阅读说明：本技术 一种低气味甲基硫醇锡稳定剂的制备工艺 (Preparation process of low-odor methyl tin mercaptide stabilizer ) 是由 祁磊磊 于 2020-08-04 设计创作，主要内容包括：本发明公开了一种低气味甲基硫醇锡稳定剂的制备工艺,包括以下步骤：(1)制得催化剂铵盐；(2)制得二甲基二氯化锡和一甲基三氯化锡混合物；(3)制得低气味甲基硫醇锡稳定剂。本发明与现有技术相比的优点是：在反应过程中利用氧化铬催化剂在COO-键位和多元醇键位中间植入硅键,并且减少了酯中碳键的数量,在性能上保留了原有的热稳定性、透明性、相容性以及环保性能,并且在气味上,大大改善了原有的臭味,使得最终制品被用户接受。(The invention discloses a preparation process of a low-odor methyltin mercaptide stabilizer, which comprises the following steps: (1) preparing catalyst ammonium salt; (2) to prepare a mixture of dimethyltin dichloride and monomethyl tin trichloride; (3) the low-odor methyl tin mercaptide stabilizer is prepared. Compared with the prior art, the invention has the advantages that: in the reaction process, a silicon bond is implanted between a COO-bond and a polyol bond by using a chromium oxide catalyst, the number of carbon bonds in ester is reduced, the original thermal stability, transparency, compatibility and environmental protection performance are kept in performance, the original odor is greatly improved in smell, and the final product is accepted by users.)

1. A preparation process of a low-odor methyltin mercaptide stabilizer is characterized by comprising the following steps of: the method comprises the following steps:

(1) preparing catalyst ammonium salt: adding absolute ethyl alcohol into a stainless steel reaction kettle, introducing trimethylamine, dissolving and absorbing, heating to 80 ℃, stirring and introducing methyl chloride gas, controlling the temperature to be 115 ℃, controlling the pressure to be 0.8-1.0MPa, reacting for 20 hours, cooling, centrifugally filtering to obtain a light yellow or white crystalline compound, namely obtaining catalyst ammonium salt, taking out and placing into a bottle for later use;

(2) preparing a mixture of dimethyltin dichloride and monomethyl tin trichloride: adding 3.5kg of tin sheets and 0.1kg of catalyst ammonium salt into a stainless steel reaction kettle, heating to 150 ℃, introducing methyl chloride gas, keeping the kettle pressure at 1.2-1.5MPa, heating to 200 ℃, adding the methyl chloride gas until the pressure is not reduced, reducing the pressure to 1MPa after about 3 hours, adding 1.0kg of stannic chloride, introducing the methyl chloride gas for continuous reaction, keeping the kettle pressure at 1.2-1.5MPa, and reacting for 1.5 hours; after cooling, emptying the residual gas to obtain 5.5kg of white acicular crystal compound which is a mixture of dimethyltin dichloride and monomethyl tin trichloride in a weight ratio of 78:22, taking out and putting into a bottle for later use;

(3) preparing a low-odor methyl tin mercaptide stabilizer: adding 1.2kg of acetic acid, 2.04kg of hexanol and 1.56kg of metasilicic acid into a stainless steel reaction kettle, adding a catalyst of chromium oxide to prepare silicon amyl acetate, diluting with petroleum ether, adding a prepared 50% sodium bicarbonate solution, stirring, then dropwise adding 4.4kg of the mixture prepared in the step (2), reacting at room temperature and normal pressure for 2 hours, preserving the temperature at 70 ℃ by using a water bath after the reaction is finished, preserving the temperature for 2 hours, removing a lower water layer, washing with water for two times, heating to 100 ℃, recovering the petroleum ether solvent by using a condenser, and desolventizing for 1 hour to obtain the final transparent oily low-odor methyl tin mercaptide stabilizer.

Technical Field

The invention relates to a stabilizer, in particular to a preparation process of a low-odor methyltin mercaptide stabilizer.

Background

Conventional methyl tin mercaptides are predominantly mixtures of dimethyl tin mercaptide and monomethyl tin mercaptide. Has excellent heat stabilizer performance, and no other type of PVC stabilizer can exceed the heat stabilizer in terms of heat stability. Excellent transparency: by adopting the formula of the methyl tin mercaptide heat stabilizer, a crystallized product can be obtained, and the whitening phenomenon can not occur. The product is nontoxic: the methyl tin mercaptide is a nontoxic green environment-friendly stabilizer. Good compatibility: the methyltin mercaptide stabilizer is well compatible with the resin and is easily dispersible. The PVC film is widely applied to the industry of transparent PVC products. However, conventional methyltin mercaptides are difficult for manufacturers and users of end products to accept the odor of conventional methyltin mercaptides, and individually cause vomiting. Therefore, the development of a preparation process of a low-odor methyltin mercaptide stabilizer is a problem to be solved by those skilled in the art.

Disclosure of Invention

The invention provides a preparation process of a low-odor methyltin mercaptide stabilizer for solving the defects.

