A papermaking process using organically modified fillers

Abstract

The present invention relates to the field of papermaking, and particularly relates to a papermaking process using an organically modified filler, which includes: First step, weigh the organically modified filler, and after being brewed and diluted in sequence, mix it into a pulp pool and mix it evenly with the pulp; Second step, after screening the pulp mixed in the first step, introduce it into a paper machine, and after flowing the pulp, forming, dewatering, drying and winding, obtain paper containing the organically modified filler; wherein, the organically modified filler is pectin aluminum @ boron-containing palygorskite powder. The present invention prepares an organically modified filler, applies the organically modified filler to the papermaking process, finally improves the strength of the paper, and at the same time, the organically modified filler does not contain toxic chemical pollutants, which is more in line with the concept of environmental protection chemical industry.

Description

Technical Field

[0001] The present invention relates to the field of papermaking, and particularly to a papermaking process using an organically modified filler. Background Art

[0002] At present, the fillers used in the papermaking industry are mainly divided into inorganic minerals such as ground calcium carbonate (GCC), precipitated calcium carbonate (PCC), talc powder, titanium dioxide, kaolin, etc. Papermaking fillers are the largest proportion part in the paper stock except for fibers, which can replace a large amount of pulp fibers, and their addition amount can account for 20% - 40% of the paper stock components.

[0003] The purpose of adding fillers is to improve the whiteness, opacity and smoothness of the paper sheet, improve the printing adaptability, reduce costs, and endow the paper with special properties such as flame retardancy, wear resistance, heat insulation, etc. However, most of the fillers used by current papermaking enterprises are inorganic mineral fillers. The differences in the structural form and physical and chemical properties between the fillers and the pulp will reduce the bonding between fibers, have an adverse impact on the paper and the papermaking process, cause the paper strength to decline, and increase the load and operating cost of the wastewater treatment system. In recent years, organically modified fillers are gradually replacing inorganic mineral fillers. However, the current organically modified fillers on the market not only have limited strengthening effect on the paper, but also produce a large amount of toxic chemical pollutants. Summary of the Invention

[0004] Aiming at the problems existing in the prior art, the purpose of the present invention is to provide an organically modified filler that can enhance the paper properties and is green and pollution-free, and its application in the papermaking process.

[0005] The purpose of the present invention is achieved by the following technical solutions:

[0006] A papermaking process using an organically modified filler, comprising:

[0007] In the first step, after weighing the organically modified filler, it is brewed and diluted and then mixed into the pulp pool and evenly mixed with the pulp;

[0008] In the second step, after sieving the pulp mixed in the first step, it is introduced into a papermaking machine, and after flowing, forming, dewatering, drying and rewinding, a paper sheet containing the organically modified filler is obtained;

[0009] Wherein, the organically modified filler is pectin aluminum @ boron-containing palygorskite powder.

[0010] Preferably, in the first step, after the organically modified filler is brewed and diluted with pure water, an organically modified filler solution with a mass concentration of 20% - 30% is formed.

[0011] Preferably, in the first step, the organically modified filler is 8% - 16% of the absolute dry pulp mass.

[0012] Preferably, after the organically modified filler is mixed into the pulp tank in the first step, a PPE wet strength agent is further added, and the addition amount of the PPE wet strength agent is 0.52%-0.85% of the mass of the absolutely dry pulp.

[0013] Preferably, in the first step, the concentration of the pulp in the pulp tank is 10%-20%, the pulp is a plant fiber slurry, and the raw materials of the plant fiber include at least one of softwood, hardwood, and grass plants.

[0014] More preferably, the softwood includes at least one of larch, Korean pine, masson pine, Yunnan pine, and Mongolian pine; the hardwood includes at least one of poplar, birch, and eucalyptus; the grass plants include at least one of reed, bamboo, wheat straw, rice straw, Chinese alpine rush, and sorghum stalk.

[0015] More preferably, the plant fibers in the pulp include larch fibers, poplar fibers, and wheat straw in a mass ratio of 5-7:2-4:1.

[0016] Preferably, in the second step, the sieving is through a 200-mesh sieve; the dehydration is carried out under vacuum conditions, and the humidity after dehydration is 30%-50%; the drying is carried out at 55-80°C, and the humidity after drying is 3%-5%.

