Conductive hot-melt pressure-sensitive adhesive applied to anti-static floor and preparation method of conductive hot-melt pressure-sensitive adhesive

Abstract

The invention discloses a conductive hot-melt pressure-sensitive adhesive applied to an anti-static floor and a preparation method thereof.The conductive hot-melt pressure-sensitive adhesive is prepared from, by mass, 20% of conductive medium mixture and 80% of base stock, the base stock is prepared from, by mass, 20%-40% of polymer, 20%-40% of tackifier, 10%-25% of plasticizer and 3%-10% of anti-aging agent, the conductive medium mixture comprises 0.5% of carbon fiber, 0.3% of sodium hexametaphosphate, 0.2% of white sugar and 19% of a base material. According to the conductive hot-melt pressure-sensitive adhesive, sodium hexametaphosphate and white sugar are creatively compounded as a combined dispersant, and the carbon fibers can be uniformly dispersed in the conductive hot-melt pressure-sensitive adhesive through the synergistic effect of the combined dispersant and the carbon fibers, so that the conductive hot-melt pressure-sensitive adhesive has excellent conductivity.

Description

Technical Field

[0001] The invention relates to a conductive hot-melt pressure-sensitive adhesive used for anti-static flooring and a preparation method thereof. Background Art

[0002] With the development of the electronics industry, polyvinyl chloride (PVC) anti-static flooring has been widely used to meet the anti-static needs of production workshops and other places such as electronic product assembly and testing. When installing this PVC anti-static flooring, it is necessary to apply water-based anti-static glue to the ground before installing the anti-static flooring. This construction method is inefficient and environmentally unfriendly. The water-based anti-static glue will volatilize toxic and harmful gases. To solve the problem of harmful gas volatilization, existing PVC anti-static flooring will be coated with hot-melt pressure-sensitive adhesive (a non-flowing adhesive layer at room temperature with adhesion) on the floor installation surface. During installation, it is necessary to pre-attach a criss-cross copper foil mesh to the ground. The main function of the copper foil mesh is to better enhance conductivity, connect underground pre-buried conductors, and allow static electricity generated by the floor to enter the ground, making the floor free of static ions. However, commercially available hot-melt pressure-sensitive adhesives are non-conductive because it is very difficult to add a conductive medium during the preparation process. The conductive medium is prone to uneven dispersion in the hot-melt pressure-sensitive adhesive, which may cause the hot-melt pressure-sensitive adhesive to be partially conductive or completely non-conductive. Summary of the Invention

[0003] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, the present invention provides a conductive hot-melt pressure-sensitive adhesive for anti-static flooring and a preparation method thereof.

[0004] In order to solve the above-mentioned technical problems, the present invention adopts the following technical solutions:

[0005] A conductive hot-melt pressure-sensitive adhesive for anti-static flooring comprises the following raw materials, calculated by mass percentage: 20% of a conductive medium mixture and 80% of a base material, wherein the base material comprises 20-40% of a polymer, 20-40% of a tackifier, 10-25% of a plasticizer, and 3-10% of an antioxidant; and the conductive medium mixture comprises 0.5% of carbon fiber, 0.3% of sodium hexametaphosphate, 0.2% of white sugar, and 19% of the base material.

[0006] Preferably, the polymer is one or more of SBS, SiS, and EVA.

[0007] Preferably, the tackifier is one or more of terpene resin, rosin modified resin, and C5 hydrogenated petroleum resin.

[0008] Preferably, the plasticizer is naphthenic oil or paraffin oil.

[0009] Preferably, the antioxidant is tert-butylhydroquinone.

[0010] The method for preparing the conductive hot-melt pressure-sensitive adhesive for anti-static flooring comprises the following steps:

[0011] (1) Preparation of the combined dispersant: Sodium hexametaphosphate and sugar were mixed uniformly at a mass ratio of 3:2;

[0012] (2) Preparation of conductive medium mixture: put the combined dispersant, carbon fiber, and a portion of the base material into a kneader and mix them uniformly at 140°C;

[0013] (3) The conductive medium mixture and the remaining base material are put into a stirring kettle, and a spiral ribbon stirring blade is used at a speed of 70 rpm to heat and melt the mixture. The temperature is raised to 140° C. After all the mixture is evenly melted, the mixture is discharged and cooled to obtain a conductive hot melt pressure sensitive adhesive.

[0014] The beneficial effects of the present invention are:

[0015] The present application creatively compounds sodium hexametaphosphate and white sugar as a combined dispersant. Through the synergistic effect of the combined dispersant and carbon fiber, the carbon fiber can be evenly dispersed in the conductive hot melt pressure-sensitive adhesive, thereby giving the conductive hot melt pressure-sensitive adhesive excellent conductive properties. DETAILED DESCRIPTION

[0016] To make the objectives, technical solutions, and advantages of the present invention more clearly understood, the present invention is described below by way of specific embodiments. However, it should be understood that these descriptions are merely illustrative and are not intended to limit the scope of the present invention. In addition, in the following description, descriptions of well-known structures and technologies are omitted to avoid unnecessary confusion of the present invention.