The above object of the present invention is achieved by the following technical means: a preparation process of a low-odor methyltin mercaptide stabilizer is characterized by comprising the following steps of: the method comprises the following steps:

(1) preparing catalyst ammonium salt: adding absolute ethyl alcohol into a stainless steel reaction kettle, introducing trimethylamine, dissolving and absorbing, heating to 80 ℃, stirring and introducing methyl chloride gas, controlling the temperature to be 115 ℃, controlling the pressure to be 0.8-1.0MPa, reacting for 20 hours, cooling, centrifugally filtering to obtain a light yellow or white crystalline compound, namely obtaining catalyst ammonium salt, taking out and placing into a bottle for later use;

(2) preparing a mixture of dimethyltin dichloride and monomethyl tin trichloride: adding 3.5kg of tin sheets and 0.1kg of catalyst ammonium salt into a stainless steel reaction kettle, heating to 150 ℃, introducing methyl chloride gas, keeping the kettle pressure at 1.2-1.5MPa, heating to 200 ℃, adding the methyl chloride gas until the pressure is not reduced, reducing the pressure to 1MPa after about 3 hours, adding 1.0kg of stannic chloride, introducing the methyl chloride gas for continuous reaction, keeping the kettle pressure at 1.2-1.5MPa, and reacting for 1.5 hours; after cooling, emptying the residual gas to obtain 5.5kg of white acicular crystal compound which is a mixture of dimethyltin dichloride and monomethyl tin trichloride in a weight ratio of 78:22, taking out and putting into a bottle for later use;

(3) preparing a low-odor methyl tin mercaptide stabilizer: adding 1.2kg of acetic acid, 2.04kg of hexanol and 1.56kg of metasilicic acid into a stainless steel reaction kettle, adding a catalyst of chromium oxide to prepare silicon amyl acetate, diluting with petroleum ether, adding a prepared 50% sodium bicarbonate solution, stirring, then dropwise adding 4.4kg of the mixture prepared in the step (2), reacting at room temperature and normal pressure for 2 hours, preserving the temperature at 70 ℃ by using a water bath after the reaction is finished, preserving the temperature for 2 hours, removing a lower water layer, washing with water for two times, heating to 100 ℃, recovering the petroleum ether solvent by using a condenser, and desolventizing for 1 hour to obtain the final transparent oily low-odor methyl tin mercaptide stabilizer.

The stabilizer of the invention has a heat stabilizing effect in PVC products, such as agricultural drainage pipes, household gas pipes, furniture edge sealing strips, advertising cloth, soles and other industries, and can be widely applied. In particular, the transparency exhibited by the stabilizer is an excellent choice in the transparent product industry.

Compared with the prior art, the invention has the advantages that: in the reaction process, a silicon bond is implanted between a COO-bond and a polyol bond by using a chromium oxide catalyst, the number of carbon bonds in ester is reduced, the original thermal stability, transparency, compatibility and environmental protection performance are kept in performance, the original odor is greatly improved in smell, and the final product is accepted by users.

Detailed Description

The present invention will be described in more detail with reference to examples.

The invention relates to a preparation process of a low-odor methyltin mercaptide stabilizer, which comprises the following steps of:

(1) preparing catalyst ammonium salt: adding absolute ethyl alcohol into a stainless steel reaction kettle, introducing trimethylamine, dissolving and absorbing, heating to 80 ℃, stirring and introducing methyl chloride gas, controlling the temperature to be 115 ℃, controlling the pressure to be 0.8-1.0MPa, reacting for 20 hours, cooling, centrifugally filtering to obtain a light yellow or white crystalline compound, namely obtaining catalyst ammonium salt, taking out and placing into a bottle for later use;

(2) preparing a mixture of dimethyltin dichloride and monomethyl tin trichloride: adding 3.5kg of tin sheets and 0.1kg of catalyst ammonium salt into a stainless steel reaction kettle, heating to 150 ℃, introducing methyl chloride gas, keeping the kettle pressure at 1.2-1.5MPa, heating to 200 ℃, adding the methyl chloride gas until the pressure is not reduced, reducing the pressure to 1MPa after about 3 hours, adding 1.0kg of stannic chloride, introducing the methyl chloride gas for continuous reaction, keeping the kettle pressure at 1.2-1.5MPa, and reacting for 1.5 hours; after cooling, emptying the residual gas to obtain 5.5kg of white acicular crystal compound which is a mixture of dimethyltin dichloride and monomethyl tin trichloride in a weight ratio of 78:22, taking out and putting into a bottle for later use;

(3) preparing a low-odor methyl tin mercaptide stabilizer: adding 1.2kg of acetic acid, 2.04kg of hexanol and 1.56kg of metasilicic acid into a stainless steel reaction kettle, adding a catalyst of chromium oxide to prepare silicon amyl acetate, diluting with petroleum ether, adding a prepared 50% sodium bicarbonate solution, stirring, then dropwise adding 4.4kg of the mixture prepared in the step (2), reacting at room temperature and normal pressure for 2 hours, preserving the temperature at 70 ℃ by using a water bath after the reaction is finished, preserving the temperature for 2 hours, removing a lower water layer, washing with water for two times, heating to 100 ℃, recovering the petroleum ether solvent by using a condenser, and desolventizing for 1 hour to obtain the final transparent oily low-odor methyl tin mercaptide stabilizer.

The above description is only an embodiment of the present invention, and not intended to limit the scope of the present invention, and all modifications of equivalent structures and equivalent processes performed by the present invention in the specification and the content of the embodiment, or directly or indirectly applied to other related technical fields, are included in the scope of the present invention.