阅读说明：本技术 Asa施胶剂及其制备方法、混合浆料和纸 (ASA sizing agent, preparation method thereof, mixed pulp and paper ) 是由 施晓旦 刘体霞 杨迪 于 2021-07-28 设计创作，主要内容包括：本发明公开了一种ASA施胶剂及其制备方法、混合浆料和纸。所述ASA施胶剂包括：ASA和乳化剂,所述乳化剂为溶液型阳离子淀粉的水溶液,所述ASA与所述溶液型阳离子淀粉的质量比为(2～8):1。本发明的ASA施胶剂制备过程中无需乳化剂的高温熬制糊化,操作简单、降低了危险性,同时ASA施胶剂用量少、成本低,成纸抗水性强。(The invention discloses an ASA sizing agent, a preparation method thereof, mixed pulp and paper. The ASA sizing agent comprises: the ASA emulsifying agent is a water solution of solution type cationic starch, and the mass ratio of the ASA to the solution type cationic starch is (2-8): 1. The preparation process of the ASA sizing agent does not need high-temperature boiling gelatinization of an emulsifier, is simple to operate, reduces the danger, and has the advantages of small dosage, low cost and strong water resistance of finished paper.)

1. An ASA sizing agent comprising: the ASA emulsifying agent is a water solution of solution type cationic starch, and the mass ratio of the ASA to the solution type cationic starch is (2-8): 1.

2. An ASA size according to claim 1 wherein the emulsifier has a pH of 2 to 6, preferably 3 to 5, such as 4;

and/or the concentration of the emulsifier is 2-20%, preferably 3-10%, for example 4%, wherein the percentages are mass percentages;

and/or the solution type cationic starch is the solution type cationic starch produced by Shanghai Dongyi New Material Co., Ltd and has the model number SCS16V 1.

3. An ASA size according to claim 1 wherein the mass ratio of the solution cationic starch to the ASA is (3-6: 1, such as 3.5:1 or 5.5: 1;

and/or the particle size D90 of the ASA sizing agent is less than or equal to 2.0 mu m, preferably D90 is less than or equal to 1.8 mu m.

4. A method for preparing an ASA sizing agent as set forth in any one of claims 1 to 3, comprising the steps of: and mixing and emulsifying the emulsifier and the ASA to obtain the ASA modified ASA.

5. The method of preparing an ASA size according to claim 4, wherein the emulsifying agent is preheated before being mixed and emulsified with the ASA.

6. The method of preparing an ASA sizing agent according to claim 5, wherein the temperature of the preheated emulsifier is 30 to 50 ℃, preferably 40 ℃.

7. A mixed size comprising the ASA sizing agent according to any one of claims 1 to 3.

8. The mixed slurry according to claim 7, further comprising 60 to 100% of paper pulp and 0 to 40% of papermaking filler, wherein the ASA sizing agent accounts for 4 to 14% of the total mass of the paper pulp and the papermaking filler, and the percentages are mass percentages;

and/or, the mixed slurry further comprises a retention aid and a drainage aid.

9. The mixing slurry according to claim 8, wherein the retention aid is polyacrylamide;

and/or the retention aid is added in an amount of 100 to 500ppm, such as 200ppm or 300ppm, wherein ppm is based on the total mass of the pulp and the papermaking filler;

and/or the filter aid is silica gel microparticles;

and/or the filter aid is added in an amount of 50 to 300ppm, such as 100ppm or 150ppm, wherein ppm is based on the total mass of the pulp and the papermaking filler.

10. A paper made using the mixed slurry of any one of claims 7 to 9.

Technical Field

The invention relates to an ASA sizing agent, a preparation method thereof, mixed pulp and paper

Background

With the continuous development of society, the consumption of paper in daily life of people is increasing day by day, and some papers are required to have good liquid resistance (particularly water and aqueous solution) so as to be suitable for writing or moisture resistance and humidity resistance. In order to achieve the above requirements, sizing treatment is performed during the paper making process or on the surface of the finished paper. The sizing method mainly comprises three methods of internal sizing, surface sizing and double sizing. Wherein, the internal sizing (internal sizing) is to add sizing material into the pulp in the paper making process and then to make paper or paperboard with lyophobic property.

