CN-122011244-A - Compound external electron donor for preparing polypropylene, preparation method thereof and polypropylene material

Abstract

The invention belongs to the technical field of modified catalysts, and relates to a compound external electron donor for preparing polypropylene, a preparation method thereof and a polypropylene material. The invention discloses a compound external electron donor for preparing polypropylene based on modification of a silane coupling agent, which is prepared by carrying out compound modification on a polypropylene catalyst and a specific silane coupling agent in white oil and/or vaseline medium, and the compound external electron donor is applied to polymerization reaction of a polypropylene material, and shows excellent catalytic performance, and the obtained polypropylene material has higher melt flow rate, good rigidity and excellent impact resistance, and can better meet the requirements of high-end plastic products.

Inventors

• CHI HUI
• ZHANG SAIJUN
• WU JIAJIA
• WU FAN
• LI SEN
• CAO YUWEI
• ZOU ENGUANG
• WANG DONG
• Fei Weiduo
• DUAN BAICHAO
• ZHI XIN
• HU SHUNHUI
• LUO MINGQIN

Assignees

• 浙江石油化工有限公司

Dates

Publication Date

20260512

Application Date

20260416

Claims (10)

1. 1. The preparation method of the compound external electron donor for preparing polypropylene is characterized by comprising the following steps of mixing a polypropylene catalyst, white oil and vaseline (5-50): (25-90): (0-100) by mass to obtain a mixture, adjusting the temperature of the mixture to 0-25 ℃, adding a silane coupling agent, and stirring for reaction; the addition amount of the silane coupling agent is 0.1-3wt% of the mass of the mixture; the structural general formula of the silane coupling agent is H 2 N-R-Si(OC 2 H 5 ) 3 or H 2 N-R2-NH-R1-Si(OC 2 H 5 ) 3 ; wherein R is selected from at least one of C 1 ~C 12 linear alkylene, phenylene-C 6 H 4 -; R1 and R2 are each independently selected from C 1 ~C 12 linear alkylene.
2. 2. The method for preparing a compound external electron donor for polypropylene according to claim 1, wherein the silane coupling agent comprises at least one of the following L1 to L6 silane coupling agents: L1 silane coupling agent with a structural formula of H 2 N-CH 2 -Si(OC 2 H 5 ) 3 ; L2 silane coupling agent with structural formula of H 2 N-(CH 2 ) 11 -Si(OC 2 H 5 ) 3 ; L3 silane coupling agent with structural formula of H 2 N-(CH 2 ) 4 -Si(OC 2 H 5 ) 3 ; l4 silane coupling agent with structural formula of H 2 N-C 6 H 4 -Si(OC 2 H 5 ) 3 ; l5 silane coupling agent with structural formula of H 2 N-(CH 2 ) 6 -NH-CH 2 -Si(OC 2 H 5 ) 3 ; l6 silane coupling agent has a structural formula of H 2 N-(CH 2 ) 2 -NH-(CH 2 ) 3 -Si(OC 2 H 5 ) 3 .
3. 3. The method for preparing a compound external electron donor for polypropylene according to claim 1, wherein the polypropylene catalyst is a ziegler-natta catalyst.
4. 4. The method for preparing the polypropylene compound external electron donor according to claim 1, wherein the mixing temperature is 10-30 ℃ and the mixing time is 1-60 min.
5. 5. The method for preparing the polypropylene compound external electron donor according to claim 1, wherein the stirring reaction is carried out at a temperature of 0-25 ℃ for 5-600 min.
6. 6. A compound external electron donor for preparing polypropylene, characterized in that it is prepared by the preparation method of the compound external electron donor for preparing polypropylene according to any one of claims 1 to 5.
7. 7. A polypropylene material, characterized in that the raw materials thereof comprise the compound external electron donor for preparing polypropylene according to claim 6.
8. 8. The polypropylene material according to claim 7, wherein the raw material of the polypropylene material further comprises other external electron donors; the other external electron donor includes at least one of diisopropyl dimethoxy silane DIPMS, dicyclopentyl dimethoxy silane DCPMS, diisobutyl dimethoxy silane DIBMS, and cyclohexyl methyl dimethoxy silane CHMMS.
9. 9. The polypropylene material according to claim 8, wherein the mass ratio of the compounded external electron donor to the other external electron donors is 1 (30-150).
10. 10. The polypropylene material according to claim 7, wherein the polypropylene material comprises homo-polypropylene and/or impact polypropylene; the homo-polypropylene is prepared by propylene homo-polymerization, and the impact polypropylene is prepared by impact copolymerization.

