阅读说明：本技术 一种由乙交酯-ε-己内酯共聚物制备聚酯多元醇的方法 (Method for preparing polyester polyol from glycolide-epsilon-caprolactone copolymer ) 是由 于在乾 刘江宁 张龙 于 2021-09-24 设计创作，主要内容包括：本发明提供一种乙交酯-ε-己内酯共聚物基聚酯多元醇的制备方法,由于聚乙交酯和聚ε-己内酯均为绿色可降解材料,故该聚酯多元醇属于绿色可降解材料,以乙交酯、ε-己内酯为原料、1,4-丁二醇为引发剂、辛酸亚锡为催化剂,通过缩聚反应制备聚酯多元醇。在适当的缩聚反应条件下,所得聚酯多元醇羟值266.5 mgKOH/g,酸值4.8 mgKOH/g,含水量0.3％。所制备原料的技术指标完全满足合成可降聚氨酯泡沫材料的要求。本发明提供的制备聚酯多元醇的方法具有工艺简单,操作方便,通过改变单体原料的比例可以获得不同性能的聚酯多元醇产品。(The invention provides a preparation method of glycolide-epsilon-caprolactone copolymer-based polyester polyol, which is characterized in that glycolide and poly-epsilon-caprolactone are both green degradable materials, so that the polyester polyol belongs to the green degradable materials, and the polyester polyol is prepared by taking the glycolide and the epsilon-caprolactone as raw materials, 1, 4-butanediol as an initiator and stannous octoate as a catalyst through a polycondensation reaction. Under proper polycondensation reaction conditions, the obtained polyester polyol has a hydroxyl value of 266.5 mgKOH/g, an acid value of 4.8 mgKOH/g and a water content of 0.3 percent. The technical indexes of the prepared raw materials completely meet the requirements of synthesizing degradable polyurethane foam materials. The method for preparing the polyester polyol has the advantages of simple process and convenient operation, and polyester polyol products with different properties can be obtained by changing the proportion of the monomer raw materials.)

1. A preparation method of polyglycolide-epsilon-caprolactone copolymer based polyester polyol is characterized by comprising the following steps: adding glycolide and epsilon-caprolactone monomers with certain mass into a three-opening glass reactor, then adding 1, 4-butanediol and stannous octoate with certain mass, introducing nitrogen to remove air in the reactor, heating a reaction system to a certain temperature, reacting for 8-20 hours at constant temperature, and cooling to obtain the polyglycolide-epsilon-caprolactone copolymer-based polyester polyol.

2. The method for preparing polyester polyol by using glycolide and epsilon-caprolactone as raw materials according to claim 1, wherein the method comprises the following steps: the mass ratio of glycolide to epsilon-caprolactone is 1: 3-5; the dosage of the 1, 4-butanediol accounts for 10.0 to 20.0 percent of the total mass of the monomers.

3. The method for preparing polyester polyol by using glycolide and epsilon-caprolactone as raw materials according to claim 1, wherein the method comprises the following steps: the catalyst stannous octoate is a green additive, and the stannous octoate is a food additive approved by FDA in the United states.

4. The method for preparing polyester polyol by using glycolide and epsilon-caprolactone as raw materials according to claim 1, wherein the method comprises the following steps: the reaction temperature is 120-160 ℃, and the reaction time is 8-20 hours.

Technical Field

The invention belongs to the field of synthesis of environment-friendly materials, and particularly relates to a preparation method of polyglycolide-epsilon-caprolactone copolymer-based polyester polyol.

Background

Polyurethane (PU), the full name of which is polyurethane, is formed by the polycondensation of isocyanates and polyols. The polyurethane is invented in the 30 s of the 20 th century, and through eighty years of technical development, the material is widely applied to the fields of home furnishing, buildings, daily necessities, traffic, household appliances and the like. The polyurethane product mainly comprises: foamed plastic, elastomers, fibers, coatings, adhesives, sealants and the like, wherein the foamed plastic accounts for the largest proportion and is the sixth highest polymer material in the world at present.