[0017] Preferably, in the second step, after the mixed pulp is sieved, it is introduced into a paper machine together with a sizing agent. The sizing agent is alkyl ketene dimer or alkenyl succinic anhydride, and the addition amount of the sizing agent is 1%-3% of the mass of the absolutely dry pulp.

[0018] Preferably, the basis weight of the paper containing the organically modified filler prepared in the second step is 35-45 g / m 2 .

[0019] Preferably, the preparation process of the organically modified filler includes:

[0020] (1) Treating palygorskite powder in a sodium hydroxide solution to obtain activated palygorskite powder;

[0021] (2) Participating the activated palygorskite powder in the reaction of diphenyldihydroxy silane and boric acid, and then through sintering treatment to obtain boron-containing modified palygorskite;

[0022] (3) Adding a solution containing aluminum ions to the boron-containing modified palygorskite, fully mixing, and then dropwise adding a pectin solution to control the pH of the reaction, and obtaining pectin aluminum@boron-containing palygorskite powder after the reaction.

[0023] More preferably, the process of the first step of preparing the organically modified filler includes:

[0024] Weigh palygorskite powder and mix it with sodium hydroxide solution. Under ultrasonic action, a uniform mixed solution is formed. Then, raise the temperature to 50 - 60 °C and stir for 3 - 5 h to obtain activated palygorskite powder;

[0025] Among them, the particle size of palygorskite powder is 20 - 50 μm; the molar concentration of sodium hydroxide solution is 0.5 mol / L, and the mass ratio of palygorskite powder to sodium hydroxide solution is 1:10 - 20.

[0026] More preferably, the process of step (2) for preparing the organic modified filler includes:

[0027] S1. Weigh diphenyldihydroxysilane, activated palygorskite powder and xylene and place them in a reaction flask. Heat up to 125 °C. After stirring evenly, gradually add boric acid, and then heat up to 145 - 150 °C and stir and react for 8 - 12 h. Remove the generated water at any time, then remove xylene, continue to heat up to 340 - 380 °C and keep the temperature for 1 - 2 h. After the reaction is completed, cool to room temperature to obtain palygorskite encapsulated by polyborosiloxane;

[0028] Among them, the mass ratio of diphenyldihydroxysilane, activated palygorskite powder, boric acid to xylene is 0.13 - 0.26:2 - 4:0.03 - 0.06:20 - 40;

[0029] S2. Place the palygorskite encapsulated by polyborosiloxane in a muffle furnace for sintering. The sintering temperature is 550 - 600 °C. After keeping the temperature for 2 - 4 h, obtain boron - containing modified palygorskite.

[0030] More preferably, the process of step (3) for preparing the organic modified filler includes:

[0031] S3. Weigh boron - containing modified palygorskite and mix it with deionized water. Under ultrasonic conditions, a uniform mixed solution is formed. Then, under stirring conditions, continuously add aluminum chloride solution. After the addition is completed, continue to stir for 15 - 30 min to form an aluminum - containing mixed solution;

[0032] Among them, the mass fraction of aluminum chloride solution is 1.5% - 3%; the mass ratio of boron - containing modified palygorskite, aluminum chloride solution to deionized water is 1:5 - 8:10 - 20;

[0033] S4. First, weigh a small amount of sodium hexametaphosphate and dissolve it in deionized water, and then gradually and slowly add pectin and stir to form a uniform solution, namely pectin solution;

[0034] Among them, the degree of esterification of pectin is 10% - 25%, and the viscosity - average molecular weight is 15000 - 25000; the mass ratio of sodium hexametaphosphate, pectin to deionized water is 0.3 - 0.6:0.5 - 5:100;

[0035] S5. Add the pectin solution drop by drop into the aluminum-containing mixture, continuously stir during this period, and at the same time control the pH of the reaction solution to be 6 - 6.5. After the pectin solution is completely added, stir for 10 - 20 min, adjust the pH of the reaction solution to 7 - 7.5, continue to stir for 30 - 60 min, and then through precipitation, centrifugation, washing, suction filtration and drying, aluminum pectinate @ boron-containing palygorskite powder is obtained;

[0036] Among them, the mass ratio of the pectin solution to the aluminum-containing mixture is 1 - 3:1.

