PVC material containing amino acid heat stabilizer and preparation method thereof

Abstract

The invention relates to the technical field of polyvinyl chloride, and discloses a PVC material containing an amino acid heat stabilizer and a preparation method thereof, the PVC material containing the amino acid heat stabilizer comprises 100 parts by weight of polyvinyl chloride, 2-5 parts by weight of the amino acid heat stabilizer, 5-30 parts by weight of a plasticizer, and 1.5-2.4 parts by weight of a lubricant; n-carbobenzoxy-amino acid, a diacid monomer and lanthanum salt are subjected to a reaction to obtain the amino acid heat stabilizer, the amino acid heat stabilizer has better interfacial interaction and compatibility with polyvinyl chloride and is uniformly dispersed in a polyvinyl chloride matrix, the lanthanum element can better capture hydrogen chloride generated by thermal decomposition of the polyvinyl chloride, the HCl removal chain decomposition reaction of the polyvinyl chloride is inhibited, and the stability of the polyvinyl chloride is improved. The heat stability of polyvinyl chloride is improved, and the uniformly dispersed amino acid heat stabilizer has less influence on the mechanical properties of polyvinyl chloride, so that the PVC material keeps good tensile strength.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of polyvinyl chloride, in particular to a PVC material containing amino acid heat stabilizer and a preparation method thereof. BACKGROUND

[0002] Polyvinyl chloride has good mechanical strength, acid and alkali resistance, electrical insulation and other properties, and is widely used. However, the thermal stability of polyvinyl chloride is poor, and it is easy to decompose at high temperature to produce hydrogen chloride, and hydrogen chloride will further trigger chain decomposition reaction, which seriously affects the performance of polyvinyl chloride, and usually needs to add heat stabilizers, such as calcium-zinc stabilizer, lead salt stabilizer, rare earth stabilizer, etc.

[0003] Lanthanum-based stabilizer is mainly made of carboxylic acid ligand, lanthanum salt and other raw materials, and has the advantages of non-toxic, environmental protection, strong light and heat stability, and suitable for high temperature processing. Patent No. CN101717551B discloses a PVC stabilizer and a preparation method thereof. The stabilizer and PVC material prepared by using benzoic acid, oleic acid, stearic acid, amino acid, lanthanum, cerium rare earth compound and other raw materials have good thermal stability and plasticizing performance. However, the stabilizer prepared by using flexible long-chain alkyl carboxylic acid raw material will affect the mechanical strength of PVC material. SUMMARY

[0004] (I) The technical problem solved by the present application is to solve the problem of poor thermal stability of polyvinyl chloride, and at the same time, good mechanical strength is also achieved.

[0005] (II) Technical scheme: A preparation method of a PVC material containing amino acid heat stabilizer:

[0006] (1) Add N-benzyloxy carbonyl-amino acid and diacid monomer to ethanol aqueous solution, stir, then add lanthanum salt, heat to reaction temperature, drop sodium hydroxide aqueous solution, stir and react, filter the product, wash with hot ethanol, dry to obtain amino acid heat stabilizer.

[0007] (2) Mix polyvinyl chloride, amino acid heat stabilizer, plasticizer and lubricant in a mixer, then plasticize in an open mill to obtain a PVC material containing amino acid heat stabilizer.

[0008] Further, the volume fraction of the ethanol aqueous solution in (1) is 25-40%.

[0009] Further, the ratio of N-benzyloxy carbonyl-amino acid, diacid monomer and lanthanum salt in (1) is (1.8-2.6):(0.4-1.2):1 mol.

[0010] Further, the N-benzyloxy carbonyl-amino acid in (1) includes N-benzyloxy carbonyl-serine and N-benzyloxy carbonyl-threonine.

[0011] Further, the structure of the diacid monomer in (1) is COOH-(CH2) n -COOH, and n is 3-8.

[0012] Further, the lanthanum salt in (1) includes lanthanum nitrate, lanthanum nitrate hydrate, lanthanum chloride, and lanthanum chloride hydrate.

[0013] Further, the reaction temperature in (1) is 75-85 DEG C, and the reaction time is 30-60 min.

[0014] Further, the amount of the polyvinyl chloride in (2) is 100 parts by weight, the amount of the amino acid thermal stabilizer is 2-5 parts by weight, the amount of the plasticizer is 5-30 parts by weight, and the amount of the lubricant is 1.5-2.4 parts by weight.

[0015] Further, the plasticizer in (2) includes dioctyl phthalate, dibutyl phthalate, and di-2-ethylhexyl phthalate.

