CN115216243A - A kind of environment-friendly high-viscosity hot-melt adhesive film and preparation method thereof - Google Patents

Abstract

The invention discloses an environment-friendly high-viscosity hot-melt adhesive film and a preparation method thereof. Ethylene, butyl rubber, microcrystalline wax, and sodium stearate are added to the mixer, stirred evenly to obtain a sizing material; (2) the sizing material after mixing uniformly in step (1) is put into the twin-screw extruder. In the hopper, successively pass through the six heating zones of the twin-screw extruder, and fully plasticize by the screw extruder to obtain a molten composition; (3) extruding the molten composition obtained in step (2) through a die to obtain a molten composition; The film is cooled and shaped by a casting roll and a cooling roll to form the hot melt adhesive film. The hot-melt adhesive film prepared by the invention contains no solvent, has little pollution, and has good adhesion.

Description

A kind of environment-friendly high-viscosity hot-melt adhesive film and preparation method thereof

technical field

The invention relates to the technical field of hot-melt adhesive films, in particular to an environment-friendly high-viscosity hot-melt adhesive film and a preparation method thereof.

Background technique

Hot-melt adhesive, also known as hot-melt adhesive material, is a fusible adhesive. It does not require other solvents during the bonding process. It is solid at room temperature and is heated and melted into a liquid adhesive material. After wetting the adherend, after pressing and cooling, the bonding can be completed in a few seconds.

Hot-melt adhesive film is a kind of hot-melt adhesive. As a new type of adhesive, it is widely used because of its strong adhesive force, no pollution, convenient operation and easy storage. Hot melt adhesive films are generally prepared from saturated polyolefin materials, such as polyethylene (PE), ethylene-vinyl acetate copolymer (EVA), polyolefin elastomer (POE), etc. The preparation method is generally that the polyolefin material and the auxiliary agent are melt-blended and extruded and pelletized in a twin-screw extruder, and finally formed into a film in a film-making equipment. In order to increase the adhesive properties of hot melt adhesive films, additives that are conducive to bonding are usually added. However, most of the adhesives contain polar functional groups, such as ester functional groups, acid functional groups, ether functional groups and residual acidic substances, etc., which may release a large amount of toxic and harmful gases under high temperature conditions, which is not environmentally friendly.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide an environment-friendly high-viscosity hot-melt adhesive film and a preparation method thereof in view of the deficiencies in the prior art. The hot-melt adhesive film of the present invention contains no solvent, has little pollution, and has good adhesion.

For achieving the above object, the technical scheme provided by the present invention is:

An environment-friendly high-viscosity hot-melt adhesive film, comprising the following components:

40-60 parts by weight of low-density polyethylene grafted acrylic acid-2-hydroxyethyl ester copolymer,

30-50 parts by weight of amino acid modified maleic anhydride grafted polyethylene,

1-5 parts by weight of butyl rubber,

5-10 parts by weight of microcrystalline wax,

0.1-1.5 parts by weight of sodium stearate.

Further, the low-density polyethylene grafted acrylic acid-2-hydroxyethyl ester copolymer is prepared by the following method: under a nitrogen atmosphere, metered hydroxyethyl acrylate, AIBN and xylene are added to the reactor, stirred and dissolved , add low density polyethylene, accelerate stirring to make the reactants evenly mixed, swell on a rotary evaporator at 50 °C for 40 min, heat up to 80 °C and continue to react for 2.5 h, the product is extracted with acetone in a Soxhlet extractor for 12 h, Extracted with distilled water for 48 hours, and finally vacuum-dried at 60 °C to obtain low-density polyethylene grafted acrylic acid-2-hydroxyethyl ester copolymer.

Further, the mass ratio of the hydroxyethyl acrylate, the AIBN, the xylene, and the low density polyethylene is 4:0.3:8:100.

Further, the amino acid-modified maleic anhydride-grafted polyethylene is prepared by the following method: adding the amino acid and maleic anhydride-grafted polyethylene into a mixer in proportion to fully stir, at a rotational speed of 250 r/min, stirring for 10 min, and then transferring to a twin-screw Granulation takes place in an extruder.

