A low-viscosity environmentally friendly polyester heat-resistant plasticizer and preparation method thereof

Abstract

The invention belongs to the technical field of fine chemical production, and specifically relates to a low-viscosity environmentally friendly polyester heat-resistant plasticizer and a preparation method thereof. The preparation method comprises the following steps: mixing ethylene glycol and propylene glycol, preheating and stirring for 5-8 minutes, adding adipic acid and a catalyst for esterification, stirring for 3-5 hours at 160-180°C, then stirring for 1-2 hours at 200-220°C, adding a capping agent, stirring for 45-65 minutes at 210-220°C, and obtaining a polyester plasticizer. The obtained polyester plasticizer has good migration resistance and non-toxic characteristics, and can significantly improve the mechanical properties of polyvinyl chloride materials.

Description

Technical Field

[0001] The invention belongs to the technical field of fine chemical production, and specifically relates to a low-viscosity environmentally friendly polyester heat-resistant plasticizer and a preparation method thereof. Background Art

[0002] As a chemical substance widely used in industrial production, the core function of plasticizers is to weaken the secondary bonds between resin molecules, give the resin molecular bonds stronger mobility, reduce the degree of crystallization of resin molecules, thereby improving the plasticity of resin molecules, and then effectively enhance the flexibility and processability of plastics and other polymer materials, and optimize product performance. Traditional phthalate plasticizers have disadvantages such as mobility and volatility, which pose potential risks to the environment and health. Faced with this challenge, polyester heat-resistant plasticizers have become an ideal choice to replace traditional plasticizers with their more outstanding environmental performance and excellent thermal stability.

[0003] However, polyester heat-resistant plasticizers currently on the market generally have the defect of high viscosity, which seriously restricts their dispersion efficiency in polymer materials and the convenience of processing, and may even have adverse effects on the relevant properties of the final product. In view of this, it is urgent to develop a low-viscosity and environmentally friendly polyester heat-resistant plasticizer. This type of plasticizer can not only greatly optimize the processing performance of the material and effectively guarantee the quality of the final product, but also meet the increasingly stringent environmental protection regulations, and has extremely important practical application value and significance. Summary of the invention

[0004] In view of the deficiencies in the prior art, the present invention provides a low-viscosity, environmentally friendly polyester heat-resistant plasticizer and a preparation method thereof. The prepared plasticizer has excellent migration resistance, high temperature resistance and aging resistance.

[0005] In order to achieve the above object, the technical solution adopted by the present invention is: The present invention provides a method for preparing a low-viscosity environmentally friendly polyester heat-resistant plasticizer, comprising the following steps: Ethylene glycol and propylene glycol are mixed, preheated and stirred for 5-8 minutes, adipic acid and a catalyst are added for esterification reaction, stirred at 160-180°C for 3-5 hours, then stirred at 200-220°C for 1-2 hours, a capping agent is added, and stirred at 210-220°C for 45-65 minutes to obtain a polyester plasticizer.

[0006] Preferably, the mass ratio of ethylene glycol, propylene glycol, adipic acid and end-capping agent is 300-350:300-330:600-650:36-55.

[0007] Preferably, the capping agent is 2-propylheptanol and / or benzoic acid.

[0008] Preferably, the catalyst is at least one of tetraisooctyl titanate, dibutyltin oxide and antimony trioxide.

[0009] Preferably, the added amount of the catalyst is 1-2% of the total mass of ethylene glycol, propylene glycol and adipic acid.

[0010] Preferably, the viscosity of the polyester plasticizer at 25° C. is 800-1200 mPa·s.

[0011] Preferably, the acid value of the polyester plasticizer is not greater than 1.0 mgKOH / g.

[0012] Preferably, the preheating temperature is 80-90°C.

[0013] The invention also provides a low-viscosity environmentally friendly polyester heat-resistant plasticizer, which is prepared by the preparation method.

[0014] The present invention has the following beneficial effects: The invention mixes ethylene glycol and propylene glycol, and then reacts with adipic acid to produce a plasticizer for esterification, wherein the plasticizer exhibits good heat resistance and durability and has excellent oil resistance; wherein the introduction of ethylene glycol can improve the flexibility and low temperature resistance of the polyester plasticizer; the introduction of propylene glycol can give the polyester plasticizer better solubility and processing performance, and is helpful to improve the flexibility of the polyester plasticizer; the synergistic effect of ethylene glycol and propylene glycol participates in the esterification reaction to form a polyester segment, and is helpful to improve the durability and flexibility of the polyester plasticizer; and the end-capping agent is added in the later stage of the esterification reaction, so as to control the molecular weight of the polyester plasticizer, so that the polyester plasticizer has a suitable molecular weight distribution and processing performance, and meets different application requirements.

