CN115612030A - A kind of castor oil-based flame retardant plasticizer and preparation method thereof - Google Patents

Abstract

A castor oil-based flame-retardant plasticizer and a preparation method thereof, wherein ricinoleoyl ethyl methacrylate and pentaerythritol tetra-3-mercaptopropionate are mixed in a solvent, azobisisobutyronitrile is used as a catalyst, and the reaction ends After purification, the castor oil-based intermediate is obtained; the castor oil-based intermediate and the flame retardant containing terminal double bonds are mixed in a solvent, and azobisisobutyronitrile is used as a catalyst. After the reaction is completed, castor oil is obtained after purification Based flame retardant plasticizer. The present invention prepares a castor oil-based plasticizer with excellent flame-retardant properties through a click reaction, and the development of a new bio-based flame-retardant plasticizer can not only effectively solve the current problems of huge consumption of petroleum-based resources and environmental pollution, but also has a positive impact on sustainable development. Significance. The bio-based plasticizer has good flame retardancy and has broad application prospects in many industrial fields.

Description

A kind of castor oil-based flame retardant plasticizer and preparation method thereof

technical field

The invention belongs to the technical field of chemical synthesis, and in particular relates to a castor oil-based plasticizer with excellent flame retardancy and a preparation method thereof.

Background technique

With the rapid economic development and the continuous improvement of environmental protection requirements, replacing petroleum resources with renewable resources has become the main trend of current economic development. Vegetable oil has been widely used in coatings, foams, flame retardants, plasticizers, etc. due to its advantages of renewability, low cost, less environmental pollution, and biodegradability. Among them, plasticizer is an important additive added to plastics, resins or elastomers to change their processability, plasticity, flexibility and tensile properties. In recent years, reports on bio-based plasticizer products have emerged one after another. Using renewable resources as the main raw material to prepare bio-based plasticizers not only reduces the consumption of petrochemical products in the plastics industry, but also reduces the impact of petrochemical raw materials in the production process. Environmental pollution has the dual effects of saving oil resources and protecting the environment, so it has important application value and broad development space.

Castor oil is one of the four major inedible oils in the world. It is mainly produced in China, Brazil and India. It is a renewable vegetable oil with low price and wide sources, and is widely used in industrial fields. Castor oil is a light yellow viscous non-drying oil, the main component is fatty acid glycerides, and the molecular structure contains three types of active reactive groups such as hydroxyl, ester and double bonds, which can undergo esterification, hydrolysis, double bond Chemical reactions such as addition and epoxidation ring opening. According to the structural characteristics of its molecules, its chemical structure can be modified by using the principles of addition, polycondensation, and esterification to obtain castor oil-based products with different properties.

Although bio-based plasticizers have significant advantages in saving resources and protecting the environment, some specific properties (flame retardancy, etc.) still need to be further improved. This method aims at improving the flame retardant properties of bio-based plasticizers, and attempts to adjust and design the structure of plasticizers from the molecular level to synthesize castor oil-based flame retardant plasticizers. On the one hand, it can significantly improve the flame retardant efficiency compared with additive flame retardants. On the other hand, the introduction of flame-retardant molecules into the structure of castor oil-based plasticizers by using the click reaction of thiols with double bonds has little effect on the mechanical properties of polyvinyl chloride (PVC) resins. The castor oil-based flame retardant plasticizer is not only environmentally friendly, but also has high thermal stability, good flame retardancy, non-toxicity, and prevents dripping, etc. At the same time, the introduced sulfur endows the material with the function of preventing thermal degradation and thermal oxidative degradation. The positively charged α-C atom acts as an electrophilic center to react with PVC, which can effectively inhibit the blackening of PVC. In summary, under the joint influence of various factors, the flame retardancy and thermal stability of castor oil-based plasticizers are significantly improved. The method is not only beneficial to the industrial promotion of castor oil, and its development towards multiple types and high performance, but also helps to expand the application range of castor oil-based products.

Contents of the invention

Technical problem to be solved: the present invention provides a castor oil-based flame retardant plasticizer and its preparation method. As a new type of biomass plasticizer, the material improves its flame retardant performance on the basis of saving resources and protecting the environment And thermal stability, which is of great significance for the high-value utilization of castor oil products, bio-based additives and other industrial development.

