CN1161983A - Composition with self-controlling foam acrylic emulsion - Google Patents

Abstract

The invention provides a composition of acrylic acid emulsion with self-control foam capability, which is foamed by external mechanical strong stirring without agglutination, and the formed emulsion foam is uniform and fine, and can maintain the foam height for a certain time without external foam stabilizer. The acrylic emulsion composition is prepared by mixing a silicon compound grafted acrylic emulsion with proper components such as a filling agent, a tackifier, a coagulant, a wetting agent and the like, and can be applied to a non-woven foam back adhesive material.

Description

Composition with self-controlling foam acrylic emulsion

The present invention relates to compositions with self-controlling foaming acrylic emulsions (acrylic emulsions).

Organosiloxane compounds have the characteristics of low surface tension, lubricity, softness, wettability, and release properties, so they are often used to modify the surface properties of other molecular resins. The modification method is sometimes added, sometimes copolymerized, and sometimes grafted to achieve the purpose of surface modification.

Acrylic emulsion has many uses, and is widely used in coating resins, adhesives, inks and post-treatment agents for fibers. The acrylic emulsion is used in the back glue of the fabric, and its function is that when the non-woven fabric is cut, it will not take off the yarn. There are many kinds of adhesive materials (1) oily acrylic resin (2) water-based acrylic resin, which is generally called acrylic emulsion, (3) hot melt adhesive (4) non-woven fabric is directly made of low melting point fiber.

Coating method (1) Fully coated, the non-woven fabric is passed through the dipping tank, pressed dry, and dried. This process often results in an excess of impregnated resin, reducing the feel of the nonwoven. On the other hand, the gaps between fibers are filled with resin, resulting in airtightness. Although the function of adhesive material is achieved, it also causes quality degradation and loss of resin material. (2) Foam coating method, also known as dot coating , this method can not only achieve the dispersion of the adhesive material without causing the disadvantages of hand feeling drop and airtightness, but also the regional point dispersion can save consumables.

Generally, acrylic emulsion is used for dot-coated adhesives. During the coating process, it must be mechanically stirred vigorously to form a foam state. In order to maintain uniform and fine foam and a certain height of foam, the so-called stability, A foam stabilizer must be added. Most of the foam stabilizer is silicone oil or modified silicone oil. Although this foam stabilizer can maintain the foam height for a certain period of time, it has no foam reproducibility, that is, the foam fades over time. , and then vigorously stirred and foamed again, the foam height required for processing could not be recovered, that is, it became a foam suppression phenomenon. At the same time, the newly added silicone oil remains in the adhesive material, resulting in a decrease in adhesion.

In order to solve the shortcomings of the above-mentioned external foam stabilizer, the present invention utilizes the well-known technology of silicide-grafted acrylic emulsion, and uses a specific composition of silicide-grafted acrylic emulsion, through appropriate modulation of various additives, to complete the present invention "with self-control foam" Acrylic Emulsion Compositions".

The object of the present invention is to provide a kind of acrylic emulsion composition with self-controlling foam ability, the emulsion composition foams through mechanical strong stirring, no coagulation phenomenon occurs, the formed emulsion foam is in a uniform and fine state, and can maintain The foam height for a certain period of time has the ability to reproduce, which means that after the foam disappears or the foam height drops, the original result can also be obtained by vigorously stirring and foaming again.

The acrylic emulsion composition is a silicide-grafted acrylic emulsion formulated with appropriate additives, tackifiers, coagulants, wetting agents and the like, and can be applied to non-woven foam adhesive materials.

For general acrylic emulsion, after being stirred at a high speed of 500-10,000rpm by a specific stirring blade or a butterfly stirring plate for 10 seconds to 10 minutes, the emulsion will show a height several times higher than the original emulsion, and the density of different foams. Latex After stirring and foaming, depending on the mechanical stability, some latex will coagulate and gel immediately and cannot be used. However, after foaming, general latex will gradually burst/defoam and recover with the passage of time. At the same time, the foam Usually the size is different. In the case of adding silicone polymer [such as silicone oil (Silicone oil)], the foam size is relatively uniform, but due to the presence of silicone oil, it often affects the properties of latex, such as adhesion.

In order to overcome the inhomogeneity and instability of the above-mentioned foam, the present invention directly grafts a specific and quantitative organosilicon compound on the acrylic emulsion of a specific composition, and prepares an acrylic emulsion with self-controlling foam ability through the preparation of appropriate additives. combination.

It is well known that organosilicon compound grafted acrylic emulsion can achieve the purpose of improving properties: USP4,987,180, USP4,985,155 for fiber softness and elasticity modification, Japanese Patent Ping 3-227312 for stability, room temperature bridging; Japanese Patent Ping 3-227313 Solution polymerized inorganic material binder; EP0,350,240 hardened coatings, paints; Japanese Patent No. 63-227670, USP3,575,910, USP3,294,725 lubricity, release, water-repellent coatings, etc.

