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CN103030586A - Method for preparing rubber or resin multifunctional anti-aging agent - Google Patents

Method for preparing rubber or resin multifunctional anti-aging agent Download PDF

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Publication number
CN103030586A
CN103030586A CN2012104688172A CN201210468817A CN103030586A CN 103030586 A CN103030586 A CN 103030586A CN 2012104688172 A CN2012104688172 A CN 2012104688172A CN 201210468817 A CN201210468817 A CN 201210468817A CN 103030586 A CN103030586 A CN 103030586A
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reaction
aging agent
preparation
trichloromethane
silica gel
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CN2012104688172A
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周元林
范婷婷
李银涛
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Southwest Jiaotong University
Southwest University of Science and Technology
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Southwest University of Science and Technology
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Abstract

The invention discloses a method for preparing a rubber or resin multifunctional anti-aging agent. The synthesis of the anti-aging agent comprises the following two steps of: synthesizing a highly symmetrical intermediate with a dendritic structure from phenylenediamine and methyl acrylate through a Michael addition reaction; and carrying out an ester exchange reaction on the intermediate and 1,2,2,6,6-pentamethyl-piperidinol to synthesize the anti-aging agent under the condition of taking tetraisopropyl titanate as a catalyst. The anti-aging agent contains heat-resistant oxygen groups and light-stabilizing groups, and when the anti-aging agent is added into rubber or resin, the period of heat oxygen resistance and light aging resistance is delayed.