[0016] Further, the lubricant in (2) includes stearic acid, zinc stearate, and calcium stearate.

[0017] Further, the mixing time in the mixing machine in (2) is 20-30 min.

[0018] Further, the temperature of the open mill in (2) is 160-170 DEG C, and the time is 4-6 min.

[0019] (Three) beneficial technical effects: the lanthanum-based amino acid thermal stabilizer is obtained by using the diacid monomer and N-benzyloxycarbonyl-serine containing hydroxyl and carboxyl as a multi-dentate complexing monomer, and performing complexing reaction with a lanthanum salt, the oxygen atom of the ester carbonyl-C=O- and the imino-HN- contained in the lanthanum-based amino acid thermal stabilizer can form hydrogen bond interaction with the chlorine atom of the polyvinyl chloride, so that the amino acid thermal stabilizer has better interface interaction and compatibility with the polyvinyl chloride, the amino acid thermal stabilizer is uniformly dispersed in the polyvinyl chloride matrix, the lanthanum element can better capture the hydrogen chloride generated by the thermal decomposition of the polyvinyl chloride, inhibit the HCl chain decomposition reaction of the polyvinyl chloride, and thus the thermal stability of the polyvinyl chloride is improved.

[0020] The amino acid thermal stabilizer of the present application has good compatibility with the polyvinyl chloride, is uniformly dispersed in the polyvinyl chloride matrix, has less influence on the mechanical properties of the polyvinyl chloride, and makes the PVC material maintain good tensile strength. DETAILED DESCRIPTION

[0021] In order to make the purpose, technical scheme and advantages of the embodiments of the present application more clear, the technical scheme in the embodiments of the present application is described clearly and completely below.

[0022] Example 1:

[0023] (1) To 200 mL of 30% ethanol aqueous solution, 62 mmol of N- benzyloxycarbonyl-serine (CAS No. 2768-56-1), 28 mmol of succinic acid were added, after stirring, 30 mmol of lanthanum nitrate hexahydrate was added, heated to 80°C, and 25% sodium hydroxide aqueous solution was added dropwise to adjust the pH to 7, stirred and condensed refluxed for 40 min, after filtration, the product was washed with hot ethanol (temperature about 50°C), dried to obtain the amino acid thermal stabilizer.

[0024] (2) 1 kg of polyvinyl chloride, 20 g of amino acid thermal stabilizer, 300 g of dioctyl phthalate, 8 g of stearic acid, 13 g of zinc stearate were mixed in a mixer for 20 min, then in an open mill, plasticized at 165°C for 5 min to obtain a PVC material containing amino acid thermal stabilizer.

[0025] Example 2:

[0026] (1) To 200 mL of 25% ethanol aqueous solution, 54 mmol of N- benzyloxycarbonyl-serine, 36 mmol of adipic acid were added, after stirring, 30 mmol of lanthanum chloride hexahydrate was added, heated to 85°C, and 30% sodium hydroxide aqueous solution was added dropwise to adjust the pH to 7.5, stirred and condensed refluxed for 30 min, after filtration, the product was washed with hot ethanol, dried to obtain the amino acid thermal stabilizer.

[0027] (2) 1 kg of polyvinyl chloride, 30 g of amino acid thermal stabilizer, 200 g of dioctyl phthalate, 10 g of stearic acid, 14 g of calcium stearate were mixed in a mixer for 30 min, then in an open mill, plasticized at 160°C for 6 min to obtain a PVC material containing amino acid thermal stabilizer.

[0028] Example 3:

[0029] (1) To 300 mL of 40% ethanol aqueous solution, 78 mmol of N- benzyloxycarbonyl-serine, 12 mmol of glutaric acid were added, after stirring, 30 mmol of lanthanum nitrate hexahydrate was added, heated to 75°C, and 25% sodium hydroxide aqueous solution was added dropwise to adjust the pH to 7, stirred and condensed refluxed for 60 min, after filtration, the product was washed with hot ethanol, dried to obtain the amino acid thermal stabilizer.

[0030] (2) 1 kg of polyvinyl chloride, 40 g of amino acid thermal stabilizer, 50 g of dioctyl phthalate, 4 g of stearic acid, 11 g of calcium stearate were mixed in a mixer for 20 min, then in an open mill, plasticized at 170°C for 4 min to obtain a PVC material containing amino acid thermal stabilizer.

