阅读说明：本技术 一种用于纯化环硅氧烷的固载催化剂 (Immobilized catalyst for purifying cyclosiloxane ) 是由 张年运 王海栋 廖立 胡应如 欧阳文武 于 2020-04-22 设计创作，主要内容包括：本发明涉及一种用于纯化环硅氧烷的固载催化剂,所述固载催化剂是改性有机二价金属和有机锡的混合物,掺杂载体所得。将其负载到特定的载体中,制成固载催化剂,然后将固载催化剂均匀地填充至硅胶柱内,将待纯化的环硅氧烷通过该硅胶柱。经发现,经本发明中固载催化剂纯化过后的环硅氧烷,仅含有痕量的线性聚硅氧烷,或者不含有线性聚硅氧烷,经处理后得到的环硅氧烷含量可以达到99.99％以上。(The invention relates to an immobilized catalyst for purifying cyclosiloxane, which is obtained by doping a carrier with a mixture of modified organic divalent metal and organic tin. Loading the catalyst into a specific carrier to prepare an immobilized catalyst, then uniformly filling the immobilized catalyst into a silica gel column, and passing the cyclosiloxane to be purified through the silica gel column. The cyclosiloxane purified by the immobilized catalyst of the invention only contains trace linear polysiloxane or does not contain linear polysiloxane, and the content of the cyclosiloxane obtained after treatment can reach more than 99.99 percent.)

1. An immobilized catalyst for purifying cyclosiloxane, which is characterized in that the immobilized catalyst is a mixture of modified organic divalent metal and organic tin and is obtained by loading the mixture on a carrier; the modified organic divalent metal is obtained by reacting monoalkyl oxidized divalent metal salt with fatty acid.

2. The supported catalyst for purifying cyclosiloxane as claimed in claim 1, wherein the organotin is selected from any one of dibutyltin di-isooctyl maleate, dibutyltin di-laurate, dibutyltin di-acetate or dibutyltin di-octanoate.

3. The supported catalyst for purifying cyclosiloxanes of claim 1, wherein the modified organic divalent metal is obtained by a preparation method comprising the steps of:

mixing the monoalkyl oxidation divalent metal salt with fatty acid, stirring at the temperature of 100-120 ℃, dividing water, and then carrying out hot filtration to obtain the modified organic divalent metal catalyst.

4. The supported catalyst for the purification of cyclosiloxanes according to claim 1, wherein the alkyl group is selected from one or more of butyl, hexyl, octyl, decyl, dodecyl, tetradecyl or hexadecyl.

5. The supported catalyst for purifying cyclosiloxane as claimed in claim 1, wherein the mixture of the modified organic divalent metal and the organotin has a ratio of the amount of the modified organic divalent metal to the amount of the organotin in the range of 1:5 to 10.

6. The supported catalyst for purifying cyclosiloxane of claim 1, wherein said divalent metal is selected from any one of tin or zinc.

7. The supported catalyst for purifying cyclosiloxane as claimed in claim 1, wherein said supported catalyst for purifying cyclosiloxane is prepared by the steps of:

physically mixing the modified organic divalent metal and the organic tin, grinding to obtain a mixture, dissolving the mixture in an organic solvent, adding the carrier into the mixture, carrying out reflux reaction, cooling, filtering, collecting the solid, and drying to obtain the immobilized catalyst for purifying the cyclosiloxane.

8. The supported catalyst for purifying cyclosiloxane of claim 7, wherein said support is selected from the group consisting of activated carbon, molecular sieves, or diatomaceous earth; the weight ratio of the mixture to the carrier is 1:50-1: 80.

9. A method for purifying cyclosiloxane, characterized in that the immobilized catalyst of any one of claims 1 to 9 is uniformly mixed with silica gel to form a silica gel column, the cyclosiloxane to be purified is passed through the silica gel column, and the effluent is collected to obtain the purified cyclosiloxane.

10. The method according to claim 9, wherein the mass ratio of the supported catalyst, silica gel and cyclosiloxane to be purified is 5 to 10: 30-50: 8-12.

Technical Field

The invention belongs to the field of organosilicon ring body treatment, and particularly relates to an immobilized catalyst for purifying cyclosiloxane.

Background

The cyclosiloxane has a main chain with silicon atoms and oxygen atoms which are alternately arranged, and organic groups are connected on the silicon atoms, so that the structure endows the cyclosiloxane with unique properties such as high and low temperature resistance, weather resistance, aging resistance, electric insulation, ozone resistance, hydrophobicity, physiological inertia and the like, which are incomparable with other organic macromolecules. Therefore, cyclosiloxane has been widely applied in the aspects of aerospace, electronic and electric appliances, chemical industry, machinery, construction, transportation, medical treatment and public health, agriculture and the like, and becomes an irreplaceable novel high polymer material in national economy. In the above industries, cyclosiloxanes are specifically used to include: stabilization of polyurethane foams, use as emulsifiers, barrier coatings, and the like.