The organosilicon compound grafted acrylic acid emulsion used in the present invention, wherein the organosilicon compound is a siloxane compound containing vinyl end groups or propylene end groups, such as S710 (Dow Corning), and the grafting amount is 0.3 to 3.0 wt%. ~1.5wt% is suitable, the grafted acrylic emulsion has a solid content of 40~50wt%, emulsified particle size: 120~180nm, glass transition temperature, Tg: -10℃~10℃, it is an emulsion resin with a specific composition . The organic silicon compound content accounts for about 0.5-5.0 wt% of the solid content of the acrylic emulsion.

The filler that uses is calcium carbonate or silicon dioxide, and the calcium carbonate that the present invention uses has three kinds of particle diameters: NS-400, NS-1000, and SS-30, and adding method has: (1) calcium carbonate is processed into paste in advance , and then added to the emulsion for mixing, (2) Calcium carbonate was directly added to the emulsion for mixing. In the former, the calcium carbonate is pre-ground into a 40-60wt% paste with a mixer or a ball mill. The particle size of the calcium carbonate is NS-1000. ratio), (40-60phr means that the mixing weight ratio of organosilicon compound grafted acrylic acid emulsion and filler is 100:40-60.), and 50phr is appropriate.

Viscosifiers can use polyvinyl alcohol (PVA), hydroxypropyl cellulose, hydroxybutyl cellulose, methyl cellulose acetate, or butyl cellulose acetate, such as: BP-5 lion mucus, BP-20 and BP-24E (vinyl polyvinyl alcohol PVA), hydroxypropyl cellulose HPC (10%), the results show that HPC is better than BP-5, BP-20, and BP-24E in foam stabilization effect, and will not cause calcium carbonate For the phenomenon of precipitation, the amount of tackifier used is 1-6phr, and 3-4phr is appropriate.

The coagulant can use 30wt% ammonia water or an aqueous solution containing 2-6 carbon amine groups. If 30wt% ammonia water is used, the usage amount is 0.8phr-1.6phr, preferably 1.2-1.4phr.

Wetting agent can make the emulsion composition increase the wettability of the object to be coated. The wetting agent used in the present invention is polyethylene glycol (PEG) with a molecular weight of 200-1000, preferably 400-600. Its use The amount is 4-12phr, and 6-8phr is suitable.

In order to make the above-mentioned and other purposes, features, and advantages of the present invention more clearly understandable, some preferred embodiments are enumerated below, and in conjunction with the attached table, the detailed description is as follows: Embodiment 1

The polymerization preparation of acrylic acid silicon compound grafted acrylic acid emulsion of the present invention, as general acrylic resin emulsion synthetic device, 1, stirrer Japanese-made DC-RT type, four mouth type reaction tank 4L, pyrex glass device, heater, temperature controller, heat Sensor (Sensor), cooling pipe, nitrogen. The reaction components are prepared according to A, B, C, D, E, respectively, and then added to the reaction tank one by one according to the reaction time. This reaction adopts the redox method, and the reaction time is about 320 minutes. The temperature is controlled within 45°C-50°C, and the stirring speed is 160-280rpm. Table (1) is A, B, C, D, E pre-preparation solution, A is the pre-emulsification pre-preparation solution, B is the pH regulator, C, D, E are the starter. The total content is about 2427 grams, and the solid content is 1092 grams (45%). S-710 is about 10.3 g of the organic silicon compound (1%) of the solid content. The reaction sequence is shown in Table (2). "Example 2, 3, 4"

Synthetic composition formulation, and synthesis steps are as in Example 1, but wherein the amount of S-710 is changed from 10.3g to 5.1g, 30.9g, 51.5g, and its amount accounts for about 0.5%, 3%, and 5% of the solid content. .

The organosilicon compound grafted acrylic acid emulsion of above-mentioned embodiment 1-4 gained respectively gets 100phr, adds tackifying agent (HPC10%) 3.6phr, filler (pretreatment ball-milled calcium carbonate 55%) 53phr respectively, coagulant (ammonia 30% ) 1.4phr, humectant (polyethylene glycol) 6phr. "Comparative Example 1"

The formula and synthesis steps of the synthetic composition are as in Example 1, but wherein the amount of S-710 is 0 (not added), and the obtained acrylic emulsion is respectively added with a tackifier, a filler, and a coagulant according to the steps of Examples 2, 3, and 4. , and stirred evenly into an acrylic emulsion, the acrylic emulsion obtained in the above (embodiments 1-4) and (comparative example 1) was strongly stirred by a specific stirring blade, and the results were shown in table (3) at 4500rpm for 2 minutes.

