阅读说明：本技术 除醛剂及其制备方法与应用 (Aldehyde removing agent and preparation method and application thereof ) 是由 李少杰 朱益林 高清 赵俊飞 丁宇 于 2020-12-11 设计创作，主要内容包括：本发明涉及一种除醛剂及其制备方法与应用,主要解决现有技术中存在的常规除醛剂的甲醛去除效率低的问题,本发明通过提供一种除醛剂,其分子结构一般式为其中,R为-CH-3；R′为-O-CH-2-CHn(CH-2OH)-m；n＝3-m,m为2或3,及其制备方法与用途的技术方案,较好地解决了该问题,可用于聚氨酯泡沫制品的工业应用中。(The invention relates to an aldehyde remover, a preparation method and application thereof, and mainly solves the problem of low formaldehyde removal efficiency of the conventional aldehyde remover in the prior art Wherein R is-CH 3 (ii) a R' is-O-CH 2 ‑CHn(CH 2 OH) m (ii) a n is 3-m, m is 2 or 3, and a preparation method and a technical scheme of application thereof, better solve the problem and can be used for industrial application of polyurethane foam products.)

1. An aldehyde scavenging agent having a molecular structure of the general formula:characterized in that, wherein:

r is-CH₃；

R' is-O-CH₂-CHn(CH₂OH)_m；

Wherein n is 3-m, and m is 2 or 3.

2. The method for preparing the aldehyde removing agent according to claim 1, comprising the steps of:

a. in a reaction container, the molar ratio of (1-6): 1 adding alkyl acetoacetate and polyol to obtain a material I;

b. reacting the material I under the conditions of stirring and inert gas protection with reactants, wherein the reaction temperature is 105-150 ℃, the reaction pressure is normal pressure, the reaction time is 2-8 hours, and a low-boiling-point byproduct is separated by adopting a normal-pressure distillation method in the reaction process to obtain a material II;

c. carrying out reduced pressure distillation on the material II, wherein the pressure of the reduced pressure distillation is-0.080-0.010 Mpa, the temperature is 105-150 ℃, and removing by-products and excessive alkyl acetoacetate to obtain a material III;

d. and cooling the material III to room temperature to obtain a viscous light yellow liquid, namely the aldehyde removing agent to be prepared.

3. The method for preparing the aldehyde removing agent according to claim 2, wherein the reaction temperature is 130-150 ℃.

4. The method according to claim 2, wherein the gas inert to the reactants is at least one selected from the group consisting of nitrogen, helium and argon.

5. The method for preparing the aldehyde removing agent according to claim 1, comprising the steps of:

a. mixing an alkyl acetoacetate and a polyol in a molar ratio of 1: 2-3, adding the mixture into a reaction container, and adding a transesterification catalyst, wherein the dosage of the transesterification catalyst is 0.01-1% of the mass of the alkyl acetoacetate, so as to obtain a material I;

b. carrying out ester exchange reaction on the material I under the conditions of vacuum and stirring, wherein the reaction temperature is 90-100 ℃, the reaction pressure is-0.010-0.105 Mpa, the reaction time is 2-8 hours, and removing by-products and excessive raw materials in vacuum to obtain a material II;

c. and cooling the material II to room temperature to obtain a viscous light yellow liquid, namely the aldehyde removing agent to be prepared.

6. The method of claim 2 or 5, wherein the polyol in step a is at least one selected from 1, 3-propanediol, glycerol, and pentaerythritol.

7. The method according to claim 2 or 5, wherein said alkyl acetoacetate is at least one of ethyl acetoacetate, methyl acetoacetate and tert-butyl acetoacetate.

8. The method according to claim 5, wherein the transesterification catalyst in step a is at least one selected from the group consisting of concentrated sulfuric acid, concentrated hydrochloric acid, concentrated nitric acid, and p-toluenesulfonic acid.

9. Use of the aldehyde scavenging agent of claim 1 in polyurethane foams.

Technical Field

The invention relates to the field of aldehyde removing agents, and particularly relates to an aldehyde removing agent and a preparation method and application thereof.

Background

Formaldehyde is one of the main indoor Volatile Organic Compounds (VOCs), and is listed as the first carcinogen by the international agency for research on cancer (IARC) in 2004 as the second place on the priority control list of toxic chemicals in China, and a large amount of documents also describe that the influence of formaldehyde on human health is mainly reflected in aspects of abnormal smell, irritation, allergy, abnormal lung function, abnormal liver function, abnormal immune function and the like, and is easy to cause nasopharyngeal carcinoma, nasal cavity cancer and nasal poverty cancer of human beings, and can cause leukemia. Along with the improvement of living standard and the enhancement of environmental protection consciousness of people, the harm of formaldehyde released from materials closely related to the life of people, such as artificial boards, polyurethane foam materials, indoor decoration and the like, is more and more aroused attention of people, the research on formaldehyde removal is imperative, and an effective, simple and economic formaldehyde removal method is not only beneficial to the health of people, but also has important significance for improving the life quality and the environmental quality of people.

