CN-121974954-A - Hydrolysis-resistant liquid phosphite ester and preparation method and application thereof

CN121974954ACN 121974954 ACN121974954 ACN 121974954ACN-121974954-A

Abstract

The invention discloses hydrolysis-resistant liquid phosphite ester, a preparation method and application thereof, wherein the hydrolysis-resistant liquid phosphite ester is prepared by taking 2, 4-trimethyl-1, 3-pentanediol and phosphorus trichloride or phosphite triester as raw materials, carrying out cyclization reaction, and then carrying out nucleophilic substitution on Cl or aryl and alkyl on a cyclization intermediate by higher saturated monohydric alcohol with more than 8 carbon atoms, wherein the molecular structure of the hydrolysis-resistant liquid phosphite ester is shown as a formula I. The liquid phosphite ester is novel liquid phosphite ester, the main body of the liquid phosphite ester is a six-membered ring structure, the basic structure of the phosphite ester is reserved to the maximum extent, the antioxidation effect of the phosphite ester is ensured, and the hydrophobic aliphatic chain structure on the phosphorus atom and the branched chain thereof prevents water molecules from approaching a P-O bond, so that the liquid phosphite ester is prevented from being attacked by water molecules, the hydrolysis resistance is improved under the condition that any additionally added amine hydrolysis inhibitor is not used and any sterically hindered group is not introduced, and the liquid phosphite ester has good practical value, economic value and market prospect.

Inventors

ZENG FANXIN
LEI SHUMIN
MIAO DONG
SUN QIUXIN

Assignees

江苏常青树新材料科技股份有限公司

Dates

Publication Date: 20260505
Application Date: 20260109
Priority Date: 20251231

Claims (10)

