CN111688236A - Preparation method of continuous fiber-introduced dispersion type natural fiber reinforced thermoplastic resin prepreg tape - Google Patents
Preparation method of continuous fiber-introduced dispersion type natural fiber reinforced thermoplastic resin prepreg tape Download PDFInfo
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- CN111688236A CN111688236A CN202010536074.2A CN202010536074A CN111688236A CN 111688236 A CN111688236 A CN 111688236A CN 202010536074 A CN202010536074 A CN 202010536074A CN 111688236 A CN111688236 A CN 111688236A
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- Prior art keywords
- fiber
- thermoplastic resin
- prepreg tape
- continuous
- reinforced thermoplastic
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C70/00—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts
- B29C70/04—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts comprising reinforcements only, e.g. self-reinforcing plastics
- B29C70/28—Shaping operations therefor
- B29C70/30—Shaping by lay-up, i.e. applying fibres, tape or broadsheet on a mould, former or core; Shaping by spray-up, i.e. spraying of fibres on a mould, former or core
- B29C70/34—Shaping by lay-up, i.e. applying fibres, tape or broadsheet on a mould, former or core; Shaping by spray-up, i.e. spraying of fibres on a mould, former or core and shaping or impregnating by compression, i.e. combined with compressing after the lay-up operation
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C70/00—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts
- B29C70/04—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts comprising reinforcements only, e.g. self-reinforcing plastics
- B29C70/28—Shaping operations therefor
- B29C70/40—Shaping or impregnating by compression not applied
- B29C70/50—Shaping or impregnating by compression not applied for producing articles of indefinite length, e.g. prepregs, sheet moulding compounds [SMC] or cross moulding compounds [XMC]
- B29C70/52—Pultrusion, i.e. forming and compressing by continuously pulling through a die
- B29C70/523—Pultrusion, i.e. forming and compressing by continuously pulling through a die and impregnating the reinforcement in the die
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
- C08L23/00—Compositions of homopolymers or copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond; Compositions of derivatives of such polymers
- C08L23/02—Compositions of homopolymers or copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond; Compositions of derivatives of such polymers not modified by chemical after-treatment
- C08L23/04—Homopolymers or copolymers of ethene
- C08L23/06—Polyethene
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
- C08L2205/00—Polymer mixtures characterised by other features
- C08L2205/03—Polymer mixtures characterised by other features containing three or more polymers in a blend
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
- C08L2205/00—Polymer mixtures characterised by other features
- C08L2205/14—Polymer mixtures characterised by other features containing polymeric additives characterised by shape
- C08L2205/16—Fibres; Fibrils
Abstract
A preparation method of a dispersion type natural fiber reinforced thermoplastic resin prepreg tape introducing continuous fibers relates to a preparation method of a fiber reinforced thermoplastic resin prepreg tape. The purpose is to solve the problem that the natural fiber reinforced thermoplastic resin composite material can not realize winding forming. The method comprises the following steps: mixing natural fibers, thermoplastic polymer particles, and the like; and (4) carrying out hot pressing or extrusion molding on the material obtained in the step one. The invention utilizes natural fiber, continuous fiber and thermoplastic resin to prepare the continuous prepreg tape, solves the problem that the natural fiber reinforced thermoplastic resin composite material cannot realize winding molding, and the added continuous fiber can bear winding tension when the prepared prepreg tape is heated and wound, so that the interlayer bonding is tight. The invention is suitable for preparing the thermoplastic resin prepreg tape.
Description
Technical Field
The invention relates to a preparation method of a fiber reinforced thermoplastic resin prepreg tape.
Background
The prepreg tape used for winding and forming usually uses continuous artificial fiber as a reinforcing phase, and the resin glue solution is thermosetting resin. In order to ensure tight bonding between prepreg layers and complete unfolding of continuous fibers, tension needs to be applied to the prepreg in the winding process, and the continuous artificial fibers are the main receptors of the tension. The winding forming has the advantages of high precision, strong designability and the like, and is widely applied to the aspects of aerospace, war industry and civil products.
The natural fiber has wide source, light weight, high strength and environmental protection; the thermoplastic resin has high toughness and long storage period, can be processed for many times, and is widely applied to various fields such as transportation, decoration, garden facilities and the like by utilizing the natural fiber reinforced thermoplastic resin composite material. However, in the winding process, the thermoplastic resin needs to be heated and softened to perform interlayer adhesion, the softened thermoplastic resin cannot be stretched or fixed, and most of the natural fibers are dispersed short fibers and cannot bear the winding tension. Therefore, the natural fiber reinforced thermoplastic resin composite material cannot be wound and molded.
Disclosure of Invention
The invention provides a preparation method of a dispersion type natural fiber reinforced thermoplastic resin prepreg tape introducing continuous fibers, aiming at solving the problem that natural fiber reinforced thermoplastic resin composite materials cannot realize winding forming.
