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CN-122013600-A - Composite filler, fluorine-free oil-proof paper based on physical plugging and preparation method of fluorine-free oil-proof paper

CN122013600ACN 122013600 ACN122013600 ACN 122013600ACN-122013600-A

Abstract

The invention discloses a composite filler, fluorine-free oil-proof paper based on physical plugging and a preparation method thereof, belonging to the technical field of fluorine-free oil-proof paper, wherein the composite filler is prepared by compounding chitosan modified montmorillonite and alkyl amidated nanocellulose, the dispersibility and stability of the montmorillonite in a paper pulp system are enhanced by modifying the montmorillonite with chitosan, so that the montmorillonite forms a continuous layered barrier structure inside a paper sheet, the alkyl amidated nanocellulose is introduced as a flexible connecting component, the fluorine-free oil-proof paper can realize excellent oil-proof performance without depending on a surface coating, and can keep stable oil-proof effect under actual use conditions such as friction, folding and the like, thereby being applicable to application scenes with higher requirements on environmental protection and use reliability such as food packaging and the like.

Inventors

  • HOU FANGDONG
  • Ge Shenbo
  • WANG XINWEI
  • ZHAO WEI
  • XU SHI

Assignees

  • 济宁聚升造纸有限公司

Dates

Publication Date
20260512
Application Date
20260203

Claims (10)

  1. 1. The composite filler is characterized by being prepared by mixing chitosan modified montmorillonite and alkyl amidated nanocellulose in a wet way, and comprises the following components in parts by mass: 40-60 parts of chitosan modified montmorillonite and 20-30 parts of alkyl amidated nanocellulose; The alkyl amidated nanocellulose is prepared by the following steps: And (3) placing the dodecyl amine and the absolute ethyl alcohol into a reaction kettle, stirring for 10-20min at 25-35 ℃, adding the carboxyl-rich nanocellulose suspension, reacting for 4-6h at the same stirring speed at 60-80 ℃, centrifuging, collecting the lower-layer solid, washing, and freeze-drying to constant weight to obtain the alkyl amidated nanocellulose.
  2. 2. A composite filler according to claim 1, wherein the amount of the dodecanol, the carboxyl group rich nanocellulose suspension and the absolute ethanol is in the ratio of 10-20g:2-3l:100-200mL.
  3. 3. A composite filler according to claim 2, wherein the carboxyl-rich nanocellulose suspension is prepared by: and (3) placing TEMPO nanocellulose, a citric acid solution with the concentration of 1mol/L and deionized water into a reaction kettle, reacting for 1-3 hours at 60-80 ℃, centrifuging, washing, and dialyzing to obtain a carboxyl-rich nanocellulose suspension.
  4. 4. A composite filler according to claim 3, wherein the TEMPO nanocellulose, citric acid solution and deionized water are used in a ratio of 60-80g:120-160ml:2-3L.
  5. 5. A composite filler according to claim 1, wherein the chitosan modified montmorillonite is prepared by: placing montmorillonite and deionized water into a reaction kettle, performing ultrasonic dispersion for 1-2h at 25-35 ℃, adding a mixed solution prepared from chitosan and glacial acetic acid with the concentration of 2wt%, reacting for 20-24h at 50-60 ℃, filtering, washing a filter cake with deionized water until the pH value of the deionized water is 7, and performing vacuum drying until the weight is constant to obtain the chitosan modified montmorillonite.
  6. 6. The composite filler according to claim 5, wherein the amount ratio of montmorillonite, chitosan, glacial acetic acid and deionized water is 60-80 g/10-15 g/600-800 ml/1-1.5L.
  7. 7. The fluorine-free oil-proof paper based on physical plugging is characterized by comprising the following raw materials in parts by mass: 200-400 parts of fiber brooming slurry, 30-50 parts of composite filler and 4-8 parts of cationic starch; the composite filler is the composite filler according to any one of claims 1 to 6.
  8. 8. The method for preparing fluorine-free oil-proof paper based on physical plugging according to claim 7, which is characterized by comprising the following steps: Placing the fiber brooming slurry, the composite filler and the cationic starch in a high-speed stirrer, stirring for 1-2 hours at a stirring rate of 800-1200r/min, mixing, manufacturing the mixed slurry, pressing for 1-3 minutes in a multifunctional squeezer, and drying by blowing until the weight is constant, thus obtaining the fluorine-free oil-proof paper based on physical blocking.
  9. 9. The method for preparing fluorine-free oil-proof paper based on physical plugging according to claim 8, wherein the pressing pressure of the multifunctional pressing machine is 0.2-0.4MPa.
  10. 10. The method for preparing fluorine-free oil-proof paper based on physical plugging according to claim 8, wherein the fiber broomcorn pulp is obtained by pulping bleached needle wood chemical pulp, and the beating degree of the fiber broomcorn pulp is 40-50 DEG SR.