As the amount of polyurethane used has increased, the amount of waste polyurethane products and materials has increased dramatically, and the disposal of these waste polyurethane materials has become a worldwide problem. At present, typical treatment methods of polyurethane wastes include incineration and landfill, but the treatment methods seriously pollute air and occupy a large amount of valuable land resources on one hand, and on the other hand, the treatment method causes difficult aftertreatment and high cost due to the non-degradability of polyurethane. Therefore, the development of degradable polyurethane materials is urgently needed to alleviate the increasingly serious problems of environmental pollution and resource waste caused by the disposal of degradable polyurethane materials after large-scale use.

At present, the key raw materials for polyurethane synthesis, namely isocyanate or polyisocyanate and polyol, are all from petroleum and are not degradable. The development of degradable polyurethanes is therefore currently mainly focused on the synthesis of degradable polyols. At present, degradable polyols are mainly classified into 3 types, namely (1) natural polymer type, (2) vegetable oil-based type and (3) molecular chain design type.

The synthesis method of the degradable polyurethane mainly comprises two aspects, namely, on one hand, the degradable polyurethane is prepared by reacting hydroxyl in natural macromolecules with isocyanate, and on the other hand, the degradable polyurethane is prepared by reacting synthesized polyether polyol or polyester polyol with isocyanate or polyisocyanate. The degradable polyurethane material can be degraded after being used, so that the environment can not be polluted, and the application prospect is wide.

The degradable polyurethane material has wide application prospect, but still has some problems to be solved, namely (1) the production cost problem. The preparation technology is not perfect enough, the product price is higher than that of the traditional polyurethane material, and the large-scale popularization and application are limited; (2) the degradation speed is problem. How to make the degradation polyurethane have different degradation rates in different application scenes still needs to be further solved.

Polyester polyol is one of main raw materials for synthesizing polyurethane, and is mainly prepared from dicarboxylic acid, dihydric alcohol and the like through polycondensation reaction.

The preparation method comprises the steps of using sunflower seed oil as a raw material, carrying out epoxidation under the combined action of glacial acetic acid and hydrogen peroxide to prepare a sunflower seed oil-based epoxidation product (SOEP), and carrying out an epoxy ring-opening reaction on the sunflower seed oil-based epoxidation product and diethanol amine by using lithium hydroxide as a catalyst to prepare sunflower seed oil-based polyol (SOPOL). (Synthesis and characterization of Violin, Yangyizi, Yongqiwen, Weandong, Liuqi, sunflower seed oil-based polyol [ J ] polyurethane industry, 2020(2): 19-21.)

Adding sebacic acid, ethylene glycol and glycerol into a four-mouth bottle, heating until the sebacic acid is completely melted, adding a certain proportion of lignin, introducing nitrogen, heating to 140 ℃, reacting for 3h, adding a certain amount of antimony trioxide, heating to 160 ℃, reacting for 3h, reacting for 0.5h under the vacuum degree of-0.064 MPa, reacting for 0.5h under the vacuum degree of-0.088 MPa, and cooling to room temperature to obtain the lignin-based polyester polyol. (Zhongzhi, HerSHAN, Liutong, Chongwei, Synthesis and characterization of Lignin-based polyester polyol [ J ] chemical and adhesive 2015(3):171-

High-victory polyester polyol is prepared from soybean oil, phthalic anhydride, terephthalic acid and small molecular alcohol through esterification-ester exchange reaction. Adding a certain amount of terephthalic acid, phthalic anhydride, diethylene glycol and glycerol into a 1000 mL four-neck flask, starting stirring and heating, and carrying out esterification reaction under the protection of nitrogen. When the reaction temperature reaches 150-160 ℃, keeping for 2-3h, raising the temperature to 230 ℃ by program, reacting for about 8h at 230 ℃, and adding soybean oil and a certain amount of tetrabutyl titanate catalyst to perform polycondensation exchange reaction. (synthesis of Highe, Liu Guanchen, Yangshou apple, Zhang Yong, Yaojixu, Soybean oil based polyester polyol and its application in polyurethane foam [ J ] chemical propellant and high molecular material, 2020(3): 58-61.)