Technical solution: a method for preparing a castor oil-based flame-retardant plasticizer, comprising the following steps: (1) mixing ricinoleoyl ethyl methacrylate and pentaerythritol tetra-3-mercaptopropionate in a solvent, and the reaction temperature 25-60°C, nitrogen protection, wherein the molar ratio of ricinoleyl methacrylate to pentaerythritol tetra-3-mercaptopropionate is 1:(1-3), azobisisobutyronitrile is the catalyst, the catalyst The content is 0.1%-2% of the mass of ricinoleyl ethyl methacrylate, and the reaction time is 0.5-24h; after the reaction is completed, the castor oil-based intermediate is obtained after purification; (2) the castor oil-based intermediate is mixed with Double bond flame retardant, mixed in a solvent, the reaction temperature is 25-60 ° C, nitrogen protection, wherein the molar ratio of castor oil-based intermediates and flame retardants containing terminal double bonds is 1:(1-5 ), azobisisobutyronitrile is the catalyst, the catalyst content is 0.1%-2% of the mass of ricinoleoyl ethyl methacrylate, and the reaction time is 0.5-24h; after the reaction is completed, castor oil-based flame-retardant plasticizer is obtained after purification agent.

The solvent described in step (1) and step (2) is any one in tetrahydrofuran, dichloromethane, chloroform, acetone.

The reaction time of the castor oil-based intermediate described in step (1) is 12 hours, and the reaction temperature is 45° C.

The amount of azobisisobutyronitrile described in step (1) is 1.5wt.% of the total mass of the reaction system.

The flame retardant containing terminal double bonds described in step (2) is dibromostyrene, pentabromobenzyl acrylate, bis (beta-chloroethyl) vinyl phosphonate, methacrylate-2-hydroxyethyl Either of the diphenyl phosphate esters.

The molar ratio of the castor oil-based intermediate described in step (2) and the flame retardant containing terminal double bonds is 1:3.

The amount of azobisisobutyronitrile used in step (2) is 2wt.% of the total mass of the reaction system.

The reaction time described in step (2) is 30min-12h.

The castor oil-based flame-retardant plasticizer prepared by the preparation method.

Beneficial effects: the present invention uses castor oil-based plasticizer prepared from ricinoleyl methacrylate and pentaerythritol tetrakis(3-mercaptopropionate) and a flame retardant containing terminal double bonds as raw materials, and is prepared by click reaction Castor oil based plasticizer with excellent flame retardant properties. The development of new bio-based flame retardant plasticizers can not only effectively solve the current problems of huge consumption of petroleum-based resources and environmental pollution, but also has great significance for sustainable development. The bio-based plasticizer has good flame retardancy and has broad application prospects in many industrial fields.

Description of drawings

Fig. 1 thermogravimetric analysis curve of plasticized PVC products;

Fig. 2 Mechanical properties of plasticized PVC material;

Table 1 plasticized PVC product formula;

Table 2 Oxygen index of plasticized PVC products.

detailed description

Example 1

Mix ricinoleoyl ethyl methacrylate and pentaerythritol tetra-3-mercaptopropionate in tetrahydrofuran, the reaction temperature is 50°C, nitrogen protection, wherein ricinoleoyl ethyl methacrylate and pentaerythritol tetra-3-mercaptopropionate The molar ratio of the acid ester is 1:2, azobisisobutyronitrile is the catalyst, the catalyst content is 1% of the mass of ricinoleyl methacrylate, and the reaction time is 12h; the castor oil-based intermediate is obtained after the reaction is completed and purified. body (1). Add castor oil-based intermediate (1) and dibromostyrene to the reaction flask, and the molar ratio of the reactants is: castor oil-based plasticizer (1):flame retardant molecule (dibromostyrene)=1:1. Add the catalyst azobisisobutyronitrile, the total amount is 2wt.% of the mass of ricinoleoyl ethyl methacrylate, under nitrogen protection, heat to 60°C and stir for 12 hours. After the reaction is completed, the castor oil-based flame-retardant plasticizer is obtained after purification. agent. The obtained castor oil-based flame-retardant plasticizer was blended with PVC to prepare PVC material, and its mechanical properties and flame-retardant properties were tested. When 20% of the castor oil-based plasticizer is added, the limiting oxygen index is 28.5±1.0%, the tensile strength is 26±0.5MPa, and the elongation at break is 218±5%.