Description

Composite filler, fluorine-free oil-proof paper based on physical plugging and preparation method of fluorine-free oil-proof paper Technical Field The invention belongs to the technical field of fluorine-free oil-proof paper, and particularly relates to a composite filler, fluorine-free oil-proof paper based on physical plugging and a preparation method thereof. Background The fried food package is in long-term in-service use and directly contacts with high-fat food, fat is very easy to permeate into packaging materials in the storage and carrying processes, sanitation and use experience of the food are affected, traditional oil-proof paper is mostly dependent on fluorine-containing compounds to endow oil-repellent effect, but fluorine-containing materials are widely concerned in environmental persistence and potential health risks, along with the continuous popularization of food safety regulations and green and sustainable packaging concepts, fluorine-free oil-proof paper which does not contain fluorine compounds and can be safely contacted with the food gradually becomes an important development direction in the field of fried food packaging bags. At present, the preparation mode of the fluorine-free oil-proof paper mainly focuses on introducing fluorine-free oil-proof agent on the surface of paper base materials, and forms a continuous coating on the surface of the paper by means of coating, sizing and the like so as to prevent grease from penetrating into the paper, however, the fluorine-free oil-proof paper of the coating type often has the problem that the coating is easy to damage in the folding, friction or compression process, so that the coating is subjected to microcracking, local abrasion or structural damage, the continuity of the coating is weakened, grease is permeated along the damaged part, and the oil-proof performance is obviously reduced along with the use process. Therefore, how to construct a stable and durable oil-proof structure in a paper-based material without depending on a surface coating, so that good oil-proof performance can be maintained under repeated friction and folding conditions, and the method is a core technical problem to be solved in the field of fluorine-free oil-proof paper. Disclosure of Invention The invention aims to provide a composite filler, fluorine-free oil-proof paper based on physical blocking and a preparation method thereof, which are matched with each other in a paper base pore by carrying out cooperative design on montmorillonite and nanocellulose, so that the migration process of grease in the paper base is effectively blocked, the oil-proof effect taking structural blocking as a main factor is realized, and the packaging application requirements on safety, environmental protection and use reliability are met. The aim of the invention can be achieved by the following technical scheme: the invention provides a composite filler, which is prepared through the following steps: And (3) placing the chitosan modified montmorillonite, the alkyl amidated nanocellulose and deionized water into a reaction kettle, reacting for 4-6 hours at 50-60 ℃, centrifugally collecting the lower-layer solid, washing, and vacuum drying to constant weight to obtain the composite filler. Further, the dosage ratio of the chitosan modified montmorillonite, the alkyl amidated nanocellulose and the deionized water is 40-60:20-30:600-800. Further, the preparation process of the chitosan modified montmorillonite comprises the following steps: placing montmorillonite and deionized water into a reaction kettle, performing ultrasonic dispersion for 1-2h at 25-35 ℃, adding a mixed solution prepared from chitosan and glacial acetic acid with the concentration of 2wt%, reacting for 20-24h at 50-60 ℃, filtering, washing a filter cake with deionized water until the pH value of the deionized water is 7, and performing vacuum drying until the weight is constant to obtain the chitosan modified montmorillonite. Further, the dosage ratio of montmorillonite, chitosan, glacial acetic acid and deionized water is 60-80g:10-15g:600-800mL:1-1.5L. Further, the preparation process of the alkyl amidated nanocellulose comprises the following steps: And (3) placing the dodecyl amine and the absolute ethyl alcohol into a reaction kettle, stirring for 10-20min at 25-35 ℃, adding the carboxyl-rich nanocellulose suspension, reacting for 4-6h at the same stirring speed at 60-80 ℃, centrifuging, collecting the lower-layer solid, washing, and freeze-drying to constant weight to obtain the alkyl amidated nanocellulose. Further, the dosage ratio of the dodecyl amine, the carboxyl-rich nanocellulose suspension and the absolute ethyl alcohol is 10-20g:2-3L:100-200mL. Further, the preparation process of the carboxyl-rich nanocellulose suspension is as follows: and (3) placing TEMPO nanocellulose, a citric acid solution with the concentration of 1mol/L and deionized water into a reaction kettle, reacting for 1-3 hours