A method for preparing high-white and highly activated heavy calcium carbonate using a composite functional additive

Abstract

The invention provides a method for preparing high-white and high-activated ground calcium carbonate with a composite functional additive, comprising the following steps: mixing DSD acid, water and a saturated Na2CO3 solution and stirring until the solution is clarified, dripping the mixture into a mixture of cyanuric chloride and ice water, stirring in an ice bath and controlling the temperature at 3-5°C for reaction for 1.5h; then adding 3-aminopropyltrimethoxysilane and 4-aminobenzenesulfonic acid, adjusting the pH to 8 with a saturated Na2CO3 solution, controlling the temperature at 40-45°C, and reacting for 3.5h; then adding diethylaminoethyl methacrylate Ester, maintain pH=9 with saturated Na2CO3 solution, heat to 85-90℃, stir to react for 6h, cool to room temperature; finally add sodium dodecylbenzene sulfonate and water, heat and stir evenly to obtain composite functional additive; add 20Kg of heavy calcium carbonate powder with 600-1250 mesh and whiteness (CIE) of 92-94, stir, filter and dry to obtain high-white and high-activated heavy calcium carbonate, whose oil absorption value is 12-15g / 100g, and whiteness value (CIE) is increased by 3.5-4.0. The patented technology of the present invention can significantly improve the whiteness value of calcium carbonate powder and effectively reduce the oil absorption value of heavy calcium carbonate powder, achieving the dual effects of whitening and surface activation.

Description

Technical Field

[0001] The invention relates to a method for preparing high-whiteness and high-activation heavy calcium carbonate using a composite functional additive, and specifically relates to a method for preparing high-whiteness and high-activation heavy calcium carbonate using a composite functional additive. Background Art

[0002] Calcium carbonate powder is a low-carbon, green and environmentally friendly mineral filler, which is widely used in rubber, plastic, papermaking, coating, ink, medicine and other industries. Since CaCO3 raw materials are widely available, inexpensive and non-toxic, it can improve the mechanical properties of composite materials and reduce the cost of products, so it is the largest inorganic filler used in polymer composite materials.

[0003] There are defects in the direct use of calcium carbonate in polymers. Since calcium carbonate is hydrophilic and oleophobic, its affinity with polymers deteriorates, and it is difficult to disperse evenly in organic media, resulting in interface defects between the two materials, which leads to a decrease in the mechanical properties of the composite material. Therefore, it is necessary to add a modifier to modify its surface. In addition, organic surface modifiers are prone to discoloration during processing or heating, resulting in a decrease in the whiteness value of the modified calcium carbonate powder, which seriously affects the quality and added value of the heavy calcium carbonate powder and downstream products. Therefore, it is particularly urgent and necessary to research and develop a composite functional additive and use it to prepare high-white and highly activated heavy calcium carbonate. After searching, a method for preparing high-white and highly activated heavy calcium carbonate using a composite functional additive has not been reported so far. The market demand is very urgent and the application prospects are very broad. Summary of the invention

[0004] Existing organic surface modifiers are easily oxidized or decomposed and discolored when modifying calcium carbonate powder, resulting in a decrease in the whiteness value of the modified calcium carbonate powder, which seriously affects the quality and added value of the calcium carbonate powder and downstream products. The problem to be solved by the present invention is to provide a method for preparing high-whiteness and highly activated heavy calcium carbonate using a composite functional additive. This technology can efficiently reduce the oil absorption value of the calcium carbonate powder, improve the surface modification effect, effectively improve the whiteness value of the modified calcium carbonate powder, and significantly improve the quality and added value of the calcium carbonate powder. It is an effective method for preparing high-whiteness and highly activated heavy calcium carbonate. The method for preparing high-whiteness and highly activated heavy calcium carbonate using a composite functional additive of the present invention consists of the following steps:

[0005] (1) 1 mmol DSD acid, 10 mL water and saturated Na2CO3 solution were stirred until clear;

[0006] (2) 2mmol of cyanuric chloride and 10mL of ice water, stir in an ice bath, slowly drop (1) into the mixture, and control the temperature at 3-5℃ to react for 1.5h;