[0037] The beneficial effects of the present invention are as follows:

[0038] 1. The present invention prepares an organically modified filler and applies the organically modified filler to the papermaking process, ultimately improving the strength of the paper. At the same time, the organically modified filler does not contain toxic chemical pollutants, which is more in line with the concept of environmental protection chemistry.

[0039] 2. The organically modified filler prepared by the present invention is aluminum pectinate @ boron-containing palygorskite powder, which is in-situ synthesized on the basis of palygorskite powder. Palygorskite powder has a large specific surface area and strong adsorption performance. It has good dispersibility in water, showing good colloidal properties and adsorption capacity. However, it will quickly disintegrate when soaked in water, and the binding force with pulp fibers is also insufficient, which becomes a defect restricting its application in paper. The palygorskite powder modified by the present invention not only retains certain adsorption and dispersibility, but also solves the defect of easy disintegration and the performance enhancement of the paper.

[0040] 3. When sintering polyborosiloxane-coated palygorskite, the sintering temperature cannot be set too high or too low. Too high will cause the internal structure of palygorskite to be damaged and affect its performance, and too low will cause polyborosiloxane not to be decomposed. The present invention sets the sintering temperature at 550 - 600 °C. This temperature can not only reach the decomposition temperature of polyborosiloxane, but also keep the structure of palygorskite from collapsing. During this process, polyborosiloxane decomposes into a network structure containing boron elements and is loaded on palygorskite. This process makes the surface of palygorskite rich in dynamic chemical bonds formed by silicon-oxygen-boron bonds (Si-O-B) and boron-oxygen-boron bonds (B-O-B), with higher stability, greatly slowing down the disintegration degree of palygorskite in water.

[0041] 4. In addition, it is found in the preparation process of the present invention that during the formation of the complex coating of pectin, the usage amount of aluminum ions can be greatly reduced. It is speculated that the reason may be that since the surface of palygorskite contains rich boron elements, and boron elements have a certain binding property with pectin and can crosslink to form a network structure. Aluminum ions themselves have a certain degradation effect on cellulose, and too many aluminum ions are not conducive to the storage of paper, which also improves the stability of the paper from another aspect. Detailed implementation mode

[0042] To more clearly illustrate the present invention and gain a clearer understanding of its technical features, objectives, and beneficial effects, the following detailed description of the technical solution of the present invention is provided, but it should not be construed as a limitation on the scope of implementation of the present invention.

[0043] Regarding the preparation process of the organically modified filler of the present invention, the analysis is as follows: (1) First, palygorskite is treated with sodium hydroxide alkaline solution to form a porous structure by removing some of its solvents. During this process, the surface of palygorskite is also activated, thus obtaining activated palygorskite powder; (2) By using the reaction of diphenyldihydroxysilane and boric acid, polyborosiloxane is generated to coat palygorskite; then it is sintered at high temperature to decompose the polyborosiloxane, forming a cross-linked network structure containing boron elements to coat the surface of palygorskite; (3) First, an aluminum ion solution is mixed with boron-modified palygorskite to adsorb aluminum inside and on the surface of the boron-modified palygorskite, and then the dropping of pectin solution is controlled to gradually form a pectin-aluminum complex to coat the surface of the boron-modified palygorskite, finally obtaining pectin-aluminum@boron-containing palygorskite powder.

[0044] The following further describes the present invention in conjunction with the following embodiments.

[0045] Example 1

[0046] A papermaking process using an organically modified filler includes:

[0047] In the first step, after weighing the organically modified filler pectin-aluminum@boron-containing palygorskite powder, it is brewed and diluted to form an organically modified filler solution with a mass concentration of 25%, and then mixed into a pulp pool containing pulp with a concentration of 15%. The fiber components in the pulp include larch fiber, poplar fiber, and wheat straw with a mass ratio of 6:3:1. It is mixed evenly with the pulp. The organically modified filler is 12% of the mass of the absolutely dry pulp. Then, a PPE wet strength agent is added. The addition amount of the PPE wet strength agent (cationic polyamide) is 0.68% of the mass of the absolutely dry pulp;

[0048] In the second step, after passing the pulp mixed in the first step through a 200-mesh sieve, it is introduced into a paper machine together with a sizing agent. The sizing agent is alkyl ketene dimer or alkenyl succinic anhydride. The addition amount of the sizing agent is 2% of the mass of the absolutely dry pulp. It successively undergoes flow spreading and forming, is dehydrated under vacuum conditions, and the humidity after dehydration is 40%. Then it is dried at 65°C, and the humidity after drying is 4%. Finally, it is wound up to obtain paper containing the organically modified filler.

