CN108503732B - Dehydroabietyl amide internal plasticization PVC material and preparation method thereof - Google Patents
Dehydroabietyl amide internal plasticization PVC material and preparation method thereof Download PDFInfo
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Abstract
The dehydroabietylamide internal plasticization PVC material is prepared by directly carrying out substitution reaction on dehydroabietylamide and PVC, precipitating by using methanol/distilled water solution, washing and finally drying. The method can reduce the glass transition temperature of the PVC product to 43 ℃, increase the elongation at break to 400 percent, and has no plasticizer migration in distilled water, acid solution, alkali solution, vegetable oil ester and organic solvent. The dehydroabietylamide internal plasticization PVC material has practical value in the field of PVC products with higher requirements on migration resistance and volatilization resistance.
Description
Technical Field
The invention belongs to the field of organic synthesis, and particularly relates to a dehydroabietylamide internal plasticization PVC material and a preparation method thereof, and particularly relates to a method for synthesizing a dehydroabietylamide internal plasticizer by dehydroabietylacid glycidyl ester and a series of polyamines, and then directly carrying out substitution reaction with PVC to prepare an internal plasticization PVC material.
Background
Polyvinyl chloride is one of five common synthetic resins in synthetic materials, and the yield is second only to that of polyethylene. Polyvinyl chloride has good physical properties and mechanical properties, and is widely applied to packaging materials, building materials, daily-use consumer goods, electronic materials and the like. Pure PVC is difficult to process due to the special chain molecular structure of polyvinyl chloride, which usually requires the addition of large amounts of plasticizer. The capacity of the plasticizer in China reaches more than 450 million tons, and 80 percent of the plasticizer is the phthalate plasticizer. The phthalate plasticizer has low price compared with other plasticizers, and excellent plasticizing performance, so the phthalate plasticizer is widely applied in the global range. The o-benzene plasticizer is easy to be extracted by solvent, can enter human body through various ways such as oral, respiratory tract and intravenous infusion, and has toxic effect on a plurality of systems of the organism. Therefore, the use in medical instruments, food packaging materials and children's toys is prohibited in succession in europe, the united states, japan and korea. The raw materials for the synthesis of ortho-benzene plasticizers are all derived from petrochemical resources and this industrial model is not sustainable. The use of biomass resources to synthesize plasticizer products has received much attention from researchers, with vegetable oil-based plasticizers being the most common. The vegetable oil-based plasticizer mainly comprises epoxy and polyester. Although the plasticizing efficiency of the vegetable oil-based monomer plasticizer is high, the plasticizer is easy to extract a solvent; the vegetable oil-based polyester plasticizer has high viscosity, poor low-temperature performance and strong polyester macromolecule polarity, so that the plasticizing efficiency is low, and the vegetable oil-based polyester plasticizer and the polyester macromolecule have limitations on the substitution of the traditional o-benzene plasticizer.
The internal plasticizer is a part of polymer molecules, and the introduction of the internal plasticizer can effectively reduce the regularity of polymer molecular chains, increase the distance between the molecular chains, weaken the acting force between the molecular chains, further increase the lubricity of the molecular chains, plasticize a polymer product and obviously improve the durability of the polymer product. Rosin and its derivative products have special three-membered ring phenanthrene frame structure, the structure part is similar to the benzene ring structure of ortho-benzene plasticizers, and scholars use rosin to synthesize plasticizers with good heat resistance and electrical insulation performance, such as trioctyl maleopimaric acid, long-chain rosin ester, and the like. The internal plasticizer and the internal plasticized PVC material are synthesized by utilizing biomass resources, so that the sustainable utilization of resource environment can be realized, the synthesized internal plasticized PVC material has no plasticizer migration, the property of the product can be stabilized for a long time, and the potential threat to human bodies caused by the migration of the plasticizer is reduced.
Disclosure of Invention
The technical problem to be solved is as follows: the invention provides a dehydroabietylamide internal plasticization PVC material and a preparation method thereof. The series dehydroabietylamide and PVC are directly substituted to obtain the internal plasticization PVC material. The preparation method is simple, and the durability of the plasticized PVC product can be effectively improved.
The technical scheme is as follows: the dehydroabietylamide internal plasticization PVC material has the following chemical structure general formula:
wherein m is 100-; r is-NH-or- (CH)2-NH-CH2)n’-，n’＝1-10。
The preparation method of the dehydroabietylamide internal plasticization PVC material is characterized in that dehydroabietylamide and PVC are subjected to direct substitution reaction, then are precipitated by methanol/distilled water solution, and are washed and finally dried to obtain the dehydroabietylamide internal plasticization PVC material; the reaction temperature is 40-160 ℃, the reaction time is 0.1-12 h, the solvent required by the reaction is nitrogen-nitrogen dimethyl amide, tetrahydrofuran, acetone, dichloromethane or cyclohexanone, and the mass ratio of the dehydroabietic acid amide to the PVC is (0.1-4) to 1.