[0007] (3) Add 1 mmol 3-aminopropyltrimethoxysilane and 1 mmol 4-aminobenzenesulfonic acid, adjust the pH to 8 with saturated Na2CO3 solution, raise the temperature to 40-45°C, and react for 3.5 hours;

[0008] (4) Add 2 mmol of diethylaminoethyl methacrylate, maintain pH = 9 with saturated Na2CO3 solution, raise the temperature to 85-90°C, stir and react for 6 hours, and cool to room temperature;

[0009] (5) adding sodium dodecylbenzene sulfonate and 15 L of water, heating and stirring evenly to obtain a composite functional additive;

[0010] (6) Add 20 kg of heavy calcium carbonate powder, stir, filter, and dry to obtain high-white and highly activated heavy calcium carbonate.

[0011] The mass of the sodium dodecylbenzene sulfonate described in the above step (5) is preferably 0.2-0.3 kg;

[0012] The temperature in step (5) is preferably 80-85°C;

[0013] The heavy calcium carbonate powder described in step (6) above preferably has a mesh size of 600 to 1250 and a whiteness (CIE) of 92 to 94;

[0014] The time described in the above step (6) is preferably 10 to 15 minutes.

[0015] Experimental data show that the oil absorption value of the calcium carbonate powder obtained by the technology of the present invention is 12-15g / 100g, and the whiteness value (CIE) is increased by 3.5-4.0.

[0016] The method for preparing high-whiteness and high-activation heavy calcium carbonate by using a composite functional additive of the present invention can effectively solve the problem of decreased whiteness value of modified calcium carbonate powder due to oxidation or decomposition during processing or heating of an organic surface modifier, significantly improve the whiteness value, and effectively reduce the oil absorption value of the powder, achieving the dual effects of whitening and surface activation, and is an effective method for preparing high-whiteness and high-activation heavy calcium carbonate, with great economic value and promotion value. The present invention is further described below in conjunction with embodiments. DETAILED DESCRIPTION

[0017] Embodiment 1:

[0018] Processing of heavy calcium carbonate with 600 mesh, oil absorption value of 29g / 100g and whiteness of 94 (CIE):

[0019] (1) 1 mmol DSD acid, 10 mL water and saturated Na2CO3 solution were stirred until clear;

[0020] (2) 2mmol of cyanuric chloride and 10mL of ice water, stir in an ice bath, slowly drop (1) into the mixture, and control the temperature at 3-5℃ to react for 1.5h;

[0021] (3) Add 1 mmol 3-aminopropyltrimethoxysilane and 1 mmol 4-aminobenzenesulfonic acid, adjust the pH to 8 with saturated Na2CO3 solution, raise the temperature to 40-45°C, and react for 4 hours;

[0022] (4) Add 2 mmol of diethylaminoethyl methacrylate, maintain pH = 9 with saturated Na2CO3 solution, raise the temperature to 85-90°C, stir and react for 6 hours, and cool to room temperature;

[0023] (5) Add 0.2 kg sodium dodecylbenzene sulfonate and 15 L water, stir evenly, and heat to 80 ° C;

[0024] (6) Add 20 kg of heavy calcium carbonate powder, stir for 15 minutes, filter and dry to obtain high-white and highly activated heavy calcium carbonate with an oil absorption value of 12 g / 100 g CaCO3 and a whiteness (CIE) of 98.

[0025] Embodiment 2:

[0026] Processing of heavy calcium carbonate with 800 mesh, oil absorption value of 33g / 100g and whiteness of 92 (CIE):

[0027] (1) 1 mmol DSD acid, 10 mL water and saturated Na2CO3 solution were stirred until clear;

[0028] (2) 2mmol of cyanuric chloride and 10mL of ice water, stir in an ice bath, slowly drop (1) into the mixture, and control the temperature at 3-5℃ to react for 1.5h;

[0029] (3) Add 1 mmol 3-aminopropyltrimethoxysilane and 1 mmol 4-aminobenzenesulfonic acid, adjust the pH to 8 with saturated Na2CO3 solution, raise the temperature to 40-45°C, and react for 4 hours;

[0030] (4) Add 2 mmol of diethylaminoethyl methacrylate, maintain pH = 9 with saturated Na2CO3 solution, raise the temperature to 85-90°C, stir and react for 6 hours, and cool to room temperature;

[0031] (5) Add 0.3 kg sodium dodecylbenzene sulfonate and 15 L water, stir evenly, and heat to 85 ° C;

[0032] (6) Add 20 kg of heavy calcium carbonate powder, stir for 20 min, filter and dry to obtain high-white and highly activated heavy calcium carbonate with an oil absorption value of 14 g / 100 g and a whiteness (CIE) of 95.5.