[0049] Among them, the preparation process of the organically modified filler includes:

[0050] S1. Weigh palygorskite powder and mix it with sodium hydroxide solution. Under ultrasonic action, a uniform mixture is formed, and then the temperature is raised to 55 °C and stirred for 4 h to obtain activated palygorskite powder. Among them, the particle size of the palygorskite powder is 30 - 40 μm; the molar concentration of the sodium hydroxide solution is 0.5 mol / L, and the mass ratio of the palygorskite powder to the sodium hydroxide solution is 1:15.

[0051] S2. Weigh diphenyldihydroxysilane, activated palygorskite powder and xylene and place them in a reaction flask. Heat up to 125 °C. After stirring evenly, gradually add boric acid, and then heat up to 150 °C and stir and react for 10 h. Continuously separate the generated water, then remove xylene, continue to heat up to 360 °C and keep the temperature for reaction for 1.5 h. After the reaction is completed, cool to room temperature to obtain palygorskite encapsulated with polyborosiloxane. Among them, the mass ratio of diphenyldihydroxysilane, activated palygorskite powder, boric acid to xylene is 0.20:3:0.04:30;

[0052] S3. Place the palygorskite encapsulated with polyborosiloxane in a muffle furnace for sintering. The sintering temperature is 600 °C. After keeping the temperature for 3 h, boron-modified palygorskite is obtained.

[0053] S4. Weigh boron-modified palygorskite and mix it with deionized water. Under ultrasonic conditions, a uniform mixture is formed, and then under stirring conditions, continuously add aluminum chloride solution dropwise. After the addition is completed, continue to stir for 20 min to form an aluminum-containing mixture. Among them, the mass fraction of the aluminum chloride solution is 2.5%; the mass ratio of boron-modified palygorskite, aluminum chloride solution to deionized water is 1:6:15;

[0054] S5. First, weigh a small amount of sodium hexametaphosphate and dissolve it in deionized water, and then gradually and slowly add pectin and stir to form a uniform solution, that is, pectin solution. Among them, the degree of esterification of pectin is 15%, and the viscosity-average molecular weight is 20000; the mass ratio of sodium hexametaphosphate, pectin to deionized water is 0.4:2.5:100;

[0055] S6. Dropwise add the pectin solution into the aluminum-containing mixture, continuously stir during this period, and at the same time control the pH of the reaction solution to be 6 - 6.5. After the pectin solution is completely added, stir for 15 min, adjust the pH of the reaction solution to 7 - 7.5, continue to stir for 45 min, and then through precipitation, centrifugation, washing, suction filtration and drying, pectin aluminum @ boron-containing palygorskite powder is obtained. Among them, the mass ratio of the pectin solution to the aluminum-containing mixture is 2:1.

[0056] Example 2

[0057] A papermaking process using organically modified fillers, including:

[0058] First step: Weigh the organically modified filler pectin aluminum@boron-containing palygorskite powder. After brewing and dilution, an organically modified filler solution with a mass concentration of 20% is formed and mixed into a pulp tank containing pulp with a concentration of 10%. The fiber components in the pulp include larch fiber, poplar fiber, and wheat straw with a mass ratio of 5:2:1. It is mixed evenly with the pulp. The organically modified filler is 8% of the absolutely dry pulp mass. Then, add PPE wet strength agent. The addition amount of PPE wet strength agent (cationic polyamide) is 0.52% of the absolutely dry pulp mass.