The formaldehyde scavenger is also called formaldehyde scavenger, formaldehyde absorptive agent or formaldehyde trapping agent, and is an aqueous solution containing compounds which can chemically react with formaldehyde under certain conditions, such as amides, phenol hydrazines, organic amines, inorganic ammonium salts and the like, and a mixture thereof, and the substances can be combined with formaldehyde in a chemical bond form to generate another stable compound, so that the release amount of the formaldehyde is reduced; therefore, many researchers are dedicated to the research on the development, synthesis and application of formaldehyde scavengers, and at present, scholars at home and abroad have made much research work on the aspect of formaldehyde scavengers, and although various formaldehyde scavengers can reduce the formaldehyde emission, the formaldehyde scavengers have many defects at the same time.

Chinese patent CN88103032.5 discloses a water-soluble active methylene used as formaldehyde scavenger, which is prepared by using substituted or unsubstituted polyhydric alcohol to perform transesterification on diethyl malonate or ethyl acetoacetate to obtain a water-soluble active methylene compound, and is applied to the removal of formaldehyde in fabrics and particle boards treated by a permanent setting finishing agent.

Disclosure of Invention

One of the technical problems to be solved by the invention is to provide an aldehyde removing agent, which has the advantage of high aldehyde removing efficiency, in order to solve the problem of low aldehyde removing efficiency of the conventional aldehyde removing agent in the prior art.

The invention also provides two preparation methods of the aldehyde removing agent corresponding to the other one of the problems.

The third technical problem to be solved by the invention is to provide an application corresponding to one of the problems, and the prepared polyurethane foam has the advantage of low aldehyde content through the application of the aldehyde removing agent.

In order to solve one of the above technical problems, the technical scheme adopted by the invention is as follows: an aldehyde scavenging agent having a molecular structure of the general formula:characterized in that, wherein:

r is-CH₃；

R' is-O-CH₂-CHn(CH₂OH)_m；

Wherein n is 3-m, and m is 2 or 3.

To solve the second technical problem, the invention adopts the following technical scheme: a preparation method of the aldehyde removing agent comprises the following steps:

a. in a reaction container, the molar ratio of (1-6): 1 adding alkyl acetoacetate and polyol to obtain a material I;

b. reacting the material I under the conditions of stirring and inert gas protection with reactants, wherein the reaction temperature is 105-150 ℃, the reaction pressure is normal pressure, the reaction time is 2-8 hours, and a low-boiling-point byproduct is separated by adopting a normal-pressure distillation method in the reaction process to obtain a material II;

c. carrying out reduced pressure distillation on the material II, wherein the pressure of the reduced pressure distillation is-0.080-0.010 Mpa, the temperature is 105-150 ℃, and removing by-products and excessive alkyl acetoacetate to obtain a material III;

d. cooling the material III to room temperature to obtain a viscous light yellow liquid which is the aldehyde removing agent to be prepared

In the technical scheme, the reaction temperature is preferably 130-150 ℃.

In the above technical solution, preferably, the gas inert to the reactant is selected from at least one of nitrogen, helium, and argon.

In the above technical solution, preferably, the polyol in step a is at least one selected from 1, 3-propanediol, glycerol, and pentaerythritol.

In the above technical solution, preferably, the alkyl acetoacetate in step a is selected from at least one of ethyl acetoacetate, methyl acetoacetate, or tert-butyl acetoacetate.

To solve the second technical problem, the invention adopts another technical scheme as follows: a preparation method of the aldehyde removing agent comprises the following steps:

a. mixing an alkyl acetoacetate and a polyol in a molar ratio of 1: 2-3, adding the mixture into a reaction container, and adding a transesterification catalyst, wherein the dosage of the transesterification catalyst is 0.01-1% of the mass of the alkyl acetoacetate, so as to obtain a material I;

b. carrying out ester exchange reaction on the material I under the conditions of vacuum and stirring, wherein the reaction temperature is 90-100 ℃, the reaction pressure is-0.010-0.105 Mpa, the reaction time is 2-8 hours, and removing by-products and excessive raw materials in vacuum to obtain a material II;

c. and cooling the material II to room temperature to obtain a viscous light yellow liquid, namely the aldehyde removing agent to be prepared.