The dehydroabietylamide is prepared by reacting dehydroabietylate glycidyl ester with series polyamine, wherein the reaction temperature is 60-200 ℃, the reaction time is 1-24 h, and the molar ratio of the dehydroabietylate glycidyl ester to the series polyamine is 1 (1-6).
The series of polyamine is at least one of diethylenetriamine, triethylene tetramine, tetraethylene pentamine and pentaethylene hexamine.
The dehydroabietic acid glycidyl ester is synthesized by dehydroabietic acid and epoxy chloropropane.
The mole ratio of the dehydrolongitudinal acid to the epichlorohydrin is 1 (3-9).
The synthesis of dehydroabietic acid and epichlorohydrin is carried out by two-stage heating synthesis reaction, wherein the reaction synthesis temperature of the first stage is 117 ℃, and the reaction time is 2 hours; the reaction temperature in the second stage was 60 ℃ and the reaction time was 3 hours.
The catalyst in the first stage is benzyltriethylammonium chloride, and the dosage of the benzyltriethylammonium chloride is 0.1-1% of the total mass of reactants.
Calcium oxide and sodium hydroxide are added in the second stage, and the dosage of the calcium oxide and the sodium hydroxide is respectively 2.5 to 7.5 percent of the total mass of reactants
Has the advantages that: aiming at the problem of poor solvent extraction resistance and volatility resistance of the phthalate plasticizer, the dehydroabietylamide internal plasticizer is synthesized by dehydrolongitudinal acid and series of polyamines, and is directly subjected to substitution reaction with PVC to obtain the internally plasticized PVC material. The invention not only produces plasticized PVC products, but also has no plasticizer migration. The raw material of the invention is forest product rosin, the price of the raw material is low and the raw material is easy to obtain, and the high-value utilization of the forest product rosin which is a characteristic resource can be realized. A series of internal plasticization PVC materials prepared by the invention can provide theoretical support for the perfection of an internal plasticization mechanism by researching the influence of the branched chain on the performance of the plasticized PVC material. Meanwhile, the invention can reduce the glass transition temperature of the PVC product to 43 ℃, increase the elongation at break to 400 percent, and has no plasticizer migration in distilled water, acid solution, alkali solution, vegetable oil ester and organic solvent. The dehydroabietylamide internal plasticization PVC material has practical value in the field of PVC products with higher requirements on migration resistance and volatilization resistance.
Drawings
FIG. 1 is an infrared spectrum of PVC;
FIG. 2 is a chart of the infrared spectrum of the plasticized PVC material of example 1;
FIG. 3 is a Differential Scanning Calorimetry (DSC) curve of PVC;
FIG. 4 is a DSC curve of the internally plasticized PVC material prepared in example 1.
Detailed Description
Example 1
Synthesis of dehydro-glycidyl gallate
50g of dehydroabietic acid, 150g of epichlorohydrin, 0.381g of benzyltriethylammonium chloride, reacting at 117 ℃ for 2h, cooling to 60 ℃, and adding 6.62g of sodium hydroxide and 9.272g of calcium oxide. The reaction was continued for 3 hours, after which it was filtered using celite and filter paper, and then the product was obtained by vacuum distillation of excess epichlorohydrin at 100 ℃.
Synthesis of dehydroabietylamide
18g of dehydroabietic acid glycidyl ester, 10g of diethylenetriamine and stirring for reaction at 130 ℃ for 8 hours under the protection of nitrogen. Then cooling to room temperature, washing with distilled water at 50 ℃ for 3-5 times, and then carrying out vacuum distillation to obtain the product.
Preparation of dehydroabietylamide internal plasticization PVC material
5g of PVC and 2g of dehydroabietylamide are dissolved in 80mL of nitrogen-nitrogen dimethyl amide, the temperature is controlled at 80 ℃, stirring is carried out for reaction for 2h, the temperature is reduced to room temperature, 10 wt.% methanol aqueous solution is used for precipitating polymer, and the internal plasticization PVC material is obtained after separation and drying. The IR spectra of the PVC and internally plasticized PVC are shown in FIGS. 1 and 2, respectively. Fig. 3 and 4 are DSC curves for PVC and the internally plasticized PVC material prepared in this example, respectively. Table 1 shows that the glass transition temperature of PVC is 85 ℃ and that of the internally plasticized PVC material is 43 ℃. The internal plasticization PVC material film is prepared by using a solvent casting method and taking tetrahydrofuran as a solvent. The same procedure was used to prepare dioctyl phthalate/PVC films (mass ratio 6: 10). Respectively immersing product films with certain mass into n-hexane solvent, keeping the temperature at 50 ℃ for two hours, drying and weighing, and calculating the mass loss percentage of the plasticizer to evaluate the solvent extraction resistance of the internal plasticization PVC material, wherein the results are shown in Table 1.