[0015] The plasticizer prepared by the invention is a non-phthalate plasticizer, which is non-toxic and pollution-free. The preparation process is simple and easy. While significantly reducing the reaction energy consumption, the difficulty of separation and purification is also greatly reduced. The prepared polyester plasticizer exhibits excellent compatibility with polyvinyl chloride, can greatly optimize the mechanical properties of polyvinyl chloride materials, and effectively enhance key indicators such as the strength and toughness of the materials, thereby broadening the application scope and potential of polyvinyl chloride materials. DETAILED DESCRIPTION

[0016] Unless otherwise specified, the materials and reagents used in the present invention can be obtained from commercial sources. The specific description is as follows: Ethylene glycol, purchased from Wuxi Jiaxi Chemical Co., Ltd.; 2-propylheptanol, CAS No.: 10042-59-8, density: 0.828 g / cm 3, purchased from Shandong Qiyun Chemical Technology Co., Ltd.; adipic acid, CAS No.: 124-04-9, purchased from Anhui Kemi Technology Co., Ltd.; propylene glycol, CAS No.: 57-55-6, purchased from Jinan Chengyijia Chemical Co., Ltd.; tetraethyl hexyl titanate, purchased from Shandong Dongfang Riqi New Materials Co., Ltd., CAS No.: 1070-10-6; dibutyl tin oxide, purchased from Jinan Lanjue Trading Co., Ltd., white powder; antimony trioxide, purchased from Langfang Pengcai Fine Chemical Co., Ltd., analytical grade, content ≥99%.

[0017] Example 1 A method for preparing a low-viscosity environmentally friendly polyester heat-resistant plasticizer comprises the following steps: Ethylene glycol and propylene glycol are mixed, stirred at 80°C and 100 rpm for 5 minutes, adipic acid and a catalyst are added for esterification reaction, stirred at 160°C and 150 rpm for 3 hours, then stirred at 200°C and 100 rpm for 1 hour, and then a capping agent is added, stirred at 210°C and 100 rpm for 45 minutes to obtain a polyester plasticizer; wherein the mass ratio of ethylene glycol, propylene glycol, adipic acid and the capping agent is 300:300:600:36, the amount of the catalyst added is 1% of the total mass of ethylene glycol, propylene glycol and adipic acid, the capping agent is 2-propylheptanol, and the catalyst is tetraisooctyl titanate.

[0018] Example 2 A method for preparing a low-viscosity environmentally friendly polyester heat-resistant plasticizer comprises the following steps: Ethylene glycol and propylene glycol are mixed, stirred at 90°C and 200 rpm for 8 minutes, adipic acid and a catalyst are added for esterification reaction, stirred at 180°C and 200 rpm for 5 hours, then stirred at 220°C and 200 rpm for 2 hours, and then a capping agent is added, and stirred at 220°C and 200 rpm for 65 minutes to obtain a polyester plasticizer; wherein the mass ratio of ethylene glycol, propylene glycol, adipic acid and the capping agent is 350:330:650:55, the amount of the catalyst added is 2% of the total mass of ethylene glycol, propylene glycol and adipic acid, the capping agent is benzoic acid, and the catalyst is dibutyltin oxide.

[0019] Example 3 A method for preparing a low-viscosity environmentally friendly polyester heat-resistant plasticizer comprises the following steps: Ethylene glycol and propylene glycol are mixed, stirred at 85°C and 150 rpm for 7 minutes, adipic acid and a catalyst are added for esterification reaction, stirred at 170°C and 180 rpm for 4 hours, then stirred at 210°C and 150 rpm for 1.5 hours, and then a capping agent is added, stirred at 215°C and 150 rpm for 55 minutes to obtain a polyester plasticizer; wherein the mass ratio of ethylene glycol, propylene glycol, adipic acid and capping agent is 347:320:620:46, the amount of catalyst added is 1.5% of the total mass of ethylene glycol, propylene glycol and adipic acid, the capping agent is benzoic acid, and the catalyst is antimony trioxide.

[0020] Comparative Example 1 A method for preparing a low-viscosity environmentally friendly polyester heat-resistant plasticizer comprises the following steps: Ethylene glycol, adipic acid and a catalyst are mixed, stirred at 160°C and 150 rpm for 3 hours, then stirred at 200°C and 100 rpm for 1 hour, and then a capping agent is added, and stirred at 210°C and 100 rpm for 45 minutes to obtain a polyester plasticizer; wherein the mass ratio of ethylene glycol, adipic acid and the capping agent is 600:600:36, the amount of the catalyst added is 1% of the total mass of ethylene glycol, propylene glycol and adipic acid, the capping agent is 2-propylheptanol, and the catalyst is tetraisooctyl titanate.

[0021] Comparative Example 2 A method for preparing a low-viscosity environmentally friendly polyester heat-resistant plasticizer comprises the following steps: Propylene glycol, adipic acid and a catalyst are mixed, stirred at 160°C and 150 rpm for 3 hours, then stirred at 200°C and 100 rpm for 1 hour, and then a capping agent is added, and stirred at 210°C and 100 rpm for 45 minutes to obtain a polyester plasticizer; wherein the mass ratio of propylene glycol, adipic acid and the capping agent is 600:600:36, the amount of the catalyst added is 1% of the total mass of ethylene glycol, propylene glycol and adipic acid, the capping agent is 2-propylheptanol, and the catalyst is tetraisooctyl titanate.