              Table (1) Synthetic Composition Formula Component No. Composition Components Addition Amount (g) Solid Content

DS-4(10%) 153.3 15.33

NP-6 17.5 17.5A NP-9 17.5 17.5 Pre-DI-H ₂ O 518 Dairy chain transfer agent 1.6 1.6 Kl I-acid 10.3 10.3 2-HEMA 31 31

MAN 6.2 6.2

                                                                   

BA 103 103

Table (1) Synthetic composition formula (continued) Ingredient number Composition ingredients Addition amount (g) Solid content

EA 770 770

S-710 10.3 10.3B HOAC(10%) 7   -

DI-H ₂ O 2.87-C AP 2.52 2.52

DH ₂ O 70 -D t-BHP 1.0 1.0

DI-H ₂ O 70-E SFS 2.66 2.66

DI-H ₂ O 245 -

Table (1) Synthetic composition formula ingredient number Composition ingredients Added amount (g) Solid content - Total amount 2427g 1092g

Table (2) Synthetic step time (minutes) Step Adding order 0 0 Start the machine, component B enters the reaction tank, stir and N ₂ purge 15 1 (A) 100g add (C, D) 3.8g each 160rpm

(E) 12.8g45 2 2 (A) 100g (C, D) 4.5g each 160rpm

(E) 15g75 3 3 (A) 150g (C, D) 5.7g each 160rpm

(E)19.2g105 4 4 (A)200g (C, D) 7.6g each 180rpm

(E)25.6g

Table (2) Synthesis steps (continued) Time (minutes) Steps Addition order 135 5 5 (A) 200g (C, D) each 7.6g 200 rpm

  (E) 25.6g165 6   (A) 200g (C, D) 7.6g each 220 rpm

(E)25.6g195 7 7 (A)250g(C,D)9.5g 240 rpm

  (E) 32g225             (A) 250g add (C, D) 9.5g 260 rpm

(E)32g255

                                                                                                                     

Table (3) Comparative Example 1-5 and Comparative Example 1 Foaming Results Test No. Example 1 Example 2 Example 3 Example 4 Comparative Example 1S-710 in the original acrylic 1% 0.5% 3% 5% 0% acrylic acid Emulsion content Foaming ratio 3.5 3.5 3.5 3.85 3 Foam homogeneity Fine and uniform Fine and uniform Fine and uniform Fine and uniform Defoaming rate after 3hrs No defoaming No defoaming No defoaming 0 hr % 30% 11% 100% Calcium Carbonate Slight Slight 1/10 All Medium Precipitation after 10hrs

Although the present invention is disclosed above with some preferred embodiments, it is not intended to limit the present invention. Anyone who is familiar with the technology can make some changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection of the present invention The scope should be defined by the claims appended hereto.

Claims (11)

1, a kind of acrylic emulsion composition with self-control foam ability, is applicable to as the foam adhesive material of non-woven fabric, it comprises: (1) Grafted acrylic emulsion of an organosilicon compound containing vinyl or propenyl end groups, the grafting amount of the organosilicon compound in the emulsion is 0.1 to 3 weight percent, the solid content is 40 to 50 weight percent, and the emulsified particle diameter is 120 to 180nm, Tg is -10°C to 10°C; (2) filler, about 40 to 60 percent of the content of the organosilicon compound-grafted acrylic emulsion; (3) tackifier, about 1 to 6 percent of the content of the acrylic emulsion grafted with the organosilicon compound; (4) coagulant, about 0.8 to 1.6 percent of the content of the organosilicon compound-grafted acrylic emulsion and (5) Wetting agent, about 4 to 12 percent of the content of the organosilicon compound-grafted acrylic emulsion. 2. The composition of claim 1, wherein the organosilicon compound accounts for 0.5 to 5% by weight of the solid content of the acrylic emulsion. 3. The composition of claim 1, wherein the filler comprises 50 percent of the silicone compound-grafted acrylic emulsion. 4. The composition as claimed in claim 1, wherein the filler is calcium carbonate or silicon dioxide pretreated into a paste of 40 to 60% by weight. 5. The composition of claim 1, wherein the tackifier comprises 3 to 4 percent of the organosilicon compound-grafted acrylic emulsion. 6. The composition of claim 1, wherein the tackifier is polyvinyl alcohol, hydroxypropyl cellulose, hydroxybutyl cellulose, methyl cellulose acetate, or butyl cellulose acetate. 7. The composition of claim 1, wherein the coagulant comprises 1.2 to 1.4 percent of the silicone compound-grafted acrylic emulsion. 8. The composition of claim 1, wherein the coagulant is ammonia water, or an amine-based aqueous solution containing 2 carbons to 6 carbons. 9. The composition of claim 1, wherein the wetting agent comprises 6 to 8 percent of the silicone compound grafted acrylic emulsion. 10. The composition of claim 1, wherein the humectant is polyethylene glycol. 11. The composition of claim 10, wherein the polyethylene glycol has a molecular weight of about 200 to 1000.