In the above technical solution, preferably, the polyol in step a is at least one selected from 1, 3-propanediol, glycerol, and pentaerythritol.

In the above technical solution, preferably, the alkyl acetoacetate in step a is selected from at least one of ethyl acetoacetate, methyl acetoacetate, or tert-butyl acetoacetate.

In the above technical solution, preferably, the transesterification catalyst in step a is at least one selected from concentrated sulfuric acid, concentrated hydrochloric acid, concentrated nitric acid, and p-toluenesulfonic acid.

In order to solve the third technical problem, the invention adopts the technical scheme that: the prepared aldehyde removing agent is added into the formula of the polyurethane foam according to the proportion of 0.1-2.0 percent in terms of the mass percentage of the polyether polyol for foaming so as to reduce aldehydes in the polyurethane foam.

The invention provides an aldehyde removing agent, the tail end of the molecular structure of the aldehyde removing agent contains a branched chain, and the tail ends of the branched chain and the main chain both contain hydroxyl capable of reacting with formaldehyde, so that the aldehyde removing efficiency is high; the preparation method I carries out normal pressure reaction under the protection of gas which is inert to reactants, does not need vacuum, is convenient for post-treatment, can obtain the needed target product aldehyde removing agent only by vacuum distillation to remove reaction byproducts and excessive alkyl acetoacetate, does not use catalysts and organic solvents in the reaction process, has few reaction steps, is simple to operate and is environment-friendly; the second preparation method can obtain the aldehyde removing agent by reacting and removing the by-products under vacuum without other post-treatment procedures, and has the advantage of less operation steps; when the formaldehyde removing agent is added into a polyurethane foam formula according to the proportion of 0.1-2.0% of polyether polyol by mass percent to prepare polyurethane foam, the prepared polyurethane foam has low formaldehyde content, and can obtain better formaldehyde removing effect, for example, 1.0% of the formaldehyde removing agent is added in example 2, and the formaldehyde removing rate is 76%; meanwhile, the content of acetaldehyde is effectively removed, and the removal rate of the acetaldehyde is 38%; in example 6, the formaldehyde removal rate was 79% and the acetaldehyde removal rate was 47% by adding 1.5% of the aldehyde removing agent, and a good technical effect was obtained.

Detailed Description

[ example 1 ]

a. Adding 6mol of ethyl acetoacetate and 1mol of pentaerythritol into a reaction vessel to obtain a material I;

b. reacting the material I under the conditions of stirring and nitrogen protection, wherein the reaction temperature is 130 ℃, the reaction pressure is normal pressure, the reaction time is 4 hours, and a low-boiling by-product ethanol is separated by adopting a normal pressure distillation method in the reaction process to obtain a material II;

c. carrying out reduced pressure distillation on the material II, wherein the pressure of the reduced pressure distillation is-0.085 Mpa, the temperature is 130 +/-2 ℃, and removing by-products and excessive ethyl acetoacetate to obtain a material III;

d. cooling the material III to room temperature to obtain a viscous light yellow liquid, namely the aldehyde removing agent S to be prepared₁。

Removing aldehyde S from the obtained aldehyde removing agent₁The polyurethane foams obtained by foaming the polyurethane foams in the foaming formulations in the amounts shown in Table 3 have the performance index data shown in Table 4.

[ examples 2 to 3 ]

Examples 2 to 3 were carried out according to the steps in example 1, the only differences being different reaction raw materials, raw material ratios, reaction times, and reaction temperatures, as shown in table 1; the prepared aldehyde removing agent is added into a foaming formula of the polyurethane foam according to the adding amount shown in the table 3 for foaming, and the performance index data of the prepared polyurethane foam is shown in the table 4.

TABLE 1 EXAMPLES 1-3 moles of starting materials and reaction conditions used in preparation of aldehyde-removing agents

[ example 4 ]

a. Adding 1mol of ethyl acetoacetate and 2mol of pentaerythritol into a reaction vessel, and adding 98% concentrated sulfuric acid by mass concentration, wherein the using amount of the 98% concentrated sulfuric acid is 0.5% of the mass of the ethyl acetoacetate to obtain a material I;

b. carrying out ester exchange reaction on the material I under the conditions of vacuum and stirring, wherein the reaction temperature is 90 ℃, the reaction pressure is-0.090 Mpa, the reaction time is 5 hours, and removing the byproduct ethanol and excessive raw materials in vacuum to obtain a material II;

c. cooling the material II to room temperature to obtain a viscous light yellow liquid, namely the aldehyde removing agent S to be prepared₄。

Removing aldehyde S from the obtained aldehyde removing agent₄The polyurethane foams obtained by foaming the polyurethane foams in the foaming formulations in the amounts shown in Table 3 have the performance index data shown in Table 4.