The natural polymer is used as the polyalcohol to replace the traditional petroleum-based product, so that the consumption of non-renewable resources, namely petroleum, is reduced, the problem that the petroleum-based product is not degradable is solved, and the raw material source is wide and environment-friendly. However, natural polymer polyols using sunflower seed oil, soybean oil and other oils as raw materials have practical problems of high raw material price, unstable quality, and only partial replacement of polyols for use, which limits further popularization, and therefore, development of molecular design type environment-friendly polyols has obvious practical requirements.

Disclosure of Invention

Aiming at the problems, the invention provides a method for preparing polyester polyol by taking glycolide and epsilon-caprolactone as raw materials, which takes glycolide and epsilon-caprolactone as monomers, 1, 4-butanediol as a capping reagent, stannous octoate as a catalyst, and adopts heating and nitrogen gas isolation to isolate air to obtain the polyester polyol taking a polyglycolide-epsilon-caprolactone copolymer as a main chain through a polymerization reaction.

The invention adopts the following technical scheme:

a method for preparing polyester polyol by taking glycolide and epsilon-caprolactone as main raw materials adopts a melt polymerization process technology. Glycolide, an epsilon-caprolactone monomer, 1, 4-butanediol and stannous octoate are sequentially added into a three-port glass reactor according to a proportion. Firstly, nitrogen is introduced for a plurality of minutes to exhaust the air in the reactor, then the system is heated to the specified temperature and reacts for 8 to 20 hours at the temperature of 120 ℃ and 160 ℃ to obtain the polyglycolide-epsilon-caprolactone copolymer polyester polyol.

The raw materials are glycolide (self-made) and epsilon-caprolactone (analytically pure); m (glycolide): m (. epsilon. -caprolactone) =1:3-5, preferably 1: 3.5-4.5.

The catalyst is stannous octoate, and the addition amount of the catalyst is 1.0-10.0 percent of the total mass of the monomers, preferably 3.0-5.0 percent.

The end-capping agent is 1, 4-butanediol, the amount added is 10.0-20.0%, preferably 12.0-15.0% of the total mass of the monomers.

The reaction temperature is between 120 ℃ and 160 ℃, and preferably between 130 ℃ and 150 ℃.

Polymerizing for 8-20h, preferably 8-12h under the condition of air exclusion

The invention has the beneficial effects that:

the raw materials and the auxiliary agents are nontoxic and harmless: stannous octoate which can be used as a food additive is used as a catalyst, and glycolide and epsilon-caprolactone are harmless raw materials.

Secondly, by adjusting the proportion of monomer glycolide and epsilon-caprolactone and the addition of 1, 4-butanediol, polyester polyols with different molecular weights and different hydroxyl values can be obtained, so that polyurethane materials with different performances can be obtained by reacting with isocyanate.

And fourthly, the preparation process is clean, and no by-product or pollutant is generated. The obtained polyester polyol has a hydroxyl value of 266.5 mgKOH/g, an acid value of 4.8 mgKOH/g and a water content of 0.3 percent, and meets the quality requirements of polyurethane foam on the polyester polyol.

Detailed Description

In order to make the technical solutions and advantages of the present invention clearer, the following will clearly and completely describe the technical solutions of the present invention with reference to the embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments of the present invention without making any creative effort, shall fall within the protection scope of the present invention.

Example 1

Adding 2.3g (20mmol) of glycolide, 8.8g (80mmol) of epsilon-caprolactone, 1.8g (20mmol) of 1, 4-butanediol and 0.1g of stannous octoate into a 50ml three-port glass reactor provided with a stirring, heating and temperature control device and an air vent, introducing nitrogen for 10-15 minutes to exhaust air in the reactor before reaction, heating the system to 140 ℃, reacting for 8 hours, and then cooling to obtain a polyester polyol product. The polyester polyol was found to have a hydroxyl value of 123.4 mgKOH/g and an acid value of 9.6 mgKOH/g.

