阅读说明：本技术 一种接枝聚合型光稳定剂及其制备方法 (Graft polymerization type light stabilizer and preparation method thereof ) 是由 祝君威 刘波 江赛 蔡红云 苏波 张超 于 2020-06-22 设计创作，主要内容包括：本发明属塑料助剂技术领域,特别涉及一种接枝聚合型光稳定剂及其制备方法,以4-氨基-2,2,6,6-四甲基哌啶和对溴苯乙烯为原料,在缚酸剂的作用下,先合成中间体2,2,6,6-四甲基-N-(4-乙烯基苯基)哌啶-4-胺,中间体再经催化剂、高温高压等条件下进行聚合反应,反应结束后,降温水洗,再加活性炭脱水脱色,过滤,滤液蒸馏即可制得本发明的接枝聚合型光稳定剂；该接枝聚合型光稳定剂是一种可以抑制或减缓由于光氧化作用而使高分子材料发生降解的助剂,热稳定性优异、挥发性低、和高分子材料有较好的兼容性；本发明的合成工艺简单、制备成本低且收率高。(The invention belongs to the technical field of plastic additives, and particularly relates to a graft polymerization type light stabilizer and a preparation method thereof, wherein 4-amino-2, 2,6, 6-tetramethylpiperidine and p-bromostyrene are used as raw materials, under the action of an acid binding agent, an intermediate 2,2,6, 6-tetramethyl-N- (4-vinylphenyl) piperidine-4-amine is synthesized firstly, the intermediate is subjected to polymerization reaction under the conditions of a catalyst, high temperature and high pressure and the like, after the reaction is finished, cooling and washing are carried out, activated carbon is added for dehydration and decoloration, filtering is carried out, and filtrate is distilled to obtain the graft polymerization type light stabilizer; the graft polymerization type light stabilizer is an auxiliary agent which can inhibit or slow down the degradation of a high polymer material due to photo-oxidation, has excellent thermal stability and low volatility, and has better compatibility with the high polymer material; the synthesis process is simple, the preparation cost is low and the yield is high.)

1. A graft polymerization type light stabilizer is characterized in that the structural formula is as follows:

wherein n is 8-10.

2. The preparation method of the graft polymerization type light stabilizer according to claim 1, wherein the synthesis process route of the preparation method is as follows:

wherein n is 8-10.

3. The method for producing a graft polymerization type light stabilizer according to claim 2, characterized by comprising the steps of:

step 1, adding an intermediate 2,2,6, 6-tetramethyl-N- (4-vinyl phenyl) piperidine-4-amine, a polymerization catalyst and an auxiliary catalyst into a polymerization reaction kettle, then adding a proper amount of an organic solvent, and starting stirring;

and 2, replacing air with nitrogen, introducing nitrogen to increase the pressure in the reaction kettle, starting a heating system, raising the temperature to perform polymerization reaction, cooling and washing after a period of reaction, adding activated carbon into an organic layer after water separation for dehydration and decoloration, filtering to remove the activated carbon, and distilling the filtrate to obtain the graft polymerization type light stabilizer.

4. The method for preparing the graft polymerization type light stabilizer according to claim 3, wherein the intermediate 2,2,6, 6-tetramethyl-N- (4-vinylphenyl) piperidine-4-amine, the solvent, the catalyst and the auxiliary catalyst, and the activated carbon are fed in the mass ratio of: 1: 3-6: 0.005-0.015: 0.001-0.005: 0.008-0.012.

5. The method for preparing a graft polymerization type light stabilizer according to claim 3, wherein the organic solvent used in the steps 1 and 2 is any one of xylene, toluene, DMF, and tetrahydrofuran.

6. The method for preparing a graft polymerization type light stabilizer according to claim 3, wherein the polymerization catalyst in step 1 is any one of titanocene dichloride, zirconocene dichloride and titanium chloride/aluminum alkyl, and the auxiliary catalyst is any one of MAO, EAO and modified MMAO.

7. The method for preparing a graft polymerization type light stabilizer as claimed in claim 3, wherein the polymerization temperature in step 2 is 120-180 ℃, the polymerization pressure is 1.0-4.0MPa, and the reaction time is 4-10 hours.

8. The process for producing a graft polymerization type light stabilizer according to claim 3, wherein the intermediate 2,2,6, 6-tetramethyl-N- (4-vinylphenyl) piperidin-4-amine of step 1 is produced by:

Adding p-bromostyrene into a reaction kettle, adding a proper amount of organic solvent and polymerization inhibitor, starting stirring to uniformly mix the p-bromostyrene and the polymerization inhibitor, controlling the temperature to be 50-80 ℃, dropwise adding 4-amino-2, 2,6, 6-tetramethylpiperidine, controlling the temperature to be 50-80 ℃, starting dropwise adding alkali liquor, keeping the temperature to be 80-110 ℃ after dropwise adding, reacting for 3-8 hours, washing with water after the reaction is finished, taking an organic layer after water is separated, and evaporating the solvent to dryness to obtain an intermediate 2,2,6, 6-tetramethyl-N- (4-vinylphenyl) piperidine-4-amine.

9. The method for preparing a graft polymerization type light stabilizer according to claim 3, wherein the materials of p-bromostyrene, 4-amino-2, 2,6, 6-tetramethylpiperidine, organic solvent, polymerization inhibitor and alkali are calculated according to the mass ratio: 1: 0.868-1.02: 2-5: 0.005-0.01: 0.22-0.44.

