Bow hair composite material as well as preparation method and application thereof

Abstract

The invention belongs to the technical field of bow hair materials, and particularly relates to a bow hair composite material and a preparation method and application thereof. The bow hair composite material comprises a base material, and filler and rosin powder which are dispersed in the base material, the base material is polyamide; and the filler is corundum powder. According to the bow hair composite material, the rosin powder, the specific type of base materials and the filler are adopted and have a synergistic effect, and the surface treatment process is combined, so that the bow hair composite material has good friction performance, wear resistance and mechanical performance.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of bow hair materials, and particularly relates to a bow hair composite material and a preparation method and application thereof. BACKGROUND

[0002] Traditional violin bow hairs mainly adopt natural horse tail hairs. The natural horse tail hairs have a natural scale-like structure on the surface, and can provide necessary friction after being matched with rosin powder. However, the following problems still exist: the source of the natural horse tail hairs is limited, the price is high, and the quality is unstable; the wear resistance is poor, and the bow hairs are prone to wear and break after long-time use, and the service life is short; the friction force decays obviously, the friction performance is unstable, and the rosin needs to be frequently applied to maintain the sound effect, thereby increasing the use and maintenance burden; and the environmental adaptability is poor, and factors such as humidity and temperature can significantly affect the performance, thereby causing the tone to fluctuate.

[0003] At present, researchers attempt to replace the natural bow hairs with polymer fibers. However, the polymer fibers are difficult to keep the rosin attached due to the smooth surface of the polymer fibers, the friction performance is insufficient, and the sound quality is poor. On the other hand, the conventional polymer fibers have technical bottlenecks in terms of friction, flexibility and wear resistance, and the surface structure lacks targeted regulation.

[0004] Therefore, it is of great significance to provide a bow hair composite material with good friction performance, wear resistance and mechanical properties. SUMMARY

[0005] The present application aims to solve one or more of the technical problems existing in the prior art, and at least provide a beneficial choice. Specifically, the present application provides a bow hair composite material with good friction performance, wear resistance and mechanical properties.

[0006] The inventive concept of the present application: the bow hair composite material of the present application comprises a substrate, and fillers and rosin powder dispersed in the substrate; the substrate is polyamide; and the fillers are corundum powder. The bow hair composite material has good friction performance, wear resistance and mechanical properties, and the friction performance is stable by using the specific types of substrate, fillers and rosin powder in combination.

[0007] Therefore, the first aspect of the present application provides a bow hair composite material.

[0008] Specifically, the bow hair composite material comprises a substrate, and fillers and rosin powder dispersed in the substrate; the substrate is polyamide; the fillers are corundum powder.

[0009] Preferably, in the bow hair composite material, the mass percentage of the filler is 4.5-17%; more preferably, the mass percentage of the filler is 5-15%; and even more preferably, the mass percentage of the filler is 10%.

[0010] Preferably, the rosin powder in the bow hair composite material has a mass percentage of 1.8-11%; more preferably, the rosin powder has a mass percentage of 2-10%; and even more preferably, the rosin powder has a mass percentage of 5%.

[0011] Preferably, the bow hair composite material, by mass percentage, consists of 4.5-17% filler, 1.8-11% rosin powder, and the balance being a base material.

[0012] More preferably, the bow hair composite material, by mass percentage, consists of 5-15% filler, 2-10% rosin powder, and the balance being a base material.

[0013] More preferably, the bow hair composite material, by mass percentage, consists of 10% filler, 5% rosin powder, and the remainder being a base material.

[0014] Preferably, the ratio of the mass of the substrate to the sum of the masses of the filler and rosin powder is (2-11):1; more preferably, the ratio of the mass of the substrate to the sum of the masses of the filler and rosin powder is (2-10):1.

[0015] Preferably, the corundum powder has a mesh size of 700-900 mesh; more preferably, the corundum powder has a mesh size of 750-850 mesh; and even more preferably, the corundum powder has a mesh size of 800 mesh.

[0016] Preferably, the friction coefficient of the bow hair composite material is 0.34-0.40; more preferably, the friction coefficient of the bow hair composite material is 0.37.

[0017] Preferably, the surface roughness of the bow hair composite material is 0.80-0.90 μm; more preferably, the surface roughness of the bow hair composite material is 0.85 μm.