[0031] Example 4:

[0032] (1) To 300 mL of 40% ethanol aqueous solution, 70 mmol of N- benzyloxycarbonyl-threonine (CAS No. 19728-63-3), 20 mmol of adipic acid were added, after stirring, 30 mmol of lanthanum nitrate hexahydrate was added, heated to 80°C, and 25% sodium hydroxide aqueous solution was added dropwise to adjust the pH to 7.5, stirred and condensed refluxed for 30 min, after filtration, the product was washed with hot ethanol, dried, to obtain the amino acid thermal stabilizer.

[0033] (2) 1 kg of polyvinyl chloride, 50 g of amino acid thermal stabilizer, 50 g of dioctyl phthalate, 8 g of stearic acid, 12 g of zinc stearate were mixed in a mixer for 30 min, and then in an open mill, plasticized at 165°C for 5 min, to obtain the PVC material containing the amino acid thermal stabilizer.

[0034] Comparative Example 1:

[0035] (1) To 200 mL of 30% ethanol aqueous solution, 62 mmol of serine (CAS No. 302-84-1), 28 mmol of succinic acid were added, after stirring, 30 mmol of lanthanum nitrate hexahydrate was added, heated to 80°C, and 25% sodium hydroxide aqueous solution was added dropwise to adjust the pH to 7, stirred and condensed refluxed for 40 min, after filtration, the product was washed with hot ethanol, dried, to obtain the amino acid thermal stabilizer.

[0036] (2) 1 kg of polyvinyl chloride, 20 g of amino acid thermal stabilizer, 300 g of dioctyl phthalate, 8 g of stearic acid, 13 g of zinc stearate were mixed in a mixer for 20 min, and then in an open mill, plasticized at 165°C for 5 min, to obtain the PVC material.

[0037] Comparative Example 2:

[0038] (1) To 200 mL of 30% ethanol aqueous solution, 62 mmol of N- benzyloxycarbonyl-glycine (CAS No. 1138-80-3), 28 mmol of succinic acid were added, after stirring, 30 mmol of lanthanum nitrate hexahydrate was added, heated to 80°C, and 25% sodium hydroxide aqueous solution was added dropwise to adjust the pH to 7, stirred and condensed refluxed for 40 min, after filtration, the product was washed with hot ethanol, dried, to obtain the amino acid thermal stabilizer.

[0039] (2) 1 kg of polyvinyl chloride, 20 g of amino acid thermal stabilizer, 300 g of dioctyl phthalate, 8 g of stearic acid, 13 g of zinc stearate were mixed in a mixer for 20 min, and then in an open mill, plasticized at 165°C for 5 min, to obtain the PVC material.

[0040] Comparative Example 3:

[0041] (1) To 200 mL of 30% ethanol aqueous solution, 62 mmol of citric acid, 28 mmol of succinic acid were added, after stirring, 30 mmol of lanthanum nitrate hexahydrate was added, heated to 80°C, and the pH was adjusted to 7 by adding 25% sodium hydroxide aqueous solution dropwise, and the reaction was stirred and condensed at reflux for 40 min, after filtration, the product was washed with hot ethanol, dried to obtain a heat stabilizer.

[0042] (2) 1 kg of polyvinyl chloride, 20 g of heat stabilizer, 300 g of dioctyl phthalate, 8 g of stearic acid, 13 g of zinc stearate were mixed in a mixer for 20 min, then plasticized in an open mill at 165°C for 5 min to obtain a PVC material.

[0043] Comparative Example 4:

[0044] (1) To 200 mL of 30% ethanol aqueous solution, 62 mmol of myristic acid (CAS No. 544-63-8), 28 mmol of succinic acid were added, after stirring, 30 mmol of lanthanum nitrate hexahydrate was added, heated to 80°C, and the pH was adjusted to 7 by adding 25% sodium hydroxide aqueous solution dropwise, and the reaction was stirred and condensed at reflux for 40 min, after filtration, the product was washed with hot ethanol, dried to obtain a heat stabilizer.

[0045] (2) 1 kg of polyvinyl chloride, 20 g of heat stabilizer, 300 g of dioctyl phthalate, 8 g of stearic acid, 13 g of zinc stearate were mixed in a mixer for 20 min, then plasticized in an open mill at 165°C for 5 min to obtain a PVC material.

[0046] The heat stability of the PVC material was tested according to the GB / T 2917.1-2002 standard.

[0047] The tensile strength of the PVC material was tested according to the GB / T 1040.1-2018 standard.

