming property, adding a foaming agent for foaming, and adding a foam stabilizer for continuous foaming to obtain surface layer foam slurry;

step 2): mixing and dispersing wood pulp fibers, fiber reinforced composite materials and elastic adhesives according to a certain proportion, adding a foaming agent for foaming, and adding a foam stabilizer for continuous foaming to obtain core layer foam slurry;

and step 3): extruding and spraying the surface layer foam slurry onto a forming net, and drying until the solid content of the slurry is 0-60 wt% to obtain a thin surface layer forming material;

step 4): extruding and spraying the core layer foam slurry onto the surface layer forming material for several times, and drying until the solid content of the slurry is 0-60 wt% to obtain a composite forming material;

and step 5): and extruding and spraying the surface layer foam slurry onto the composite molding material, and drying to obtain the final composite molding material.

Preferably, the wood pulp fibers in the step 1) are at least one of hardwood pulp fibers and softwood pulp fibers; the addition of the wood pulp fiber is 1-5 wt% of the surface layer foam slurry.

Preferably, the fiber reinforced composite material in the step 2) is at least one of carbon fiber, basalt fiber and silicon carbide fiber; the addition amount of the wood pulp fiber and the fiber reinforced composite material is 1 to 5 weight percent of the mass of the foam slurry of the core layer respectively.

Preferably, the adhesive with film-forming property in the step 1) is at least one of polyacrylamide, polyethylene oxide, polyvinyl alcohol, carboxymethyl cellulose, guar gum, fatty alcohol-polyoxyethylene ether, alkylphenol polyoxyethylene ether and the like; the elastic adhesive in the step 2) is at least one of polyurethane rubber, styrene butadiene rubber and epoxy resin.

Preferably, the foaming agent in step 1) and step 2) is at least one of sodium dodecyl sulfate K12, sodium fatty alcohol-polyoxyethylene ether sulfate AES and rosin soap foaming agent.

Preferably, the foam stabilizer in step 1) and step 2) is at least one of dodecyl dimethyl amine oxide, alkyl alcohol amide and silicone polyether emulsion.

Preferably, the drying manner in steps 3) to 5) is vacuum drying or infrared drying.

The invention also provides a green packaging material prepared by the preparation method of the laminated foam sheet molding green packaging material. The thickness of the pressure-resistant layer is 10-100 mm, and the pressure-resistant range is 0.5-5 bar.

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

according to the laminated foam sheet molding green packaging material and the preparation method thereof, the concentration of fibers in the foam slurry is 1% -5%, which is far higher than that of common papermaking, so that the water consumption is greatly reduced; the core layer foam slurry is sprayed on the primary core layer forming material for a plurality of times, so that the thickness of the material can be effectively increased; the core layer adopts high-elasticity modulus fiber and high-elasticity adhesive, so that the elasticity modulus of the material is increased; the surface layer adopts an adhesive with good film-forming property, so that the film-forming property of the material surface is improved; the improvement on the traditional papermaking mode reduces the equipment investment and saves the cost.

Drawings

FIG. 1 is a process flow diagram for preparing a laminated foam sheet molded green packaging material provided by the present invention;

FIG. 2 is a photograph of a real object of the material prepared in example 1;

fig. 3 is a photograph of a cross section of the material prepared in example 1.

Detailed Description

In order to make the invention more comprehensible, preferred embodiments are described in detail below with reference to the accompanying drawings.

The agents used in the examples of the present invention were purchased from national pharmaceutical reagents unless otherwise specified and were not further processed.

The percentages stated in the present invention are, unless otherwise specified, percentages by weight.

Example 1

A method for preparing a laminated foam sheet molding green packaging material is shown in figure 1, and comprises the following steps:

adopting a sulfate softwood bleached pulp board of Mo Banggao Sen paper making company, taking the absolute dry 4%, adding 10% absolute dry PVA217, then respectively adding 3.00% absolute dry guar gum, adding water, defibering at the rotating speed of 2000 rpm for 20min, after defibering and dispersing uniformly, adding 2g/L absolute dry sodium dodecyl sulfate, foaming at the rotating speed of 300-500 rpm, and adding 2g/L dodecyl dimethyl amine oxide for stabilizing the foam for 10min to obtain the surface layer foam slurry. And spraying the surface layer foam slurry onto a forming net for forming, and drying by infrared ray assistance until the solid content of the slurry is 0wt% to obtain the surface layer forming material.