Alkenyl succinic anhydride, ASA for short, is one of the reactive neutral sizing agents commonly used in the paper industry. Which is itself insoluble in water and is a non-ionic or weakly anionic species. At present, ASA is mainly used for gypsum mask paper, boxboard paper, liquid-bag paper and the like. The ASA serving as the internal sizing agent for the paper making pulp has higher reaction activity and retention rate, high curing speed and irreversible performance, and the dosage of the ASA is less than that of other internal sizing agents under the condition of achieving the same sizing degree. When the ASA is used as a sizing agent, an emulsifier is required to be added to enhance the ductility of the ASA, so that the waterproof effect is achieved. The conventional emulsifier is cationic starch, which needs to be decocted for gelatinization before use, so that the labor cost and the high-temperature steam cost of decocting the gelatin are increased, and the complexity and the danger of operation are increased in a high-temperature environment. Meanwhile, the water absorption of the sized paper needs to be further reduced, and although the dosage of ASA is smaller than that of other sizing agents in the pulp, the dosage of ASA has a further reduced space, so that the cost is reduced.

Therefore, there is a strong need for those skilled in the art to develop an ASA sizing agent that is easy to operate, cost effective, and further reduces the amount used.

Disclosure of Invention

The invention aims to solve the technical problems that the sizing agent in the prior art needs high-temperature boiling and pasting in the preparation process, so that the operation is complex and the danger is high, and the paper after sizing has high water absorption, large dosage of the sizing agent and high cost, and provides an ASA sizing agent, a preparation method thereof, mixed pulp and paper. The preparation process of the ASA sizing agent does not need high-temperature boiling gelatinization of an emulsifier, is simple to operate, reduces the danger, and has the advantages of small dosage, low cost and strong water resistance of finished paper.

The invention adopts the following technical scheme to solve the technical problems:

the invention provides an ASA sizing agent, which comprises: the ASA emulsifying agent is a water solution of solution type cationic starch, and the mass ratio of the ASA to the solution type cationic starch is (2-8): 1.

In the present invention, the pH of the emulsifier can be conventional in the art, preferably 2 to 6, more preferably 3 to 5, such as 4.

In the present invention, the preparation method of the emulsifier may be conventional in the art, and generally, the solution type cationic starch is dissolved in water and adjusted to the pH value with a pH adjuster.

Wherein, the pH regulator can be conventional in the field, and preferably is aluminum sulfate and/or citric acid.

In the present invention, the concentration of the emulsifier can be conventional in the art, and is generally 2 to 20%, preferably 3 to 10%, for example 4%, wherein the percentages are mass percentages.

The solution type cationic starch can be water-soluble cationic starch conventional in the art, and is preferably solution type cationic starch with model SCS16V1, which is produced by Shanghai Dongsheng New Material Co.

In the present invention, the mass ratio of the solution type cationic starch to the ASA is preferably (3-6): 1, for example, 3.5:1 or 5.5: 1.

The invention discloses a method for preparing an ASA sizing agent, which comprises the steps of using solution type cationic starch as a reinforcing agent and a retention aid in the papermaking industry, creatively using the solution type cationic starch as an emulsifier in the ASA sizing agent, not only omitting the conventional boiling and pasting process of the cationic starch, but also enabling the prepared ASA sizing agent to have smaller particle size and better water resistance of finished paper, saving the using amount of the ASA sizing agent and reducing the sizing cost.

In the present invention, the particle size of the ASA sizing agent may be as conventional in the art, preferably D90 ≦ 2.0 μm, more preferably D90 ≦ 1.8 μm.

The invention also provides a preparation method of the ASA sizing agent, which comprises the following steps: and mixing and emulsifying the emulsifier and the ASA to obtain the ASA modified ASA.

In the present invention, preferably, the emulsifier is preheated and then mixed with the ASA for emulsification.

Wherein, the temperature of the preheated emulsifier can be conventional in the field, preferably 30-50 ℃, and more preferably 40 ℃.

In the present invention, the emulsification operation is generally carried out in an emulsification apparatus. The emulsification apparatus may be conventional in the art, preferably an emulsification pump.

The invention also provides a mixed size which comprises the ASA sizing agent.

In the invention, the mixed slurry also comprises 60-100% of paper pulp and 0-40% of papermaking filler, wherein the ASA sizing agent accounts for 4-14% of the total mass of the paper pulp and the papermaking filler, and the percentages are mass percentages.

Wherein, the paper pulp can be conventional in the field, and can be one or more of wood pulp, straw pulp, hemp pulp, reed pulp, cane pulp, bamboo pulp and rag pulp, and wood pulp is preferred.

Wherein the papermaking filler may be conventional in the art and may generally be one or more of talc, china clay, calcium carbonate, titanium dioxide, calcined china clay, zeolite rock dust and attapulgite zircon.

