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Pressure Sensitive Adhesive Tape Preparation Method

S1, first take the biodegradable extract of the sensitive adhesive resin  30% 72%, biodegradable oligomer polyfunctional degree 1. 0% , crosslinking agent 0. 22% 6% 2% and thermal initiator or light initiator  0. 2% 2% , just the right amount of water or solvent, mix and stir 1  5 hours;

S2. Then, the biodegradable base film is wound on a raw material frame 310, and the transparent plastic film is wound on another raw material frame 310, and both are bypassed at the bottom of composite roll 321. The biodegradable base film and transparent plastic thin film are pressed together through composite roll 321, and then stretched to the receiving frame 410 for winding;

S3. Then pour the mixed non-silicon pressure-sensitive glue in S1 into storage bucket 100 in the tape preparation device, and cover the bucket cover 102 and gas storage box 210;

S4, then start the pumping motor 220 and drive impeller 221 to rotate to the gas storage box 210 to supplement and compress the air, because the glue in the storage bucket 100 is released, the top of the bucket will be produced negative pressure, by releasing the air in the gas storage box 210 into the storage bucket 100, in order to adjust the internal pressure of the bucket, so that the glue can continue to release. And help to control the speed and amount of glue release;

S5, start the receiving motor 420 rewinding the biodegradable base film and transparent plastic film, at the same time release the non-silicon pressure-sensitive glue in the storage bucket 100 and fall into the two films, and then extruded the glue between the two films to form a non-silicon pressure sensitive adhesive tape;

S6. Then start the servo motor 233 to drive the CAM 232 to rotate every 10 degrees to release the air in the gas storage box 210 into the material storage barrel 100 to relieve the negative pressure;

S7, to be coated with glue film conveying to drying box 600, changed early start drying device 630 half line of the infrared lamp, 631 to 10  drying temperature of 100 ℃, and the other half infrared tubes from 631 to 100  curing temperature 200 ℃, within the after drying box 600 on membrane drying glue curing;

S8. Until the drying and curing non-silicon pressure-sensitive adhesive glue film are recoiled on the receiving rack 410, remove the non-silicon pressure-sensitive adhesive tape after rewinding.

Acrylic pressure sensitive adhesive has been widely used in product packaging, printing, medical and health industries, among which solvent acrylate pressure sensitive adhesive because of its good adhesion and pressure sensitive, excellent corrosion resistance and aging resistance, set many advantages in one and in the acrylic pressure sensitive adhesive industry occupies an important position.

However, currently commonly used solvent-based acrylic pressure sensitive adhesive has the problem of initial viscosity and holding viscosity can not be both, high initial viscosity of acrylic pressure sensitive adhesive its holding viscosity is poor, and high holding viscosity of acrylic pressure sensitive adhesive its initial viscosity is weak, thus limiting the use of acrylic pressure sensitive adhesive range and service life.

Moreover, the molecular weight of the solvent – based acrylate pressure sensitive adhesive synthesized at present is low. Molecular weight is one of the main factors affecting the properties of acrylic pressure sensitive adhesive. However, the increase of molecular weight will make the viscosity of polymer solution rise, especially in the polymerization process, the increase of viscosity will cause the heat of polymerization reaction is not easy to lose, resulting in detonation.

Therefore, generally through free radical polymerization in solution synthesis of acrylate molecular weight are relatively small, which is related to the polymerization solvent, polymerization process, etc. The chain transfer coefficients of the monomers synthesized acrylate pressure sensitive adhesive were different in different solvents, which led to the significant effects of solvents on the polymerization reaction rate, chain termination rate, polymer viscosity, molecular weight and distribution.

In addition, it is difficult to control the reaction process of solvent-based acrylate pressure sensitive adhesive in the synthesis process, which will result in its low conversion rate and poor performance. As a result, polymerization process also becomes an important factor affecting the pressure sensitive property of acrylate. Therefore, a solvent – based acrylic pressure sensitive adhesive with initial adhesion, stripping and retention is needed.