[0018] A second aspect of the present invention provides a method for preparing the bow hair composite material described in the first aspect of the present invention.

[0019] Specifically, the preparation method of the bow hair composite material includes the following steps: (1) The substrate, filler and rosin powder are mixed and melt-spun to obtain bow hair fibers; (2) The bow hair fibers are subjected to chemical surface treatment and physical surface treatment to obtain the bow hair composite material.

[0020] Preferably, in step (1), the mixing process further includes melt mixing using an extruder.

[0021] Preferably, the extruder is a twin-screw extruder.

[0022] Preferably, the temperature of the melt mixing is 240-280°C; more preferably, the temperature of the melt mixing is 250-270°C.

[0023] Preferably, the melt mixing time is 2-10 minutes; more preferably, the melt mixing time is 3-6 minutes.

[0024] Preferably, the screw speed of the twin-screw extruder is 50-150 rpm, and more preferably, the screw speed of the twin-screw extruder is 80-120 rpm.

[0025] Preferably, in step (1), the temperature of the melt spinning is 250-285°C; more preferably, the temperature of the melt spinning is 260-275°C.

[0026] Preferably, in step (1), the diameter of the bow hair fiber is 110-220 μm; more preferably, the diameter of the bow hair fiber is 120-200 μm.

[0027] Preferably, in step (2), the chemical surface treatment includes any one of oxidation treatment, acid treatment, and swelling treatment.

[0028] Preferably, when the chemical surface treatment includes an oxidation treatment, the reagent used in the oxidation treatment includes at least one of hydrogen peroxide and potassium permanganate.

[0029] Preferably, the hydrogen peroxide exists in the form of an aqueous solution, i.e., an aqueous solution of hydrogen peroxide; the potassium permanganate exists in the form of an aqueous solution, i.e., an aqueous solution of potassium permanganate.

[0030] Preferably, when using an aqueous hydrogen peroxide solution, the volume fraction of the aqueous hydrogen peroxide solution is 5.5-7.5%, more preferably, the volume fraction of the aqueous hydrogen peroxide solution is 6.0-7.0%, and even more preferably, the volume fraction of the aqueous hydrogen peroxide solution is 6.5%.

[0031] Preferably, when using an aqueous hydrogen peroxide solution, the chemical surface treatment method is immersion, that is, immersing the bow hair fibers in an aqueous hydrogen peroxide solution.

[0032] Preferably, when using an aqueous hydrogen peroxide solution, the soaking time is 12-30 hours; more preferably, the soaking time is 16-24 hours; even more preferably, the soaking time is 20 hours. Preferably, when using an aqueous potassium permanganate solution, the volume fraction of the potassium permanganate solution is 8-12%; more preferably, the volume fraction of the potassium permanganate solution is 9-11%; even more preferably, the volume fraction of the potassium permanganate solution is 10%.

[0033] Preferably, when using an aqueous solution of potassium permanganate, the chemical surface treatment method is immersion, that is, immersing the bow hair fibers in an aqueous solution of potassium permanganate.

[0034] Preferably, when using an aqueous solution of potassium permanganate, the soaking time is 1-24 hours; more preferably, the soaking time is 8-24 hours; and even more preferably, the soaking time is 24 hours.

[0035] Preferably, when the chemical surface treatment includes acid treatment, the reagent used in the acid treatment includes formic acid.

[0036] Specifically, the formic acid exists in the form of an aqueous solution, namely, an aqueous formic acid solution.

[0037] Preferably, the volume fraction of the formic acid aqueous solution is 8-12%, more preferably, the volume fraction of the formic acid aqueous solution is 9-11%; and even more preferably, the volume fraction of the formic acid aqueous solution is 10%.

[0038] Preferably, when using an aqueous formic acid solution, the chemical surface treatment method is immersion, that is, immersing the bow hair fibers in an aqueous formic acid solution.

[0039] Preferably, when using an aqueous formic acid solution, the soaking time is 12-30 hours; more preferably, the soaking time is 16-24 hours; and even more preferably, the soaking time is 24 hours.

[0040] Preferably, when the chemical surface treatment includes a swelling treatment, the reagent used in the swelling treatment includes dimethylformamide (DMF).

[0041] Specifically, the dimethylformamide exists in the form of an aqueous solution, namely, an aqueous solution of dimethylformamide.