[0059] Second step: After passing the pulp mixed in the first step through a 200-mesh sieve, it is introduced into a paper machine together with the sizing agent. The sizing agent is alkyl ketene dimer or alkenyl succinic anhydride. The addition amount of the sizing agent is 1% of the absolutely dry pulp mass. It successively undergoes flow pulping and forming, dewatering under vacuum conditions, and the humidity after dewatering is 30%. Then it is dried at 55°C, and the humidity after drying is 3%. Finally, it is wound up to obtain the paper containing the organically modified filler.

[0060] Among them, the preparation process of the organically modified filler includes:

[0061] S1: Weigh palygorskite powder and mix it with sodium hydroxide solution. Under ultrasonic action, a uniform mixture is formed, and then the temperature is raised to 50°C and stirred for 3 hours to obtain activated palygorskite powder. Among them, the particle size of palygorskite powder is 20 - 30μm; the molar concentration of sodium hydroxide solution is 0.5mol / L, and the mass ratio of palygorskite powder to sodium hydroxide solution is 1:10.

[0062] S2: Weigh diphenyldihydroxysilane, activated palygorskite powder, and xylene and place them in a reaction flask. Heat up to 125°C. After stirring evenly, gradually add boric acid, and then heat up to 145°C and stir and react for 8 hours. Remove the generated water at any time, then remove xylene, continue to heat up to 340°C, keep warm and react for 1 hour. After the reaction ends, cool to room temperature to obtain palygorskite encapsulated with polyborosiloxane. Among them, the mass ratio of diphenyldihydroxysilane, activated palygorskite powder, boric acid, and xylene is 0.13:2:0.03:20;

[0063] S3: Place the palygorskite encapsulated with polyborosiloxane in a muffle furnace for sintering. The sintering temperature is 550°C. After keeping warm for 2 hours, boron-containing modified palygorskite is obtained.

[0064] S4: Weigh boron-containing modified palygorskite and mix it with deionized water. Under ultrasonic conditions, a uniform mixture is formed, and then under stirring conditions, continuously dropwise add aluminum chloride solution. After the dropping is completed, continue to stir for 15 minutes to form an aluminum-containing mixed solution. Among them, the mass fraction of aluminum chloride solution is 1.5%; the mass ratio of boron-containing modified palygorskite, aluminum chloride solution, and deionized water is 1:5:10;

[0065] S5. First, weigh a small amount of sodium hexametaphosphate and dissolve it in deionized water. Then, gradually and slowly add pectin and stir to form a homogeneous solution, namely the pectin solution. Among them, the degree of esterification of pectin is 10%, and the viscosity-average molecular weight is 15,000. The mass ratio of sodium hexametaphosphate, pectin to deionized water is 0.3:0.5:100.

[0066] S6. Dropwise add the pectin solution into the aluminum-containing mixture while continuously stirring. At the same time, control the pH of the reaction solution to be 6 - 6.5. After the pectin solution is completely added, stir for 10 min, adjust the pH of the reaction solution to 7 - 7.5, and continue to stir for 30 min. Then, through precipitation, centrifugation, washing, suction filtration and drying, aluminum pectinate@boron-containing palygorskite powder is obtained. Among them, the mass ratio of the pectin solution to the aluminum-containing mixture is 1:1.

[0067] Example 3

[0068] A papermaking process using an organically modified filler includes:

[0069] In the first step, weigh the organically modified filler aluminum pectinate@boron-containing palygorskite powder. After brewing and dilution, form an organically modified filler solution with a mass concentration of 30%, and mix it into a pulp pool containing pulp with a concentration of 20%. The fiber components in the pulp include larch fiber, poplar fiber and wheat straw with a mass ratio of 7:4:1. Mix it evenly with the pulp. The organically modified filler is 16% of the mass of the dry pulp. Then add PPE wet strength agent. The addition amount of PPE wet strength agent (cationic polyamide) is 0.85% of the mass of the dry pulp.

[0070] In the second step, after passing the pulp mixed in the first step through a 200-mesh sieve, introduce it into a paper machine together with a sizing agent. The sizing agent is alkyl ketene dimer or alkenyl succinic anhydride. The addition amount of the sizing agent is 3% of the mass of the dry pulp. Pass through the headbox and forming successively, dehydrate under vacuum conditions. The humidity after dehydration is 50%. Then dry at 80°C. The humidity after drying is 5%. Finally, wind up to obtain the paper containing the organically modified filler.

