阅读说明：本技术 一种用于塑料、涂料的改性膨润土 (Modified bentonite for plastics and paint ) 是由 韦明 于 2020-06-12 设计创作，主要内容包括：本发明公开了一种用于塑料、涂料的改性膨润土,将膨润土粉碎后,加入水溶解,再加入二乙基二硫代氨基甲酸钠、乙二胺四乙酸和聚丙烯酰胺组成的除杂试剂搅拌均匀,静置,过滤,得膨润土浆料；向膨润土浆料中加入三聚氰胺、淀粉、菜油脂肪酸烷醇酰胺硼酸酯和咪唑啉型磷酸酯钠盐组成的复配改性剂,混合搅拌均匀,得改性膨润土浆料；再输送至表面改性机,再加入壳聚糖、肉桂醛和苄基二甲基十六烷基氯代铵组成的抗菌剂进行二次改性；再经过压滤机脱水,再经干燥,粉碎,制得改性膨润土。本发明制得的改性膨润土不仅具有很好的分散性及加工性能,与塑料、涂料具有很好的相容性,两者之间界面的结合力增强,且具有很好的阻燃性能及抗菌抑菌性能。(The invention discloses modified bentonite for plastics and coatings, which is prepared by crushing bentonite, adding water for dissolving, adding an impurity removal reagent consisting of sodium diethyldithiocarbamate, ethylene diamine tetraacetic acid and polyacrylamide, uniformly stirring, standing and filtering to obtain bentonite slurry; adding a compound modifier consisting of melamine, starch, rape oil fatty acid alkanolamide borate and imidazoline type phosphate sodium salt into the bentonite slurry, and uniformly mixing and stirring to obtain modified bentonite slurry; then conveying the mixture to a surface modifying machine, and adding an antibacterial agent consisting of chitosan, cinnamyl aldehyde and benzyldimethylhexadecylammonium chloride for secondary modification; and dehydrating by a filter press, drying and crushing to obtain the modified bentonite. The modified bentonite prepared by the invention has good dispersibility and processability, good compatibility with plastics and coatings, enhanced bonding force of interfaces between the plastics and the coatings, and good flame retardant property and antibacterial property.)

1. A modified bentonite for plastics and coatings is characterized in that: the preparation of the modified bentonite comprises the following steps:

s1: crushing bentonite, adding water for dissolving, adding an impurity removal reagent consisting of sodium diethyldithiocarbamate, ethylene diamine tetraacetic acid and polyacrylamide, uniformly stirring, standing, and filtering to obtain bentonite slurry;

s2: adding a compound modifier consisting of melamine, starch, rape oil fatty acid alkanolamide borate and imidazoline type phosphate sodium salt into the bentonite slurry, and uniformly mixing and stirring to obtain modified bentonite slurry;

s3: conveying the modified bentonite slurry to a surface modifying machine, and adding an antibacterial agent consisting of chitosan, cinnamaldehyde and benzyldimethylhexadecylammonium chloride for secondary modification;

s4: and dehydrating the slurry subjected to secondary modification by using a filter press, drying and crushing to obtain the modified bentonite.

2. The modified bentonite for plastics and coatings according to claim 1, wherein: the addition amount of the impurity removal reagent is 2-4% of the mass of the bentonite.

3. The modified bentonite for plastics and coatings according to claim 2, wherein: the mass ratio of the sodium diethyldithiocarbamate to the ethylene diamine tetraacetic acid to the polyacrylamide is 1-3:1-3: 5-10.

4. The modified bentonite for plastics and coatings according to claim 1, wherein: the addition amount of the compound modifier is 3-5% of the dry weight of the bentonite in the slurry.

5. The modified bentonite for plastics and coatings according to claim 4, wherein: the mass ratio of the melamine to the starch to the rape oil fatty acid alkanolamide borate to the imidazoline type sodium phosphate is 3-5:6-10:1-3: 1-3.

6. The modified bentonite for plastics and coatings according to claim 1, wherein: the addition amount of the antibacterial agent is 1-3% of the dry weight of the bentonite in the slurry.

7. The modified bentonite for plastics and coatings according to claim 6, wherein: the mass ratio of the chitosan, the cinnamaldehyde and the benzyldimethylhexadecylammonium chloride in the antibacterial agent is 3-5:1-3: 0.5-1.5.

8. The modified bentonite for plastics and coatings according to claim 1, wherein: the drying is realized by adopting a pulse airflow dryer; the feeding speed of the pulse airflow dryer is 120-180kg/h, the drying temperature is 80-100 ℃, and the air speed is 15-20 m/s.

Technical Field

The invention relates to the technical field of preparation of inorganic nonmetallic minerals, in particular to modified bentonite for plastics and coatings.

Background

The bentonite is a non-metal mineral product with montmorillonite as a main mineral component, and the montmorillonite structure is 2: a type 1 crystal structure. The bentonite is one of the clay minerals with the widest application range and higher economic value at present due to the special water absorbability, water plasticity, caking property, stronger ion exchange property and the like. The bentonite can be used as binder, suspending agent, thickener, thixotropic agent, and flocculation agent

The catalyst is used in metallurgical, mechanical, petroleum, chemical, polymer material, environment protection and other fields.