The preparation method of the dispersion type natural fiber reinforced thermoplastic resin prepreg tape with continuous fibers is carried out according to the following steps:
firstly, mixing natural fibers, thermoplastic polymer particles, a coupling agent and a lubricant;
secondly, putting the material obtained in the step one into a mold, putting continuous fibers into the mold, and performing hot press molding to obtain a pressed prepreg tape;
or putting the material obtained in the step one into an extrusion die, and penetrating one end of the continuous fiber into the extrusion die through a fiber inlet to perform co-extrusion of the thermoplastic polymer and the continuous fiber to obtain the extruded prepreg tape.
The principle and the beneficial effects of the invention are as follows:
the invention utilizes natural fiber, continuous fiber and thermoplastic resin to prepare the continuous prepreg tape, solves the problem that the natural fiber reinforced thermoplastic resin composite material cannot realize winding molding, and the added continuous fiber can bear winding tension when the prepared prepreg tape is heated and wound, so that the interlayer bonding is tight, and the performance of the obtained wound product is better.
Drawings
Fig. 1 is a schematic view of the structure of a fiber inlet on the side wall of a cavity of a coextrusion die used in example 1, in which 1 is a fiber inlet, 2 is a tapered runner, 3 is a cavity of the coextrusion die, and 4 is a continuous fiber.
The specific implementation mode is as follows:
the technical scheme of the invention is not limited to the specific embodiments listed below, and any reasonable combination of the specific embodiments is included.
The first embodiment is as follows: the preparation method of the dispersion type natural fiber reinforced thermoplastic resin prepreg tape with continuous fibers introduced according to the embodiment is carried out according to the following steps:
firstly, mixing natural fibers, thermoplastic polymer particles, a coupling agent and a lubricant;
secondly, putting the material obtained in the step one into a mold, putting continuous fibers into the mold, and performing hot press molding to obtain a pressed prepreg tape;
or putting the material obtained in the step one into an extrusion die, and penetrating one end of the continuous fiber into the extrusion die through a fiber inlet to extrude the thermoplastic polymer and the continuous fiber to obtain the extruded prepreg tape.
According to the embodiment, the continuous prepreg tape is prepared from the natural fibers, the continuous fibers and the thermoplastic resin, the problem that the natural fiber reinforced thermoplastic resin composite material cannot be wound and molded is solved, the added continuous fibers can bear winding tension when the prepared prepreg tape is heated and wound, interlayer bonding is tight, and the performance of the obtained wound product is good.
The second embodiment is as follows: the first difference between the present embodiment and the specific embodiment is: step one, the material of the thermoplastic polymer particles is polyethylene, polypropylene, polylactic acid, polyvinyl chloride, ethylene-vinyl acetate copolymer or engineering plastics.
The third concrete implementation mode: the present embodiment differs from the first or second embodiment in that: step one, the coupling agent is one or more of titanate coupling agent, isocyanate coupling agent, maleic anhydride grafted polyethylene, maleic anhydride grafted polypropylene or silane coupling agent.
The fourth concrete implementation mode: the difference between this embodiment mode and one of the first to third embodiment modes is: step one, the lubricant is one or more of stearic acid, paraffin, PE wax and the like.
The fifth concrete implementation mode: the difference between this embodiment and one of the first to fourth embodiments is: the natural fiber in the step one is one or more of wood fiber, bamboo fiber, cotton fiber, hemp fiber or straw fiber.
The sixth specific implementation mode: the difference between this embodiment and one of the first to fifth embodiments is: the length range of the natural fiber in the first step is 0.01 mm-150 mm.
The seventh embodiment: the difference between this embodiment and one of the first to sixth embodiments is: the mass ratio of the thermoplastic polymer particles to the coupling agent is 1 (0.02-0.08), and the mass ratio of the natural fibers to the thermoplastic polymer particles is (0.6-4): 1.
the specific implementation mode is eight: the present embodiment differs from one of the first to seventh embodiments in that: and step two, the hot-press molding temperature is 110-230 ℃, and the pressure is 1-10 MPa.
The specific implementation method nine: the present embodiment differs from the first to eighth embodiments in that: the temperature of the co-extrusion in the second step is 110-230 ℃.
The detailed implementation mode is ten: the present embodiment differs from one of the first to ninth embodiments in that: step two, the continuous fiber is a continuous artificial fiber or a continuous natural fiber rope; the continuous artificial fiber is carbon fiber, glass fiber, aramid fiber, nylon fiber, polyester fiber, basalt fiber, metal fiber and the like; the continuous natural fiber rope is cotton rope, hemp rope, bamboo rope or grass rope.
