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CN-121991524-A - Plastic defoamer and preparation method and application thereof

CN121991524ACN 121991524 ACN121991524 ACN 121991524ACN-121991524-A

Abstract

The invention relates to an auxiliary material for plastic processing, in particular to a plastic defoaming agent and a preparation method and application thereof, wherein the preparation method comprises the steps of selecting mature shell fruits, separating shells from pulp, drying the shells at normal temperature until the water content is less than or equal to 5%, crushing the shells into shell powder for standby, immersing the pulp in boiling water for 3-4min, fishing out the shells, drying the shells until the water content is less than or equal to 5%, crushing the shells into meat powder for standby, immersing the shell powder in a 19% (w/v) sodium hydroxide aqueous solution to obtain a mixed solution, putting the mixed solution into a reaction kettle to obtain a first extract, adding water into the meat powder to a feed liquid ratio of 1:25-50, using citric acid to adjust the pH value to 2.0-3.0, heating the meat powder to 85-95 ℃ for reacting for 45-90min to obtain a second extract, mixing the first extract and the second extract to obtain the plastic defoaming agent, adopting plant extracts and derivatives as active components, discarding silicone oil, further preventing the mechanical performance of plastic injection products from being degraded due to silicone oil, and being more environment-friendly, and being degradable due to plant component processing.

Inventors

  • YAN XUEWEI
  • CHEN JIYUN

Assignees

  • 佛山市莱彩颜料色母科技有限公司

Dates

Publication Date
20260508
Application Date
20260320

Claims (10)

  1. 1. The preparation method of the plastic defoaming agent is characterized by comprising the following steps of: selecting mature shell fruits, separating shells from pulps, drying the shells at normal temperature until the water content is less than or equal to 5%, and crushing the shells into shell powder for later use, soaking the shells in boiling water for 3-4min after the pulps are removed, fishing out the shells, drying the shells at normal temperature until the water content is less than or equal to 5%, and crushing the shells into meat powder for later use; Immersing shell powder in 19% (w/v) sodium hydroxide aqueous solution to obtain a mixed solution, wherein the mass ratio of the shell powder to the sodium hydroxide in the mixed solution is 1:200, adding the mixed solution into a reaction kettle, respectively adding chloromethane and epoxypropane which are 30 times of the mass of the shell powder, reacting at 50-80 ℃ under the pressure of 1.5-1.8MPa for 12-14h, fishing out the shell powder after the reaction is finished, flushing the shell powder to pH7.0-7.5, and then air-drying until the water content is less than or equal to 5% for standby, thereby obtaining a first extract; Adding water into meat powder until the feed-liquid ratio is 1:25-50, regulating the pH value to 2.0-3.0 by using citric acid, heating to 85-95 ℃ and then reacting for 45-90min, regulating the pH value to 6.0-7.0 by using 10% (w/v) sodium hydroxide aqueous solution; and step four, mixing the first extract and the second extract according to the mass ratio of 1:10-15 to obtain the plastic defoamer.
  2. 2. The method of claim 1, wherein the shell powder is sieved with a 100-mesh sieve in the first step.
  3. 3. The method of preparing a plastic defoamer according to claim 1, wherein the second extract in the third step is ground and then passes through a 80-mesh sieve.
  4. 4. The method of claim 1, wherein the mixing of the first extract and the second extract in the fourth step is performed by an air-flow mixing method.
  5. 5. A plastic defoamer obtainable by the process of claim 1.
  6. 6. A method of using the plastic defoamer of claim 5, comprising the steps of: Weighing plastic defoamer accounting for 1-2% of the mass of the plastic to be processed and polyvinylpyrrolidone accounting for 0.3-0.5% of the mass of the plastic to be processed, heating the mixture of the plastic to be processed and the plastic defoamer and polyvinylpyrrolidone to 140-150 ℃, and then injection molding.
  7. 7. The method of claim 6, wherein the plastic to be processed is polystyrene.
  8. 8. A method of using the plastic defoamer of claim 5, comprising the steps of: Weighing plastic defoamer accounting for 2-5% of the mass of the plastic to be processed and tween 80 accounting for 0.5-0.8% of the mass of the plastic to be processed, mixing the plastic to be processed and the plastic defoamer, heating the mixture of the plastic to be processed and the tween 80 to 120-130 ℃, and then injection molding.
  9. 9. The method of claim 8, wherein the plastic to be processed is a low density polyethylene.
  10. 10. The method according to claim 7 or 9, wherein the temperature of the rear section of the injection molding barrel is 160-180 ℃, the temperature of the middle section is 180-210 ℃, the temperature of the front section is 200-220 ℃, the temperature of the nozzle is 200-215 ℃, and the injection pressure is set to be 50-80MPa.