Example 2
Synthesis of dehydro-glycidyl gallate
50g of dehydroabietic acid, 160g of epichlorohydrin, 0.381g of benzyltriethylammonium chloride, reacting at 117 ℃ for 2h, cooling to 60 ℃, and adding 6.62g of sodium hydroxide and 9.272g of calcium oxide. The reaction was continued for 3 hours, after which it was filtered using celite and filter paper, and then the product was obtained by vacuum distillation of excess epichlorohydrin at 100 ℃.
Synthesis of dehydroabietylamide
18g of dehydroabietic acid glycidyl ester and 15g of triethylene tetramine, and stirring and reacting for 8 hours at 130 ℃ under the protection of nitrogen. Then cooling to room temperature, washing with distilled water at 50 ℃ for 3-5 times, and then carrying out vacuum distillation to obtain the product.
Preparation of dehydroabietylamide internal plasticization PVC material
5g of PVC and 2g of dehydroabietylamide are dissolved in 80mL of nitrogen-nitrogen dimethyl amide, the temperature is controlled at 80 ℃, stirring is carried out for reaction for 2h, the temperature is reduced to room temperature, 10 wt.% methanol aqueous solution is used for precipitating polymer, and the internal plasticization PVC material is obtained after separation and drying. The internal plasticization PVC material film is prepared by using a solvent casting method and taking tetrahydrofuran as a solvent. The same procedure was used to prepare dioctyl phthalate/PVC films (mass ratio 6: 10). Respectively immersing product films with certain mass into n-hexane solvent, keeping the temperature at 50 ℃ for two hours, drying and weighing, and calculating the mass loss percentage of the plasticizer to evaluate the solvent extraction resistance of the internal plasticization PVC material, wherein the results are shown in Table 1.
Example 3
Synthesis of dehydro-glycidyl gallate
50g of dehydroabietic acid, 170g of epichlorohydrin, 0.381g of benzyltriethylammonium chloride, cooling to 60 ℃ after reacting for 2h at 117 ℃, and adding 6.62g of sodium hydroxide and 9.272g of calcium oxide. The reaction was continued for 3 hours, after which it was filtered using celite and filter paper, and then the product was obtained by vacuum distillation of excess epichlorohydrin at 100 ℃.
Synthesis of dehydroabietylamide
18g of dehydroabietic acid glycidyl ester, 19g of tetraethylenepentamine and nitrogen protection, and stirring and reacting at 130 ℃ for 8 hours. Then cooling to room temperature, washing with distilled water at 50 ℃ for 3-5 times, and then carrying out vacuum distillation to obtain the product.
Preparation of dehydroabietylamide internal plasticization PVC material
5g of PVC and 2g of dehydroabietylamide are dissolved in 80mL of nitrogen-nitrogen dimethyl amide, the temperature is controlled at 80 ℃, stirring is carried out for reaction for 2h, the temperature is reduced to room temperature, 10 wt.% methanol aqueous solution is used for precipitating polymer, and the internal plasticization PVC material is obtained after separation and drying. The internal plasticization PVC material film is prepared by using a solvent casting method and taking tetrahydrofuran as a solvent. The same procedure was used to prepare dioctyl phthalate/PVC films (mass ratio 6: 10). Respectively immersing product films with certain mass into n-hexane solvent, keeping the temperature at 50 ℃ for two hours, drying and weighing, and calculating the mass loss percentage of the plasticizer to evaluate the solvent extraction resistance of the internal plasticization PVC material, wherein the results are shown in Table 1.
Example 4
Synthesis of dehydro-glycidyl gallate
50g of dehydroabietic acid, 180g of epichlorohydrin, 0.381g of benzyltriethylammonium chloride, cooling to 60 ℃ after reacting for 2h at 117 ℃, and adding 6.62g of sodium hydroxide and 9.272g of calcium oxide. The reaction was continued for 3 hours, after which it was filtered using celite and filter paper, and then the product was obtained by vacuum distillation of excess epichlorohydrin at 100 ℃.
Synthesis of dehydroabietylamide
18g of dehydroabietic acid glycidyl ester, 23g of tetraethylenepentamine and nitrogen protection, and stirring and reacting at 130 ℃ for 8 hours. Then cooling to room temperature, washing with distilled water at 50 ℃ for 3-5 times, and then carrying out vacuum distillation to obtain the product.