[0033] Embodiment 3:

[0034] Processing of heavy calcium carbonate with 1250 mesh, oil absorption value of 34.5g / 100 and whiteness of 93 (CIE):

[0035] (1) 1 mmol DSD acid, 10 mL water and saturated Na2CO3 solution were stirred until clear.

[0036] (2) 2 mmol of cyanuric chloride and 10 mL of ice water, stir in an ice bath, slowly drop (1) into the mixture, and control the temperature at 3-5°C to react for 1.5 h.

[0037] (3) Add 1 mmol of 3-aminopropyltrimethoxysilane and 1 mmol of 4-aminobenzenesulfonic acid, adjust the pH to 8 with saturated Na2CO3 solution, raise the temperature to 40-45°C, and react for 4 hours.

[0038] (4) Add 2 mmol of diethylaminoethyl methacrylate and maintain the pH value at 9 with saturated Na2CO3 solution, raise the temperature to 85-90°C, stir and react for 6 hours, and cool to room temperature.

[0039] (5) Add 0.25 kg sodium dodecylbenzene sulfonate and 20 L water, stir evenly, and heat to 80 ° C;

[0040] (6) Add 20 kg of heavy calcium carbonate powder, stir for 15 minutes, filter and dry to obtain high-white and highly activated heavy calcium carbonate with an oil absorption value of 14 g / 100 g CaCO3 and a whiteness (CIE) of 97.

[0041] Experimental data proves that compared with untreated heavy calcium carbonate, a method for preparing high-white and highly activated heavy calcium carbonate with a composite functional additive can significantly reduce the oil absorption value of calcium carbonate powder and significantly improve the whiteness value of heavy calcium carbonate after surface activation. It is an effective method for preparing high-white and highly activated heavy calcium carbonate.

[0042] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A method for preparing high-white and high-activated heavy calcium carbonate using a composite functional additive, characterized in that: The method comprises the following steps: (1) 1 mmol DSD acid, 10 mL water and saturated Na2CO3 solution were stirred until clear; (2) 2mmol of cyanuric chloride and 10mL of ice water, stir in an ice bath, slowly drop (1) into the mixture, and control the temperature at 3-5℃ to react for 1.5h; (3) Add 1 mmol 3-aminopropyltrimethoxysilane and 1 mmol 4-aminobenzenesulfonic acid, adjust the pH to 8 with saturated Na2CO3 solution, raise the temperature to 40-45°C, and react for 3.5 hours; (4) Add 2 mmol of diethylaminoethyl methacrylate, maintain pH = 9 with saturated Na2CO3 solution, raise the temperature to 85-90°C, stir and react for 6 hours, and cool to room temperature; (5) adding sodium dodecylbenzene sulfonate and 15 L of water, heating and stirring to obtain a composite functional additive; (6) Add 20 kg of heavy calcium carbonate powder, stir for a period of time, filter, and dry to obtain high-white and highly activated heavy calcium carbonate.

2. The method for preparing high-white and high-activated ground calcium carbonate using a composite functional additive according to claim 1, characterized in that: The dosage of sodium dodecylbenzene sulfonate in step (5) is 0.2-0.3 kg.

3. The method for preparing high-white and high-activated ground calcium carbonate using a composite functional additive according to claim 1, characterized in that: The heating temperature in step (5) is 80-85°C.

4. The method for preparing high-whiteness and high-activation ground calcium carbonate using a composite functional additive according to claim 1, characterized in that: The heavy calcium carbonate powder described in step (6) has a mesh size of 600-1250 and a CIE whiteness of 92-94.

5. The method for preparing high-whiteness and high-activation ground calcium carbonate using a composite functional additive according to claim 1, characterized in that: The stirring time in step (6) is 10 to 15 minutes.