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CN-121975169-A - Unsaturated polyester resin prepreg and preparation method thereof

CN121975169ACN 121975169 ACN121975169 ACN 121975169ACN-121975169-A

Abstract

The application discloses an unsaturated polyester resin prepreg and a preparation method thereof, and relates to the technical field of polyester resins. The unsaturated polyester resin prepreg is prepared by stirring and reacting an acid raw material and an alcohol raw material under the action of a catalyst to obtain an unsaturated polyester resin matrix, adding a crosslinking monomer, a curing agent and a coupling agent into the unsaturated polyester resin matrix, then carrying out melt stirring to obtain a resin composition, carrying out hot melt impregnation on the resin composition and reinforcing fibers to obtain impregnated fibers, and carrying out further traction, cooling shaping and cutting. The unsaturated polyester resin prepreg and the preparation method thereof get rid of the dependence of the traditional resin on a cross-linking agent, realize the tight combination of reinforcing fibers and the resin, and effectively reduce the defects of layering, debonding and the like.

Inventors

  • Liu Jinao
  • ZHANG YANHONG

Assignees

  • 威海中维新材料科技有限公司

Dates

Publication Date
20260505
Application Date
20260227

Claims (10)

  1. 1. A method for preparing an unsaturated polyester resin prepreg, comprising the steps of: S1, adding an acid raw material into an alcohol raw material, mixing, adding a catalyst, stirring under the protection of nitrogen for reaction, and cooling to obtain an unsaturated polyester resin matrix; s2, heating and melting the unsaturated polyester resin matrix, adding a crosslinking monomer, a curing agent and a coupling agent, uniformly mixing, and then regulating the viscosity to obtain a resin composition; S3, adding the resin composition into a hot-melt impregnating device, maintaining the set temperature and pressure, and continuously introducing the reinforced fibers into the hot-melt impregnating device to obtain impregnated fibers; and S4, sequentially carrying out traction, cooling shaping and cutting on the impregnated fiber to obtain the unsaturated polyester resin prepreg.
  2. 2. The method for producing an unsaturated polyester resin prepreg according to claim 1, wherein in S1, the acid-based raw material comprises any one of maleic anhydride, phthalic acid, isophthalic acid; The alcohol raw material comprises any one of pentaerythritol, ethylene glycol, propylene glycol, diethylene glycol or neopentyl glycol; The catalyst comprises any one of stannous octoate or tetrabutyl titanate; the reinforcing fiber is selected from any one of unidirectional carbon fiber, glass fiber or basalt fiber.
  3. 3. The method for producing an unsaturated polyester resin prepreg according to claim 1, wherein in S1, the mass ratio of the acid raw material, the alcohol raw material and the catalyst is (38-42): 55-60): 2-3.
  4. 4. The method for producing an unsaturated polyester resin prepreg according to claim 1, wherein in S1, the condition of the stirring reaction is 160 to 240 ℃ and the temperature is kept at 400 to 500rpm for 2 to 3 hours.
  5. 5. The method for producing an unsaturated polyester resin prepreg according to claim 1, wherein in S2, the crosslinking monomer comprises any one of diallyl phthalate, trimethylolpropane triacrylate, or dipropylene glycol diacrylate; the curing agent comprises any one of benzoyl peroxide or di-tert-butyl peroxide; the coupling agent comprises any one of gamma-aminopropyl triethoxysilane and gamma-glycidol ether oxypropyl trimethoxysilane.
  6. 6. The preparation method of the unsaturated polyester resin prepreg according to claim 1, wherein in S2, the mass ratio of the unsaturated polyester resin matrix, the crosslinking monomer, the curing agent and the coupling agent is (80-90): (5-10): (1-2): (4-8).
  7. 7. The method for producing an unsaturated polyester resin prepreg according to claim 1, wherein in S2, the melting temperature of the unsaturated polyester resin matrix is 110 to 130 ℃, and the viscosity of the resin composition after adjustment is 10000 to 15000 mPa.s; The temperature of the hot melting impregnation is 80-100 ℃, the pressure is 0.3-0.5 MPa, and the introducing rate of the reinforcing fiber is 5-10 m/min.
  8. 8. The method for producing an unsaturated polyester resin prepreg according to claim 1, wherein in S2, the mass ratio of the resin composition to the reinforcing fiber is (33 to 37): (63 to 67).
  9. 9. The method for preparing the unsaturated polyester resin prepreg according to claim 1, wherein the traction rate of the impregnated fiber is 5-10 m/min, air cooling or water cooling is adopted for cooling and shaping, and the cooling temperature is controlled at 25-40 ℃.
  10. 10. An unsaturated polyester resin prepreg prepared by the preparation method according to any one of claims 1 to 9.