In the present invention, preferably, the mixed slurry further includes a retention aid and a drainage aid.

Wherein the retention aid may be conventional in the art, and may typically be a polyacrylamide.

Wherein the retention aid may be added in an amount conventional in the art, preferably 100 to 500ppm, such as 200ppm or 300ppm, wherein ppm is based on the total mass of the pulp and the papermaking filler.

The filter aid can be conventional in the field, and can be silica gel microparticles generally.

Wherein the filter aid may be added in an amount conventional in the art, preferably from 50 to 300ppm, such as 100ppm or 150ppm, wherein ppm is based on the total mass of the pulp and the papermaking filler.

The invention also provides paper made of the mixed pulp.

On the basis of the common knowledge in the field, the above preferred conditions can be combined randomly to obtain the preferred embodiments of the invention.

The reagents and starting materials used in the present invention are commercially available.

The positive progress effects of the invention are as follows:

1. the paper made by the ASA sizing agent has stronger water absorption resistance of 70g/m²When the addition amount of the double-sided offset paper is 1.0Kg/t, the Cobb value of the front side can be averagely reduced to 23.5g/m²Even as low as 21.6g/m²(ii) a The Cobb value of the reverse side can be averagedReduced to 23.0g/m²Even as low as 21.0g/m²Compared with the prior sizing agent, the sizing agent can reduce by 15.3 percent.

2. When the water absorption value is equivalent to that of the prior art, the addition amount of the ASA sizing agent can be reduced by 20 percent;

3. the preparation method of the ASA sizing agent is simple, boiling and pasting are not needed, the labor cost of glue boiling and the cost of high-temperature steam can be saved, and the operation risk is reduced;

4. the ASA sizing agent has wide application range and can be used in the production process of cultural paper, white cardboard, kraft liner, cardboard paper and other paper types.

Detailed Description

The invention is further illustrated by the following examples, which are not intended to limit the scope of the invention. The experimental methods without specifying specific conditions in the following examples were selected according to the conventional methods and conditions, or according to the commercial instructions.

The solution type cationic starch of the embodiments 1 to 3 is produced by Shanghai Dongshi New Material Co., Ltd, and has the model of SCS16V 1;

the cationic starch of comparative example 1 was a type XW104, manufactured by Shandong Xilai starch Co., Ltd;

ASA is produced by camira chemical (shanghai) limited;

other raw materials are commercially available.

Example 1

S1: preparation of the emulsifier

Diluting the solution type cationic starch with warm water to 4%, adjusting pH to about 4.0 with citric acid, and heating to 40 deg.C to obtain emulsifier.

S2: preparation of sizing agent

And adding the emulsifier of S1 and ASA into an emulsification pump according to the volume ratio of 70:1 for emulsification to obtain the ASA sizing agent.

Example 2

S1 is the same as in example 1.

S2: preparation of sizing agent

And adding the emulsifier of S1 and the ASA stock solution into an emulsification pump according to the volume ratio of 100:1 for emulsification to obtain the ASA sizing agent.

Comparative example 1

Diluting the cationic starch to be emulsion with the concentration of 4% by using clear water under the stirring state, uniformly stirring, heating to 95 ℃, and preserving the heat at 95 ℃ for 15min to fully gelatinize the cationic starch. Cooling to room temperature after gelatinization, adjusting pH to about 4.0 with citric acid, and heating to 40 deg.C to obtain emulsifier.

And adding the obtained emulsifier and ASA into an emulsification pump according to the volume ratio of 100:1 for emulsification to obtain the ASA sizing agent.

Effect example 1

1. Particle size, solid content, viscosity and pH measurements

The ASA sizing agents of examples 1-2 and comparative example 1 were tested for particle size, solids content, viscosity and pH as follows:

particle size was measured using a Sichuan JL-1155 laser particle size distribution measuring apparatus, and the results are shown in Table 1;

the solid content was measured by a Mettler Toledo moisture meter, and the results are shown in Table 1;

the viscosity was measured using a Brookf IELDDV-II rotational viscometer, Bohler fly, with results shown in Table 1;

the pH was measured using a Metler FF model 28 acidimeter.

Effect example 2

1. Making paper by using paper

A paper machine system: the paper machine type is fourdrinier paper machine, the production speed is about 1200m/min, the papermaking width is 4960mm, and the production paper type is 70g/m²Double-sided offset paper.