[0071] Among them, the preparation process of the organically modified filler includes:

[0072] S1. Weigh palygorskite powder and mix it with sodium hydroxide solution. Under ultrasonic action, form a homogeneous mixture, and then raise the temperature to 60°C and stir for 5 h to obtain activated palygorskite powder. Among them, the particle size of the palygorskite powder is 40 - 50 μm; the molar concentration of the sodium hydroxide solution is 0.5 mol / L, and the mass ratio of the palygorskite powder to the sodium hydroxide solution is 1:20.

[0073] S2. Weigh diphenyldihydroxysilane, activated palygorskite powder and xylene, place them in a reaction flask, heat up to 125 °C. After stirring evenly, gradually add boric acid, then heat up to 150 °C, stir and react for 12 h, and separate the generated water at any time. Then remove the xylene, continue to heat up to 380 °C, keep the temperature for reaction for 2 h. After the reaction is completed, cool to room temperature to obtain palygorskite encapsulated with polyborosiloxane; among them, the mass ratio of diphenyldihydroxysilane, activated palygorskite powder, boric acid and xylene is 0.26:4:0.06:40;

[0074] S3. Place the palygorskite encapsulated with polyborosiloxane in a muffle furnace for sintering. The sintering temperature is 600 °C. After keeping the temperature for 4 h, boron-modified palygorskite is obtained.

[0075] S4. Weigh boron-modified palygorskite and mix it with deionized water to form a uniform mixed solution under ultrasonic conditions. Then, under stirring conditions, continuously dropwise add aluminum chloride solution. After the dropping is completed, continue to stir for 30 min to form an aluminum-containing mixed solution; among them, the mass fraction of the aluminum chloride solution is 3%; the mass ratio of boron-modified palygorskite, aluminum chloride solution and deionized water is 1:8:20;

[0076] S5. First, weigh a small amount of sodium hexametaphosphate and dissolve it in deionized water, and then gradually and slowly add pectin and stir to form a uniform solution, namely pectin solution; among them, the degree of esterification of pectin is 25%, and the viscosity-average molecular weight is 25,000; the mass ratio of sodium hexametaphosphate, pectin and deionized water is 0.6:5:100;

[0077] S6. Dropwise add the pectin solution into the aluminum-containing mixed solution, continuously stir during this period, and at the same time control the pH of the reaction solution to be 6 - 6.5. After the pectin solution is completely dropped, stir for 20 min, adjust the pH of the reaction solution to 7 - 7.5, continue to stir for 60 min, and then through precipitation, centrifugation, washing, suction filtration and drying, pectin aluminum@boron-containing palygorskite powder is obtained; among them, the mass ratio of the pectin solution to the aluminum-containing mixed solution is 3:1.

[0078] Comparative Example 1

[0079] A papermaking process using an organically modified filler, which is different from Example 1 in that the organically modified filler in Example 1 is replaced with a common filler, that is, the filler is palygorskite powder with a particle size of 30 - 40 μm.

[0080] Comparative Example 2

[0081] A papermaking process using an organically modified filler, which is different from Example 1 in that the preparation method of the organically modified filler is different. The specific preparation method of the organically modified filler includes:

[0082] S1. Weigh palygorskite powder and mix it with sodium hydroxide solution. Under ultrasonic action, form a homogeneous mixture, and then raise the temperature to 55 °C and stir for 4 h to obtain activated palygorskite powder. Among them, the particle size of the palygorskite powder is 30 - 40 μm; the molar concentration of the sodium hydroxide solution is 0.5 mol / L, and the mass ratio of the palygorskite powder to the sodium hydroxide solution is 1:15.

[0083] S2. Weigh diphenyldihydroxysilane, activated palygorskite powder and xylene and place them in a reaction flask. Raise the temperature to 125 °C. After stirring evenly, gradually add boric acid, and then raise the temperature to 150 °C and stir and react for 10 h. Remove the generated water at any time, then remove xylene, continue to raise the temperature to 360 °C and keep the temperature for 1.5 h. After the reaction is completed, cool to room temperature to obtain palygorskite encapsulated with polyborosiloxane. Among them, the mass ratio of diphenyldihydroxysilane, activated palygorskite powder, boric acid and xylene is 0.20:3:0.04:30;

[0084] S3. Place the palygorskite encapsulated with polyborosiloxane in a muffle furnace for sintering. The sintering temperature is 600 °C. After keeping the temperature for 3 h, obtain boron-modified palygorskite.

