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CN-121991308-A - SEBS special material for toughening polypropylene, preparation method and application thereof

CN121991308ACN 121991308 ACN121991308 ACN 121991308ACN-121991308-A

Abstract

The invention relates to a special SEBS material for toughening polypropylene, which comprises styrene and butadiene, wherein the molecular weight of the special SEBS material is 8.9-11.3X10 4 , the mass content of a styrene chain segment is 13-50%, and the mass content of a1, 2 structure chain segment of butadiene is 20-65%. The invention realizes that the room temperature impact strength and the low temperature impact strength of the PP are effectively improved and simultaneously has lower room temperature shrinkage rate by specially designing the SEBS structure, can realize excellent balance of high rigidity and high toughness of the PP by only needing a small amount of special SEBS material when the invention is used for toughening the polypropylene, can effectively improve the toughness of homo-polypropylene resin and co-polypropylene resin, can keep higher rigidity, and has the advantages of simple and efficient preparation method, simple process flow and relatively lower cost.

Inventors

  • LI WEIJIE
  • JIANG XIANGBAO
  • ZHAO SHUAI
  • LIU DONG
  • JIN YONGHUI
  • Niu Changtai
  • HUANG JIAJIE
  • Ge Jiejie

Assignees

  • 浙江众立合成材料科技股份有限公司

Dates

Publication Date
20260508
Application Date
20251219

Claims (10)

  1. 1. A special SEBS material for toughening polypropylene is characterized in that the preparation monomer of the special SEBS material comprises styrene and butadiene, the molecular weight of the special SEBS material is 8.9-11.3X10 4 , the mass content of a styrene chain segment in the special SEBS material is 13-50%, and the mass content of a 1,2 structure chain segment of butadiene is 20-65%.
  2. 2. The SEBS special material for toughening polypropylene according to claim 1, wherein the mass content of a styrene chain segment is 13-20%, the mass content of a 1,2 structure chain segment of butadiene is 38-50%, and the mass content of a styrene-butadiene diblock copolymer is 40-50%.
  3. 3. A method for preparing the special material for toughening the SEBS by using the polypropylene according to claim 1, which is characterized by comprising the following steps: (1) The synthesis of SBS glue solution comprises the steps of firstly adding a solvent into a reaction kettle protected by nitrogen, heating, adding styrene and an initiator to start polymerization reaction, after 20-40 min of reaction, adding a polarity regulator and butadiene to perform two-stage reaction, then adding a coupling agent to continue the reaction, and obtaining the SBS glue solution after polymerization is finished; (2) And (3) hydrogenation of the SBS glue solution, namely, carrying out selective catalytic hydrogenation on the SBS glue solution obtained in the step (1), and controlling the hydrogenation degree to be more than 99.5% to obtain the SEBS special material.
  4. 4. The preparation method of the SEBS special material for toughening the polypropylene, which is disclosed in claim 3, is characterized in that in the step (1), the reaction temperature is 50-70 ℃, the reaction time is 0.5-3 hours, the polarity regulator is one or more of tetramethyl ethylenediamine, diethylene glycol dimethyl ether, tetrahydrofuran and 1, 2-dichlorobenzene, and the initiator is an alkyl lithium initiator.
  5. 5. The preparation method of the SEBS special material for toughening the polypropylene, which is disclosed in claim 3, is characterized in that in the step (2), the hydrogenation reaction time is 1.5-2.5 h, and the catalyst adopted in the hydrogenation reaction is dichloro titanocene and an organosilicon compound.
  6. 6. The application of the SEBS special material as claimed in claim 1, wherein the SEBS special material is used for blending, toughening and modifying with polypropylene resin.
  7. 7. The use according to claim 6, characterized by the steps of: (i) Binary blending is carried out on SEBS special material and polypropylene resin; (ii) Adding inorganic filler, extruding, granulating and injection moulding.
  8. 8. The application of the composition of claim 6, wherein the SEBS special material is 5-15 parts by weight and the polypropylene resin is 85-95 parts by weight.
  9. 9. The method according to claim 7, wherein the amount of the SEBS special material is 10-15 parts by weight, the amount of the polypropylene resin is 60-70 parts by weight, and the amount of the inorganic filler is 20-25 parts by weight.
  10. 10. The method according to claim 9, wherein the inorganic filler is one of talc, mica powder or glass fiber.