Description

Plastic defoamer and preparation method and application thereof Technical Field The invention relates to an auxiliary material for plastic processing, in particular to a plastic defoaming agent, a preparation method and application thereof. Background The plastic raw material contains a small amount of water, if bubbles or water waves are not eliminated from forming on the surface of the plastic product, the mechanical strength and the appearance of the plastic product are adversely affected. The traditional defoaming process generally adopts electric heating air drying, but because of larger energy consumption and overlong treatment time, plastic defoamers are mainly adopted for replacing the traditional defoaming process. The plastic defoamer mainly uses silicone oil and silica gel as core active ingredients. The silicone oil damages the plastic foam structure by reducing the surface tension, and the silicone oil adsorbs moisture, thereby eliminating bubbles. However, silicone oils reduce the impact strength, tensile strength, heat resistance, and other properties of plastics such as polycarbonates, polyesters, polyethers, and the like. It is therefore necessary to develop a silicone oil-free plastic defoamer. Disclosure of Invention In view of the shortcomings of the prior art, one of the purposes of the present invention is to provide a method for preparing a plastic defoaming agent, another purpose of the present invention is to provide the plastic defoaming agent, and a third purpose of the present invention is to provide a method for using the plastic defoaming agent. One of the purposes of the invention is achieved by the following technical scheme: A preparation method of a plastic defoaming agent comprises the following steps: Selecting mature shell tree (Couroupita guianensisabl) fruits, separating shells from pulps, drying the shells at normal temperature until the water content is less than or equal to 5%, and crushing the shells into shell powder for later use, soaking the shells in boiling water for 3-4min after removing the seeds, fishing out the shells, drying the shells at normal temperature until the water content is less than or equal to 5%, and crushing the shells into meat powder for later use; Immersing shell powder in 19% (w/v) sodium hydroxide aqueous solution to obtain a mixed solution, wherein the mass ratio of the shell powder to the sodium hydroxide in the mixed solution is 1:200, adding the mixed solution into a reaction kettle, respectively adding chloromethane and epoxypropane which are 30 times of the mass of the shell powder, reacting at 50-80 ℃ under the pressure of 1.5-1.8MPa for 12-14h, fishing out the shell powder after the reaction is finished, flushing the shell powder to pH7.0-7.5, and then air-drying until the water content is less than or equal to 5% for standby, thereby obtaining a first extract; Adding water into meat powder until the feed-liquid ratio is 1:25-50, regulating the pH value to 2.0-3.0 by using citric acid, heating to 85-95 ℃ and then reacting for 45-90min, regulating the pH value to 6.0-7.0 by using 10% (w/v) sodium hydroxide aqueous solution; and step four, mixing the first extract and the second extract according to the mass ratio of 1:10-15 to obtain the plastic defoamer. Further, the shell powder in the first step is sieved by a 100-mesh sieve. Shell powder of sufficient fineness is advantageous to provide sufficient contact surface for modification. Further, the second extract in the third step is ground and then sieved by a 80-mesh sieve. Although the fineness of the component itself does not substantially affect the subsequent defoaming, too coarse particles are detrimental to mixing with the first extract and should be ground and sieved. Further, the mixing of the first extract and the second extract in the fourth step adopts an air flow mixing method. Because the fineness of the two materials is different, the components are different, the texture is fine and smooth, and the mechanical grinding and mixing are not facilitated, the air flow mixing method is adopted. The second purpose of the invention is realized by the following technical scheme: A plastic defoamer obtained by the preparation method. The third object of the invention is achieved by the following technical scheme: The application method of the plastic defoamer comprises the following steps: Weighing plastic defoamer accounting for 1-2% of the mass of the plastic to be processed and polyvinylpyrrolidone accounting for 0.3-0.5% of the mass of the plastic to be processed, heating the mixture of the plastic to be processed and the plastic defoamer and polyvinylpyrrolidone to 140-150 ℃, and then injection molding. Further, the plastic to be processed is Polystyrene (PS). The application method of the plastic defoamer comprises the following steps: Weighing plastic defoamer accounting for 2-5% of the mass of the plastic to be processed and tween 80 accounting for 0.5-0.8% of the ma