[0042] Preferably, the volume fraction of the dimethylformamide aqueous solution is 8-12%; more preferably, the volume fraction of the dimethylformamide aqueous solution is 9-11%; and even more preferably, the volume fraction of the dimethylformamide aqueous solution is 10%.

[0043] Preferably, when using an aqueous solution of dimethylformamide, the chemical surface treatment method is immersion, that is, immersing the bow hair fibers in an aqueous solution of dimethylformamide.

[0044] Preferably, when using an aqueous solution of dimethylformamide, the soaking time is 12-30 hours; more preferably, the soaking time is 16-24 hours; and even more preferably, the soaking time is 24 hours.

[0045] Specifically, this invention employs different reagents for chemical surface treatment, which can specifically improve the surface activity and microstructure of the bow hair fibers. For example, hydrogen peroxide can introduce active groups through oxidation, adjusting the roughness of the bow hair fibers. This is because the active groups introduced by hydrogen peroxide treatment are not stable peroxide bonds (peroxide bonds are very unstable and easily decompose). The hydroxyl radicals generated by the decomposition of hydrogen peroxide have extremely strong oxidizing properties and can react with the surface of polyamide molecular chains, causing some amide groups to break and undergo further oxidation. This ultimately forms polar groups such as hydroxyl (-OH) and carbonyl (-C=O) on the fiber surface. These groups increase the surface energy and polarity of the bow hair fibers, forming chemical anchors that allow rosin powder to "embed" or adhere more firmly to the surface of the bow hair fibers, making the rosin powder easier to bind and thus enhancing the frictional properties.

[0046] For example, potassium permanganate can be used to control the degree of oxidation in stages, adjusting the roughness of the bow hair fibers. This is because potassium permanganate treatment allows for staged control of the oxidation depth by adjusting the treatment time and concentration. Light oxidation maintains higher strength, while heavy oxidation increases roughness and friction. This staged control not only expands the range of material performance adjustments but also enhances the wear resistance and application adaptability of the bow hair. For instance, formic acid can adjust the roughness of the bow hair fibers through acid etching; DMF can optimize surface flexibility through swelling.

[0047] Preferably, the physical surface treatment includes mechanical grinding; more preferably, the mechanical grinding is micro-nano scale mechanical grinding.

[0048] Preferably, mechanical grinding is performed using a grinding wheel with a grit size of 1800-2200 mesh and a rotation speed of 180-220 rpm; more preferably, the grit size of the grinding wheel is 1900-2100 mesh and the rotation speed is 190-210 rpm; even more preferably, the grit size of the grinding wheel is 2000 mesh and the rotation speed is 200 rpm.

[0049] Preferably, the mechanical grinding time is 1-3 minutes to obtain a uniform roughness on the fiber surface.

[0050] Specifically, surface optimization using micro-nano scale mechanical grinding technology can form a uniform micro-rough structure.

[0051] Specifically, the bow hair fibers undergo stepwise surface treatment, namely chemical surface treatment and physical surface treatment, to form a uniform and stable micro-rough structure on the surface of the bow hair fibers. This structure can significantly increase the coefficient of friction, thereby significantly improving the frictional performance and wear resistance of the material. At the same time, it can also reduce rosin consumption and stabilize the tone.

[0052] A third aspect of the present invention provides a musical instrument.

[0053] Specifically, the musical instrument includes the bow hair composite material described in the first aspect of the present invention.

[0054] Preferably, the musical instrument includes a stringed instrument.

[0055] Preferably, the stringed instrument includes any one of a violin, viola, and cello.

[0056] Compared with the prior art, the beneficial effects of the technical solution provided by the present invention are as follows: (1) The present invention uses rosin powder, a specific type of substrate and filler, which work together and are combined with surface treatment process to make the bow hair composite material have good friction performance, wear resistance and mechanical properties; and the friction performance is stable, with good environmental adaptability and durability. Compared with natural horsehair, the service life is increased by more than 2 times.

[0057] (2) The present invention can adjust the parameters in the step-by-step surface treatment process according to the performance requirements (such as gentle friction for classical music and strong friction for modern music) to achieve customization.

