阅读说明：本技术 一种硫醇基醚聚合物的合成方法 (Synthetic method of thiol ether polymer ) 是由 李锦� 张全成 李立杰 郑飞 季璐 于 2019-12-02 设计创作，主要内容包括：本发明公开了一种由巯基烷酸、硫代二丙酸、三羟基环氧丙烷聚醚为原料,采用酸性催化剂,进行酯化反应合成硫醇基聚醚方法。硫醇基醚聚合物可空气氧化制成单组份密封剂。该胶基密封剂耐水性、耐湿性、耐寒性优良,且具有价格低、施工方便、工艺性能好等特点,可广泛用于建筑嵌缝、门窗以及土木、造船及一般机械工业领域。(The invention discloses a method for synthesizing thiol polyether by esterification reaction of mercaptoalkanoic acid, thiodipropionic acid and trihydroxy propylene oxide polyether which are used as raw materials and an acidic catalyst. The thiol ether polymer can be air oxidized to form a one-component sealant. The glue base sealant has the characteristics of excellent water resistance, moisture resistance and cold resistance, low price, convenient construction, good process performance and the like, and can be widely applied to the fields of building caulking, doors and windows, civil engineering, shipbuilding and general mechanical industry.)

1. A method for synthesizing a thiol ether polymer, comprising the steps of:

the thiol ether polymer is prepared from mercaptoalkanoic acid, thiodipropionic acid and trihydroxy propylene oxide polyether through reflux dehydration esterification reaction in the presence of acid catalyst and toluene as solvent, alkali neutralization, filtering and vacuum evaporation.

2. The method of claim 1, wherein the thiol ether polymer is prepared by the steps of: the ratio of the carboxyl values of the mercaptoalkanoic acid and the thiodipropionic acid is 2: 1, and the ratio of the hydroxyl value of the trihydroxy propylene oxide polyether to the carboxyl values of the mercaptoalkanoic acid and the thiodipropionic acid is 1: 1-1.2.

3. The method of claim 1, wherein the thiol ether polymer is prepared by the steps of: the hydroxyl value of the trihydroxy propylene oxide polyether is 30-50 mgKOH/g.

4. The method of claim 1, wherein the thiol ether polymer is prepared by the steps of: the catalyst is benzenesulfonic acid, and the dosage of the benzenesulfonic acid is 0.5-2.0% (mass parts) of the dosage of trihydroxy propylene oxide polyether.

5. The method of claim 1, wherein the thiol ether polymer is prepared by the steps of: the temperature of the reflux dehydration reaction is 116-118 ℃, 147-149 ℃, and the time of the reflux dehydration reaction is 5-6 h.

6. The method of claim 1, wherein the thiol ether polymer is prepared by the steps of: the alkali used for neutralization is concentrated ammonia water and quicklime.

7. The method of claim 1, wherein the thiol ether polymer is prepared by the steps of: removing the salt by pressure filtration under the action of filter aid. The filter aid is perlite powder, and the addition amount of the filter aid is 1.5 percent (mass parts) of the filtrate.

Technical Field

The invention belongs to the technical field of high molecular polymer production, and particularly relates to a synthetic method of a thiol ether polymer.

Background

The thiol ether polymer is a liquid glue which contains ether bond, thioether bond and ester bond in the main chain and can be vulcanized at room temperature. The earliest developed products in the United states. Has no report in China. The thiol ether polymer can be air-oxidized to prepare a single-component sealant, and the glue base sealant has the characteristics of excellent water resistance, moisture resistance and cold resistance, low price, convenient construction, good process performance and the like, and can be widely applied to the fields of building caulking, doors and windows, civil engineering, shipbuilding and general mechanical industry. The polymer is reported to have excellent air heat aging resistance and water immersion heat aging resistance and longer service life than polysulfide rubber and industrial silicone rubber sealant when used together with liquid polysulfide rubber.

The invention adopts a synthetic route which takes the mercaptoalkanoic acid, the thiodipropionic acid and the trihydroxy propylene oxide polyether as main monomers to synthesize the thiol ether polymer, the reaction process is stable, the product quality is easy to control, and the raw materials are cheap and easy to obtain.