In the plastic and paint industries, the bentonite not only can play a role in enhancing and improving the adhesion, but also can improve the water resistance, flame retardance, insulation, wear resistance, corrosion resistance and other properties of the product. However, the bentonite has hydrophilic and oleophobic surfaces, is strong in polarity, has a large comparative area and high surface free energy, and is easy to agglomerate in an organic system, so that the bentonite is difficult to uniformly disperse in plastic and coating base materials, the agglomeration phenomenon among particles is easy to occur, the bonding force between the bentonite and the plastic and coating base materials is poor, interface defects are easy to cause, the bentonite is easy to fall off, and the material performance is reduced. Therefore, it is necessary to modify the surface of bentonite to improve the dispersibility and processability of bentonite in plastics and coating systems and to improve the binding force between bentonite and plastics and coating substrates, thereby maximizing the material properties. With the increasing awareness of people on health and environmental protection, the requirements of bacteriostasis and sterilization are provided for coating plastic products which are frequently contacted in daily life, so that the demand of improving the antibacterial property of bentonite is the demand of the current market.

Disclosure of Invention

The invention provides a modified bentonite for plastics and coatings aiming at the problems. The modified bentonite prepared by the scheme of the invention has good dispersibility and processability, good compatibility with plastics and coatings, and strong bonding force of an interface between the plastics and the coatings, and the modified bentonite has good flame retardant property and antibacterial and bacteriostatic properties.

In order to achieve the above purpose, the technical scheme adopted by the invention is as follows:

a modified bentonite for plastics and paint is prepared through the following steps:

s1: crushing bentonite, adding water for dissolving, adding an impurity removal reagent consisting of sodium diethyldithiocarbamate, ethylene diamine tetraacetic acid and polyacrylamide, uniformly stirring, and standing to obtain bentonite slurry;

s2: adding a compound modifier consisting of melamine, starch, rape oil fatty acid alkanolamide borate and imidazoline type phosphate sodium salt into the bentonite slurry, and uniformly mixing and stirring to obtain modified bentonite slurry;

s3: conveying the modified bentonite slurry to a surface modifying machine, and adding an antibacterial agent consisting of chitosan, cinnamaldehyde and benzyldimethylhexadecylammonium chloride for secondary modification;

s4: and dehydrating the slurry subjected to secondary modification by using a filter press, drying and crushing to obtain the modified bentonite.

Furthermore, the addition amount of the impurity removal reagent is 2-4% of the mass of the bentonite.

Further, the mass ratio of the sodium diethyldithiocarbamate to the ethylene diamine tetraacetic acid to the polyacrylamide is 1-3:1-3: 5-10.

Further, the addition amount of the compound modifier is 3-5% of the dry weight of the bentonite in the slurry.

Further, the mass ratio of the melamine to the starch to the rape oil fatty acid alkanolamide borate to the imidazoline type phosphate sodium salt is 3-5:6-10:1-3: 1-3.

Further, the addition amount of the antibacterial agent is 1-3% of the dry weight of the bentonite in the slurry.

Further, the mass ratio of the chitosan, the cinnamaldehyde and the benzyldimethylhexadecylammonium chloride in the antibacterial agent is 3-5:1-3: 0.5-1.5.

Further, the drying is drying by adopting a pulse airflow dryer; the feeding speed of the pulse airflow dryer is 120-180kg/h, the drying temperature is 80-100 ℃, and the air speed is 15-20 m/s.

Compared with the prior art, the invention has the advantages and beneficial effects that:

1. according to the method, the bentonite is modified by adopting the compound modifier consisting of melamine, starch, rape oil fatty acid alkanolamide borate and imidazoline type phosphate sodium salt to form an organic-inorganic hybrid network structure, so that the compatibility of the bentonite with plastics and coatings can be improved, the binding force between materials is enhanced, the dispersibility and the processability of the cloud bentonite are improved, the oil absorption value of the bentonite is reduced, and meanwhile, the added modifier forms a P-N-B flame retardant system to improve the flame retardance of the bentonite.

2. According to the method, the bentonite is subjected to secondary modification by an antibacterial agent consisting of chitosan, cinnamaldehyde and benzyldimethylhexadecylammonium chloride, so that the antibacterial and bacteriostatic performance of the bentonite can be improved, and the bentonite can be applied to plastics and coatings to further improve the antibacterial and bacteriostatic performance of products, is in line with the pursuit of modern people on antibacterial products, and has a wide market prospect.

3. According to the method, before modification, the bentonite is subjected to impurity removal treatment by sodium diethyldithiocarbamate, ethylene diamine tetraacetic acid and polyacrylamide, so that metals such as iron, cobalt and the like in the bentonite can be removed, the purity of the bentonite is improved, and the stability of the product is improved.

4. The method adopts the pulse airflow dryer to dry the bentonite, so that the drying and heating are uniform, the efficiency is high, the modifier can be better wrapped on the surface of the bentonite, and the dispersion of the bentonite is facilitated.

Detailed Description

The present invention will be described in further detail with reference to specific embodiments. It should be emphasized that the following description is merely exemplary in nature and is not intended to limit the scope of the invention or its application.