[0058] (3) The preparation process of this invention is simple, the raw materials are readily available, the production process can be carried out continuously on an industrial scale, and the cost is low, only 1 / 3 to 1 / 2 of that of natural horsehair. In addition, the surface treatment of this invention is carried out at room temperature and pressure, the concentration of the treatment agent is low, and the final product has no harmful residues, which meets environmental protection requirements. Attached Figure Description

[0059] Figure 1 This is a scanning electron microscope image of natural horsehair from Comparative Example 3 of the present invention. Figure 2 This is a scanning electron microscope image of the bow hair composite material of Example 1 of the present invention; Figure 3 This is a scanning electron microscope image of the bow hair composite material of Example 2 of the present invention; Figure 4 This is a scanning electron microscope image of the bow hair composite material of Example 3 of the present invention; Figure 5 This is the energy dispersive spectroscopy (EDS) analysis diagram of the bow hair composite material in Example 1 of the present invention; Figure 6 This is the elemental analysis mapping diagram of the bow hair composite material in Example 1 of the present invention; Figure 7 The mechanical properties of the bow hair composite materials in Examples 1-4 and Comparative Examples 1-6 of this invention are shown in the diagram. Detailed Implementation

[0060] To enable those skilled in the art to more clearly understand the technical solutions described in this invention, the following embodiments are provided for illustration. It should be noted that the following embodiments do not constitute a limitation on the scope of protection claimed by this invention.

[0061] Unless otherwise specified, the raw materials, reagents or devices used in the following examples are available from conventional commercial sources or can be obtained by existing known methods.

[0062] Example 1 This embodiment provides a bow hair composite material, which is prepared by using polyamide 66 (PA66), 800-mesh corundum powder and rosin powder in a mass ratio of 85:10:5, namely 85g of PA66, 10g of 800-mesh corundum powder and 5g of rosin powder.

[0063] This embodiment also provides a method for preparing the above-mentioned bow hair composite material, the steps of which are as follows: (1) Raw material mixing: PA66, corundum powder and rosin powder are mixed evenly and melt-mixed using a twin-screw extruder. The melt-mixing temperature is 260℃ and the melt-mixing time is 5min. The screw speed of the twin-screw extruder is 100rpm to obtain the mixture. (2) Preparation of bow hair fibers: At a temperature of 270℃, the mixture obtained in step (1) is melt-spun to prepare bow hair fibers with a diameter of 120-200μm, and then cooled and solidified in air; (3) Surface treatment: The bow hair fiber is placed in a 10% potassium permanganate aqueous solution and soaked at room temperature for 24 hours. After taking it out, it is rinsed with deionized water and air-dried. Then, the surface of the bow hair fiber is micro-nano mechanically ground with a grinding wheel with a particle size of 2000 mesh, a grinding speed of 200 rpm, and a grinding time of 2 min, so that a uniform and fine protrusion is formed on its surface to obtain the bow hair composite material.

[0064] Example 2 The only difference between Example 2 and Example 1 is that Example 2 uses an aqueous solution of hydrogen peroxide for chemical surface treatment. Specifically, 500 mL of a 6.5% hydrogen peroxide aqueous solution is used and the solution is left to stand at room temperature for 20 hours for chemical surface treatment. The rest is the same as in Example 1.

[0065] Example 3 The only difference between Example 3 and Example 1 is that Example 3 uses a dimethylformamide aqueous solution for chemical surface treatment. Specifically, 500 mL of a 10% dimethylformamide aqueous solution is used and the surface is left to stand at room temperature for 24 hours for chemical surface treatment. The rest is the same as in Example 1.

[0066] Example 4 The only difference between Example 4 and Example 1 is that Example 4 uses an aqueous formic acid solution for chemical surface treatment. Specifically, 500 mL of a 10% formic acid aqueous solution is used and the surface is left to stand at room temperature for 24 hours for chemical surface treatment. The rest is the same as in Example 1.

[0067] Comparative Example 1 The only difference between Comparative Example 1 and Example 1 is that Comparative Example 1 uses 2g of wollastonite to replace the corundum powder in equal amounts. That is, the mass of each raw material in Comparative Example 1 is 85g of PA66, 8g of 800-mesh corundum powder, 2g of wollastonite, and 5g of rosin powder, respectively. The rest is the same as in Example 1.

[0068] Comparative Example 2 The only difference between Comparative Example 2 and Example 1 is that Comparative Example 2 does not undergo any chemical surface treatment and is directly subjected to micro-nano mechanical grinding; otherwise, it is the same as Example 1.

