Long palm fiber reinforced bio-based composite material and preparation method thereof
By coating long palm fiber particles with bio-based polyolefins, the problems of short fibers, easy pull-out, and uneven blending in plant fiber reinforced composites are solved, thereby improving the mechanical strength and impact performance of the composites.
Patent Information
- Application Number
- CN202511914235.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-18
- Publication Date
- 2026-02-24
AI Technical Summary
In existing plant fiber reinforced composite materials, the fibers are short, easily pulled out of the matrix, have low mechanical strength, and during the blending process, the plastic sinks while the fibers float and clump together, which cannot effectively enhance the performance of the composite material.
Bio-based polyolefins were used to coat long palm fiber particles. The palm fibers were treated with a surface modifier by atomized spraying to form long fiber ropes. The ropes were then coated in a twin-screw extruder and melt-kneaded in a kneader to prepare a long palm fiber reinforced bio-based composite material.
It improves the interfacial compatibility between fibers and the matrix, maintains fiber length, enhances the mechanical strength and impact performance of composite materials, and solves the problems of easy fiber pull-out and uneven blending.
Smart Images
Figure CN121554866A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of polymer composite materials technology, and more specifically, to a long palm fiber reinforced bio-based composite material and its preparation method. Background Technology
[0002] Bio-based materials are prepared using biomass as raw material through biological and chemical synthesis technologies. They have advantages such as renewable raw materials, reduced carbon emissions, and energy conservation. They hold an important strategic position in achieving the "dual carbon" goals and the circular economy. They can not only replace traditional petroleum-based materials, but also process a large amount of waste biomass such as straw and bagasse. Furthermore, they solve the problem of traditional chemical materials produced from non-renewable energy sources such as coal and oil being depleted due to fossil resources.
[0003] However, with the improvement of social development levels and the increasing awareness of energy conservation, emission reduction, environmental protection, and sustainable development, single materials can no longer meet the actual needs of high performance and lightweighting in many fields. People have begun to gradually turn their attention to the research of composite materials with excellent performance. Compared with glass fiber reinforced thermoplastic composites, plant fiber reinforced composites can not only reduce material costs and generate great economic benefits, but also alleviate environmental pressure and bring huge social benefits. Moreover, they have more diverse recycling methods, making them a very promising "green, low-carbon, and recyclable" composite material.
[0004] Currently, plant fiber reinforced composites have the following problems: First, the fiber length of polyolefin-modified plant fibers is generally less than 0.5 mm. The shorter the fiber length, the easier it is for the part to be pulled out of the matrix under stress, resulting in lower mechanical strength. Second, during the blending process of plastic and plant fibers, the plastic sinks while the plant fibers float and are prone to clumping, leading to insufficient and uneven fiber addition. Third, whether plant fibers are added laterally or directly, twin-screw extruders can damage the plant fibers, failing to achieve the purpose of enhancing the performance of the composite material.
[0005] Based on the above, it is very important to develop plant fiber reinforced bio-based composite materials that do not damage plant fibers, maintain the length of plant fibers, and do not affect the blending of raw materials. Summary of the Invention
[0006] This application aims to address at least one of the technical problems existing in the prior art.
[0007] Therefore, on the one hand, this application proposes a long palm fiber reinforced bio-based composite material, which is composed of the following components by mass percentage: Bio-based polyolefins 30-85% Bio-based polyolefin-coated long palm fiber particles 5-50% Compatibilizer 0-15% Filler content: 0-10%.
[0008] Preferably, the bio-based polyolefin-coated long palm fiber particles are prepared by the following method: blending, melting, and extruding bio-based polyolefin, flow modifier, and dispersant, while threading surface-modified palm fiber ropes into the flat extrusion die of a twin-screw extruder, then pulling them out, water cooling, pelletizing, and drying to obtain bio-based polyolefin-coated long palm fiber particles. The bio-based polyolefin coating material comprises the following mass percentages: Bio-based polyolefins 98.5-99.5% Flowability modifier 0.1-1% Dispersant 0.1-0.5%.
[0009] Preferably, the surface-modified palm fiber rope is prepared by the following method: placing palm fibers in a stainless steel tank with a double-walled heating and stirring mechanism, and spraying them with a surface modifier dissolved in an alcohol solvent to obtain surface-modified palm fibers, and twisting the surface-modified palm fibers to form a surface-modified palm fiber rope; the concentration of the surface modifier dissolved in the alcohol solvent is 5-10%.
[0010] Preferably, the palm fiber is one of coconut palm fiber and mountain palm fiber, the surface modifier is at least one of silane coupling agent and titanate coupling agent, the alcohol solvent is ethanol, and the diameter of the surface-modified palm fiber cord is 1.0-1.2 mm.
[0011] Preferably, the bio-based polyolefin is bio-based polypropylene, the flow modifier is bis-tert-butylperoxyisopropylbenzene, and the dispersant is white oil.
[0012] Preferably, the twin-screw extruder has an extrusion temperature of 170-220℃ and an extrusion speed of 80-120 r / min.