Disclosure of Invention

The invention aims to provide a process route for synthesizing a thiol ether polymer by using mercaptoalkanoic acid, thiodipropionic acid and trihydroxy propylene oxide polyether as main monomers. The thiol polyether is synthesized by esterification reaction with acid catalyst, and the thiol ether polymer with proper viscosity and proper molecular weight is synthesized by controlling the reaction process and effective post-treatment. Simple process, easy control of product quality, cheap and easily available raw materials and little environmental pollution. The molecular weight of the generated thiol ether polymer is large and is about 10000, but the viscosity is small and is close to Newtonian fluid. The product has very active SH groups and ester groups influenced by bonds, has the performance of automatic oxidation and vulcanization in the presence of air, can be prepared into a single-component sealant, and has very good ageing resistance, water resistance, weather resistance and good adhesion.

The invention discloses a synthetic method of a thiol ether polymer, which comprises the following steps:

the thiol ether polymer is prepared with mercaptoalkanoic acid, thiodipropionic acid and trihydroxy propylene oxide polyether in certain proportion as material and through reflux dewatering esterification in solvent under the action of acid catalyst, alkali neutralization of the esterification product, filtering and vacuum evaporation.

In the synthetic reaction of the thiol ether polymer, the ratio of the hydroxyl value of the mercaptoalkanoic acid to the carboxyl value of the thiodipropionic acid is 2: 1, and the ratio of the hydroxyl value of the trihydroxy propylene oxide polyether to the carboxyl values of the mercaptoalkanoic acid and the thiodipropionic acid is 1: 1-1.2.

In the synthetic reaction of the thiol ether polymer, the hydroxyl value of trihydroxy propylene oxide polyether is 30-50 mgKOH/g.

In the synthetic reaction of the thiol ether polymer, the used mercaptoalkanoic acid can be mercaptoacetic acid and mercaptopropionic acid.

The catalyst used in the synthetic reaction of the thiol ether polymer is benzenesulfonic acid, and the using amount of the benzenesulfonic acid is 0.5-2.0% (mass parts) of the using amount of trihydroxy propylene oxide polyether.

The solvent used in the synthesis reaction of the thiol ether polymer of the present invention is toluene or xylene.

In the synthetic reaction of the thiol ether polymer, the reflux dehydration reaction temperature is 116-118 ℃, and 147-149 ℃.

In the synthetic reaction of the thiol ether polymer, the reflux dehydration reaction time is 5-6 h.

In the synthetic reaction of the thiol ether polymer, the esterified liquid is neutralized by alkali to pH value of 7, and unreacted mercaptoalkanoic acid, thiodipropionic acid and catalyst benzenesulfonic acid are removed. The alkali is concentrated ammonia water and quicklime.

In the synthesis reaction of the thiol ether polymer, the neutralized esterification solution is subjected to pressure filtration under the action of a filter aid to remove the generated salt. The filter aid is perlite powder, and the addition amount of the filter aid is 1.5 percent (mass parts) of the filtrate.

In the synthetic reaction of the thiol ether polymer, the filtered filtrate adopts a film evaporator to remove the solvent, so that a finished product is obtained, and the yield is over 90 percent based on trihydroxy propylene oxide polyether.

The structural formula of the product is as follows:

the invention has the advantages that the thiol ether polymer is synthesized by adopting the mercaptoalkanoic acid, the thiodipropionic acid and the trihydroxy propylene oxide polyether as main monomers, the reaction process is stable, the product quality is easy to control, and the raw materials are cheap and easy to obtain. As SH groups and esters are very close, thiol groups are very active under the influence of bonds, and have the property of auto-oxidation vulcanization in the presence of air, but are quite stable if air is isolated, and can be stored for a long time. By utilizing the characteristic, the air oxygen-curable one-component sealant can be conveniently prepared. The air oxygen vulcanization single-component sealant has higher superiority than the moisture absorption single-component sealant, the vulcanization of the sealant is not influenced by temperature and humidity, and the sealant can be constructed and used all the year round.

Detailed Description