For example, the german laid-open patent DE1493380 describes cyclosiloxanes with polyether modifications, their preparation and use as wetting agents, in particular for aqueous coatings, adhesives, printing inks, impregnating solutions and emulsions.

Likewise, the german laid-open patent DE19631227 claims the use of cyclosiloxanes with polyether residues as foam stabilizers, in particular for polyurethane foams. The economic advantage of cyclosiloxanes compared to linear siloxanes is highlighted by the fact that the quantity of chlorotrimethylsilane produced in the silane synthesis by the Rochow method is only 2% to 4%, considering that the starting material for the production of cyclosiloxanes does not require any chlorotrimethylsilane.

In the application of the above fields, the effect of the cyclosiloxane is not ideal, and the purity of the cyclosiloxane is inseparable. At present, the preparation method of cyclosiloxane contains partial linear polysiloxane, and the structures and polarities of the two are similar, so that the linear polysiloxane is difficult to completely separate from the cyclosiloxane product, the purity of the obtained finished product is reduced, and the use effect and the user experience of the product in the application field are further influenced.

In the prior art, many patents are available on the preparation method and application of cyclosiloxane, for example, CN103450249A discloses a method for refining methyl cyclosiloxane; CN103923464A discloses the use of this cyclosiloxane in liquid silicone rubber; CN105085567A discloses a multifunctional group co-substituted cyclosiloxane; CN103558315A discloses a method for preparing cyclosiloxane-substituted polysiloxane compounds. However, none of the above patents disclose an effective removal method for linear polysiloxanes in cyclosiloxanes. It is expected that the effect of the cyclic siloxane containing a linear polysiloxane on the product is to be improved.

In view of the above, it is desirable to find a method for removing linear siloxanes from cyclosiloxanes, so as to further improve the purity of cyclosiloxanes, thereby overcoming the above-mentioned drawbacks.

Disclosure of Invention

The invention aims to provide an immobilized catalyst for purifying cyclosiloxane, which can effectively remove linear polysiloxane in cyclosiloxane products, so that final cyclosiloxane products contain only trace linear polysiloxane and even do not contain linear polysiloxane, thereby effectively improving the product quality. The immobilized catalyst for purifying cyclosiloxane disclosed by the invention has the advantages of wide raw material source, easiness in preparation and wider industrial prospect.

The present invention is realized by the following technical means.

An immobilized catalyst for purifying cyclosiloxane, which is characterized in that the immobilized catalyst is a mixture of modified organic divalent metal and organic tin and is obtained by loading the mixture on a carrier; the modified organic divalent metal is obtained by reacting monoalkyl oxidized divalent metal salt with fatty acid.

The molecular formula of the monoalkyl oxidized divalent metal salt is R₂X₂O₃(ii) a The structural formula is as follows: R-X (O) -O- (O) X-R. Wherein R is an alkyl group. Examples in the present invention include, but are not limited to, one or more of butyl, hexyl, octyl, decyl, dodecyl, tetradecyl, or hexadecyl; x is a divalent metal, including but not limited to metallic tin or zinc in the present invention.

Further, the organic tin is selected from any one of dibutyl tin di-isooctyl maleate, dibutyl tin di-laurate, dibutyl tin di-acetate and dibutyl tin di-octoate.

Further, the preparation method of the modified organic divalent metal comprises the following steps:

mixing the monoalkyl oxidation divalent metal salt with fatty acid, stirring at the temperature of 100-120 ℃, dividing water, and then carrying out hot filtration to obtain the modified organic divalent metal catalyst.

The synthetic route of the preparation process is shown as follows:

wherein X represents a divalent metal, and R1 represent an alkyl group. The chemical equation is a coupling reaction, which generates a water byproduct, so the reaction needs to be drained in time to promote the reaction to move in a positive direction.

Further, the alkyl group is selected from one or more of butyl, hexyl, octyl, decyl, dodecyl, tetradecyl or hexadecyl.

Further, in the mixture of the modified organic divalent metal and the organic tin, the mass ratio of the modified organic divalent metal to the organic tin is 1: 5-10.

Further, the divalent metal is selected from any one of tin and zinc.

Further, the fatty acid is selected from caproic acid, caprylic acid, capric acid, lauric acid or myristic acid.