1. A hydrolysis-resistant liquid phosphite ester is characterized in that the molecular structure of the liquid phosphite ester is shown as a formula I: (formula I); Wherein R is alkyl, and the carbon number of the alkyl is more than or equal to C8.
2. The liquid phosphite ester according to claim 1, wherein the alkyl group has a carbon number of C8-C20 in the molecular structural formula of the liquid phosphite ester.
3. The liquid phosphite ester according to claim 2, wherein the number of atoms of the alkyl group is C12 to C14 in the molecular structural formula of the liquid phosphite ester.
4. A preparation method of hydrolysis-resistant liquid phosphite ester is characterized in that the method is used for preparing the liquid phosphite ester according to any one of claims 1-3, the preparation method takes 2, 4-trimethyl-1, 3-pentanediol and phosphorus trichloride or phosphite triester as raw materials, cyclization reaction is firstly carried out to obtain a cyclized intermediate, then higher saturated monohydric alcohol with more than 8 is used for nucleophilic substitution of Cl or phenyl or alkyl on the cyclized intermediate to obtain a target product, the molar ratio of the 2, 4-trimethyl-1, 3-pentanediol to the phosphorus trichloride or the phosphite triester is controlled to be 1:1-3, the molar ratio of the higher saturated monohydric alcohol with more than 8 to the cyclized intermediate is 1-3:1, and the preparation method comprises the following reaction paths: ; wherein R is an alkyl group having 8 or more carbon atoms, and R' is an aryl group or an alkyl group having 1 to 3 carbon atoms.
5. The process for producing a hydrolysis-resistant liquid phosphite ester according to claim 4, wherein the higher saturated monohydric alcohol having 8 or more carbon atoms includes, but is not limited to, octanol, nonanol, decanol, lauryl alcohol, C13 alcohol, C12-14 alcohol, myristyl alcohol, palmityl alcohol, stearyl alcohol and any of the isomers of the above alcohols.
6. The process for preparing a liquid phosphite ester against hydrolysis according to claim 4 or 5, wherein the reaction route is as follows when 2, 4-trimethyl-1, 3-pentanediol and phosphorus trichloride are used as raw materials: ; Wherein R is an alkyl group having 8 or more carbon atoms; the preparation method specifically comprises the following steps: a1 Dissolving 2, 4-trimethyl-1, 3-pentanediol and an acid binding agent in a solvent, controlling the stirring speed, slowly dropwise adding a phosphorus trichloride solution, and gradually reacting to generate a reaction solution containing a cyclized intermediate shown in a formula II; A2 Continuously and slowly dropwise adding a higher saturated monohydric alcohol solution with more than 8 carbon atoms under the stirring condition, and reacting to generate a reaction solution containing a target product shown in a formula I; a3 And (3) impurity removal and purification, namely filtering the reaction solution containing the target product shown in the formula I, and removing the acid binding agent and the solvent to obtain colorless liquid, namely the target product, namely the hydrolysis-resistant liquid phosphite ester.
7. The process for producing a hydrolysis-resistant liquid phosphite according to claim 6, wherein: the acid binding agent is any one of triethylamine, ethylenediamine, di-n-butylamine, hexamethylenediamine, pyridine, dimethylaminopyridine and ammonia; The molar ratio of the dosage of the acid-binding agent to the 2, 4-trimethyl-1, 3-pentanediol is 2, 4-trimethyl-1, 3-pentanediol, the acid-binding agent=1:1-4; The solvent is an inert solvent and comprises any one of benzene, toluene, methylene dichloride, dichloroethane, chloroform, tetrahydrofuran and dioxane; the cyclization reaction is carried out by controlling the stirring speed to be 50-100 rpm, controlling the concentration of the dropwise added phosphorus trichloride solution to be 0.02mol/mL, controlling the dripping speed to be 1-2 mL/min, controlling the dripping temperature to be 15-25 ℃, keeping the temperature to be 20-25 ℃ after the dripping is finished, and continuing stirring for 45-70 min to obtain a reaction solution containing a cyclization intermediate shown in a formula II; The nucleophilic substitution is carried out, wherein the stirring speed is controlled to be 20-50 rpm, the concentration of the dropwise added higher saturated monohydric alcohol solution is controlled to be 0.02mol/mL, the dropwise adding speed is controlled to be 1-2 mL/min, the dropwise adding temperature is controlled to be 20-25 ℃, the temperature is increased to reflux after the dropwise adding is finished, the reaction is continued for 2 hours, and then the reaction solution is cooled to the room temperature, so that the reaction solution containing the target product shown in the formula I is obtained.
8. The process for preparing a phosphite ester as claimed in claim 4 or 5, wherein the reaction route is as follows when 2, 4-trimethyl-1, 3-pentanediol and phosphite triester are used as raw materials: ; Wherein R is alkyl with more than 8 carbon atoms, and R' is aryl or alkyl with 1 to 3 carbon atoms; the preparation method comprises the following steps: Adding 2, 4-trimethyl-1, 3-pentanediol, phosphite triester, higher saturated monohydric alcohol with more than C8 and catalyst into a reaction kettle simultaneously according to a proportion, controlling temperature and pressure conditions in stages, performing cyclization reaction on the 2, 4-trimethyl-1, 3-pentanediol and the phosphite triester to generate a cyclized intermediate with a formula III, performing affinity substitution on phenyl or alkyl on the cyclized intermediate with more than C8 to generate a target product with a formula I, removing byproducts and removing the catalyst, wherein the obtained colorless liquid is the target product, namely hydrolysis-resistant liquid phosphite.
9. The process for producing a hydrolysis-resistant liquid phosphite according to claim 7, wherein: The phosphite triester comprises any one of trimethyl phosphite, triethyl phosphite, triisopropyl phosphite and triaryl phosphite; the catalyst includes, but is not limited to, any one or a combination of sodium hydroxide, potassium hydroxide, cesium hydroxide, sodium methoxide, sodium carbonate, potassium carbonate, cesium carbonate, sodium tert-butoxide, potassium tert-butoxide; The dosage of the catalyst is 0.3-0.8wt% of the total mass of the 2, 4-trimethyl-1, 3-pentanediol and the phosphite triester; the staged temperature and pressure control conditions are specifically as follows: B1 The first stage, wherein the pressure is controlled to be 0.03-0.05 MPa, the temperature is controlled to be increased to 40-60 ℃ at the speed of 5 ℃ per minute, the temperature is kept for 10-15 min, then the temperature is controlled to be increased to 110-120 ℃ at the speed of 1 ℃ per minute, and the temperature is kept for 30-50 min, so that cyclization reaction is carried out to generate cyclized intermediate reaction liquid shown in a formula III; B2 In the second stage, the pressure is controlled to be 0.08-0.10 MPa, the temperature is controlled to be increased to 140-150 ℃ at the speed of 1 ℃ per minute, the temperature is kept for 15-20 minutes, then the temperature is controlled to be increased to 160-165 ℃ at the speed of 1 ℃ per minute, the temperature is kept for 30-45 minutes, and nucleophilic substitution reaction is carried out to generate reaction liquid containing a target product shown in the formula I; b3 And in the third stage, the pressure is controlled at-0.07 to-0.10 MPa, the temperature is controlled to be increased to 200-210 ℃ at the speed of 5 ℃ per minute, the temperature is kept for 10-15 minutes, then the temperature is continuously increased to 240-250 ℃ at the speed of 5 ℃ per minute, the temperature is kept for 1-1.5 hours, byproducts are removed, and the catalyst is removed by filtering when the temperature is hot, so that the target product is obtained.
10. Use of a liquid phosphite resistant to hydrolysis, characterized in that: the hydrolysis-resistant liquid phosphite ester is prepared by the method of any one of claims 4-9, and the molecular structure of the hydrolysis-resistant liquid phosphite ester is shown as a formula I of any one of claims 1-3; The application is that the liquid phosphite ester is used as an antioxidant or a stabilizer or a flame retardant of industrial products including plastics, rubber, polyurethane, lubricating oil/grease, paint, adhesives, synthetic fibers and films.