Further, the mass ratio of the amino acid to the maleic anhydride grafted polyethylene is 2:100.

Further, the temperatures from the feed port to the die head of the twin-screw extruder are: 160°C, 170°C, 180°C, 190°C, 200°C, and 200°C, respectively, and the screw speed is 250 r/min.

The preparation method of the above-mentioned environment-friendly high-viscosity hot-melt adhesive film comprises the following steps:

(1) add low density polyethylene grafted acrylic acid-2-hydroxyethyl ester copolymer, amino acid modified maleic anhydride grafted polyethylene, butyl rubber, microcrystalline wax, sodium stearate into the mixer, 200 Under ℃, the rotating speed is 120r/min, and stirring for 30min, the rubber compound is obtained;

(2) Putting the sizing material after mixing uniformly in step (1) into the feeding hopper of the twin-screw extruder, passing through the six heating zones of the twin-screw extruder in turn, fully plasticized by the screw extruder, and obtaining melting combination;

(3) The molten composition obtained in step (2) is extruded through a die to obtain a molten film, which is cooled and shaped through a casting roll and a cooling roll to form the hot-melt adhesive film.

Further, in the six heating zones in the step (2), the temperature of the first heating zone is 160°C, the temperature of the second heating zone is 180°C, the temperature of the third heating zone is 180°C, and the temperature of the fourth heating zone is 180°C. The temperature is 190℃, the temperature of the fifth heating zone is 210℃; the temperature of the sixth heating zone is 220℃; the rotation speed of the screw is 150r/min;

Further, in the step (3), the temperature of the control die is 220°C, the temperature of the casting roll is 120-150°C, and the temperature of the cooling roll is 40-60°C.

Compared with the prior art, the beneficial effects of the present invention are:

1. The hot melt adhesive film of the present invention contains no solvent, has little pollution, and has good adhesion.

2. Polyethylene (PE) is one of the important general-purpose plastics, but PE is a non-polar polymer, with weak compatibility with inorganic substances and polar polymers, and poor adhesion. PE graft modification is a simple and effective functionalization method. The low density polyethylene of the present invention is grafted with acrylic acid-2-hydroxyethyl ester copolymer, and the graft polymer hardly changes the PE skeleton structure. Polar monomers with various functions are grafted to the main chain of PE, containing three functional groups of double bond, ester group and titanyl group, with high polymerization activity, which not only maintains the original characteristics of PE, but also improves the compatibility of PE.

3. Amino acid modified maleic anhydride grafted polyethylene, which is obtained by the reaction of amino acid and maleic anhydride grafted polyethylene, the modified polyolefin has the same density and melt index as the linear low density polyolefin resin similar to The use of this type of adhesive resin in coextruded structures can provide higher thermal stability than ethylene-vinyl acetate based adhesive resins.

4. The modified polyolefin and low-density polyethylene grafted acrylic acid-2-hydroxyethyl ester copolymer have good compatibility, and under the reconciliation of other components, they can better cross-link during bonding and compounding , so as to improve the bonding strength and make the product have better bonding performance.

Detailed ways

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the specific embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

Example 1

(1) Preparation of low-density polyethylene-grafted acrylic acid-2-hydroxyethyl ester copolymer: under nitrogen atmosphere, 4 parts by weight of hydroxyethyl acrylate, 0.3 parts by weight of AIBN and 8.5 parts by weight of xylene were added Into the reactor, stir and dissolve, add 100 parts by weight of low density polyethylene, accelerate stirring to make the reactants evenly mixed, swell on a rotary evaporator at 50 ° C for 40 min, heat up to 80 ° C and continue the reaction for 2.5 h, the product is Extraction with acetone for 12h in the extractor, followed by extraction with distilled water for 48h, and finally vacuum drying at 60°C to obtain low-density polyethylene grafted 2-hydroxyethyl acrylate copolymer.

Preparation of amino acid-modified maleic anhydride grafted polyethylene: add 2 parts by weight of amino acid and 100 parts by weight of maleic anhydride-grafted polyethylene into a mixer in proportion to fully stir, rotate at 250r/min, stir for 10min, and then transfer to a twin-screw The granulation is carried out in the extruder. The temperature from the feeding port of the twin-screw extruder to the die head is: 160°C, 170°C, 180°C, 190°C, 200°C, 200°C, and the screw speed is 250r/min.