[0085] Comparative Example 3

[0086] A papermaking process using an organically modified filler, which is different from Example 1 in that the preparation method of the organically modified filler is different. The specific preparation method of the organically modified filler includes:

[0087] S1. Weigh palygorskite powder and mix it with sodium hydroxide solution. Under ultrasonic action, form a homogeneous mixture, and then raise the temperature to 55 °C and stir for 4 h to obtain activated palygorskite powder. Among them, the particle size of the palygorskite powder is 30 - 40 μm; the molar concentration of the sodium hydroxide solution is 0.5 mol / L, and the mass ratio of the palygorskite powder to the sodium hydroxide solution is 1:15.

[0088] S2. Weigh activated palygorskite powder and mix it with deionized water. Under ultrasonic conditions, form a homogeneous mixture, and then under stirring conditions, continuously dropwise add aluminum chloride solution. After the dropping is completed, continue to stir for 20 min to form an aluminum-containing mixture. Among them, the mass fraction of the aluminum chloride solution is 2.5%; the mass ratio of the activated palygorskite powder, the aluminum chloride solution and the deionized water is 1:6:15;

[0089] S3. First weigh a small amount of sodium hexametaphosphate and dissolve it in deionized water, and then gradually and slowly add pectin and stir to form a homogeneous solution, that is, a pectin solution. Among them, the degree of esterification of pectin is 15%, and the viscosity-average molecular weight is 20,000; the mass ratio of sodium hexametaphosphate, pectin and deionized water is 0.4:2.5:100;

[0090] S4. Drop the pectin solution into the aluminum-containing mixture drop by drop, continuously stir during this process, and at the same time control the pH of the reaction solution to be 6 - 6.5. After the pectin solution is completely dropped, stir for 15 min, adjust the pH of the reaction solution to 7 - 7.5, continue to stir for 45 min, and then through precipitation, centrifugation, washing, suction filtration and drying, aluminum pectinate@palygorskite powder is obtained; wherein, the mass ratio of the pectin solution to the aluminum-containing mixture is 2:1.

[0091] Experimental Example

[0092] In order to prove the final effect of Example 1 of the present invention, a total of four control experiments, Comparative Examples 1 - 3, were set up. The papers obtained in Example 1 and Comparative Examples 1 - 3 were detected and compared. The detection standards were GB / T 453, GB / T 455.1, GB / T 24328.4, and GB / T 463; the immersion time for the wet tensile strength was 1 h and the temperature was 25 °C.

[0093] The results are shown in Table 1.

[0094] Table 1 Detection Results of Paper Parameters

[0095]

[0096]

[0097] It can be seen from Table 1 that compared with Comparative Examples 1 - 3, both the dry tensile strength and the wet tensile strength of Example 1 have better improvements, and the wet strength retention rate of Example 1 can reach 40%, indicating that its strength is still very strong under humid conditions; while the wet strength retention rates of Comparative Example 1 and Comparative Example 2 are less than 30%, indicating that their strengths decrease significantly in a humid environment; although the wet strength retention rate of Comparative Example 3 can reach 38.1%, its strength itself is quite different from that of Example 1. Therefore, it shows that the paper of Example 1 of the present invention not only has sufficient dry strength, but also has a better wet strength retention rate, indicating that its stability in a humid environment is also stronger.

[0098] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the protection scope of the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical solutions of the present invention can be modified or equivalently replaced without departing from the essence and scope of the technical solutions of the present invention.

