阅读说明：本技术 一种含锡酸根离子的钴、锌杂化片状交叉zif阻燃剂及其制备方法 (Cobalt and zinc hybrid flaky crossed ZIF flame retardant containing stannate ions and preparation method thereof ) 是由 徐文总 李武 程传明 赵永朴 张雪敏 于 2019-08-22 设计创作，主要内容包括：本发明属于阻燃抑烟领域,具体涉及一种含锡酸根离子的钴、锌杂化片状交叉ZIF阻燃剂,所述阻燃剂是由锡酸根离子通过共价键作用力被吸附在钴、锌杂化片状交叉ZIF材料表面得到。本发明还涉及一种上述阻燃剂的制备方法,把制备的阻燃剂添加到聚合物中形成复合材料后,在燃烧过程中,所述阻燃剂的片层结构能够起到一定的阻隔作用,且阻燃剂分解后产生的金属氧化物覆盖在聚合物材料的表面,也能起到隔离作用,同时能够催化成炭,进一步提高了阻燃效果；含锡酸根离子的钴、锌杂化片状交叉ZIF在燃烧过程中还会释放出含氮气体,从而在气相中起到一定的阻燃作用；此外,引入锡酸根离子的阻燃剂在抑烟性能上可以得到极大的改善。(The invention belongs to the field of flame retardance and smoke suppression, and particularly relates to a cobalt and zinc hybridized flaky crossed ZIF flame retardant containing stannate ions, which is obtained by adsorbing stannate ions on the surface of a cobalt and zinc hybridized flaky crossed ZIF material through a covalent bond acting force. The invention also relates to a preparation method of the flame retardant, after the prepared flame retardant is added into a polymer to form a composite material, in the combustion process, the lamellar structure of the flame retardant can play a certain role in blocking, and metal oxide generated after the flame retardant is decomposed covers the surface of the polymer material and also can play a role in blocking, and meanwhile, the flame retardant can be catalyzed to form carbon, so that the flame retardant effect is further improved; the cobalt and zinc hybridized flaky crossed ZIF containing stannate ions can release nitrogen-containing gas in the combustion process, so that a certain flame retardant effect is achieved in a gas phase; in addition, the fire retardant with stannate ions introduced can be greatly improved in smoke suppression performance.)

1. A cobalt and zinc hybrid flaky crossed ZIF flame retardant containing stannate ions is characterized in that: the flame retardant is obtained by adsorbing stannate ions on the surface of a cobalt and zinc hybrid flaky crossed ZIF material through a covalent bond acting force.

2. A method of making the stannate ion-containing cobalt, zinc hybrid platy crossed ZIF flame retardant of claim 1, comprising the steps of:

a) respectively preparing soluble zinc salt, soluble cobalt salt and 2-methylimidazole into aqueous solutions;

b) mixing the three aqueous solutions according to the molar ratio of soluble zinc salt to soluble cobalt salt to 2-methylimidazole of 1:1:16, stirring for 24 hours, centrifuging, washing with deionized water, and vacuum drying at 80 ℃ for 12 hours to prepare a cobalt-zinc hybrid flaky crossed ZIF;

c) and c) adding the product prepared in the step b) into a water solution of stannate, and treating by a coprecipitation method to obtain a precipitate, namely the cobalt and zinc hybrid flaky crossed ZIF containing stannate ions.

3. The preparation method of the stannate ion-containing cobalt-zinc hybrid platy crossed ZIF flame retardant according to claim 2, characterized in that: in the step a), the concentrations of the soluble zinc salt, the soluble cobalt salt and the 2-methylimidazole water solution are 0.05-0.075M, 0.05-0.075M and 2-2.4M respectively.

4. The preparation method of the stannate ion-containing cobalt-zinc hybrid platy crossed ZIF flame retardant according to claim 2, characterized in that: in the step a), the soluble cobalt salt and the soluble zinc salt are cobalt nitrate hexahydrate and zinc nitrate hexahydrate respectively.

5. The preparation method of the stannate ion-containing cobalt-zinc hybrid platy crossed ZIF flame retardant according to claim 2, characterized in that: the stannate in the step c) is sodium stannate, and the mass ratio of the sodium stannate to the cobalt-zinc hybrid flaky crossed ZIF is 10-20: 1.

6. The method for preparing the cobalt-zinc hybrid platy crossed ZIF containing stannate ions according to claim 2, characterized in that: the mixture coprecipitation method in the step c) comprises the following steps: the mixture was stirred at 100rpm for 4h, then centrifuged, washed with deionized water and dried under vacuum at 80 ℃ for 12 h.

Technical Field

The invention belongs to the field of flame retardance and smoke suppression, and particularly relates to a cobalt and zinc hybrid flaky crossed ZIF flame retardant containing stannate ions and a preparation method thereof.