[0069] Comparative Example 3 Comparative Example 3 used commercial natural horsehair as a control sample and was directly subjected to subsequent performance tests without any chemical or physical surface treatment.

[0070] Comparative Example 4 The only difference between Comparative Example 4 and Example 1 is that Comparative Example 4 uses ethylene-vinyl acetate copolymer (EVA) to replace PA66 in Example 1 in an equal amount; otherwise, it is the same as Example 1.

[0071] Comparative Example 5 The only difference between Comparative Example 5 and Example 1 is that Comparative Example 5 uses PA66 to replace the rosin powder in Example 1 in an equal amount, that is, no rosin powder is added, otherwise it is the same as Example 1.

[0072] Comparative Example 6 The only difference between Comparative Example 6 and Example 1 is that Comparative Example 6 uses wollastonite to replace the corundum powder in Example 1 in an equal amount, that is, no corundum powder is added, while the rest is the same as Example 1.

[0073] Performance testing 1. Scanning electron microscopy observation Scanning electron microscopy (SEM) was performed on the natural horsehair in Comparative Example 3. The SEM images are shown below. Figure 1 As shown. Among them, Figure 1Figures (a), (b), (c), and (d) are scanning electron microscope images of natural horsehair at different magnifications, and figures (c) and (d) are scanning electron microscope images of natural horsehair at different locations.

[0074] Depend on Figure 1 It can be seen that the surface of natural horsehair exhibits significant inhomogeneity, including a scaly structure and variations in roughness. This inhomogeneity causes fluctuations in friction when the bow hair contacts the strings, resulting in poor sound stability. Simultaneously, this inhomogeneity leads to stress concentration on the bow hair surface, resulting in insufficient wear resistance and consequently a shorter lifespan. Furthermore, the porous structure of the bow hair surface increases moisture adsorption, causing frictional properties to fluctuate with ambient humidity, further affecting performance.

[0075] The bow hair composite material prepared in Example 1 was observed by scanning electron microscopy. The scanning electron microscopy image is shown below. Figure 2 As shown. Figure 2 Figures (a) and (b) are scanning electron microscope images of the bow hair composite material of Example 1 at different magnifications.

[0076] Depend on Figure 2 It can be seen that after treatment with potassium permanganate aqueous solution, the roughness of the bow hair composite material increases, and the originally relatively smooth fiber surface develops micron / nano-scale pits, grooves, and protrusions. Figure 2 Figure (b) shows that there are deposit traces on the bow hair surface, such as bright spots or granular deposits; microcracks or delamination areas are present on the bow hair surface, because when the processing time is long (>12h), local cracking or flake peeling may occur on the surface. In addition, the diameter of the bow hair composite material was measured to be approximately 198.7μm.

[0077] The bow hair composite material prepared in Example 2 was observed by scanning electron microscopy. The scanning electron microscopy image is shown below. Figure 3 As shown.

[0078] Depend on Figure 3 It can be seen that the bow hair composite material treated with hydrogen peroxide aqueous solution exhibits slight roughening, slight particle exposure, a cleaner surface, and no deposits. This indicates that hydrogen peroxide treatment is a mild surface modification method, suitable for improving tribological properties without significantly weakening the matrix strength.

[0079] The bow hair composite material prepared in Example 3 was observed by scanning electron microscopy. The scanning electron microscopy image is shown below. Figure 4 As shown. Figure 4 Figures (a) and (b) are scanning electron microscope images of the cross-section of the bow hair composite material at different magnifications; Figure 4Figures (c), (d), and (e) are scanning electron microscope images of the surface of the bow hair composite material at different magnifications.

[0080] Depend on Figure 4 As can be seen, the bowhair composite material treated with DMF aqueous solution exhibits a uniform microporous structure, protruding particles, and a wavy / wrinkled structure under scanning electron microscopy, which is due to swelling-shrinkage. Compared with oxidation treatment by hydrogen peroxide aqueous solution and potassium permanganate aqueous solution, the roughening after DMF aqueous solution treatment is more uniform and free of deposits, making it suitable for improving frictional properties while maintaining good mechanical properties. Furthermore, due to… Figure 4 As can be seen from Figure (e), the diameter of the bow hair composite material is 196.5 μm.