Adopting a Mo Banggao forest paper making company sulfate needle wood bleached pulp board, taking 3% of absolute dry, taking 1% of absolute dry carbon fiber of a Switzerland company, adding 10% of absolute dry polyurethane and water, defibering at 2000 rpm for 20min, after defibering and dispersing uniformly, adding 2g/L of absolute dry sodium dodecyl sulfate, foaming at 300-500 rpm, adding 2g/L of dodecyl dimethyl amine oxide for stabilizing foam for 10min, and obtaining the core layer foam slurry. And spraying the core layer foam slurry to the surface layer forming material for forming, and drying by infrared ray assistance until the solid content of the slurry is 0wt% to obtain the one-step composite forming material.

And spraying the surface layer foam slurry onto the primary composite molding material for molding, and performing infrared ray assisted drying to obtain a final composite molding finished product. The actual picture and the sectional view are shown in fig. 2 and fig. 3, respectively.

Example 2

This example differs from example 1 in that guar was not added.

Example 3

This example differs from example 1 in that the sheet material was dried to 20wt% of the solids content of the slurry.

Example 4

This example is different from example 1 in that the core layer foam slurry was sprayed 3 times to the skin layer forming material to be formed.

The materials prepared in examples 1-4 were tested for performance. The test results are shown in table 1:

TABLE 1 test results of Material Properties

	Thickness/mm	Withstand voltage/bar
			Example 1	25	0.85
Example 2	25	0.72
			Example 3	30	1.10
Example 4	70	3.06

While the invention has been described with respect to a number of embodiments, it will be understood by those skilled in the art that the foregoing and other changes, omissions and deviations in the form and detail thereof may be made without departing from the scope of this invention.

Claims

1. The preparation method of the laminated foam sheet molding green packaging material is characterized by comprising the following steps of:

step 3): extruding and spraying the surface layer foam slurry onto a forming net, and drying until the solid content of the slurry is 0-60 wt% to obtain a thin surface layer forming material;

step 5): and extruding and spraying the surface layer foam slurry on the composite molding material, and drying to obtain the final composite molding material.

2. The method of producing a laminated foam sheet-formed green packaging material as claimed in claim 1, wherein the wood pulp fibers in the step 1) are at least one of hardwood pulp fibers and softwood pulp fibers; the addition of the wood pulp fiber is 1-5 wt% of the surface layer foam slurry.

3. The method of producing a laminated foam sheet-formed green packaging material of claim 1, wherein the fiber-reinforced composite material of step 2) is at least one of carbon fiber, basalt fiber and silicon carbide fiber; the addition amount of the wood pulp fiber and the fiber reinforced composite material is 1 to 5 weight percent of the mass of the foam slurry of the core layer respectively.

4. The method for preparing a laminated foam sheet-formed green packaging material according to claim 1, wherein the adhesive having film-forming property in step 1) is at least one of polyacrylamide, polyethylene oxide, polyvinyl alcohol, carboxymethyl cellulose, guar gum, fatty alcohol-polyoxyethylene ether, alkylphenol polyoxyethylene ether, etc.; the elastic adhesive in the step 2) is at least one of polyurethane rubber, styrene butadiene rubber and epoxy resin.

5. The method for preparing a laminated foam sheet-formed green packaging material according to claim 1, wherein the foaming agent in the step 1) and the step 2) is at least one of sodium dodecyl sulfate K12, sodium fatty alcohol polyoxyethylene ether sulfate AES and rosin soap foaming agent.

6. The method for preparing a laminated foam sheet-formed green packaging material according to claim 1, wherein the foam stabilizer in step 1) and step 2) is at least one of dodecyldimethylamine oxide, alkylolamide and silicone polyether emulsion.

7. The method for preparing a laminated foam sheet-formed green packaging material according to claim 1, wherein the drying in steps 3) to 5) is performed by vacuum drying or infrared drying.

8. A green packaging material produced by the method of producing a laminated foam sheet-formed green packaging material according to any one of claims 1 to 7.