Example 2

Mix ricinoleoyl ethyl methacrylate and pentaerythritol tetra-3-mercaptopropionate in tetrahydrofuran, the reaction temperature is 50°C, nitrogen protection, wherein ricinoleoyl ethyl methacrylate and pentaerythritol tetra-3-mercaptopropionate The molar ratio of the acid ester is 1:2, azobisisobutyronitrile is the catalyst, the catalyst content is 1% of the mass of ricinoleyl methacrylate, and the reaction time is 12h; the castor oil-based intermediate is obtained after the reaction is completed and purified. body (1). Castor oil-based intermediate (1), pentabromobenzyl acrylate are added in the reaction flask, and the reactant mol ratio is: castor oil-based plasticizer (1): flame retardant molecule (pentabromobenzyl acrylate)=1: 2. Add catalyst azobisisobutyronitrile, the total amount is 1.5wt.% of the mass of ricinoleoyl ethyl methacrylate, nitrogen protection, heat to 50 ° C and stir for 12 hours, after the reaction is completed and purified, castor oil-based flame retardant plasticizer. The obtained castor oil-based flame retardant plasticizer was blended with PVC to prepare PVC material, and its performance was tested. When 40% of the castor oil-based plasticizer is added, the limiting oxygen index is 33.8±0.8%, the tensile strength is 11±0.6MPa, and the elongation at break is 299±7%.

Example 3

Mix ricinoleoyl ethyl methacrylate and pentaerythritol tetra-3-mercaptopropionate in dichloromethane, the reaction temperature is 50°C, nitrogen protection, wherein ricinoleoyl ethyl methacrylate and pentaerythritol tetra-3-mercaptopropionate The molar ratio of mercaptopropionate is 1:2, azobisisobutyronitrile is the catalyst, the catalyst content is 1% of the mass of ricinoleyl methacrylate, and the reaction time is 12h; after the reaction is completed, castor oil is obtained after purification Based intermediate (1). Add the castor oil-based intermediate (1) and dibromostyrene into the reaction flask, and the molar ratio of the reactants is: castor oil-based plasticizer (1):flame retardant molecule (dibromostyrene)=1:3. Add the catalyst azobisisobutyronitrile, the total amount is 1wt.% of the mass of ricinoleoyl ethyl methacrylate, under nitrogen protection, heat to 45°C and stir for 15 hours. After the reaction is completed, the castor oil-based flame-retardant plasticizer is obtained after purification. agent. The obtained castor oil-based flame retardant plasticizer was blended with PVC to prepare PVC material, and its performance was tested. When 60% of the castor oil-based plasticizer is added, the limiting oxygen index is 36.7±1.1%, the tensile strength is 10.6±0.2MPa, and the elongation at break is 424±11%.

Example 4

Mix ricinoleoyl ethyl methacrylate and pentaerythritol tetra-3-mercaptopropionate in dichloromethane, the reaction temperature is 40°C, nitrogen protection, wherein ricinoleoyl ethyl methacrylate and pentaerythritol tetra-3-mercaptopropionate The molar ratio of mercaptopropionate is 1:3, azobisisobutyronitrile is the catalyst, the catalyst content is 1.5% of the mass of ricinoleyl methacrylate, and the reaction time is 20h; castor oil is obtained after the reaction is completed and purified Based intermediate (2). Castor oil-based intermediate (2), diphenyl methacrylate-2-hydroxyethyl phosphate are added in the reaction flask, and the reactant molar ratio is: castor oil-based plasticizer (2): flame retardant molecule (ethylene Bis(β-chloroethyl)phosphonate)=1:1. Add the catalyst azobisisobutyronitrile, the total amount is 2wt.% of the mass of ricinoleoyl ethyl methacrylate, under nitrogen protection, heat to 60°C and stir for 12 hours. After the reaction is completed, the castor oil-based flame-retardant plasticizer is obtained after purification. agent. The obtained castor oil-based flame retardant plasticizer was blended with PVC to prepare PVC material, and its performance was tested. When 20% of the castor oil-based plasticizer is added, its initial thermal decomposition temperature is 163.2°C, and the residual carbon rate is 11.7%.

Example 5

Mix ricinoleoyl ethyl methacrylate and pentaerythritol tetra-3-mercaptopropionate in dichloromethane, the reaction temperature is 40°C, nitrogen protection, wherein ricinoleoyl ethyl methacrylate and pentaerythritol tetra-3-mercaptopropionate The molar ratio of mercaptopropionate is 1:3, azobisisobutyronitrile is the catalyst, the catalyst content is 1.5% of the mass of ricinoleyl methacrylate, and the reaction time is 20h; castor oil is obtained after the reaction is completed and purified Based intermediate (2). Castor oil-based intermediate (2), methacrylic acid-2-hydroxyethyl diphenyl phosphate are added in the reaction flask, and the reactant molar ratio is: castor oil-based plasticizer (2): flame retardant molecule R= 1:2. Add the catalyst azobisisobutyronitrile, the total amount is 2wt.% of the mass of ricinoleoyl ethyl methacrylate, under nitrogen protection, heat to 60°C and stir for 10 hours, after the reaction is completed, the castor oil-based flame-retardant plasticizer is obtained after purification agent. The obtained castor oil-based flame retardant plasticizer was blended with PVC to prepare PVC material, and its performance was tested. When 40% of the castor oil-based plasticizer is added, the initial thermal decomposition temperature is 228° C., and the residual carbon rate is 8.9%.