[0081] 2. Energy dispersive spectroscopy and elemental analysis Energy dispersive spectroscopy (EDS) and elemental analysis were performed on the bow hair composite material prepared in Example 1. The EDS results are as follows: Figure 5 As shown, the element analysis mapping diagram is as follows: Figure 6 As shown.

[0082] Depend on Figure 5 It can be seen that the sample surface is mainly composed of carbon (C) and oxygen (O) elements. Trace amounts of manganese (Mn) were detected in the potassium permanganate-treated sample, indicating that an oxidation reaction did occur on the surface and a small amount of reaction products adhered.

[0083] Depend on Figure 6 As can be seen, the lower left area shows a clear interplay of red and green, indicating the presence of a mixture of C and O. The upper right area is predominantly red, suggesting a relatively high carbon content and a low oxygen content. A distinct interface / boundary zone exists in the middle, with a yellowish or orange hue (red + green superposition), possibly indicating a relatively uniform coexistence of C and O. This boundary zone may represent two different materials or areas that have undergone different treatments, such as the interface of a composite material or a layer on the surface that has been oxidized. The more uniform mixing of C and O at the interface may indicate some kind of chemical reaction or surface modification (e.g., oxidation or introduction of functional groups). In other words, the elemental analysis chart further shows that carbon and oxygen are uniformly distributed on the fiber surface.

[0084] Furthermore, combined with scanning electron microscopy morphological observation, it was demonstrated that the surface treatment method of the present invention can effectively improve the structural characteristics and elemental distribution of the fiber surface, thereby enhancing frictional performance and wear resistance. Regarding elemental distribution, a uniform distribution avoids localized enrichment or deficiency of components, ensuring consistent hardness and chemical properties on the fiber surface, improving the overall stability of frictional performance, and preventing localized "slippage" or "excessive string grip" during performance. Secondly, a uniform elemental distribution helps enhance wear resistance because, during friction, the surface will not experience premature wear or micro-cracks due to localized differences in properties, thus significantly extending the lifespan of the bow hair. Thirdly, a uniform distribution of surface-active elements improves the adhesion of auxiliary materials such as rosin, making the rosin coating distribution more stable and further enhancing the frictional consistency between the bow hair and the strings.

[0085] 3. Friction coefficient and surface roughness test The friction coefficient, surface roughness, and wear resistance of the bow hair composite materials of Example 1 and Comparative Examples 1-6 were tested using the following methods: Surface roughness test: The test was conducted in accordance with ISO 4287:1997, with n=5 test samples. The average value was calculated, and the unit was μm. Friction coefficient test: The test was conducted using a fretting friction and wear tester, in accordance with ASTM G133-05 (2016). The specific conditions were: load 0.5 N, sliding speed 10 mm / s, reciprocating stroke 5 mm, number of cycles 1000, number of test samples n=5, and the average value was calculated. Abrasion resistance test: The test is conducted in accordance with ASTM G99-17. The abrasion resistance is evaluated by the mass loss of the sample before and after the friction test. The greater the mass loss, the worse the abrasion resistance; the smaller the mass loss, the better the abrasion resistance. The number of test samples is n=5, and the average value is calculated.

[0086] Table 1 shows the test results of friction coefficient, surface roughness, and wear resistance of the bow hair composite materials in Examples 1 and 6.

[0087] Table 1: Test results of friction coefficient, surface roughness, and wear resistance of the bow hair composite materials prepared in Example 1 and Comparative Examples 1-6

[0088] As can be seen from Table 1, the bow hair composite material of the present invention has good friction performance and wear resistance, demonstrating a balanced advantage in friction performance and wear resistance.

[0089] The friction and wear resistance of the composite materials of Comparative Examples 1, 4, 5, and 6 were generally worse than those of Example 1, indicating that PA, corundum powder, and rosin powder are indispensable in this invention, and the synergistic effect of the three can achieve good friction and wear resistance.

[0090] The friction and wear resistance of the bow hair composite material in Comparative Example 2 were worse than those in Example 1, indicating that chemical surface treatment plays an important role in improving the friction and wear resistance of materials.

[0091] The friction and wear resistance of natural horsehair in Comparative Example 3 were significantly worse than those in Example 1, indicating that the bow hair composite material of the present invention can achieve better results than the prior art in terms of friction and wear resistance. It also shows that by using PA, corundum powder, and rosin powder in combination with surface treatment, the friction and wear resistance of the material can be significantly improved.