Description

SEBS special material for toughening polypropylene, preparation method and application thereof Technical Field The invention belongs to the technical field of high polymer material polymerization and modification, and particularly relates to a special SEBS material for toughening polypropylene, a preparation method and application thereof. Background Polypropylene (PP) is the most widely used plastic in the automotive industry, and is developed from a cheap general plastic into a high-performance material capable of meeting various demanding requirements of automobiles through performance customization by virtue of a mature modification technology under the driving of urgent demands of the automotive industry for light weight, low cost and functional integration. Currently, the demand for PP by automobiles has exceeded basic mechanical properties, turning to higher performance and functionalization. Along with the popularization of plastic steel, polypropylene is increasingly widely applied to inner and outer decorative parts of automobiles, and the polypropylene has higher requirements on the material performance. However, the linear molecular structure of the common polypropylene has the obvious defects that the high strength and the high rigidity are endowed, the molding shrinkage rate is large due to the higher crystallinity, the dimensional stability is challenging to be outstanding, and meanwhile, the glass transition temperature is about-10 ℃, so that the toughness of the material is suddenly reduced and the brittleness is obviously increased in a low-temperature environment. In order to solve the problems, the main technical route is to blend an elastomer, an inorganic filler and polypropylene, and improve the toughness of the polypropylene through compound modification. Chinese patent CN 103146060A discloses a polypropylene composite material reinforced and toughened by nano particles and elastomer and a preparation method thereof, and Ethylene Propylene Diene Monomer (EPDM) can better toughen PP, but most of commercial materials are blocky, are difficult to uniformly mix with PP granules, and are compatibilized by adding a third component copolymer, and meanwhile, the processing process is complicated. However, the toughness of the PP is effectively improved by toughening the PP with the ethylene-octene copolymer (POE), but the rigidity and the dimensional stability of the PP are seriously reduced. Among the numerous elastomers, SEBS, prepared by anionic polymerization, is a key toughening agent for modified polypropylene. The molecular structure of SEBS is composed of a hard styrene segment with a glass transition temperature of about 100 ℃ and a soft ethylene-butene segment with a glass transition temperature of about-60 ℃, which is characterized by high elasticity in the range of-60 ℃ to 100 ℃. The current main stream SEBS product in the market is a triblock copolymer of linear styrene-butadiene, the mass content of a styrene chain segment is about 30%, and the structural advantage of the triblock copolymer in a composite system is difficult to embody. How to effectively regulate the molecular structure of SEBS, and accurately develop a special toughening material for improving low-temperature brittleness and high shrinkage of polypropylene are technical problems to be solved by scientific researchers. Disclosure of Invention In order to solve the technical problems of high low-temperature brittleness, high shrinkage, rigidity and toughness balance and the like of polypropylene in the prior art, the invention provides a special SEBS material for toughening polypropylene, a preparation method and application thereof, and the special SEBS material for toughening polypropylene is designed based on the controllable preparation advantage of an anionic polymerization method, and a polypropylene composite material with excellent impact resistance and lower shrinkage is prepared through the design and optimization of a formula. In order to achieve the aim of the invention, the invention adopts the following technical scheme: The preparation monomer of the SEBS special material comprises styrene and butadiene, wherein the molecular weight of the SEBS special material is 8.9-11.3X10 4, the mass content of a styrene chain segment is 13-50%, and the mass content of a1, 2 structure chain segment of butadiene is 20-65%. Preferably, the mass content of the styrene chain segment is 13-20%, the mass content of the 1,2 structure chain segment of butadiene is 38-50%, and the mass content of the styrene-butadiene diblock copolymer is 40-50%. The SEBS special material mainly comprises a styrene-butadiene triblock copolymer (PS-PB-PS) and a styrene-butadiene diblock copolymer (PS-PB), wherein the structural formula of the styrene-butadiene triblock copolymer is shown as a formula (I), and the structural formula of the styrene-butadiene diblock copolymer is shown as a formula (II): (I) (II) In the above formula (I) a