Claims

1. A papermaking process using organically modified fillers, characterized in that, Including: First step: Weigh the organically modified filler, after brewing and diluting it with pure water, mix it into the pulp pool and mix it evenly with the pulp. Second step: After screening the pulp mixed in the first step, introduce it into the paper machine. After flowing the pulp, forming, dewatering, drying and winding, paper containing the organically modified filler is obtained. Among them, the organically modified filler is aluminum pectin / palygorskite powder containing boron. The preparation process of the organically modified filler includes: (1) Treat palygorskite powder in a sodium hydroxide solution to obtain activated palygorskite powder. (2) Let the activated palygorskite powder participate in the reaction of diphenyldihydroxysilane and boric acid, and then after sintering treatment, boron-containing modified palygorskite is obtained. (3) Add a solution containing aluminum ions to the boron-containing modified palygorskite, mix well, and then dropwise add a pectin solution, control the pH of the reaction, and obtain aluminum pectin / palygorskite powder after the reaction. The process of the second step in the preparation of the organically modified filler includes: S1. Weigh diphenyldihydroxysilane, activated palygorskite powder and xylene and place them in a reaction flask. Heat up to 125 °C. After stirring evenly, gradually add boric acid, and then heat up to 145 - 150 °C, stir and react for 8 - 12 h, and separate the generated water at any time. Then remove xylene, continue to heat up to 340 - 380 °C, keep the temperature for 1 - 2 h, and cool to room temperature after the reaction to obtain palygorskite wrapped with polyborosiloxane. S2. Sinter the palygorskite wrapped with polyborosiloxane in a muffle furnace. The sintering temperature is 550 - 600 °C. After keeping the temperature for 2 - 4 h, boron-containing modified palygorskite is obtained.

2. The papermaking process using organically modified fillers according to claim 1, characterized in that, In the first step, after brewing and diluting the organically modified filler with pure water, an organically modified filler solution with a mass concentration of 20% - 30% is formed; the organically modified filler is 8% - 16% of the mass of the absolutely dry pulp.

3. A papermaking process using an organically modified filler according to claim 1, characterized in that, In the first step, after the organically modified filler is mixed into the pulp pool, a PPE wet strength agent is also added. The addition amount of the PPE wet strength agent is 0.52% - 0.85% of the mass of the absolutely dry pulp.

4. A papermaking process using organically modified fillers according to claim 1, characterized in that, In the first step, the concentration of the pulp in the pulp pool is 10% - 20%. The pulp is a plant fiber slurry, and the raw materials of the plant fiber include at least one of coniferous wood, broad-leaved wood, and grass plants.

5. A papermaking process using organically modified fillers according to claim 1, characterized in that, In the second step, the screening is through a 200-mesh sieve; the dewatering is carried out under vacuum conditions, and the humidity after dewatering is 30% - 50%; the drying is carried out at 55 - 80 °C, and the humidity after drying is 3% - 5%.

6. A papermaking process using organically modified fillers according to claim 1, characterized in that, In the second step, after screening the mixed pulp, it is introduced into the paper machine together with a sizing agent. The sizing agent is alkyl ketene dimer or alkenyl succinic anhydride, and the addition amount of the sizing agent is 1% - 3% of the mass of the absolutely dry pulp.

7. A papermaking process using organically modified fillers according to claim 1, characterized in that, The process of the first step in the preparation of the organically modified filler includes: Weigh palygorskite powder and mix it with a sodium hydroxide solution. Under ultrasonic action, a uniform mixture is formed, and then the temperature is raised and stirred to obtain activated palygorskite powder.

8. A papermaking process using organically modified fillers according to claim 1, characterized in that, The process of the third step in the preparation of the organically modified filler includes: S3. Weigh the boron-modified palygorskite and mix it with deionized water to form a uniform mixture under ultrasonic conditions. Then, under stirring conditions, continuously add dropwise the mixed solution of aluminum chloride. After the addition is completed, continue stirring for 15 - 30 min to form an aluminum-containing mixed solution; S4. First, weigh a small amount of sodium hexametaphosphate and dissolve it in deionized water, and then gradually and slowly add pectin and stir to form a uniform solution, namely the pectin solution; S5. Dropwise add the pectin solution into the aluminum-containing mixed solution, continuously stir during this period, and at the same time control the pH of the reaction solution to be 6 - 6.

5. After the second mixed solution is completely added, stir for 10 - 20 min, adjust the pH of the reaction solution to 7 - 7.5, continue stirring for 30 - 60 min, and then through precipitation, centrifugation, washing, suction filtration and drying, the aluminum pectin / palygorskite powder containing boron is obtained.

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