[0022] Comparative Example 3 A method for preparing a low-viscosity environmentally friendly polyester heat-resistant plasticizer comprises the following steps: Ethylene glycol and propylene glycol are mixed, stirred at 80°C and 100 rpm for 5 minutes, adipic acid and a catalyst are added for esterification reaction, stirred at 160°C and 150 rpm for 3 hours, and then stirred at 200°C and 100 rpm for 1 hour to obtain a polyester plasticizer; wherein the mass ratio of ethylene glycol, propylene glycol and adipic acid is 300:300:600, the amount of catalyst added is 1% of the total mass of ethylene glycol, propylene glycol and adipic acid, and the catalyst is tetraisooctyl titanate.

[0023] Comparative Example 4 In this comparative example, a commercially available plasticizer, dioctyl phthalate, is provided, and the manufacturer is Liaocheng Hengyu Environmental Protection Technology Co., Ltd.

[0024] Performance Testing The polyester plasticizers obtained in Examples 1-3 and Comparative Examples 1-4 are used to prepare polyvinyl chloride resins. The specific preparation method is as follows: The raw materials were weighed and put into a mixer for uniform mixing at a mixing temperature of 90° C. The raw materials were then extruded into a polyvinyl chloride test piece using a twin-screw extruder at a temperature of 180° C. and a speed of 60 rpm.

[0025] The recipe table is as follows: Table 1 PVC test piece formula

[0026] Shore hardness is tested according to the national standard GB / T2411-2008; The tensile strength and elongation at break are tested according to the national standard GB / T1040.1-2018; Air aging conditions: storage at 136°C for 168h; Oil aging resistance conditions: immersion in mineral oil for 168h at 60℃; The performance test results of each test piece are shown in Table 2.

[0027] Table 2 Performance test results of Examples 1-3 and Comparative Examples 1-4

[0028] It can be seen from the test results in Table 2 that the polyester plasticizer prepared in the present invention helps to improve the hardness and tensile strength of polyvinyl chloride materials. Compared with commercially available plasticizers, the polyester plasticizer of the present invention has better migration resistance.

[0029] Table 3 Performance test results of Examples 1-3 and Comparative Examples 1-4 after aging

[0030] It can be seen from the test results in Table 3 that the embodiments prepared in the present invention have excellent aging resistance.

[0031] This specific embodiment is merely an explanation of the present invention and is not a limitation of the present invention. After reading this specification, those skilled in the art may make non-creative modifications to the present embodiment as needed. However, as long as they are within the scope of the claims of the present invention, they are protected by the patent law.

Claims

1. A method for preparing a low-viscosity environmentally friendly polyester heat-resistant plasticizer, characterized in that: The following steps are involved: Ethylene glycol and propylene glycol are mixed, preheated and stirred for 5-8 minutes, adipic acid and a catalyst are added for esterification reaction, stirred at 160-180°C for 3-5 hours, then stirred at 200-220°C for 1-2 hours, a capping agent is added, and stirred at 210-220°C for 45-65 minutes to obtain a polyester plasticizer.

2. The method for preparing the low-viscosity environmentally friendly polyester heat-resistant plasticizer according to claim 1, characterized in that: The mass ratio of the ethylene glycol, propylene glycol, adipic acid and the end-capping agent is 300-350:300-330:600-650:36-55.

3. The method for preparing the low-viscosity environmentally friendly polyester heat-resistant plasticizer according to claim 1, characterized in that: The end-capping agent is 2-propylheptanol and / or benzoic acid.

4. The method for preparing the low-viscosity environmentally friendly polyester heat-resistant plasticizer according to claim 1, characterized in that: The catalyst is at least one of tetraisooctyl titanate, dibutyltin oxide and antimony trioxide.

5. The method for preparing the low-viscosity environmentally friendly polyester heat-resistant plasticizer according to claim 1, characterized in that: The added amount of the catalyst is 1-2% of the total mass of ethylene glycol, propylene glycol and adipic acid.

6. The method for preparing the low-viscosity environmentally friendly polyester heat-resistant plasticizer according to claim 1, characterized in that: The viscosity of the polyester plasticizer at 25° C. is 800-1200 mpa·s.

7. The method for preparing the low-viscosity environmentally friendly polyester heat-resistant plasticizer according to claim 1, characterized in that: The acid value of the polyester plasticizer is not greater than 1.0 mgKOH / g.

8. The method for preparing the low-viscosity environmentally friendly polyester heat-resistant plasticizer according to claim 1, characterized in that: The preheating temperature is 80-90°C.

9. A low-viscosity environmentally friendly polyester heat-resistant plasticizer, characterized in that: Prepared according to the preparation method according to any one of claims 1 to 8.

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