[0092] In Comparative Example 4, EVA fibers tend to exhibit adhesive wear in actual friction tests, resulting in a higher coefficient of friction but a significant decrease in wear resistance, making them unsuitable as bow hair materials.

[0093] Furthermore, the inventors used a reciprocating friction test (the specific test method is the same as the friction coefficient test described above) to simulate the performance process, setting the same load and number of cycles, and using a decrease in the friction coefficient to 50% of the initial value or fiber breakage as the material "failure" standard. Tests showed that natural horsehair exhibited a significant decrease in friction after approximately 3000-5000 cycles, while the bow hair composite material of Example 1 of this invention maintained stable friction performance after 8000-10000 cycles. Therefore, the service life of the bow hair composite material of this invention is at least twice that of natural horsehair. This "lifespan improvement" is the result of the synergistic effect of the specific matrix PA66, corundum powder, and rosin powder, combined with surface modification processes.

[0094] Meanwhile, the maximum relative fluctuation of the friction properties of the bow hair composite materials obtained in Example 1 and Comparative Examples 1-6 was tested, and the test method is as follows: Instrument: Micro-motion reciprocating friction and wear testing machine, equipped with a real-time friction coefficient acquisition system (data acquisition rate ≥100Hz). Reference standard: Refer to ASTM G133 test apparatus and fixture configuration (for reciprocating linear / point contact friction testing). Test parameters: normal load 0.5N, sliding speed 10mm / s, reciprocating stroke 5mm, number of cycles 1000, ambient temperature 23±2℃, relative humidity 50±5%; Number of samples: n=5 samples per group (5 independent samples are prepared and tested separately in the same group); Data acquisition: Frictional force and normal force are acquired in real time, and the instantaneous friction coefficient μ(t) is calculated as frictional force / normal force; the sampling frequency is set to 100Hz. Record the instantaneous friction coefficient μ(t) after removing the break-in period (first 50 times), calculate the peak value μ_max, valley value μ_min and arithmetic mean μ_mean for each test, and calculate the maximum relative fluctuation R of a single test according to the following formula.

[0095] R = ((μ_max - μ_min) / μ_mean) × 100%.

[0096] Through testing and calculation, the maximum relative fluctuation (%) of the frictional properties of the bow hair composite materials obtained in Example 1 and Comparative Examples 1-6 were <5%, 6-8%, 12-15%, 15-20%, 8-10%, 7-9%, and 9-11%, respectively. This indicates that under environmental conditions of 23±2℃ and 50±5% relative humidity, the maximum relative fluctuation of the friction coefficient of the bow hair composite material of the present invention is <5% (n=5), which is significantly better than the 15-20% fluctuation range of the same batch of natural horsehair, and also better than the fluctuation range of other comparative examples. This demonstrates that the bow hair composite material of the present invention has good frictional performance stability, that is, good performance reliability, is not easily affected by small environmental changes, and has good environmental adaptability.

[0097] Meanwhile, because the friction coefficient of the bow hair composite material of this invention fluctuates little, has a long service life, and good wear resistance, it also has obvious advantages in terms of durability.

[0098] 4. Mechanical property testing The mechanical properties of the bow hair composite materials prepared in Examples 1-4 and Comparative Examples 1-6 were tested according to ASTM D3822.

[0099] The mechanical property test results of the bow hair composite materials in Examples 1-4 and Comparative Examples 1-6 are as follows: Figure 7 As shown, by Figure 7 The tensile strength and elongation at break of the bow hair composite materials of Examples 1-4 and Comparative Examples 1-6 were obtained, as shown in Table 2.

[0100] Table 2: Tensile strength and elongation at break of the bow hair composite materials of Examples 1-4 and Comparative Examples 1-6

[0101] As can be seen from Table 2, the bow hair composite material of the present invention has good overall mechanical properties.

[0102] Comparative Example 1 used wollastonite to replace part of the corundum powder, while Comparative Example 6 used wollastonite to completely replace the corundum powder. This resulted in the mechanical properties of the bow hair composite materials in Comparative Examples 1 and 6 being inferior to those in Example 1. This demonstrates that the filler in this invention requires specific selection; only by using specific corundum powder, PA66, and rosin powder in combination can the bow hair composite material achieve good mechanical properties.