Preparation of dehydroabietylamide internal plasticization PVC material
5g of PVC and 2g of dehydroabietylamide are dissolved in 80mL of nitrogen-nitrogen dimethyl amide, the temperature is controlled at 80 ℃, stirring is carried out for reaction for 2h, the temperature is reduced to room temperature, 10 wt.% methanol aqueous solution is used for precipitating polymer, and the internal plasticization PVC material is obtained after separation and drying. The internal plasticization PVC material film is prepared by using a solvent casting method and taking tetrahydrofuran as a solvent. The same procedure was used to prepare dioctyl phthalate/PVC films (mass ratio 6: 10). Respectively immersing product films with certain mass into n-hexane solvent, keeping the temperature at 50 ℃ for two hours, drying and weighing, and calculating the mass loss percentage of the plasticizer to evaluate the solvent extraction resistance of the internal plasticization PVC material, wherein the results are shown in Table 1.
TABLE 1 Properties of PVC and of the internally plasticized PVC Material prepared in the examples
Claims (8)
1. The dehydroabietylamide internal plasticization PVC material is characterized in that the chemical structure general formula is as follows:
wherein m is 100-; r is-NH-CH2-or- (NH-CH)2-CH2)n’-NH-CH2-，n’＝1-3。
2. The method for preparing dehydroabietylamide internal plasticization PVC material according to claim 1, which is characterized in that dehydroabietylamide and PVC are subjected to direct substitution reaction, then are precipitated by methanol/distilled water solution, and then are washed, and finally are dried to obtain the dehydroabietylamide internal plasticization PVC material; the reaction temperature is 40-160 ℃, the reaction time is 0.1-12 h, the solvent required by the reaction is nitrogen-nitrogen dimethyl amide, tetrahydrofuran, acetone, dichloromethane or cyclohexanone, and the mass ratio of the dehydroabietic acid amide to the PVC is (0.1-4) to 1.
3. The method for preparing dehydroabietylamide internally plasticized PVC material according to claim 2, wherein the dehydroabietylamide is prepared by reacting dehydroabietylamide with series polyamine, the reaction temperature is 60-200 ℃, the reaction time is 1-24 h, and the molar ratio of dehydroabietylamide to series polyamine is 1 (1-6).
4. The process for the preparation of dehydroabietylamide internally plasticized PVC materials according to claim 3, characterized in that said dehydroabietic acid glycidyl ester is obtained by synthesis from dehydroabietic acid and epichlorohydrin.
5. The process for the preparation of dehydroabietylamide internally plasticized PVC materials according to claim 4, characterized in that the molar ratio of dehydroabietic acid to epichlorohydrin is 1 (3-9).
6. The method for preparing dehydroabietylamide internal plasticization PVC material according to claim 4, wherein the heating synthesis reaction is divided into two stages, the first stage reaction synthesis temperature is 117 ℃, and the reaction time is 2 hours; the reaction temperature in the second stage was 60 ℃ and the reaction time was 3 hours.
7. The process for the preparation of dehydroabietylamide internally plasticized PVC material according to claim 6, characterized in that the catalyst of the first stage is benzyltriethylammonium chloride in an amount of 0.1% to 1% of the total mass of the reactants.
8. The process for preparing dehydroabietylamide internal plasticization PVC material according to claim 6, wherein calcium oxide and sodium hydroxide are added in the second stage, and the dosage of calcium oxide and sodium hydroxide is 2.5% -7.5% of the total mass of reactants respectively.
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| JP2003160736A (en) * | 2001-09-12 | 2003-06-06 | Arakawa Chem Ind Co Ltd | Plasticizer for non-chlorine based resin and resin composition |
| CN102822231A (en) * | 2010-03-31 | 2012-12-12 | 富士胶片株式会社 | Polymer derived from dehydroabietic acid and uses thereof |
| CN103952082A (en) * | 2014-04-22 | 2014-07-30 | 南京林业大学 | Method for preparing abietinol |
| CN106751522A (en) * | 2016-12-23 | 2017-05-31 | 中国林业科学研究院林产化学工业研究所 | It is a kind of improve Graphene in the epoxy dispersiveness and interface compatibility method |
| CN106916078A (en) * | 2017-03-28 | 2017-07-04 | 中国林业科学研究院林产化学工业研究所 | A kind of abietyl polyamine derivative and its production and use |
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| JP2003160736A (en) * | 2001-09-12 | 2003-06-06 | Arakawa Chem Ind Co Ltd | Plasticizer for non-chlorine based resin and resin composition |
| CN102822231A (en) * | 2010-03-31 | 2012-12-12 | 富士胶片株式会社 | Polymer derived from dehydroabietic acid and uses thereof |
| CN103952082A (en) * | 2014-04-22 | 2014-07-30 | 南京林业大学 | Method for preparing abietinol |
| CN106751522A (en) * | 2016-12-23 | 2017-05-31 | 中国林业科学研究院林产化学工业研究所 | It is a kind of improve Graphene in the epoxy dispersiveness and interface compatibility method |
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