Description

Hydrolysis-resistant liquid phosphite ester and preparation method and application thereof Technical Field The invention belongs to the technical field of organic compound synthesis, and particularly relates to hydrolysis-resistant liquid phosphite ester, and a preparation method and application thereof. Background Phosphites are a class of organophosphorus compounds whose structure may be represented by P (OR) 3, where R may be an alkyl, aryl, OR other organic group. The phosphorus atoms in phosphites are in the +3 valence state, which makes them somewhat reducing, so phosphites are commonly used as antioxidants in the plastics industry. Phosphites are classified into liquid and solid forms, and are generally characterized by being susceptible to hydrolysis due to their relatively weak phosphorus-oxygen bonds (P-O bonds) in their own structures, which are susceptible to attack by water molecules. In addition, the liquid phosphite ester has good fluidity and large surface area, so that the liquid phosphite ester is easier to contact with water molecules in air or materials under the use condition, and further hydrolysis reaction is caused. At present, the method for solving the problem of phosphite hydrolysis resistance mainly comprises 1) adding an anti-hydrolysis agent, generally an amine substance. The amine substances are directly introduced into the phosphite molecular structure, or organic amine is added into the system, so that acidic substances generated in the hydrolysis process can be neutralized, and autocatalytic hydrolysis is prevented. For example, U.S. patent No. 5856550a discloses an improvement in the storage stability of organic phosphites and phosphonites, suggesting that the stability of organic phosphites or phosphonites can be improved by the addition of organic amine-binding metal salts to prevent hydrolysis. 2) Increasing the steric hindrance around the phosphorus atom. By introducing a group having a large steric hindrance, such as a wholly aromatic group, around the phosphorus atom, the contact of water molecules with phosphorus-oxygen bonds can be effectively reduced, thereby reducing the hydrolysis rate. For example, tris (2, 4-di-t-butylphenyl) phosphite, also known as antioxidant 168, introduces an aromatic group-2, 4-di-t-butylphenyl with greater steric hindrance around the phosphorus atom in the molecular structure, thereby making it difficult for water molecules to access the phosphorus-oxygen bond, significantly reducing the rate of hydrolysis. However, the introduction of amines tends to result in staining of downstream products. The method is mainly characterized in that amine substances react with other components in the material under certain conditions to generate colored substances so as to influence the appearance of the product, in addition, colored oxidation products can be generated in the oxidation process of the amine substances, the compatibility of the amine substances and certain materials is poor, and colored deposition is easy to form on the surface of the material when the downstream product is prepared. The addition of an amine as an anti-hydrolysis agent phosphite is therefore only suitable for dark downstream product products. However, the phosphites into which sterically hindered groups are introduced are mostly solids, for example the abovementioned antioxidants 168 are in the form of white crystalline powder products, which makes the phosphite not satisfactory for certain applications (e.g. paints, polyurethanes, etc.), and the solid phosphites generally have a relatively large molecular weight, which leads to relatively low phosphorus contents, whereas the phosphite antioxidants have an action point in which the phosphorus atoms, i.e. the quantity and content of phosphorus, directly determine their antioxidant effect, so that the effect of the solid phosphites as antioxidants is generally not ideal and the range of applications is limited. Although, the Dedamard group (DELT CHEM) develops a liquid phosphite antioxidant-Eudragit AN6125 by introducing a steric hindrance group, the hydrolysis resistance of the liquid phosphite antioxidant is improved, and meanwhile, the product is kept in a liquid state. However, as mentioned above, the phosphorus atom is a key active center of phosphite ester to play an antioxidant role, and introducing a sterically hindered group around it can protect the P-O bond from being attacked by water molecules, but also limits the access of free radicals to the active site of the phosphorus atom, slowing down the reaction rate, and at the same time, introducing a sterically hindered group can increase the molecular weight of phosphite ester, reduce the diffusion rate of phosphite ester when in use, and further affect the antioxidant effect of phosphite ester. Therefore, how to develop a novel liquid phosphite structure, which has better hydrolytic stability, ensures good antioxidant effect and can avoid the color stain of do