Further, the preparation method of the immobilized catalyst for purifying cyclosiloxane comprises the following steps:

physically mixing the modified organic divalent metal and the organic tin, grinding to obtain a mixture, dissolving the mixture in an organic solvent, adding the carrier into the mixture, carrying out reflux reaction, cooling, filtering, collecting the solid, and drying to obtain the immobilized catalyst for purifying the cyclosiloxane.

Further, the organic solvent is selected from toluene, xylene, trimethylbenzene, chlorobenzene, dichlorobenzene or trichlorobenzene.

Further, the carrier is selected from activated carbon, molecular sieve or diatomite.

Further, the particle size of the mixture obtained by the grinding is 0.5 to 10 μm, preferably 2 to 5 μm.

Further, the weight ratio of the mixture to the carrier is 1:50-1: 80.

The invention also provides a method for purifying cyclosiloxane, which is to mix the immobilized catalyst and silica gel uniformly to form a silica gel column, pass the cyclosiloxane to be purified through the silica gel column, and collect the effluent to obtain the purified cyclosiloxane.

Preferably, wherein the mass ratio of the catalyst-immobilized catalyst, silica gel and cyclosiloxane to be purified is 5-10: 30-50: 1-2.

Furthermore, the ratio of height to diameter of the silica gel column is 4-6:1, and the flow rate of the cyclosiloxane flowing through the silica gel column is 0.5-1.0 BV/h.

The invention has the following beneficial effects:

the invention adopts the mixture of modified organic divalent metal and organic tin as a catalyst, and the catalyst is loaded into a specific carrier to prepare an immobilized catalyst, then the immobilized catalyst is uniformly filled into a silica gel column, and cyclosiloxane to be purified passes through the silica gel column. It has surprisingly been found that the purified cyclosiloxane contains only traces of linear polysiloxanes or no linear polysiloxanes. This effect may be obtained because the modified organic divalent metal in the present invention is an organic divalent metal compound having an organic polar group, which has a synergistic effect when mixed with organotin. Specifically, the modified divalent organic metal and the organotin both have a similar alkyl chain structure and can be uniformly mixed, and the modified divalent organic metal has a polar group of an ester group, can be well adhered to a silica gel column, and has a good affinity adsorption effect on polar groups (such as hydroxyl groups and the like) on linear polysiloxane, while hardly having any adsorption capability on cyclic siloxane having no polar groups, so that the contact time and area of the organotin and the linear polysiloxane are greatly increased. Therefore, the immobilized catalyst reported by the invention can efficiently and selectively adsorb linear polysiloxane impurities, but cannot cause obvious quality damage to cyclosiloxane. Therefore, the cyclosiloxane can be further purified as an industrial means.

Drawings

FIG. 1 is a chromatogram showing the contents of the respective components of the cyclosiloxane to be purified according to the present invention.

FIG. 2 is a chromatogram showing the contents of each component of the purified cyclosiloxane treated with the supported catalyst for purifying the cyclosiloxane in example 1.

FIG. 3 is a chromatogram showing the contents of each component of the purified cyclosiloxane treated with the supported catalyst for purifying cyclosiloxane in comparative example 1.

Detailed Description

The present invention is further illustrated by the following specific examples, which are not intended to limit the invention in any way. The starting materials described in the examples of the present invention are commercially available and, unless otherwise specified, the starting materials and methods employed are those conventional in the art.

The cyclosiloxanes to be purified in the present invention were obtained from the applicant's production plant, wherein the total amount of each cyclosiloxane was 97.78455% by mass and the total amount of each short strand was 9% by mass

Wherein the used dibutyl tin di-isooctyl maleate, dibutyl tin di-laurate, dibutyl tin di-acetate or dibutyl tin di-caprylate are purchased from Shenzhen Heideli chemical engineering Co., Ltd;

the used activated carbon is purchased from Jieli activated carbon Limited liability company in Huaibei city and is solvent recovery type activated carbon in coal activated carbon series;

the molecular sieve is purchased from New Orli adsorption materials, Inc. of Huzhou, and has a model of CMS-20;

the diatomite is purchased from Hebei Xin Xu mineral products Limited company, the silicon dioxide content of the diatomite is 95 percent, and the mesh number of the diatomite is 200 meshes;

the fatty acid used was purchased from a pacific source;

monobutyl tin oxide, monooctyl tin oxide is purchased from AlfaAlsar, monohexyl zinc oxide, monotetradecyl zinc oxide is purchased from Sigma-Aldrich.