(2) 50 parts by weight of low-density polyethylene grafted acrylic acid-2-hydroxyethyl copolymer, 40 parts by weight of amino acid modified maleic anhydride grafted polyethylene, 3 parts by weight of butyl rubber, 8 parts by weight The microcrystalline wax and 1 weight part of sodium stearate were added to the mixer, and at 200 ° C, the rotating speed was 120 r/min, and stirred for 30 min to obtain a rubber compound;

(3) put the rubber material into the feeding hopper of the twin-screw extruder, pass through the six heating zones of the twin-screw extruder in turn, the temperature of the first heating zone is 160°C, and the temperature of the second heating zone is 180°C , the temperature of the third heating zone is 180 ℃, the temperature of the fourth heating zone is 190 ℃, the temperature of the fifth heating zone is 210 ℃; the temperature of the sixth heating zone is 220 ℃; The extruder is fully plasticized to obtain a molten composition;

(4) The molten composition obtained in step (3) is extruded through a die to obtain a molten film, which is cooled and shaped by a casting roll and a cooling roll, wherein the temperature of the die is 220° C., and the temperature of the casting roll is 130° C. , the temperature of the cooling roll is 50°C, and the hot-melt adhesive film is formed.

Example 2

The difference from Example 1 is:

Low-density polyethylene grafted acrylic acid-2-hydroxyethyl ester copolymer is 60 parts by weight,

The amino acid modified maleic anhydride grafted polyethylene is 50 parts by weight,

Butyl rubber is 5 parts by weight,

Microcrystalline wax is 10 parts by weight,

Sodium stearate is 1.5 parts by weight.

The temperature of the die was 220°C, the temperature of the casting roll was 120°C, and the temperature of the cooling roll was 40°C.

Example 3

The difference from Example 1 is:

The low density polyethylene grafted acrylic acid-2-hydroxyethyl ester copolymer is 40 parts by weight,

The amino acid modified maleic anhydride grafted polyethylene is 30 parts by weight,

Butyl rubber is 1 part by weight,

Microcrystalline wax is 5 parts by weight,

Sodium stearate is 0.1 part by weight.

The temperature of the die was 220°C, the temperature of the casting roll was 150°C, and the temperature of the cooling roll was 60°C.

Comparative Example 1

Add 50 parts by weight of modified polyethylene, 40 parts by weight of maleic anhydride grafted polyethylene, 3 parts by weight of butyl rubber, 8 parts by weight of microcrystalline wax, 1 part by weight of sodium stearate into the mixer , at 200°C, with a rotating speed of 120 r/min, and stirring for 30 minutes to obtain a rubber compound; put the rubber compound into the feeding hopper of the twin-screw extruder, and pass through the six heating zones of the twin-screw extruder in turn. The first heating The temperature of the second heating zone is 160°C, the temperature of the second heating zone is 180°C, the temperature of the third heating zone is 180°C, the temperature of the fourth heating zone is 190°C, and the temperature of the fifth heating zone is 210°C; The temperature of the zone is 220°C; the rotation speed of the screw is 150r/min, fully plasticized by the screw extruder to obtain a molten composition; the molten composition is extruded through a die to obtain a molten film, which is cooled and shaped by a casting roll and a cooling roll. , wherein the temperature of the die head is 220° C., the temperature of the casting roll is 130° C., and the temperature of the cooling roller is 50° C. to form the hot-melt adhesive film.

Performance Testing

The hot melt adhesives prepared in Examples 1-3 and Comparative Example 1 were placed on a pressure molding machine to make samples with a thickness of about 120um, a length of 100mm, and a width of 25mm. Between 30mm TPO, press and iron in a constant temperature oven at 200°C, cool, and place for 24h for use. The T-type peel strength was measured at a speed of 100mm/min in a tensile testing machine, and the implementation standard was GB/T2791-1995. The test results are shown in Table 1.