[0013] Preferably, the bio-based polyolefin-coated long palm fiber particles have a length of 15-30 mm and a long palm fiber content of 5-40%.
[0014] Preferably, the bio-based polyolefin is bio-based polyethylene, the compatibilizer is at least one of maleic anhydride-grafted polypropylene and maleic anhydride-grafted polyethylene, and the filler is at least one of palm fiber powder, straw powder, and rice husk powder.
[0015] On the other hand, this application also provides a method for preparing a bio-based composite material reinforced with long palm fiber, comprising the following steps: Step 1: Dry the required filler; Step 2: Add bio-based polyolefin, bio-based polyolefin-coated long palm fiber particles and compatibilizer to a kneader for melt kneading; Step 3: Add the dried filler from Step 1 into the kneader and continue kneading; Step 4: Press the kneaded molten material into sheets using a flat vulcanizing machine to produce bio-based composite materials or standard samples.
[0016] Preferably, the processing temperature of the kneader is 210-250℃, and the processing temperature of the flat vulcanizing machine is room temperature.
[0017] The beneficial effects of a long palm fiber reinforced bio-based composite material according to an embodiment of this application are: 1. By using an atomized spraying-heating method to treat the surface of palm fibers, the interfacial compatibility between palm fibers and bio-based polyolefin materials is enhanced, thereby improving the impact strength of palm fiber-reinforced bio-based polyolefin composites. 2. By using a simple method to coat palm fibers, the fiber particle length can reach 15-30mm, which solves the problems of long plant fibers being loose and difficult to feed into twin-screw extruders, and easy agglomeration and uneven dispersion when directly added for blending; 3. Using a kneader to melt the components greatly ensures that the length of the palm fiber remains essentially unchanged during processing, significantly improving the performance of the bio-based composite material. Attached Figure Description
[0018] To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained from these drawings without creative effort.
[0019] Figure 1 This is a simplified processing flow diagram of the bio-based composite material according to an embodiment of this application; Figure 2 This is a schematic diagram of bio-based polyolefin-coated palm fiber according to an embodiment of this application; Figure 3 This is a macroscopic photograph of bio-based polypropylene-coated palm fiber particles according to an embodiment of this application. Detailed Implementation
[0020] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, not all of them. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.
[0021] Unless otherwise specified, all materials mentioned in the following examples are commercially available.
[0022] Example 1 First, the mountain palm fiber is placed in a stainless steel tank with a double-walled heating and stirring mechanism. A 6% surface modifier is formed by dissolving a titanate coupling agent in ethanol and spraying it onto the surface to obtain surface-modified mountain palm fiber. The surface-modified mountain palm fiber is then twisted to form a surface-modified mountain palm fiber rope with a diameter of 1.2 mm. Then, 99.3% bio-based polypropylene, 0.5% di-tert-butylperoxyisopropylbenzene and 0.2% white oil are blended, melted and extruded. At the same time, surface-modified mountain palm fiber ropes are threaded into a flat extrusion die, then pulled out, water-cooled, pelletized and dried to obtain bio-based polypropylene coated long mountain palm fiber particles with a mountain palm fiber length of 20mm and a mountain palm fiber content of 40%. Finally, 82.5% bio-based polyethylene, 10% bio-based polypropylene-coated palm fiber particles, and 2.5% maleic anhydride-grafted polyethylene are added to a kneader (processing temperature 210-250℃) for melt kneading. 5% of dried palm fiber powder is added to the kneader in small amounts multiple times for further kneading. The kneaded melt is then pressed into sheets using a flat vulcanizing machine (processing temperature at room temperature) to produce bio-based composite materials or standard samples.
[0023] Example 2 The difference between this embodiment and Embodiment 1 is that: 70% bio-based polyethylene, 20% bio-based polypropylene coated with palm fiber particles, and 5% maleic anhydride grafted polyethylene.
[0024] Example 3 The difference between this embodiment and Embodiment 1 is that: 57.5% bio-based polyethylene, 30% bio-based polypropylene coated with Changshan palm fiber particles, and 7.5% maleic anhydride grafted polyethylene.
[0025] Example 4 The difference between this embodiment and Embodiment 1 is that: 45% bio-based polyethylene, 40% bio-based polypropylene coated with Changshan palm fiber particles, and 10% maleic anhydride grafted polyethylene.
[0026] Example 5 The difference between this embodiment and Embodiment 1 is that: 32.5% bio-based polyethylene, 50% bio-based polypropylene coated with Changshan palm fiber particles, and 12.5% maleic anhydride grafted polyethylene.
[0027] The bio-based composite materials prepared in Examples 1-5 above were subjected to performance tests, including: tensile properties: tested according to the test method of GB / T1447-2005; flexural properties: tested according to the test method of GB / T1449-2005; impact properties: tested according to the test method of GB / T1451-2005; the test results are shown in Table 1.