The following examples were used to demonstrate the beneficial effects of the present invention:
example 1:
the preparation method of the dispersion type natural fiber reinforced thermoplastic resin prepreg tape incorporating continuous fibers of this example was carried out according to the following steps:
firstly, mixing natural fibers, thermoplastic polymer particles, a coupling agent and a lubricant;
the thermoplastic polymer particles are made of polyethylene; the coupling agent is maleic anhydride grafted polyethylene; the lubricant is stearic acid; the natural fiber is wood fiber, and the length range is 0.5 mm-2 mm;
the mass ratio of the thermoplastic polymer particles to the coupling agent is 1:0.04, and the mass ratio of the natural fibers to the thermoplastic polymer particles is 1: 1;
secondly, putting the material obtained in the first step into an extrusion die, and penetrating one end of continuous fibers into the extrusion die through a fiber inlet to extrude the thermoplastic polymer and the continuous fibers, wherein the consumption of the continuous fibers is 2, so as to obtain an extruded prepreg tape;
the temperature of the coextrusion was 175 ℃;
the continuous fibers are carbon fibers.
In embodiment 1, the fiber inlet is disposed on a side wall of a cavity of a co-extrusion mold, a tapered flow channel is disposed on an inner side of the side wall of the cavity, a tapered tip of the tapered flow channel faces the inside of the cavity, a bottom end of the tapered flow channel is fixedly connected to an inner wall of the cavity, the fiber inlet is communicated with a tapered pipe, continuous fibers enter the cavity of the extrusion mold through the fiber inlet and the tapered flow channel, a mixture of natural fibers and a thermoplastic polymer is melted and mixed in the extrusion mold, a melted and mixed material is discharged from an outlet of the extrusion mold under the action of a screw extruder, and the continuous fibers are discharged together under the adhesion of the melted and mixed material, so that compounding. The tapered runner can prevent the melted and mixed materials in the cavity from flowing out from the fiber inlet in the extrusion process.
In the embodiment, the continuous prepreg tape is prepared by using the natural fibers, the continuous fibers and the thermoplastic resin, so that the problem that the natural fiber reinforced thermoplastic resin composite material cannot be wound and molded is solved, the added continuous fibers can bear the winding tension when the prepared prepreg tape is heated and wound, the interlayer bonding is tight, and the performance of the obtained wound product is good.
Winding and forming the prepreg tape prepared in the embodiment at the temperature of 170 ℃ and the tension of 2MPa to obtain a pipe, wherein the hoop tensile strength of the pipe is 85MPa, and the ring stiffness of the pipe is 15kN/m2And the mechanical property is excellent.
Example 2:
the preparation method of the dispersion type natural fiber reinforced thermoplastic resin prepreg tape incorporating continuous fibers of this example was carried out according to the following steps:
firstly, mixing natural fibers, thermoplastic polymer particles, a coupling agent and a lubricant;
the thermoplastic polymer particles are made of polypropylene; the coupling agent is maleic anhydride grafted polypropylene; the lubricant is paraffin; the natural fiber is bamboo fiber, and the length range is 10 mm-20 mm;
the mass ratio of the thermoplastic polymer particles to the coupling agent is 1:0.04, and the mass ratio of the natural fibers to the thermoplastic polymer particles is 2: 3;
secondly, putting the material obtained in the step one into a mould, putting 3 continuous fibers into the mould, and performing hot press molding to obtain a pressed prepreg tape;
the hot-press molding temperature is 185 ℃, and the pressure is 5 MPa.
The continuous fiber is aramid fiber.
This example uses natural fibers, continuous fibers and thermoplastic resin to prepare a continuous prepreg tape, and solves the problem of the prior artThe problem that the natural fiber reinforced thermoplastic resin composite material cannot realize winding forming is solved, and the prepared prepreg tape can bear winding tension when being heated and wound, so that the interlayer bonding is tight, and the performance of the obtained wound product is good. Winding and forming the prepreg tape prepared in the embodiment at the temperature of 180 ℃ and the tension of 1.5MPa to obtain a pipe, wherein the hoop tensile strength of the pipe is 95MPa, and the ring stiffness of the pipe is 17kN/m2And the mechanical property is excellent.
Claims (10)
1. A method for preparing a dispersion type natural fiber reinforced thermoplastic resin prepreg tape with continuous fibers, which is characterized by comprising the following steps: the method comprises the following steps:
firstly, mixing natural fibers, thermoplastic polymer particles, a coupling agent and a lubricant;
secondly, putting the material obtained in the step one into a mold, putting continuous fibers into the mold, and performing hot press molding to obtain a pressed prepreg tape;
or putting the material obtained in the step one into an extrusion die, penetrating one end of the continuous fiber into the extrusion die through a fiber inlet, and extruding the thermoplastic mixture and the continuous fiber to obtain the extruded prepreg tape.