Preparation example 1

The preparation method of the modified organic divalent metal 1 comprises the following steps: 50mmol of monobutyl tin oxide and 200mmol of caproic acid are mixed in a 500ml three-necked bottle, stirred for 3 hours at 100 ℃, and generated water is separated in time by adopting a water separator and then filtered when the mixture is hot, thus obtaining the modified organic divalent metal 1.

Preparation example 2

The preparation method of the modified organic divalent metal 2 comprises the following steps: 50mmol of monotetradecyl zinc oxide and 220mmol of caprylic acid are mixed in a 500ml three-necked flask, stirred for 3 hours at 120 ℃, and generated water is separated in time by adopting a water separator and then filtered when the mixture is hot, so that the modified organic divalent metal 2 is obtained.

Preparation example 3

The preparation method of the modified organic divalent metal 3 comprises the following steps: 50mmol of monooctyltin oxide and 210mol of dodecanoic acid are mixed in a 500ml three-necked bottle, stirred for 3 hours at 110 ℃, and generated water is separated in time by adopting a water separator and then filtered when the mixture is hot, thus obtaining the modified organic divalent metal 3.

Preparation example 4

The preparation method of the modified organic divalent metal 4 comprises the following steps: 50mmol of monohexyl zinc oxide and 200mmol of myristic acid are mixed in a 500ml three-necked bottle, stirred for 3 hours at 100 ℃, and generated water is separated in time by adopting a water separator and then filtered while hot to obtain the modified organic divalent metal 4.

Example 1

The preparation method of the supported catalyst 1 for purifying cyclosiloxane is as follows: mixing modified organic divalent metal 1 and dibutyltin di-myristate, wherein the mass parts of the modified organic divalent metal 1 and dibutyltin di-laurate are 1 part and 10 parts respectively, grinding the mixture to the particle size of about 2 mu m, dissolving the mixture into 500 parts by mass of chlorobenzene, adding carrier activated carbon of which the mass part is 50 times that of the mixture of the modified organic divalent metal 1 and dibutyltin di-laurate, reacting for 3 hours under a reflux condition, cooling a system, filtering, collecting solids, and drying in an oven at 40 ℃ for 24 hours to obtain the immobilized catalyst 1 for purifying cyclosiloxane.

Example 2

The preparation method of the supported catalyst 2 for purifying cyclosiloxane is as follows: mixing modified organic divalent metal 2 and dibutyltin di-acetate, wherein the mass parts of the modified organic divalent metal 2 and the dibutyltin di-acetate are respectively 1 part and 5 parts, grinding the mixture until the particle size is about 5 mu m, dissolving the mixture into 500 parts of dichlorobenzene, adding a carrier molecular sieve of which the mass part is 80 times that of the mixture of the modified organic divalent metal 2 and the dibutyltin di-acetate, reacting for 3 hours under a reflux condition, cooling a system, filtering, collecting solids, and drying in an oven at 40 ℃ for 24 hours to obtain the immobilized catalyst 2 for purifying cyclosiloxane.

Example 3

The preparation method of the supported catalyst 3 for purifying cyclosiloxane is as follows: mixing modified organic divalent metal 3 and dibutyltin di-octoate, wherein the mass parts of the modified organic divalent metal 3 and the dibutyltin di-octoate are respectively 1 part and 8 parts, grinding the mixture until the particle size is about 5 mu m, dissolving the mixture into 500 parts by mass of toluene, adding a carrier molecular sieve of which the mass part is 65 times that of the mixture of the modified organic divalent metal 3 and the dibutyltin di-octoate, reacting for 3 hours under a reflux condition, cooling a system, filtering, collecting solids, and drying in an oven at 40 ℃ for 24 hours to obtain the immobilized catalyst 3 for purifying cyclosiloxane.

Example 4

The preparation method of the supported catalyst 4 for purifying cyclosiloxane is as follows: mixing modified organic divalent metal 4 and dibutyltin di-isooctyl maleate, wherein the mass parts of the modified organic divalent metal 4 and dibutyltin di-isooctyl maleate are respectively 1 part and 8 parts, grinding the mixture until the particle size is about 3 mu m, dissolving the mixture into 500 parts of dimethylbenzene, adding carrier diatomite which is 80 times the mass part of the mixture of the modified organic divalent metal 4 and dibutyltin di-isooctyl maleate, reacting for 3 hours under a reflux condition, cooling a system, filtering, collecting solids, and drying for 24 hours in an oven at 40 ℃ to obtain the solid-supported catalyst 4 for purifying cyclosiloxane.

Example 5

Example 5 the same raw material types, raw material ratios and preparation methods as those of example 1 were used, except that the particle size of the mixture obtained by grinding was 10 μm.