Example 6

Mix ricinoleoyl ethyl methacrylate and pentaerythritol tetra-3-mercaptopropionate in tetrahydrofuran, the reaction temperature is 55°C, nitrogen protection, wherein ricinoleoyl ethyl methacrylate and pentaerythritol tetra-3-mercaptopropionate The molar ratio of the acid ester is 1:2, azobisisobutyronitrile is the catalyst, the catalyst content is 0.5% of the mass of ricinoleethyl methacrylate, and the reaction time is 10h; the castor oil-based intermediate is obtained after the reaction is completed and purified. body (3). Add the castor oil-based intermediate (3) and dibromostyrene into the beaker, and the molar ratio of reactants is: castor oil-based plasticizer (3):flame retardant molecule (dibromostyrene)=1:1. Add the catalyst azobisisobutyronitrile, the total amount is 1wt.% of the mass of ricinoleoyl ethyl methacrylate, under nitrogen protection, heat to 50°C and stir for 16 hours. After the reaction is completed, the castor oil-based flame-retardant plasticizer is obtained after purification. agent. The obtained castor oil-based flame retardant plasticizer was blended with PVC to prepare PVC material, and its performance was tested. When 60% of the castor oil-based plasticizer is added, its initial thermal decomposition temperature is 226° C., and the residual carbon rate is 12.2%.

Table 1 Plasticized PVC product formula

Table 2 Oxygen index of plasticized PVC products

The present invention is not limited to the above-mentioned embodiments, and all of the contents of the present invention can be implemented and have the above-mentioned good effects.

Claims (9)

1. The preparation method of the castor oil-based flame retardant plasticizer is characterized by comprising the following steps of: (1) Uniformly mixing ricinoyl ethyl methacrylate and pentaerythritol tetra-3-mercaptopropionate in a solvent at the reaction temperature of 25-60 ℃ under the protection of nitrogen, wherein the molar ratio of ricinoyl ethyl methacrylate to pentaerythritol tetra-3-mercaptopropionate is 1 (1-3), azobisisobutyronitrile is used as a catalyst, the content of the catalyst is 0.1-2% of the mass of ricinoyl ethyl methacrylate, and the reaction time is 0.5-24 hours; after the reaction is finished, purifying to obtain a castor oil-based intermediate; (2) Uniformly mixing the castor oil-based intermediate and a flame retardant containing terminal group double bonds in a solvent, wherein the reaction temperature is 25-60 ℃, and the nitrogen protection is performed, wherein the molar ratio of the castor oil-based intermediate to the flame retardant containing terminal group double bonds is 1 (1-5), azodiisobutyronitrile is used as a catalyst, the content of the catalyst is 0.1-2% of the mass of the ricinoyl ethyl methacrylate, and the reaction time is 0.5-24h; after the reaction is finished, the castor oil based flame retardant plasticizer is obtained after purification.

2. The method for preparing a castor oil-based flame retardant plasticizer according to claim 1, wherein the solvent used in the steps (1) and (2) is any one of tetrahydrofuran, dichloromethane, chloroform and acetone.

3. The method for preparing the castor oil-based flame retardant plasticizer according to claim 1, wherein the reaction time of the castor oil-based intermediate in the step (1) is 12 hours, and the reaction temperature is 45 ℃.

4. The method for preparing the castor oil-based flame retardant plasticizer according to claim 1, wherein the amount of the azobisisobutyronitrile used in the step (1) is 1.5wt.% based on the total mass of the reaction system.

5. The method for preparing a castor oil-based flame retardant plasticizer according to claim 1, wherein the flame retardant having terminal double bonds in the step (2) is any one of dibromostyrene, pentabromobenzyl acrylate, di (β -chloroethyl) vinylphosphonate, and 2-hydroxyethyl methacrylate diphenyl phosphate.

6. The preparation method of the castor oil-based flame retardant plasticizer according to claim 1, wherein the molar ratio of the castor oil-based intermediate in the step (2) to the flame retardant having terminal double bonds is 1.

7. The method for preparing the castor oil-based flame retardant plasticizer according to claim 1, wherein the amount of the azobisisobutyronitrile used in the step (2) is 2wt.% based on the total mass of the reaction system.

8. The method for preparing a castor oil-based flame retardant plasticizer according to claim 1, wherein the reaction time of the step (2) is 30min to 12h.

9. A castor oil-based flame retardant plasticizer produced by the production method according to any one of claims 1 to 8.

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