阅读说明：本技术 一种用于聚氯乙烯的抗紫外剂的制备方法 (Preparation method of anti-ultraviolet agent for polyvinyl chloride ) 是由 郭吕涛 于 2020-04-29 设计创作，主要内容包括：本发明公开了一种用于聚氯乙烯的抗紫外剂的制备方法,首先以4,4’-二邻苯二甲酸酐和4-羟基哌啶盐酸盐为原料发生酯交换反应,得到了中间体W1,接着中间体W1与氢氧化钠反应成钠盐,后跟氯化镁发生复分解反应,从而制备得到了含有受阻胺和镁盐的抗紫外剂W,但是受阻胺若单独加入,会与聚氯乙烯中释放的氯化氢反应而失活,经研究,金属皂基可吸收PVC降解释放的氯化氢,因此镁盐的存在保证受阻胺的活性稳定,避免其失活,可长久的维持聚氯乙烯薄膜的抗紫外性能。(The invention discloses a preparation method of an anti-ultraviolet agent for polyvinyl chloride, which comprises the steps of firstly carrying out ester exchange reaction on 4,4' -diphthalic anhydride and 4-hydroxypiperidine hydrochloride serving as raw materials to obtain an intermediate W1, then reacting the intermediate W1 with sodium hydroxide to form sodium salt, and carrying out double decomposition reaction on magnesium chloride to obtain the anti-ultraviolet agent W containing hindered amine and magnesium salt.)

1. A preparation method of an anti-ultraviolet agent for polyvinyl chloride is characterized by comprising the following steps: the method specifically comprises the following steps:

the reaction process of the uvioresistant agent is as follows:

step one, adding 50mmol of 4,4' -diphthalic anhydride and 200ml of NMP solvent into a three-neck flask, stirring and dissolving completely, dropwise adding 105-110mmol of 4-hydroxypiperidine hydrochloride, gradually heating to perform heat preservation reaction, naturally cooling to room temperature, adding 100-150ml of 10% sodium hydroxide aqueous solution, stirring at room temperature for 25-30min, adding ethyl acetate for extraction, collecting an organic phase, performing rotary evaporation to remove the solvent, washing with anhydrous ether, and drying to obtain an intermediate W1;

and secondly, weighing 20mmol of the intermediate A, 22-25mmol of sodium hydroxide and 60-70% of ethanol water solution in mass fraction, stirring and dissolving completely, then adding 21-22mmol of magnesium chloride, stirring at room temperature for reaction, standing at room temperature for half an hour after the reaction is finished, performing suction filtration, washing with anhydrous ether, and drying to obtain the uvioresistant agent with the structure shown in the formula W.

2. The method for preparing an anti-ultraviolet agent for polyvinyl chloride according to claim 1, wherein the anti-ultraviolet agent comprises: in the first step, the temperature of the heat preservation reaction is 70-75 ℃.

3. The method for preparing an anti-ultraviolet agent for polyvinyl chloride according to claim 1, wherein the anti-ultraviolet agent comprises: in the first step, the reaction time is kept for 2-3 h.

4. The method for preparing an anti-ultraviolet agent for polyvinyl chloride according to claim 1, wherein the anti-ultraviolet agent comprises: in the second step, the reaction time is 1.5-2 h.

Technical Field

The invention belongs to the technical field of materials, and particularly relates to a preparation method of an anti-ultraviolet agent for polyvinyl chloride.

Background

The polyvinyl chloride material is widely applied due to low price and excellent performance, but the biggest defect is that the light stability is poor, the polyvinyl chloride material can absorb ultraviolet rays to generate automatic oxidation under sunlight or strong fluorescence, so that the polyvinyl chloride material is degraded, is not resistant to light oxidation and is easy to age and degrade, in order to improve the ultraviolet-proof and oxidation-resistant performance, a hindered amine ultraviolet-proof auxiliary agent is often added, but the hindered amine is easy to react with the hydrogen chloride degraded in the polyvinyl chloride to be inactivated, and further cannot achieve the ultraviolet-proof and oxidation-resistant functions.

Disclosure of Invention

The invention aims to provide a preparation method of an anti-ultraviolet agent for polyvinyl chloride.

The purpose of the invention can be realized by the following technical scheme:

a preparation method of an anti-ultraviolet agent for polyvinyl chloride specifically comprises the following steps:

step one, adding 50mmol of 4,4' -diphthalic anhydride and 200ml of NMP solvent into a three-neck flask, stirring and dissolving completely, dropwise adding 105-110mmol of 4-hydroxypiperidine hydrochloride, gradually heating to perform heat preservation reaction, naturally cooling to room temperature, adding 100-150ml of 10% sodium hydroxide aqueous solution, stirring at room temperature for 25-30min, adding ethyl acetate for extraction, collecting an organic phase, performing rotary evaporation to remove the solvent, washing with anhydrous ether, and drying to obtain an intermediate W1;

secondly, weighing 20mmol of the intermediate A, 22-25mmol of sodium hydroxide and 60-70% of ethanol water solution in mass fraction, stirring and dissolving completely, then adding 21-22mmol of magnesium chloride, stirring at room temperature for reaction, standing at room temperature for half an hour after the reaction is finished, performing suction filtration, washing with anhydrous ether, and drying to obtain the uvioresistant agent with the structure shown in the formula W;

the reaction process of the uvioresistant agent is as follows:

further, in the first step, the temperature of the heat-preservation reaction is 70-75 ℃.

Furthermore, in the first step, the reaction time is kept for 2-3 h.

Furthermore, in the second step, the reaction time is 1.5-2 h.

The invention has the beneficial effects that:

the invention provides a preparation method of an anti-ultraviolet agent for polyvinyl chloride, which comprises the steps of firstly carrying out ester exchange reaction on 4,4' -diphthalic anhydride and 4-hydroxypiperidine hydrochloride serving as raw materials to obtain an intermediate W1, then reacting the intermediate W1 with sodium hydroxide to form sodium salt, and carrying out double decomposition reaction on magnesium chloride to obtain the anti-ultraviolet agent W containing hindered amine and magnesium salt.

Of course, it is not necessary for any product in which the invention is practiced to achieve all of the above-described advantages at the same time.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.