Example 2

Adding 2.3g (20mmol) of glycolide, 8.8g (80mmol) of epsilon-caprolactone, 3.6g (40mmol) of 1, 4-butanediol and 0.1g of stannous octoate into a 50ml three-port glass reactor provided with a stirring, heating and temperature control device and an air vent, introducing nitrogen for 10-15 minutes to exhaust air in the three-port glass reactor before reaction, heating the system to 140 ℃, reacting for 8 hours, and then cooling to obtain a polyester polyol product. The polyester polyol was found to have a hydroxyl value of 266.5 mgKOH/g and an acid value of 4.8 mgKOH/g.

Example 3

1.2g (10mmol) of glycolide, 9.9g (90mmol) of epsilon-caprolactone, 1.8g (20mmol) of 1, 4-butanediol and 0.1g of stannous octoate are added into a 50ml three-port glass reactor provided with a stirring, heating and temperature control device and an air vent, nitrogen is introduced into the three-port glass reactor for 10-15 minutes before reaction to exhaust air in the three-port glass reactor, then the system is heated to 140 ℃, and the temperature is reduced after reaction for 8 hours to obtain a polyester polyol product, wherein the hydroxyl value of the polyester polyol is determined to be 173.9 mgKOH/g, and the acid value is 7.8 mgKOH/g.

Example 4

3.5g (30mmol) of glycolide, 8.5g (70mmol) of epsilon-caprolactone, 3.6g (40mmol) of 1, 4-butanediol and 0.1g of stannous octoate are added into a 50ml three-port glass reactor provided with a stirring, heating and temperature control device and an air vent, nitrogen is introduced into the three-port glass reactor for 10-15 minutes before reaction to exhaust air in the three-port glass reactor, then the system is heated to 140 ℃, and the temperature is reduced after reaction for 8 hours to obtain a polyester polyol product, wherein the hydroxyl value of the polyester polyol is determined to be 230 mgKOH/g, and the acid value is 13.2 mgKOH/g.

Example 5

3.5g (30mmol) of glycolide, 8.2g (70mmol) of epsilon-caprolactone, 3.6g (40mmol) of 1, 4-butanediol and 0.1g of stannous octoate are added into a 50ml three-port glass reactor provided with a stirring, heating and temperature control device and an air vent, nitrogen is introduced into the three-port glass reactor for 10-15 minutes before reaction to exhaust air in the three-port glass reactor, then the system is heated to 140 ℃, the temperature is reduced after reaction for 4 hours to obtain a polyester polyol product, and the hydroxyl value of the polyester polyol is determined to be 230.0 mgKOH/g and the acid value is determined to be 123.2 mgKOH/g.

Example 6

Adding 2.3g (20mmol) of glycolide, 8.8g (80mmol) of epsilon-caprolactone, 2.7g (30mmol) of 1, 4-butanediol and 0.1g of stannous octoate into a 50ml three-port glass reactor provided with a stirring, heating and temperature control device and an air vent, introducing nitrogen for 10-15 minutes to exhaust air in the three-port glass reactor before reaction, heating the system to 140 ℃, reacting for 8 hours, and cooling to obtain a polyester polyol product, wherein the hydroxyl value of the polyester polyol is determined to be 179.5 mgKOH/g, and the acid value is 4.2 mgKOH/g.

Application example 1

5.0g of the prepared polyester polyol (example 2), 5.0g of 4110 g of polyether polyol, a proper amount of silicone oil, distilled water and diisobutyltin dilaurate were placed in a 250ml plastic beaker and stirred at high speed to mix the materials uniformly, and then the mixture was added with isopropyl alcoholAnd 8.2g of cyanate ester, stirring at a high speed until all materials are uniformly mixed, stopping stirring, standing for a few minutes, and curing for 48 hours to obtain the polyurethane rigid foam material. The apparent density of the polyurethane foam is 50.5Kg/m³The compressive strength is 150KPa, and the performance index requirement of the polyurethane thermal insulation material is met.

The above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present invention.