Technical Field

The invention belongs to the technical field of plastic additives, and particularly relates to a graft polymerization type light stabilizer and a preparation method thereof.

Background

The light stabilizer is an additive of high molecular products, which can shield or absorb the energy of ultraviolet rays, quench singlet oxygen and decompose hydroperoxide into inactive substances, etc., so that the possibility of photochemical reaction can be eliminated or slowed down, and the process of photoaging can be prevented or delayed under the radiation of light, thereby achieving the purpose of prolonging the service life of the high molecular products.

The hindered amine is an organic amine compound with steric hindrance, has a good inhibition effect on the photo-oxidative degradation reaction of high polymers and organic compounds, and is a light stabilizer with excellent performance. However, the molecular weight of the existing hindered amine light stabilizer is generally small, the compatibility with high molecular materials is not good, and the existing hindered amine light stabilizer is not resistant to extraction, so that the research on the high molecular weight hindered amine light stabilizer is the leading trend of the market of the existing light stabilizer.

The high molecular weight polymeric light stabilizer has the characteristics of excellent processing thermal stability, very low volatility, migration resistance, extraction resistance, gas fading resistance and the like. The light stabilizer has good resin intermiscibility and good water extraction resistance, and has excellent long-acting light aging resistance compared with a common low-molecular-weight hindered amine light stabilizer. The product is widely used for products such as polypropylene (pp), polyethylene (pe), polystyrene (ps), abs resin, polyurethane (pu), polyester elastomer and the like. Has good synergistic effect with the antioxidant and the ultraviolet absorbent, and can further improve the heat resistance and the light aging resistance of the product.

Disclosure of Invention

The invention solves the technical problems in the prior art and provides a graft polymerization type light stabilizer and a preparation method thereof.

In order to solve the problems, the technical scheme of the invention is as follows:

a graft polymerization type light stabilizer has the following structural formula:

wherein n is 8-10.

The synthesis process route of the graft polymerization type light stabilizer is as follows:

wherein n is 8-10.

Preferably, the preparation method of the graft polymerization type light stabilizer comprises the following steps:

step 1, adding a certain mass of an intermediate 2,2,6, 6-tetramethyl-N- (4-vinyl phenyl) piperidine-4-amine, a polymerization catalyst and an auxiliary catalyst into a polymerization reaction kettle, then adding a proper amount of an organic solvent, and starting stirring;

and 2, replacing air with nitrogen, introducing nitrogen to increase the pressure in the reaction kettle, starting a heating system, raising the temperature to perform polymerization reaction, cooling and washing after a period of reaction, adding activated carbon into an organic layer after water separation for dehydration and decoloration, filtering to remove the activated carbon, and distilling the filtrate to obtain the graft polymerization type light stabilizer.

Preferably, the intermediate 2,2,6, 6-tetramethyl-N- (4-vinylphenyl) piperidine-4-amine, the solvent, the catalyst and the auxiliary catalyst, and the activated carbon are fed according to the mass ratio: 1: 3-6: 0.005-0.015: 0.001-0.005: 0.008-0.012.

Preferably, the organic solvent in step 1 and 2 is any one of xylene, toluene, DMF and tetrahydrofuran.

Preferably, the polymerization catalyst in step 1 is any one of titanocene dichloride, zirconocene dichloride and titanium chloride/aluminum alkyl, and any one of auxiliary catalysts MAO, EAO and modified MMAO.

Preferably, the polymerization temperature in the step 2 is 120-180 ℃, the polymerization pressure is 1.0-4.0MPa, and the reaction time is 4-10 hours.

Preferably, the preparation method of the intermediate 2,2,6, 6-tetramethyl-N- (4-vinyl phenyl) piperidine-4-amine in the step 1 comprises the following steps:

adding a certain amount of p-bromostyrene into a reaction kettle, adding a proper amount of organic solvent and polymerization inhibitor, starting stirring to mix uniformly, controlling the temperature to be 50-80 ℃, dropwise adding 4-amino-2, 2,6, 6-tetramethylpiperidine, controlling the temperature to be 50-80 ℃, starting dropwise adding alkali liquor, keeping the temperature to be 80-110 ℃ after dropwise adding, reacting for 3-8 hours at the temperature of 80-110 ℃, washing with water after the reaction is finished, taking an organic layer after water is separated, and evaporating the solvent to dryness to obtain an intermediate 2,2,6, 6-tetramethyl-N- (4-vinylphenyl) piperidine-4-amine;

preferably, the p-bromostyrene, the 4-amino-2, 2,6, 6-tetramethylpiperidine, the organic solvent, the polymerization inhibitor and the alkali are fed according to the mass ratio: 1: 0.868-1.02: 2-5: 0.005-0.01: 0.22-0.44.

Compared with the prior art, the invention has the advantages that,

The graft polymerization type light stabilizer obtained by the invention is an auxiliary agent which can inhibit or slow down the degradation of the high polymer material due to the photooxidation, and compared with the prior HALS product, the graft polymerization type light stabilizer has more excellent ultraviolet and thermal stability, low volatility and better compatibility with the high polymer material; has good compatibility with most industrial solvents and excellent polymer compatibility, and is suitable for polypropylene, polyethylene plastics, fiber products and the like.

The graft polymerization type light stabilizer has the advantages of simple synthesis process, low preparation cost and high yield, and is an ideal process for realizing industrial production.

The specific implementation mode is as follows:

in order to enhance the understanding of the present invention, the following detailed description of the present invention is given with reference to the examples.