Background

The organic polymer material has wide application in various fields such as daily life of people, national economic construction and the like, and brings great convenience to the life of human beings and the development of society. However, most organic polymer materials are easily ignited and rapidly burned, and generate a large amount of combustion heat and toxic and harmful smoke, which undoubtedly pose a great threat to human life, and thus increasing the flame retardant and smoke suppressing performance of organic polymer materials is receiving increasing attention from researchers.

Metal-organic framework Materials (MOFs), as a novel porous nanomaterial, have attracted attention in various fields such as gas storage and separation, chromatographic separation, catalysis, and flame retardancy due to their characteristics of high specific surface area, adjustability of pore size, and the like. Among them, a Zeolitic Imidazolate Framework (ZIF), which is one of the MOFs, has better thermal and chemical stability than most other kinds of MOFs. The cobalt and zinc hybridized flaky crossed ZIF is a Zn-utilizing compound²⁺、Co²⁺The cobalt-zinc hybrid flaky crossed ZIF has two flame-retardant elements of cobalt and zinc and simultaneously contains nitrogen elements, the lamellar structure of the cobalt-zinc hybrid flaky crossed ZIF can play a role in blocking in the combustion process, and the decomposed product has a function of catalyzing to form carbon.

Stannate is used as an inorganic flame retardant, is environment-friendly, and can play a certain flame-retardant and smoke-suppression role by adding a small amount of the flame retardant with stannate ions introduced.

Disclosure of Invention

The invention aims to provide a cobalt and zinc hybrid flaky crossed ZIF flame retardant containing stannate ions, which can effectively improve the flame retardant and smoke suppression performance and mechanical property of a polymer material.

In order to achieve the purpose, the invention adopts the technical scheme that: the cobalt and zinc hybridized flaky crossed ZIF flame retardant containing stannate ions is obtained by adsorbing stannate ions on the surface of a cobalt and zinc hybridized flaky crossed ZIF material through the action force of covalent bonds.

The invention also aims to provide a preparation method of the cobalt and zinc hybrid sheet crossed ZIF flame retardant containing stannate ions, which has the advantages of easily available raw materials, simple preparation method, low cost, environmental friendliness, and capability of remarkably improving the flame retardance, smoke suppression and mechanical properties of the polymer by integrating coacervate flame retardance and gas-phase flame retardance.

In order to achieve the purpose, the invention adopts the technical scheme that: a preparation method of the cobalt and zinc hybrid flaky crossed ZIF flame retardant containing stannate ions comprises the following steps:

a) respectively preparing soluble zinc salt, soluble cobalt salt and 2-methylimidazole into aqueous solutions;

b) mixing the three aqueous solutions according to the molar ratio of soluble zinc salt to soluble cobalt salt to 2-methylimidazole of 1:1:16, stirring for 24 hours, centrifuging, washing with deionized water, and vacuum drying at 80 ℃ for 12 hours to prepare a cobalt-zinc hybrid flaky crossed ZIF;

c) and c) adding the product prepared in the step b) into a water solution of stannate, and treating by a coprecipitation method to obtain a precipitate, namely the cobalt and zinc hybrid flaky crossed ZIF containing stannate ions.

By adopting the scheme, after the cobalt and zinc hybridized flaky crossed ZIF flame retardant containing stannate ions is added into a polymer to form a composite material, in the combustion process, the lamellar structure of the flame retardant can play a certain role in blocking, and metal oxides generated after the flame retardant is decomposed cover the surface of the polymer material, so that the isolation function can be played, and meanwhile, the flame retardant can be catalyzed into charcoal, so that the flame retardant effect is further improved; the cobalt and zinc hybridized flaky crossed ZIF containing stannate ions can release nitrogen-containing gas in the combustion process, so that a certain flame retardant effect is achieved in a gas phase; in addition, the fire retardant with stannate ions introduced can be greatly improved in smoke suppression performance. Therefore, the flame retardant can greatly improve the flame retardant and smoke suppression performance of the polymer material.

Specifically, in the step a), the concentrations of a soluble zinc salt, a soluble cobalt salt and a 2-methylimidazole aqueous solution are 0.05-0.075M, 0.05-0.075M and 2-2.4M respectively; the soluble cobalt salt and the soluble zinc salt are cobalt nitrate hexahydrate and zinc nitrate hexahydrate, respectively.

The stannate in the step c) is sodium stannate, and the mass ratio of the sodium stannate to the cobalt-zinc hybrid flaky crossed ZIF is 10-20: 1. The coprecipitation method of the mixture comprises the following steps: the mixture was stirred at 100rpm for 4h, then centrifuged, washed with deionized water and dried under vacuum at 80 ℃ for 12 h.

Detailed Description

The technical solution of the present invention is further described below with reference to examples.