Table 1

Based on the disclosure of the above description, those skilled in the art to which the present invention pertains can also make appropriate changes and modifications to the above-described embodiments. Therefore, the present invention is not limited to the specific embodiments disclosed and described above, and some modifications and changes to the present invention should also fall within the protection scope of the claims of the present invention.

Claims (9)

1. an environmentally friendly high-viscosity hot-melt adhesive film, is characterized in that: comprise the following components: 40-60 parts by weight of low-density polyethylene grafted acrylic acid-2-hydroxyethyl ester copolymer, 30-50 parts by weight of amino acid modified maleic anhydride grafted polyethylene, 1-5 parts by weight of butyl rubber, 5-10 parts by weight of microcrystalline wax, 0.1-1.5 parts by weight of sodium stearate. 2. The environment-friendly high-viscosity hot-melt adhesive film according to claim 1, wherein the low-density polyethylene-grafted acrylic acid-2-hydroxyethyl ester copolymer is prepared by the following method: under a nitrogen atmosphere, the Measured hydroxyethyl acrylate, AIBN and xylene were added to the reactor, stirred and dissolved, added low density polyethylene, accelerated stirring, mixed the reactants uniformly, swelled at 50°C for 40min on a rotary evaporator, and heated to 80°C The reaction was continued for 2.5 hours, the product was extracted with acetone in a Soxhlet extractor for 12 hours, then extracted with distilled water for 48 hours, and finally vacuum-dried at 60 °C to obtain low-density polyethylene grafted acrylic acid-2-hydroxyethyl acrylate copolymer. thing. 3. environment-friendly high-viscosity hot-melt adhesive film according to claim 2, is characterized in that: the mass ratio of described hydroxyethyl acrylate, described AIBN, described xylene, described low density polyethylene is 4: 0.3:8:100. 4. environment-friendly high-viscosity hot-melt adhesive film according to claim 1, is characterized in that: described amino acid-modified maleic anhydride grafted polyethylene is prepared by the following method: amino acid and maleic anhydride grafted polyethylene are The proportion is added to the mixer for full mixing, the rotation speed is 250r/min, and the mixture is stirred for 10min, and then transferred to the twin-screw extruder for granulation. 5. The environment-friendly high-viscosity hot-melt adhesive film according to claim 4, wherein the mass ratio of the amino acid to the maleic anhydride-grafted polyethylene is 2:100. 6. The environment-friendly high-viscosity hot-melt adhesive film according to claim 4, wherein the temperature from the feeding port of the twin-screw extruder to the die head is: 160°C, 170°C, 180°C, and 190°C, respectively. , 200 ℃, 200 ℃, the screw speed is 250r/min. 7. A preparation method of the environment-friendly high-viscosity hot-melt adhesive film according to any one of claims 1 to 6, characterized in that: comprising the steps: (1) add low density polyethylene grafted acrylic acid-2-hydroxyethyl ester copolymer, amino acid modified maleic anhydride grafted polyethylene, butyl rubber, microcrystalline wax, sodium stearate into the mixer, 200 Under ℃, the rotating speed is 120r/min, and stirring for 30min, the rubber compound is obtained; (2) Putting the sizing material after mixing uniformly in step (1) into the feeding hopper of the twin-screw extruder, passing through the six heating zones of the twin-screw extruder in turn, fully plasticized by the screw extruder, and obtaining melting combination; (3) The molten composition obtained in step (2) is extruded through a die to obtain a molten film, which is cooled and shaped through a casting roll and a cooling roll to form the hot-melt adhesive film. 8. The preparation method of the environment-friendly high-viscosity hot-melt adhesive film according to claim 7, characterized in that: in the step (2), in six heating zones, the temperature of the first heating zone is 160°C, and the temperature of the second heating zone is 160° C. The temperature of the zone is 180 ℃, the temperature of the third heating zone is 180 ℃, the temperature of the fourth heating zone is 190 ℃, the temperature of the fifth heating zone is 210 ℃; the temperature of the sixth heating zone is 220 ℃; the rotation speed of the screw is 150r/min. 9. The environment-friendly high-viscosity hot-melt adhesive film according to claim 7, wherein the temperature of the control die in the step (3) is 220°C, the temperature of the casting roll is 120-150°C, and the cooling The temperature of the rolls was 40-60°C.