Taking the ASA sizing agents obtained in the example 1 and the comparative example 1 as sizing agents in the sizing agent, the sizing amount is shown in the table 2, preparing mixed sizing agent, wherein the mixed sizing agent also comprises 200ppm of polyacrylamide and 100ppm of silica gel microparticles, and obtaining 70g/m through the steps of wire netting, papermaking and forming²Double-sided offset paper. Wherein, the sizing amount refers to the addition amount of the ASA sizing agent per ton of pulp and papermaking filler.

2. Water resistance test of finished paper

The water resistance of the finished paper is tested according to the standard GB/T1540-2003, and the specific method is as follows:

taking 5 paper patterns of the front and the back with a matched sampler; a weighed mass of the pattern is placed on the annular surface of the cylinder with the test surface facing upward, and the annular surface of the cylinder is tightly contacted with the pattern. Measuring 100mL of water by using a measuring cylinder, pouring the water into the cylinder, simultaneously starting a stopwatch for timing, pouring the water 10s-15s before the water absorption is finished, taking out a sample, enabling the water absorption surface of the sample to be upwards and stably placed on pre-paved water absorption paper, and immediately performing back-and-forth rolling once within 4s by using a metal press roller without applying other pressure to suck the residual water on the surface of the paper sample. The sample was quickly placed on a balance, and the mass after water absorption was weighed to determine the water absorption (cobb) value. The average water absorption (cobb) values of 2 to 5 sheets of paper samples measured in the same manner were calculated, and the results are shown in Table 2.

Effect example 3

1. Making paper by using paper

A paper machine system: the paper machine type is 3200m long-wire paper machine, the production speed is about 500m/min, and the production paper type is 330g/m²High bulk ivory board.

Taking the ASA sizing agents obtained in the example 2 and the comparative example 1 as sizing agents in the sizing agent, wherein the sizing amount is shown in the table 3, preparing mixed sizing agent, wherein the mixed sizing agent also comprises 200ppm of polyacrylamide and 100ppm of silica gel microparticles, and obtaining the white cardboard through the steps of wire netting, papermaking and forming. Wherein the sizing amount refers to the amount of ASA sizing agent added per ton of papermaking fiber.

2. Water resistance test of finished paper

The water resistance of the white cardboard was measured in the same manner as in effect example 2, and the results are shown in table 3.

TABLE 1 physical Properties test results for ASA sizing agents

Table 2 water resistance test results of the sized double coated papers

Table 3 water resistance test result table of white cardboard after sizing

As can be seen from Table 1, the solid content, pH value and viscosity value of the ASA sizing agent obtained in the examples 1-2 are basically equivalent to those of the comparative example 1; the particle size is significantly reduced compared to comparative example 1. The proportion of the particles within 1 μm and 2 μm is higher than that of the comparative example 1; the particle sizes of D50 and D90 were less than 0.85 μm and 1.8 μm, respectively, and were also less than comparative example 1, especially example 1. The smaller average particle size provides the example with the ASA size having a higher specific surface area and better ductility, which results in better water resistance of the sized paper.

As is apparent from Table 2, when the amount of the ASA sizing agent added in example 1 was 1.0Kg/t, the average Cobb values after the front and back sides were 23.5g/m, respectively²And 23.0g/m²When the amount of addition of the ASA sizing agent of example 1 was 0.8Kg/t, the average Cobb values after front and back aging were 23.8g/m, respectively, which were reduced by 14.5 and 12.9%, respectively, compared with comparative example 1²And 24.0g/m²Also, the average Cobb value was significantly lower than that of comparative example 1 when the amount was 1.0Kg/t, indicating that the amount of addition of the ASA sizing agent of example 1 could be reduced to 0.8Kg/t, which is more than 20% less than that of comparative example 1.

From Table 3 canIt was found that when the ASA sizing agent of example 2 was added at 1.5Kg/t, the average Cobb values after front and back curing were 79.8g/m, respectively²And 79.6g/m²Compared with comparative example 1, the reduction is respectively 12.4 percent and 11.9 percent; when the amount of the ASA sizing agent in example 2 added was 1.3Kg/t, the average Cobb values after surface maturation were 83.1g/m²And 82.7g/m²Also significantly lower than the average Cobb value at 1.5Kg/t added in comparative example 1; when the amount of the ASA sizing agent in example 2 added was 1.2Kg/t, the average Cobb values after surface maturation were 88.9g/m²And 89.7g/m²The average Cobb value satisfying the requirements and being smaller than that when the addition amount of the comparative example 1 is 1.5Kg/t shows that the addition amount of the ASA sizing agent of the example 2 on the white cardboard can be reduced to 1.2Kg/t, which is more than 20% less than that of the comparative example 1.