Description

Unsaturated polyester resin prepreg and preparation method thereof Technical Field The application relates to the technical field of polyester resin, in particular to unsaturated polyester resin prepreg and a preparation method thereof. Background The unsaturated polyester resin prepreg has the advantages of light weight, high strength, corrosion resistance and the like, and is widely applied to the field of polyester resins. In the traditional preparation process, the unsaturated polyester resin can be cured and molded only by depending on a large amount of cross-linking agents, and the excessive cross-linking agents can cause the defects of low resin viscosity, insufficient interfacial binding force with the reinforced fibers, easy occurrence of layering, debonding and the like, and seriously influence the mechanical properties and the service life of the prepreg. Meanwhile, most of traditional resin matrix molecular chains are of linear structures, the crosslinking activity is limited, and the compactness of a network structure formed after curing is insufficient, so that the strength improvement of the prepreg is further restricted. In addition, the problems of poor interfacial compatibility of the resin and the reinforcing fiber, uneven resin distribution in the impregnation process and the like also lead to poor performance stability of the existing prepreg product, and are difficult to meet the severe requirements of high-end equipment on the comprehensive performance of the material. Therefore, development of an unsaturated polyester resin prepreg which does not need to rely on a large amount of crosslinking agents, is compact in interface combination and has excellent mechanical properties and a preparation method thereof become a technical problem to be solved urgently in the industry. Disclosure of Invention The invention aims to overcome the defects of the prior art, provides an unsaturated polyester resin prepreg and a preparation method thereof, solves the problems of uncontrolled viscosity, poor interface bonding, insufficient mechanical property and the like caused by the dependence of a large amount of cross-linking agents of the traditional prepreg through the optimization of a raw material system and the collaborative design of a process, and realizes the high strength, low defect rate and good molding stability of the prepreg. In order to achieve the above purpose, the invention adopts the following technical scheme: in a first aspect, the present application provides a method for preparing an unsaturated polyester resin prepreg, comprising the steps of: S1, adding an acid raw material into an alcohol raw material, mixing, adding a catalyst, stirring under the protection of nitrogen for reaction, and cooling to obtain an unsaturated polyester resin matrix; s2, heating and melting the unsaturated polyester resin matrix, adding a crosslinking monomer, a curing agent and a coupling agent, uniformly mixing, and then regulating the viscosity to obtain a resin composition; S3, adding the resin composition into a hot-melt impregnating device, maintaining the set temperature and pressure, and continuously introducing the reinforced fibers into the hot-melt impregnating device to obtain impregnated fibers; and S4, sequentially carrying out traction, cooling shaping and cutting on the impregnated fiber to obtain the unsaturated polyester resin prepreg. Further, the acid raw material comprises any one of maleic anhydride, phthalic acid and isophthalic acid; The alcohol raw material comprises any one of pentaerythritol, ethylene glycol, propylene glycol, diethylene glycol or neopentyl glycol; The catalyst comprises any one of stannous octoate or tetrabutyl titanate; The reinforcing fiber is selected from any one of unidirectional carbon fiber, glass fiber or basalt fiber. In an unsaturated polyester resin matrix, phthalic acid, isophthalic acid and maleic anhydride are used as basic raw materials of acids, and alcohol raw materials such as ethylene glycol and propylene glycol are matched at the same time, after the raw materials are mixed according to a specific proportion, a corresponding catalyst is added, and then dehydration copolycondensation reaction is carried out in a high-temperature environment of 160-240 ℃. The carboxyl in the acid raw material molecule and the hydroxyl in the alcohol raw material molecule are subjected to esterification reaction, one molecule of water is removed every time one ester bond is generated, more and more acid molecules and alcohol molecules are connected with each other through ester bonds along with the continuous progress of the reaction, and finally the semitransparent solid resin matrix with high molecular weight and high softening point is obtained. In the process, pentaerythritol contains a plurality of hydroxyl groups, and when the pentaerythritol participates in copolycondensation reaction, the hydroxyl groups are combined with different acid molecules