[0017] Experimental formula of Example 1

[0018]

[0019]

[0020] Example 1 Preparation method (taking 100 kg as an example to illustrate the design concept of this application):

[0021] (1) Preparation of the combined dispersant: 0.3 kg of sodium hexametaphosphate and 0.2 kg of sugar were mixed evenly;

[0022] (2) Preparation of a conductive medium mixture: The combined dispersant prepared in step (1), 0.5 kg of carbon fiber, and 19 kg of base material were placed in a kneader and mixed uniformly at 140° C.;

[0023] (3) The conductive medium mixture and the remaining 80 kg of base material are put into a stirring kettle, and a spiral ribbon stirring blade is used at a speed of 70 rpm to heat and melt. The temperature is raised to 140° C. After all the mixture is evenly melted, the material is discharged and cooled to obtain a conductive hot melt pressure sensitive adhesive.

[0024] The base materials mentioned above are EVA, SiS, C5 hydrogenated petroleum resin, rosin modified resin, naphthenic oil, and tert-butylhydroquinone;

[0025] Test performance: The performance indicators of the above conductive hot melt pressure sensitive adhesive were tested according to the method specified in "Polyvinyl chloride plastic floor adhesive" (JCT550-2019). The test data of the conductive hot melt pressure sensitive adhesive prepared in Example 1 are as follows:

[0026] Table 2 Physical properties

[0027] project Industry Standards Actual measured value 90° peel strength / ((N / mm)) ≥1.0 1.2 Shear strength / MPa ≥0.3 0.5 Resistance / Ω <![CDATA[≤3×10 5 ]]> <![CDATA[4×10 4 ]]>

[0028] From the above data, it can be seen that the 90° peel strength of the conductive hot melt pressure sensitive adhesive prepared in Example 1 is 1.2 N / mm, the shear strength is 0.5 MPa, and the resistance is 4×10 4 Ω; the above values ​​are in line with the performance requirements of the industry standard for conductive hot melt pressure sensitive adhesives.

[0029] Table 3 Comparative Example 1 and Comparative Example 2

[0030]

[0031]

[0032] In Comparative Example 2, sodium hexametaphosphate was not added, and the carbon fibers were obviously unevenly dispersed. The carbon fibers in the colloid were clumps visible to the naked eye. In Comparative Example 1, white sugar was not added, and the carbon fibers tended to be uniform. However, after coating, the conductive performance data was tested and found that one of the 17 groups failed the test. The average resistance of the remaining 16 groups was between 2.5×10 5 Ω.

[0033] The present application creatively compounds sodium hexametaphosphate and white sugar as a combined dispersant. Through the synergistic effect of the combined dispersant and carbon fiber, the carbon fiber can be evenly dispersed in the conductive hot melt pressure-sensitive adhesive, thereby giving the conductive hot melt pressure-sensitive adhesive excellent conductive properties.

[0034] Although the present invention has been described in detail with reference to the above embodiments, it will be apparent to those skilled in the art from this disclosure that various changes or modifications may be made to the present invention without departing from the principles and spirit of the invention as defined in the claims. Therefore, the detailed description of the disclosed embodiments is intended to be illustrative only and not to limit the present invention, which is to be defined by the claims.

Claims

1. A conductive hot melt pressure sensitive adhesive for anti-static flooring, characterized in that: Calculated by mass percentage, the raw materials include: 20% conductive medium mixture and 80% base material, the base material includes 20-40% polymer, 20-40% tackifier, 10-25% plasticizer, and 3-10% antioxidant, the conductive medium mixture includes 0.5% carbon fiber, 0.3% sodium hexametaphosphate, 0.2% white sugar, and 19% base material.

2. The conductive hot melt pressure sensitive adhesive for anti-static flooring according to claim 1, characterized in that: The polymer is one or more of SBS, SiS and EVA.

3. The conductive hot melt pressure sensitive adhesive for anti-static flooring according to claim 1, characterized in that: The tackifier is one or more of terpene resin, rosin modified resin and C5 hydrogenated petroleum resin.

4. The conductive hot melt pressure sensitive adhesive for anti-static flooring according to claim 1, characterized in that: The plasticizer is naphthenic oil or paraffin oil.

5. The conductive hot melt pressure sensitive adhesive for anti-static flooring according to claim 1, characterized in that: The antioxidant is tert-butylhydroquinone.

6. A method for preparing a conductive hot melt pressure sensitive adhesive for anti-static flooring according to claim 1, characterized in that: The following steps are involved: (1) Preparation of the combined dispersant: Sodium hexametaphosphate and sugar were mixed uniformly at a mass ratio of 3:2; (2) Preparation of conductive medium mixture: put the combined dispersant, carbon fiber, and a portion of the base material into a kneader and mix them uniformly at 140°C; (3) The conductive medium mixture and the remaining base material are put into a stirring kettle, and a spiral ribbon stirring blade is used at a speed of 70 rpm to heat and melt the mixture. The temperature is raised to 140° C. After all the mixture is evenly melted, the mixture is discharged and cooled to obtain a conductive hot melt pressure sensitive adhesive.

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