[0103] Furthermore, in Comparative Example 4, EVA was used to replace an equal amount of PA66, resulting in a lower tensile strength and a higher elongation at break compared to Example 1. However, the surface roughness and wear resistance of Comparative Example 4 were significantly worse than those of Example 1. In Comparative Example 5, PA66 was used to replace an equal amount of rosin powder, resulting in a lower tensile strength and a higher elongation at break compared to Example 1. However, the wear resistance of Comparative Example 5 was worse than that of Example 1.

[0104] As explained above, the present invention uses a specific base material, filler and rosin powder compound to effectively balance the relationship between mechanical properties, wear resistance and friction properties, so that the bow hair composite material has good comprehensive performance in terms of mechanical properties, wear resistance and friction properties.

[0105] Comparative Example 2 underwent no chemical surface treatment and was directly subjected to micro-nano mechanical grinding, resulting in significantly inferior mechanical properties of the bow hair composite material compared to Example 1. This demonstrates that the present invention, employing a combination of chemical surface treatment and micro-nano mechanical grinding, can impart excellent mechanical properties to the bow hair composite material.

[0106] Comparative Example 3 used commercially available natural horsehair without any chemical or physical surface treatment, resulting in a lower tensile strength and higher elongation at break compared to Example 1. While natural horsehair exhibits good flexibility, it has limitations in strength, and its friction and abrasion resistance are significantly worse than those of Example 1. This demonstrates that the bow hair composite material of the present invention has superior overall performance in terms of mechanical properties, abrasion resistance, and friction compared to commercially available natural horsehair.

[0107] Meanwhile, after testing, the bow hair composite materials prepared in Examples 2-4 of this invention also have good comprehensive performance in terms of mechanical properties, wear resistance, and friction properties.

[0108] In summary, this invention utilizes rosin powder, a specific type of substrate, and fillers, which work synergistically, combined with surface treatment processes, to achieve a good balance between mechanical properties, wear resistance, and friction properties in the bow hair composite material. This results in the bow hair composite material exhibiting excellent comprehensive performance in terms of mechanical properties, wear resistance, and friction properties.

[0109] The above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the essence and scope of the technical solutions of the present invention.

Claims

1. A composite material for bow hair, characterized in that, Includes a substrate, and fillers and rosin powder dispersed in the substrate; The substrate is polyamide; The filler is corundum powder.

2. The bow hair composite material according to claim 1, characterized in that, In the bow hair composite material, the filler has a mass percentage of 4.5-17%; and / or, in the bow hair composite material, the rosin powder has a mass percentage of 1.8-11%.

3. The bow hair composite material according to claim 1, characterized in that, The ratio of the mass of the substrate to the sum of the masses of the filler and rosin powder is (2-11):1; and / or the mesh size of the corundum powder is 700-900 mesh.

4. The bow hair composite material according to any one of claims 1-3, characterized in that, The friction coefficient of the bow hair composite material is 0.34-0.40; and / or the surface roughness of the bow hair composite material is 0.80-0.90 μm.

5. The method for preparing the bow hair composite material according to any one of claims 1-4, characterized in that, The preparation method includes the following steps: (1) The substrate, filler and rosin powder are mixed and melt-spun to obtain bow hair fibers; (2) The bow hair fibers are subjected to chemical surface treatment and physical surface treatment to obtain the bow hair composite material.

6. The preparation method according to claim 5, characterized in that, In step (1), the mixing process further includes melt mixing using an extruder.

7. The preparation method according to claim 5, characterized in that, In step (1), the temperature of the melt spinning is 250-285℃; and / or, the diameter of the bow hair fiber is 110-220μm.

8. The preparation method according to claim 5, characterized in that, In step (2), the chemical surface treatment includes any one of oxidation treatment, acid treatment, and swelling treatment; and / or, the physical surface treatment includes mechanical grinding.

9. The preparation method according to claim 8, characterized in that, When the chemical surface treatment includes an oxidation treatment, the reagent used in the oxidation treatment includes at least one of hydrogen peroxide and potassium permanganate; and / or, when the chemical surface treatment includes an acid treatment, the reagent used in the acid treatment includes formic acid; and / or, when the chemical surface treatment includes a swelling treatment, the reagent used in the swelling treatment includes dimethylformamide.

10. A musical instrument, characterized in that, Includes the bow hair composite material as described in any one of claims 1-4.

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