Polylactic acid (PLA) is an important biodegradable polymer material. Polylactic acid (PLA) is made from corn or potato starch as the basic raw material. It is biodegradable to produce carbon dioxide and water in nature, so it is a kind of green and environment-friendly material. Polylactic acid has similar mechanical strength and processing properties as polyolefin. However, its shortcomings such as poor gas barrier, poor heat resistance, high brittleness, slow crystallization rate, and low crystallinity limit its further application. In particular, polylactic acid has the disadvantages of poor toughness and non-conductivity, so it can not be used in the field of pressure-sensitive adhesive which needs conductive properties.

Therefore, it is necessary to modify polylactic acids, such as blending, copolymerization, and nanocomposite, in order to meet the required properties of bio-based polyurethane pressure-sensitive adhesive. In order to solve the above problems, we invented a bio-based polyurethane pressure-sensitive adhesive with good electrical conductivity and mechanical properties.

Preparation involves the following steps:

Step 1: Take sodium oleate-modified calcium sulfate whisker dissolved in ethyl acetate, stir to get calcium sulfate whisker dispersion; Molybdenum-disulfide grafted chlorosilane was dissolved in ethyl acetate and stirred to obtain molybdenum-disulfide dispersion solution. Polyol poly (lactic acid) (PLA) dissolved in butanone, adding calcium sulfate whisker dispersion, mos2 dispersion, stir evenly, add dicyclohexyl carbon 2 imide, under 40-60 ℃ the nitrogen protection, adding diisocyanate, organic bismuth catalyst, in 50 -heating reaction 4 -6 h under 80 ℃, obtain the dimer; Adding neutralizing agent triethylamine, reaction 5 -20 min; the chain extender diethanolamine is dissolved in water to obtain diethanolamine solution, adding the diethanolamine solution, stirring, so that the polymer emulsification form emulsion, distillation of acetone in the emulsion to obtain biobased polyurethane glue;

Step 2: apply biological base polyurethane adhesive, more and more methyl phenyl isocyanate, dimethyl cyclohexylamine, surfactant AEO-3, antioxidant 1010, 326, ultraviolet absorbent UV-stir 3 -4 h, filtration, biological base polyurethane pressure sensitive adhesive.

The film made of polyacrylate latex has good properties of time, phase aging, jet oil, and acid-base, and it has good adhesion properties for fiber, leather, paper, and so on. Therefore, latex is widely used in coating, fabric, and tanning. In the application of fabric, it is mainly used as a printing and dyeing adhesive, fabric coating agent, wakeup agent, anti-pilling agent, adhesive for non-woven products, etc.

Water-based acrylic copolymerization latex development through non-crosslinking, diplomatic, and white crosslinking three stages, but these crosslinking conditions are relatively high, the need for high temperature (about 160℃) and low pH value, not only a waste of resources, but also increase the damage to the processing of the substrate, and the application process also released harmful to human body formaldehyde substances.

To implement water-based acrylic ester copolymer latex crosslinking at low temperatures, some people use the method of external catalyst: using a mixture of magnesium chloride hexahydrate and citric acid (volume ratio 1: 1), such as Azcat A catalyst as a two-component low-temperature curing adhesive, but the main shortcomings are used with catalyst, more trouble, and configuration stability, the residual pulp can not be reused. Another approach is to use radiation-induced crosslinking technology, but this requires additional specialized equipment, at a relatively high cost. Reactive epoxides have been introduced by reacting with epichlorohydrin to replace the formaldehyde-releasing substance N hydroxymethyl acrylamide, but the problem with this technique is that AOX pollution is added to the environment.

The technical problem to be solved is to overcome the above shortcomings and design a kind of macromolecule with a special structure and its preparation method so that the formed latex main body has a certain degree of pre-crosslinked network structure but a nonlinear macromolecule. The invention provides a preparation method for an environmentally friendly low-temperature water-based acrylate copolymerization adhesive. The method is to introduce a certain degree of crosslinking into macromolecules in the polymerization process by adding crosslinking components containing two or more of two diethers into the poly monomer to participate in the copolymerization.