[0028] Table 1. Test results of Changshan palm fiber reinforced bio-based composite materials
[0029] As shown in Table 1, the introduction of palm fiber into bio-based PE materials increases the tensile strength and elastic modulus of the bio-composite material, while decreasing the elongation at break. This is because, with the increase of palm fiber, the high-strength, high-modulus palm fiber bears the main load through a good interface, and the palm fiber is firmly locked with the substrate, limiting the plastic deformation capacity of the substrate. The kneading method used to melt the components greatly ensures that the length of the palm fiber remains essentially unchanged before and after processing, promoting an increase in flexural strength and flexural modulus, thereby enhancing the bio-based composite material's resistance to bending. Furthermore, the impact strength of the bio-based composite material shows a trend of first increasing and then decreasing. This is because adding a small amount of long palm fiber does not affect the impact toughness of the bio-based composite material, but as the amount of long palm fiber increases, the long palm fiber inside the bio-based composite material will break and be pulled out upon impact. These processes absorb energy, thus reducing the impact strength.
[0030] Figure 1 This is a simplified processing flow diagram for bio-based composite materials.
[0031] Figure 2 This is a schematic diagram of bio-based polyolefin coating on palm fibers. The palm fiber rope has a small circular pore at the insertion end to prevent material leakage, and a larger elliptical pore at the discharge end. The high pressure of a twin-screw extruder is used to penetrate the highly fluid bio-based polyolefin coating material into the interior of the plant fiber rope, completing the coating of the plant fibers.
[0032] Figure 3 This is a macroscopic photograph of bio-based polypropylene coated palm fiber particles, with a particle length of 20mm and a palm fiber content of 40%.
[0033] The above embodiments are only used to illustrate specific implementations of the present invention and are not limited thereto. For those skilled in the art, various similar modifications and transformations can be made based on the concept of the present invention, and these modifications and transformations should all be considered within the scope of protection of the present invention.
Claims
1. A bio-based composite material reinforced with long palm fiber, characterized in that, It consists of the following components by mass percentage: Bio-based polyolefins 30-85% Bio-based polyolefin-coated long palm fiber particles 5-50% Compatibilizer 0-15% Filler content: 0-10%.
2. The long palm fiber reinforced bio-based composite material as described in claim 1, characterized in that, The bio-based polyolefin-coated long palm fiber particles are prepared by the following method: bio-based polyolefin, flow modifier and dispersant are blended, melted and extruded, while surface-modified palm fiber ropes are threaded into the flat extrusion die of a twin-screw extruder, then pulled out, water-cooled, pelletized and dried to obtain bio-based polyolefin-coated long palm fiber particles. The bio-based polyolefin coating material comprises the following mass percentages: Bio-based polyolefins 98.5-99.5% Flowability modifier 0.1-1% Dispersant 0.1-0.5%.
3. The bio-based composite material reinforced with long palm fiber as described in claim 2, characterized in that, The surface-modified palm fiber rope is prepared by the following method: palm fibers are placed in a stainless steel tank with a double-walled heating and stirring mechanism, and a surface modifier dissolved in an alcohol solvent is sprayed onto the fibers to obtain surface-modified palm fibers. The surface-modified palm fibers are then twisted to form a surface-modified palm fiber rope. The concentration of the surface modifier dissolved in the alcohol solvent is 5-10%.
4. The long palm fiber reinforced bio-based composite material as described in claim 3, characterized in that, The palm fiber is one of coconut palm fiber and mountain palm fiber, the surface modifier is at least one of silane coupling agent and titanate coupling agent, the alcohol solvent is ethanol, and the diameter of the surface-modified palm fiber cord is 1.0-1.2 mm.
5. The long palm fiber reinforced bio-based composite material as described in claim 2, characterized in that, The bio-based polyolefin is bio-based polypropylene, the flow modifier is bis-tert-butylperoxyisopropylbenzene, and the dispersant is white oil.
6. The method for preparing a long palm fiber reinforced bio-based composite material as described in claim 2, characterized in that, The twin-screw extruder has an extrusion temperature of 170-220℃ and an extrusion speed of 80-120 r / min.
7. The method for preparing a long palm fiber reinforced bio-based composite material as described in claim 2, characterized in that, The bio-based polyolefin-coated long palm fiber particles have a length of 15-30 mm and a long palm fiber content of 5-40%.
8. The long palm fiber reinforced bio-based composite material as described in claim 1, characterized in that, The bio-based polyolefin is bio-based polyethylene, the compatibilizer is at least one of maleic anhydride-grafted polypropylene and maleic anhydride-grafted polyethylene, and the filler is at least one of palm fiber powder, straw powder and rice husk powder.
9. The method for preparing a long palm fiber reinforced bio-based composite material as described in claim 1, characterized in that, Includes the following steps: Step 1: Dry the required filler; Step 2: Add bio-based polyolefin, bio-based polyolefin-coated long palm fiber particles and compatibilizer to a kneader for melt kneading; Step 3: Add the dried filler from Step 1 into the kneader and continue kneading; Step 4: Press the kneaded molten material into sheets using a flat vulcanizing machine to produce bio-based composite materials or standard samples.
10. The method for preparing a long palm fiber reinforced bio-based composite material as described in claim 9, characterized in that, The processing temperature of the kneader is 210-250℃, and the processing temperature of the flat vulcanizing machine is room temperature.