Description

The preparation method of a kind of rubber or the multi-functional anti-aging agent of resin
Technical field
The present invention relates to material synthetic preparation field, the in particular preparation method of the anti-light of a kind of rubber or resin, hot anti-aging agent.
Background technology
At present, the macromolecular material take rubber or resin as base material is widely used in every field, and demand also increases severely day by day simultaneously.Yet, affect one of difficult problem of macromolecular material application, be exactly that it can occur aging in environment.Aging refer to macromolecular material in processing, storage and use procedure, owing to being subjected to oxygen, ozone, variable color, bloom can occur, are clamminess, hardening embrittlement crackle etc. in the impact of the environmental factorss such as light, heat; The mechanical property that rubber occurs simultaneously reduces, and intensity, elongation etc. significantly descend, and ventilation property strengthens, and dielectric properties such as weaken at the phenomenon.Therefore, the research of rubber being carried out ageing-resistant performance is significant.
At present, natural rubber (NR) is the rubber item of usage quantity maximum, has excellent mechanics and processing characteristics, and low price, but it is easy to occur chemical reaction because containing a large amount of unsaturated link(age)s, so that its aging resistance is not ideal enough.In order to delay the ageing-resistant performance of unsaturated rubber, add anti-aging agent in the sizing material of being everlasting, its purpose is disruptive oxidation chain reaction, catches free radical, stops the carrying out that living chain suppresses or delaying retrogradation reacts.As far back as 1930-1940, anti-aging agent, the especially p phenylenediamine type antioxidant of amine primary structure just appearred, have good heat resistanceheat resistant oxygen and ozone resistance, be a kind of rubber anti-aging agent of excellent property.Hindered amine as light stabilizer is the new and effective photostabilizer of developing late 1970s, the organic amine compound that a class has space steric effect, because it has hydroperoxide decomposition, the quencher excited oxygen, catch free radical, and effective gene recyclable regenerative function.In recent years, along with the development of rubber item and macromolecular material, single anti-aging agent can not satisfy its demand.In order to solve the multiple anti-aging problem of rubber item, people are combined together to form a kind of multi-functional anti-aging agent with the anti-aging agent of difference in functionality by methods such as composite, chemical reactions, these multi-functional anti-aging agent can be brought into play its intermolecular synergistic effect, reach antiageing effect separately.
Summary of the invention
The present invention is intended to prepare a kind of multifunctional novel rubber Resin adhesive anti-aging agent, add it to natural rubber after, show the antiageing effect of anti-aging agent by testing its mechanical property, thermal-oxidative aging property and ultraviolet light and aging performance.After this novel anti-aging agent adds natural rubber to, can slow down the thermo-oxidative ageing of rubber and degree and the speed of photoaging, and then prolong the work-ing life of rubber.
Technical scheme of the present invention is as follows:
The preparation method of the multi-functional anti-aging agent of rubber resin may further comprise the steps:
A1: the preparation of intermediate: in there-necked flask, add Ursol D and methyl acrylate, consumption was by 1: 3.5~1: 5.5 (mol ratio), drip again Glacial acetic acid (Glacial acetic acid: methyl acrylate=5: 1 (volume ratio)), slowly being warmed up to 40~80 ℃ in the dropping process reacts, reaction process adopts tlc silica gel plate TLC (trichloromethane: methyl alcohol, v/v=10: 1-35: 1) monitoring.Behind about 10~100h, stopped reaction, rotary evaporation are removed excessive methyl acrylate and Glacial acetic acid.The gained residuum is through silica gel column chromatography (trichloromethane: acetone, v/v=10: 1-30: 1) obtain faint yellow oily thing, adopt positive isopropyl ether recrystallization namely to get intermediate.
A2: the preparation of product: under the nitrogen atmosphere, in the there-necked flask of water distilling apparatus, add intermediate and 1,2,2,6,6-pentamethyl-piperidine alcohols, consumption was by 1: 3.5~1: 5.5 (mol ratio), add again dimethylbenzene (dimethylbenzene: reactant=6: 1 (mass ratio)), reflux with most water contained in the desolventizing, adds 0.5%~1.5% (in the quality of intermediate) tetra isopropyl titanate in reaction solution, 80~125 ℃ of temperature of reaction, and constantly steam the methyl alcohol that reaction generates.Reaction process adopts tlc silica gel plate TLC (trichloromethane: methyl alcohol, v/v=10: 1~5: 1) monitor, judge the degree of carrying out of reaction according to the situation of a plate.Behind about 10~120h, stopped reaction, reaction system is collected organic phase with hot water (80 ℃) washing (50mL * 2), after anhydrous magnesium sulfate dewaters, the rotary evaporation desolventizing.The gained residuum is through silica gel column chromatography (trichloromethane: methyl alcohol, v/v=1: 1~6: 1) obtain faint yellow oily thing, adopt the isopropyl ether recrystallization namely to get pure products.
For the weak point of the antiageing effect of anti-aging agent, the present invention carries out the development of Multifucntional anti-aging agent.The concept of multi-functional anti-aging agent is exactly to introduce 2 different or a plurality of functional groups of function in a part, brings into play the effect of each group, also can produce intramolecular synergistic effect in many cases, further improves the usefulness of stablizer.This multi-functional anti-aging agent synthetic is that two small molecules that method by chemistry will have a difference in functionality are combined into a macromolecular cpd with several functions.Michael reaction and transesterification reaction are adopted in this experiment, will have the Ursol D of thermo oxidative aging performance and have 1,2,2,6 of light stability, and 6-pentamethyl-piperidine alcohols has been combined together to form the novel anti-aging agent with several functions.In preparation process, a step of most critical is exactly the control of reaction conditions, such as selection of temperature of reaction, reaction times, solvent species and catalyzer etc.Simultaneously the purification for crude product also is a difficult point of this experiment, and synthetic thick intermediate and product are purified by methods such as silica gel column chromatography (crossing pillar) and recrystallizations respectively, pass through at last infrared (FT-IR), nuclear-magnetism ( 1H-NMR) etc. characterization method is judged the structure of synthetic product.In order to study the performance of synthetic product, synthetic pure products is added in the natural rubber, by mechanical property, thermal-oxidative aging property and the ultraviolet light and aging performance of testing rubber, further determine the antiageing effect of synthetic product.The prepared Multifucntional anti-aging agent of the present invention can be applicable to multiple macromolecular material, especially in the rubber item, can play good heat resistanceheat resistant oxygen and photoaging effect.