[0048] Table 1 Properties of PVC material

[0049] Thermal stabilization time (min) Tensile strength (MPa) Example 1 28.2 35.8 Example 2 35.2 40.9 Example 3 44.9 46.4 Example 4 48.3 45.0 Comparative Example 1 26.7 34.5 Comparative Example 2 25.1 35.3 Comparative Example 3 25.6 32.8 Comparative Example 4 27.4 31.6

[0050] In Examples 1-4, diacid monomers and N-benzyloxycarbonyl-serine containing hydroxyl and carboxyl groups were used as polydentate monomers, and complexed with lanthanum salt to obtain lanthanum-based amino acid heat stabilizer. The amino acid heat stabilizer added in polyvinyl chloride contains ester group and imino group ), the oxygen atom of carbonyl-C=O- can form hydrogen bond interaction with the chlorine atom of polyvinyl chloride, so that the amino acid thermal stabilizer has better interface interaction and compatibility with polyvinyl chloride, the amino acid thermal stabilizer is uniformly dispersed in the polyvinyl chloride matrix, the lanthanide element can better capture the hydrogen chloride generated by the thermal decomposition of polyvinyl chloride, inhibit the HCl chain decomposition reaction of polyvinyl chloride, thereby improving the thermal stability of polyvinyl chloride, and the uniformly dispersed amino acid thermal stabilizer has less effect on the mechanical properties of polyvinyl chloride, so that the PVC material maintains good tensile strength.

[0051] Compared with Example 1, the serine of Comparative Example 1 does not contain an ester carbonyl group, the N-benzyloxy carbonyl-glycine of Comparative Example 2 does not contain a hydroxyl coordination group, and the citric acid of Comparative Example 3 does not contain an ester carbonyl group and an imino group, so that the compatibility of the prepared thermal stabilizer with polyvinyl chloride is lower than that of the amino acid thermal stabilizer of Example 1, resulting in a lower thermal stabilization time. Comparative Example 4 uses tetradecanoic acid as a coordination monomer, which contains a flexible alkyl long chain, which can reduce the strength of polyvinyl chloride, resulting in a lower tensile strength.

[0052] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in the description herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items.

Claims

1. A PVC material containing a heat stabilizer of an amino acid, characterized in that, The PVC material comprises 100 parts by weight of polyvinyl chloride, 2-5 parts by weight of amino acid heat stabilizer, 5-30 parts by weight of plasticizer, 1.5-2.4 parts by weight of lubricant; The preparation method of the amino acid heat stabilizer comprises: adding N-carbobenzyloxy-amino acid and diacid monomer into an ethanol aqueous solution, stirring, then adding lanthanum salt, heating to a reaction temperature, dropping sodium hydroxide aqueous solution, stirring and reacting, washing after filtering, drying to obtain the amino acid heat stabilizer.

2. The PVC material containing amino acid thermostabilizer according to claim 1, characterized in that, The plasticizer comprises dioctyl phthalate, dibutyl phthalate and di-2-ethylhexyl phthalate; the lubricant comprises stearic acid, zinc stearate and calcium stearate.

3. The amino acid heat stabilizer containing PVC material according to claim 1, characterized in that, The volume fraction of the ethanol aqueous solution is 25-40%.

4. The amino acid heat stabilizer containing PVC material according to claim 1, characterized in that, The reaction temperature is 75-85℃, and the reaction time is 30-60min.

5. The amino acid heat stabilizer containing PVC material according to claim 1, characterized in that, The ratio of N-carbobenzyloxy-amino acid, diacid monomer and lanthanum salt is (1.8-2.6):(0.4-1.2):1 mol.

6. The amino acid heat stabilizer containing PVC material according to claim 5, characterized in that, The N-carbobenzyloxy-amino acid comprises N-carbobenzyloxy-serine and N-carbobenzyloxy-threonine.

7. The amino acid heat stabilizer containing PVC material according to claim 5, characterized in that, The diacid monomer has the structural formula COOH-(CH2) n -COOH, n is 3-8.

8. The amino acid heat stabilizer containing PVC material according to claim 5, characterized in that, The lanthanum salt comprises lanthanum nitrate, lanthanum nitrate hydrate, lanthanum chloride and lanthanum chloride hydrate.

9. A process for the preparation of a PVC material containing a heat stabilizer based on an amino acid as claimed in any one of claims 1 to 8, characterized in that, The preparation method comprises: mixing polyvinyl chloride, amino acid heat stabilizer, plasticizer and lubricant in a mixing machine, then plasticizing in an open mill to obtain the PVC material containing amino acid heat stabilizer.

10. The process for the preparation of a PVC material containing amino acid thermal stabilizer according to claim 9, characterized in that, The mixing time in the mixing machine is 20-30min; the temperature of the open mill is 160-170℃, and the time is 4-6min.