[ examples 5 to 6 ]

Examples 5 to 6 were carried out according to the steps of example 4, the only differences being different reaction raw materials, raw material ratios, reaction times, and reaction temperatures, as shown in table 2; the amount of the aldehyde removing agent added in Table 3 was added to the foaming formulation of the polyurethane foam to foam, and the performance index data of the obtained polyurethane foam is shown in Table 4.

TABLE 2 moles of raw materials and reaction conditions used for the preparation of the aldehyde-removing agent in examples 4 to 6

[ COMPARATIVE EXAMPLE 1 ]

Referring to patent CN88103032.5 example 1, 1mol of ethyl acetoacetate and 1.1mol of diethylene glycol and 0.2mL of concentrated sulfuric acid with the mass concentration of 98% are added into a 1L reaction vessel under anhydrous condition, vacuum pumping is carried out, stirring and heating are started, the reaction temperature is 98 ℃, the ester exchange reaction time is 5 hours, ethanol as a byproduct is removed in vacuum during the reaction, and the water-soluble active methylene compound S is obtained after cooling to room temperature.

The obtained water-soluble active methylene compound S was added to the polyurethane foam foaming formulation in the amount shown in table 3 to foam, and the performance index data of the obtained polyurethane foam is shown in table 4.

[ example 1 ] blank

Polyurethane foams were prepared according to the formulation shown in Table 3 without the addition of an aldehyde scavenger, and the performance index data of the obtained polyurethane foams are shown in Table 4.

The raw materials described in table 3 are as follows:

1) CHE-330N: polyether polyol, wherein the hydroxyl value is 33.5-36.5 mgKOH/g, the molecular weight is 4800, the functionality is 3, and the manufacturer is Changhua chemical science and technology Limited;

2) CHK-350D: polyether polyol with a hydroxyl value of 31-35 mgKOH/g, a molecular weight of 7500, a functionality of 4, and a manufacturer of Changhua chemical science and technology, Inc.;

3) DEOA: diethanolamine, amine catalyst, basf, manufacturer;

4) ZF-10: 2- [ [2- [2- (dimethylamino) ethoxyethyl ] methylamino ] -ethanol, an amine catalyst, the manufacturer is Hensman;

5) desmodur 3133: 4, 4' -diphenylmethane-diisocyanate (MDI) and mixtures of polyisocyanates of its isomers and homologues, from a manufacturer of Korsakochun.

TABLE 3 parts by weight of polyurethane foam formulations in blank example 1, examples 1 to 6 and comparative example 1

TABLE 4 Performance index data for polyurethane foams of blank example 1, examples 1 to 6 and comparative example 1

As can be seen from the preparation processes of the embodiments 1 to 6, the aldehyde removing agent in the embodiments 1 to 3 is prepared without using a catalyst or a chemical solvent, and the reaction is carried out under normal pressure, so that the operation is simple and the environment is friendly; in the embodiments 4-6, the aldehyde removing agent can be prepared by using the catalyst, so that the whole operation steps are fewer, and the implementation is convenient; the aldehyde removing agents prepared in the embodiments 1 to 6 can obtain a good aldehyde removing effect when applied to polyurethane foam, and as can be seen from aldehyde test data in table 4, the aldehyde removing agents prepared in the embodiments 1 to 6 are respectively added to the formula of the blank embodiment 1, so that the aldehyde content in the foam, especially the content of formaldehyde and acetaldehyde, can be effectively reduced, the formaldehyde removal rate in the embodiment 1 is 53%, and the acetaldehyde removal rate is 26%; in example 2, the formaldehyde removal rate was 76% and the acetaldehyde removal rate was 38%; in example 3, the formaldehyde removal rate was 58% and the acetaldehyde removal rate was 29%; in example 4, the formaldehyde removal rate was 51% and the acetaldehyde removal rate was 24%; in example 5, the formaldehyde removal rate was 75% and the acetaldehyde removal rate was 35%; in example 6, the formaldehyde removal rate was 79% and the acetaldehyde removal rate was 47%; in comparative example 1, the formaldehyde removal rate was 40% and the acetaldehyde removal rate was 6%; it can be seen that, in the cases of the aldehyde removing agents added in the examples 1 to 6 in an amount of 0.1 to 2.0% by mass of the polyether polyol, the removal rates of formaldehyde in the polyurethane foam are all over 50% and can reach 79%, and the removal rates of acetaldehyde can reach 47%, which are higher than those in the comparative example 1, so that the aldehyde removing agent has a good aldehyde removing effect, and can be applied to the aldehyde removing application of the polyurethane foam.