Description of drawings
Fig. 1 is process flow sheet of the present invention;
Fig. 2 is the infrared absorption spectrum of synthetic product of the present invention;
Fig. 3 be synthetic product of the present invention proton nmr spectra ( 1H-NMR) figure;
Embodiment
Below in conjunction with specific embodiment, the present invention is described in detail.
Synthesizing of one Multifucntional anti-aging agent
1.1 the preparation of intermediate
In there-necked flask, add Ursol D and methyl acrylate, consumption was by 1: 3.5~1: 5.5 (mol ratio), drip again Glacial acetic acid (Glacial acetic acid: methyl acrylate=5: 1 (volume ratio)), slowly being warmed up to 40~80 ℃ in the dropping process reacts, reaction process adopts tlc silica gel plate TLC (trichloromethane: methyl alcohol, v/v=10: 1-35: 1) monitoring.Behind about 10~100h, stopped reaction, rotary evaporation are removed excessive methyl acrylate and Glacial acetic acid.The gained residuum is through silica gel column chromatography (trichloromethane: acetone, v/v=10: 1-30: 1) obtain faint yellow oily thing, adopt positive isopropyl ether recrystallization namely to get pure intermediate, 78 ℃ of fusing points.
1.2 product is synthetic
Under the nitrogen atmosphere, in the there-necked flask of water distilling apparatus, add intermediate and 1,2,2,6,6-pentamethyl-piperidine alcohols, consumption was by 1: 3.5~1: 5.5 (mol ratio), add again dimethylbenzene (dimethylbenzene: reactant=6: 1 (mass ratio)), reflux with most water contained in the desolventizing, adds 0.5%~1.5% (in the quality of intermediate) tetra isopropyl titanate in reaction solution, 80~125 ℃ of temperature of reaction, and constantly steam the methyl alcohol that reaction generates.Reaction process adopts tlc silica gel plate TLC (trichloromethane: methyl alcohol, v/v=10: 1~5: 1) monitor, judge the degree of carrying out of reaction according to the situation of a plate.Behind about 10~120h, stopped reaction, reaction system is collected organic phase with hot water (80 ℃) washing (50mL * 2), after anhydrous magnesium sulfate dewaters, the rotary evaporation desolventizing.The gained residuum is through silica gel column chromatography (trichloromethane: methyl alcohol, v/v=1: 1~6: 1) obtain faint yellow oily thing, adopt the isopropyl ether recrystallization namely to get pure products.
Result and discussion
Two product structures characterize
2.1 the results of IR of product
Synthetic novel anti-aging agent has been carried out infrared analysis spectrum (FT-IR) test: with KBr compressing tablet sample preparation product, at 22 ℃, relative humidity 50% is to carry out under the air condition as a setting.Test spectrogram as shown in Figure 2, and it has been carried out the peak ownership.This product of preliminary evaluation and N, N, N ' N '-[Isosorbide-5-Nitrae phenylenediamine]-propionic acid [1,2,2,6,6]-pentamethyl-] chemical formula structure of piperidines alcohol ester conforms to.
At 1725cm -1The C=O stretching vibration absorption peak on the ester group: at 1600cm -1, 1524cm -1, 1461cm -1All are C=C skeletal vibration absorption peaks on the phenyl ring, illustrated that phenyl ring exists; At 808cm -1It is the absorption peak of para-orientation on the phenyl ring; At 3000~2800cm -1Between be saturated C-H unsymmetrically and symmetrical stretching vibration absorption peak, at 1380cm -1Be-CH 3The flexural vibration absorption peak, at 1215cm -1And 1192cm -1The place is gem-dimethyl-C (CH 3) 2Two absorption peaks that the resonance coupling occur and form have illustrated that the pentamethyl-piperidyl exists; And at 3700~3200cm -1Between do not have absorption peak to occur, namely do not have alcohol-OH stretching vibration absorption peak, illustrate that transesterification reaction has occured for intermediate and pentamethyl-piperidine alcohols, has generated a kind of novel compound ester.
2.2 nuclear magnetic resonance spectroscopy
With nuclear magnetic resonance analyser product is scanned (as shown in Figure 3), can infer also that according to following analytical results synthetic product is N, N, N ' N '-[Isosorbide-5-Nitrae phenylenediamine]-propionic acid [1,2,2,6,6]-pentamethyl-] the piperidines alcohol ester.Analytical results is as follows:
δ=6.72 (s, 4H, a), δ=5.04 (tt, 4H, d), δ=3.50 (t, J=7.0Hz, 8H, b), δ=2.49 (t, J=7.0Hz, 8H, c), δ=2.23 (s, 12H, h), δ=1.82 (d, 16H, e), δ=1.46th, impurity peaks, δ=1.13 (s, 24H, f), δ=1.06 (s, 24H, g).Benzene ring hydrogens at δ=6.72 places, the hydrogen on the methylene radical that δ=3.50 places are with N links to each other, the hydrogen on the methylene radical that δ=2.49 places are with COO-carbon links to each other, pushing away it according to the n+1 rule is triplet.Hydrogen on the methyl that δ=2.23 places are with N links to each other can define 12 hydrogen according to integral area, is the hydrogen on the methylene radical at δ=1.82 places, can define 16 hydrogen according to integral area, be the hydrogen on the methyl at δ=1.13 places, and also be the hydrogen on the methyl at δ=1.06 places, because methyl herein is subject to the impact of adjacent N, so that the chemical shift of hydrogen is different on two place's methyl, can get 1,2,2 by above analysis, 6,6-pentamethyl-piperidine alcohols and intermediate reaction; The hydrogen that links to each other with COO-oxygen at δ=5.04 places, since be subject to carbonyl shielding effect impact so that the chemical shift of coupled hydrogen increase, also affected simultaneously the number at peak, the number that can determine the direct hydrogen that links to each other with COO-oxygen according to integral area is 4, intermediate and 1,2 are described, 2,6,6-pentamethyl-piperidine alcohols was by 1: 4 complete reaction.
Three, multi-functional anti-aging agent thermo-oxidative ageing and photooxidation aging property test
Synthetic multi-functional anti-aging agent is added in the natural rubber latex, prepare sample by prescription, sulfuration etc., and then test its performance.
3.1 physical and mechanical properties test
Tensile property is according to GB/T 528-2009 standard test, and sample is cut out and is dumbbell shape, tests at the UT-2080 type electronic tensile machine that High Speed Rail Testing Instruments company limited produces, and draw speed is 500mm/min.
Continue that A hardness according to GB/T 531-1999 standard testing, test at the XY-1 type durometer that chemical machinery four factories in Shanghai produce.
3.2 heatproof air aging performance test
The thermo-oxidative ageing test is tested in the GT-7017-M type thermo-oxidative ageing case that High Speed Rail Testing Instruments company limited produces according to GB/T 3512-1998 standard testing, and temperature is decided to be 100 ℃.
3.3 ultraviolet light and aging performance test
Ultraviolet light and aging is tested in the GT/QUV/SPRA Y type UV-light lamp box that High Speed Rail Testing Instruments company limited produces.
Test condition: 55 ℃ of temperature, ultraviolet wavelength are 340nm.
By Mechanics Performance Testing, thermal-oxidative aging property test and ultraviolet light and aging performance test, the result shows that synthetic Multifucntional anti-aging agent has good thermo-oxidative ageing and ultraviolet light and aging performance.
Should be understood that, for those of ordinary skills, can be improved according to the above description or conversion, and all these improvement and conversion all should belong to the protection domain of claims of the present invention.