A low-odor and high-strength acrylic structural adhesive comprise A component and B component,

A component comprises Armour hydroxyl ethyl acrylate, 1, 3 butyl glycol, methyl acrylate, methyl acrylate, ABS resin, SBS resin, polyurethane resin, triphenylphosphine, N, N  2 hydroxyethyl toluidine, propyl glycidyl ether oxygen preparation silane, four sodium ethylenediamine tetraacetic acid, methyl hydroquinone, wax powder;

B component includes polyether polyol, plasticizer, benzoyl peroxide, epoxy resin, and wax powder. The weight ratio of each component of component A is as follows: 5 ~ 20 hydroxyl ethyl methacrylate, 1, 3 butyl glycol dimethyl acrylate 15 ~ 30, methyl acrylic acid 5 ~ 20, ABS resin 5 ~ 15, 5 ~ 15 SBS resin, polyurethane resin 15 ~ 30, triphenylphosphine 0. 1 ~ 1. 0, N, N  2 hydroxyethyl of toluidine 0. 1 ~ 1 .0, glycidyl ether oxy propyl trimethoxysilane 0.1 ~ 1.0, tetrasodium ethylenediamine tetraacetate 0.1 ~ 1.0, o-methyl hydroquinone 0.1 ~ 1.0, wax powder 1 ~ 5.

The weight ratio of each component of component B is as follows: polyether polyol 50 ~ 150 parts, plasticizer 5 ~ 30 parts, peroxidized benzoyl 1.5 ~ 10 parts, epoxy resin 15 ~ 200 parts, wax powder 1 ~ 5 parts. Benzoate is preferred as the plasticizer.

The invention relates to A preparation method of low-odor and high-strength acrylic structural adhesive. The preparation method of component A is carried out in accordance with the following steps:

Step 1: According to the following weight of get 5 ~ 20 hydroxyl ethyl methacrylate, 1, 3 butyl glycol dimethyl allyl methacrylate acid ester 15 ~ 30, 5 ~ 20 5 ~ 15, ABS resin, SBS resin 5 ~ 15 to join in the reaction kettle, rising at a rate of about 1 ℃ / min to 75 ℃, 60   to stir 1 3 hours;

Step 2: according to the following weight of 15 to 30 for polyurethane resin, triphenylphosphine 0. 1 ~ 1. 0, N, N  2 hydroxyethyl of toluidine 0. 1 ~ 1. 0 to join to complete the steps in a reaction kettle, maintain 60  the temperature of 75 ℃, keep stirring 50 minutes, stop stirring, cooled to room temperature.

Step 3: In accordance with the following weight parts, 0.1 ~ 1.0 parts of glyceryl ether oxy-propyl trimethoxysilane, 0.1 ~ 1.0 parts of tetrasodium ethylenediamine tetraacetate, 0.1 ~ 1.0 parts of o-methyl hydroquinone, and 1 ~ 5 parts of wax powder are added to the reaction kettle completed in step 2.

While stirring and dispersing, at the same time vacuuming, A component is obtained; B component preparation methods according to the following steps:

Step 1: according to the following weight obtain 50 ~ 150 polyether polyols, plasticizer 5 ~ 30, 15-200 epoxy resin, and wax powder 1 ~ 5 to join the first reaction kettle, rising at a rate of about 1 ℃ / min to 30  50 ℃, fully mixing 1 small, cool to room temperature;

Step 2: Obtain 1. 5-10 parts of benzoyl peroxide according to the following weights. Add them to the first reaction kettle after Step 1, stir for 30 minutes, and vacuum while stirring and dispersing to obtain the B component. According to the above preparation method, the following embodiments are generated: The weight ratio of each component of Embodiment 1, Component A, is 5 hydroxy ethyl methacrylate, 1, 3 butyl glycol dimethyl methacrylate acrylic ester 15, 5 copies of five copies, ABS resin, SBS resin May 15, polyurethane resin, triphenylphosphine 0. 1, N, N  2 hydroxyethyl of toluidine 0. 1, propyl glycidyl ether oxygen preparation silane 0 1 part, 0.1 part tetrasodium ethylenediamine tetraacetic acid, 0.1 part o-methyl hydroquinone, 1 part wax powder. B component weight ratio of each component is polyether polyol 50 parts, plasticizer 5 parts, benzoyl peroxide 1.5 parts, epoxy resin 15 parts, wax powder 1 part.