2. The method for producing a dispersion type natural fiber-reinforced thermoplastic resin prepreg tape with continuous fibers according to claim 1, characterized in that: step one, the material of the thermoplastic polymer particles is polyethylene, polypropylene, polylactic acid, polyvinyl chloride, ethylene-vinyl acetate copolymer or engineering plastics.
3. The method for producing a dispersion type natural fiber-reinforced thermoplastic resin prepreg tape with continuous fibers according to claim 1, characterized in that: step one, the coupling agent is one or more of titanate coupling agent, isocyanate coupling agent, maleic anhydride grafted polyethylene, maleic anhydride grafted polypropylene or silane coupling agent.
4. The method for producing a dispersion type natural fiber-reinforced thermoplastic resin prepreg tape with continuous fibers according to claim 1, characterized in that: step one, the lubricant is one or more of stearic acid, paraffin, PE wax and the like.
5. The method for producing a dispersion type natural fiber-reinforced thermoplastic resin prepreg tape with continuous fibers according to claim 1, characterized in that: the natural fiber in the step one is one or more of wood fiber, bamboo fiber, cotton fiber, hemp fiber or straw fiber.
6. The method for producing a dispersion type natural fiber-reinforced thermoplastic resin prepreg tape with continuous fibers according to claim 1, characterized in that: the length range of the natural fiber in the first step is 0.01 mm-150 mm.
7. The method for producing a dispersion type natural fiber-reinforced thermoplastic resin prepreg tape with continuous fibers according to claim 1, characterized in that: the mass ratio of the thermoplastic polymer particles to the coupling agent is 1 (0.02-0.08), and the mass ratio of the natural fibers to the thermoplastic polymer particles is (0.6-4): 1.
8. the method for producing a dispersion type natural fiber-reinforced thermoplastic resin prepreg tape with continuous fibers according to claim 1, characterized in that: and step two, the hot-press molding temperature is 110-230 ℃, and the pressure is 1-10 MPa.
9. The method for producing a dispersion type natural fiber-reinforced thermoplastic resin prepreg tape with continuous fibers according to claim 1, characterized in that: the temperature of the extrusion in the second step is 110-230 ℃.
10. The method for producing a dispersion type natural fiber-reinforced thermoplastic resin prepreg tape with continuous fibers according to claim 1, characterized in that: step two, the continuous fiber is a continuous artificial fiber or a continuous natural fiber rope; the continuous artificial fiber is carbon fiber, glass fiber, aramid fiber, nylon fiber, polyester fiber, basalt fiber, metal fiber and the like; the continuous natural fiber rope is cotton rope, hemp rope, bamboo rope or grass rope.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010536074.2A CN111688236A (en) | 2020-06-12 | 2020-06-12 | Preparation method of continuous fiber-introduced dispersion type natural fiber reinforced thermoplastic resin prepreg tape |
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| Application Number | Priority Date | Filing Date | Title |
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| CN202010536074.2A CN111688236A (en) | 2020-06-12 | 2020-06-12 | Preparation method of continuous fiber-introduced dispersion type natural fiber reinforced thermoplastic resin prepreg tape |
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Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1688428A (en) * | 2002-10-15 | 2005-10-26 | 陶氏环球技术公司 | Articles comprising a fiber-reinforced thermoplastic polymer composition |
| US20110198016A1 (en) * | 2005-11-22 | 2011-08-18 | Kurashiki Boseki Kabushiki Kaisha | Fiber reinforced thermoplastic resin molding |
| CN108948487A (en) * | 2018-06-20 | 2018-12-07 | 东北林业大学 | A kind of long fibre or continuous fiber orientation enhancing thermoplastic polymer composite material and preparation method thereof |
| CN109676908A (en) * | 2019-01-28 | 2019-04-26 | 东北林业大学 | A kind of Wrapping formed method for preparing tubing of short fiber reinforced thermoplastic polymer |
-
2020
- 2020-06-12 CN CN202010536074.2A patent/CN111688236A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1688428A (en) * | 2002-10-15 | 2005-10-26 | 陶氏环球技术公司 | Articles comprising a fiber-reinforced thermoplastic polymer composition |
| US20110198016A1 (en) * | 2005-11-22 | 2011-08-18 | Kurashiki Boseki Kabushiki Kaisha | Fiber reinforced thermoplastic resin molding |
| CN108948487A (en) * | 2018-06-20 | 2018-12-07 | 东北林业大学 | A kind of long fibre or continuous fiber orientation enhancing thermoplastic polymer composite material and preparation method thereof |
| CN109676908A (en) * | 2019-01-28 | 2019-04-26 | 东北林业大学 | A kind of Wrapping formed method for preparing tubing of short fiber reinforced thermoplastic polymer |
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Application publication date: 20200922 |