Claims (2)

1. the preparation method of a rubber or the multi-functional anti-aging agent of resin is characterized in that, with the method for chemistry, to have 1,2,2 of the Ursol D of anti-light thermal property and ultraviolet resistance stability, 6,6-pentamethyl-piperidine alcohols combines, and forms a multi-functional anti-aging agent with high molecular.
2. preparation method according to claim 1 is characterized in that, the preparation method of described multi-functional anti-aging agent is as described below:
A: the preparation of intermediate: in there-necked flask, add Ursol D and methyl acrylate, consumption was by 1: 3.5~1: 5.5 (mol ratio), drip again Glacial acetic acid (Glacial acetic acid: methyl acrylate=5: 1 (volume ratio)), slowly being warmed up to 40~80 ℃ in the dropping process reacts, reaction process adopts tlc silica gel plate TLC (trichloromethane: methyl alcohol, v/v=10: 1-35: 1) monitoring; Behind about 10~100h, stopped reaction, rotary evaporation are removed excessive methyl acrylate and Glacial acetic acid.The gained residuum is through silica gel column chromatography (trichloromethane: acetone, v/v=10: 1-30: 1) obtain faint yellow oily thing, adopt positive isopropyl ether recrystallization namely to get intermediate;
B: the preparation of product: under the nitrogen atmosphere, in the there-necked flask of water distilling apparatus, add intermediate and 1,2,2,6,6-pentamethyl-piperidine alcohols, consumption was by 1: 3.5~1: 5.5 (mol ratio), add again dimethylbenzene (dimethylbenzene: reactant=6: 1 (mass ratio)), reflux with most water contained in the desolventizing, adds 0.5%~1.5% (in the quality of intermediate) tetra isopropyl titanate in reaction solution, 80~125 ℃ of temperature of reaction, and constantly steam the methyl alcohol that reaction generates.Reaction process adopts tlc silica gel plate TLC (trichloromethane: methyl alcohol, v/v=10: 1~5: 1) monitor, judge the degree of carrying out of reaction according to the situation of a plate; Behind about 10~120h, stopped reaction, reaction system is collected organic phase with hot water (80 ℃) washing, after anhydrous magnesium sulfate dewaters, the rotary evaporation desolventizing.The gained residuum is through silica gel column chromatography (trichloromethane: methyl alcohol, v/v=1: 1~6: 1) obtain faint yellow oily thing, adopt the isopropyl ether recrystallization namely to get pure products.
CN2012104688172A 2012-11-09 2012-11-09 Method for preparing rubber or resin multifunctional anti-aging agent Pending CN103030586A (en)

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105061808A (en) * 2015-08-29 2015-11-18 江苏麒祥高新材料有限公司 Rubber antioxidant preparing method
CN117624749A (en) * 2024-01-25 2024-03-01 江苏冠联新材料科技股份有限公司 Oil-resistant and aging-resistant rubber sealing ring and preparation method thereof

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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105061808A (en) * 2015-08-29 2015-11-18 江苏麒祥高新材料有限公司 Rubber antioxidant preparing method
CN105061808B (en) * 2015-08-29 2018-02-23 江苏麒祥高新材料有限公司 A kind of preparation method of rubber antioxidant
CN117624749A (en) * 2024-01-25 2024-03-01 江苏冠联新材料科技股份有限公司 Oil-resistant and aging-resistant rubber sealing ring and preparation method thereof
CN117624749B (en) * 2024-01-25 2024-04-05 江苏冠联新材料科技股份有限公司 Oil-resistant and aging-resistant rubber sealing ring and preparation method thereof

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Application publication date: 20130410