Description

Compound external electron donor for preparing polypropylene, preparation method thereof and polypropylene material Technical Field The invention belongs to the technical field of modified catalysts, and relates to a compound external electron donor for preparing polypropylene, a preparation method thereof and a polypropylene material. Background In the context of continuous upgrades in the automotive industry, the high-end field has placed more stringent demands on material properties. The traditional polypropylene material is difficult to meet the dual requirements of high-efficiency processing and molding and excellent mechanical properties, and the high-performance impact polypropylene has high modulus and high impact resistance while maintaining higher melt flow rate, so that the high-performance impact polypropylene material becomes one of key materials meeting the requirements of automobile weight reduction and structural safety. In polypropylene catalytic systems, the choice of external electron donor has a decisive influence on the catalyst activity, the hydrogen regulation sensitivity and the molecular weight distribution of the polymer. In the prior art, the tacticity and copolymerization performance of polypropylene are regulated and controlled by introducing specific external electron donor, which is a common means for improving the rigidity and toughness balance of the material. At present, the modification of polypropylene catalysts by using ionic liquid as an external electron donor has been studied, but the modification method using ionic liquid as an external electron donor has obvious defects in practical application. Firstly, the ionic liquid has poor compatibility with a polypropylene catalyst system, so that the modification effect is unstable, and particularly in large-scale industrial production, the catalyst activity fluctuation is large, and the consistency of the performances of a plurality of batches of products is difficult to ensure. Secondly, the synthesis cost of the ionic liquid is higher, polar groups possibly remain in the polymerization process of part of the ionic liquid, the dielectric property and the thermal stability of the polymer are affected, and the application of the ionic liquid in the fields of high-end automobile injection molding parts and the like with strict requirements on the purity and the stability of materials is limited. Therefore, development of a novel external electron donor modification technology with better compatibility with a polypropylene catalyst system, stable modification effect and controllable cost is needed to simplify the process flow, improve the copolymerization performance and polymerization activity stability of the catalyst and meet the large-scale production requirements of light-weight and high-end injection molding products of automobiles on high-performance polypropylene materials. Disclosure of Invention The invention aims to solve the problems in the prior art, and provides a compound external electron donor for preparing polypropylene based on modification of a silane coupling agent, which is prepared by carrying out compound modification on a polypropylene catalyst and a specific silane coupling agent in white oil and/or vaseline medium, wherein the compound external electron donor is applied to polymerization reaction of polypropylene, shows excellent catalytic performance, and the obtained polypropylene material has higher melt flow rate, good rigidity and excellent impact resistance and can better meet the requirements of high-end plastic products. One object of the invention is achieved by the following technical scheme: The preparation method of the compound external electron donor for preparing polypropylene comprises the following steps of mixing a polypropylene catalyst, white oil and vaseline (5-50) (25-90) (0-100) according to the mass ratio to obtain a mixture, adjusting the temperature of the mixture to 0-25 ℃, adding a silane coupling agent, and stirring for reaction; the addition amount of the silane coupling agent is 0.1-3wt% of the mass of the mixture; the structural general formula of the silane coupling agent is H 2N-R-Si(OC2H5)3 or H 2N-R2-NH-R1-Si(OC2H5)3; wherein R is selected from at least one of C 1~C12 linear alkylene, phenylene-C 6H4 -; R1 and R2 are each independently selected from C 1~C12 linear alkylene. Preferably, the silane coupling agent comprises at least one of the following L1-L6 silane coupling agents: L1 silane coupling agent with a structural formula of H 2N-CH2-Si(OC2H5)3; L2 silane coupling agent with structural formula of H 2N-(CH2)11-Si(OC2H5)3; L3 silane coupling agent with structural formula of H 2N-(CH2)4-Si(OC2H5)3; l4 silane coupling agent with structural formula of H 2N-C6H4-Si(OC2H5)3; l5 silane coupling agent with structural formula of H 2N-(CH2)6-NH-CH2-Si(OC2H5)3; l6 silane coupling agent has a structural formula of H 2N-(CH2)2-NH-(CH2)3-Si(OC2H5)3. Preferably, the polyp