Example 6

Example 6 the same raw material types, raw material ratios and preparation methods as example 1, with the only difference that the weight ratio of the mixture to the carrier is 1: 35.

Example 7

Example 7 the same raw material types, raw material ratios and preparation methods as example 1, with the only difference that the weight ratio of the mixture to the carrier is 1: 90.

Comparative example 1

Comparative example 1 the same raw material types, raw material ratios and preparation methods as those of example 1 were used, except that comparative example 1 did not contain the modified organic divalent metal 1, and an equal amount of dibutyltin di-laurate was used instead.

Comparative example 2

Comparative example 2 the same raw material type, raw material ratio and preparation method as those of example 1, except that comparative example 2 does not contain dibutyltin di-laurate and is replaced with the same amount of the modified organic divalent metal 1.

Application example

The supported catalyst samples obtained in examples 1 to 7 and comparative examples 1 to 3 were tested for their removal effect on linear polysiloxanes in cyclosiloxanes.

The method comprises the following steps:

the supported catalysts prepared in the above examples and comparative examples, i.e. the supported catalysts used for purifying cyclosiloxane, were mixed with 300g of silica gel with 200 meshes and 300 meshes, respectively, 50g of each supported catalyst was uniformly mixed with 300g of silica gel, and then the mixture was packed into a plurality of glass columns with 20mm inner diameter and 80mm length, respectively, with a spatula to form a silica gel column, and was compacted until the height of the silica gel in the silica gel column did not change. Then a sample of the cyclosiloxane to be purified, having a total weight of 80g, was passed through a silica gel column by means of a peristaltic pump at a flow rate of about 0.5BV/h, the temperature of the silica gel column being controlled at 20-30 ℃. The purified cyclosiloxane passed through the silica gel column was then collected and sampled and the fractions of the collected cyclosiloxane were analyzed using a chromatograph model agilent technologies7890BGCSystem (column HP-1). Wherein each specific component of the cyclosiloxane to be purified, the purified cyclosiloxane treated with the supported catalyst for purifying the cyclosiloxane in example 1, and the purified cyclosiloxane treated with the supported catalyst for purifying the cyclosiloxane in comparative example 1 is shown in table 1.

Table 1:

wherein D3-17 represents cyclosiloxane, ring body for short, the structural general formula of the cyclosiloxane is a cyclic polysiloxane structure with the repeating unit of the following structure, D3-10 respectively corresponds to the structural formula when n is 3-10:

l2OH-L10OH represent a mitochondria, the general structural formula of which is a linear polysiloxane structure with the following repeating unit, L2OH-L10OH respectively correspond to the structural formula when n is 2-10:

as can be seen from Table 1, the cyclosiloxanes treated with the supported catalyst for purifying cyclosiloxanes of example 1 contained little or only trace amounts of the linear polysiloxanes of L2OH-L10OH in the final cyclosiloxane product. And the content of L2OH-L10OH contained in the cyclosiloxane treated by the immobilized catalyst for purifying the cyclosiloxane in the example 1 is obviously reduced compared with that of L2OH-L10OH in the comparative example 1 with a corresponding structure; meanwhile, D3-17 in the cyclosiloxane treated with the supported catalyst for purifying cyclosiloxane of example 1 was not significantly reduced relative to the corresponding structure of comparative example 1; or at the same level; in particular, the content of partial rings is also increased, for example D5/D6. This shows that the cyclosiloxane treated by the technical scheme of example 1 can effectively remove linear siloxane mixed in the cyclosiloxane, and meanwhile, the linear siloxane does not cause obvious loss to the target product, and the amount of partial ring bodies is increased because the short linear bodies generate ring closure reaction under the action of the catalyst to generate partial ring bodies.

The cyclosiloxanes to be purified were treated by the same treatment method using the samples of examples 2 to 7 and comparative examples 2 to 3, respectively, and the contents of the cyclic bodies and the short-chain bodies obtained after the treatment are shown in Table 2.

Table 2:

as can be seen from the above data, the supported catalyst provided by the present invention has a significant effect on removing linear polysiloxane, and the content of the short-chain bodies in examples 1 to 3 can be as low as 6 to 10 × 10^-5Percent; examples 4 to 7 can also achieve 1 to 2X 10^-3% of; the cleaning rate of the comparative example short wire body is about 0.1 percent, and the method is not suitable for being applied to a plurality of fields with strict requirements on the content of the short wire body, such as products of aerospace, electronic and electric appliances and the like.

The above data fully illustrate the advantages of the supported catalysts for purifying cyclosiloxanes provided by the present invention.