Copper-free resin-based brake material prepared from waste textile fibers

Abstract

The invention discloses a copper-free resin-based brake material prepared from waste textile fibers, and belongs to the technical field of brake materials. The composite material is prepared from the following raw materials in percentage by mass: 5-9 parts of waste textile fibers, 10-20 parts of foundry waste sand, 15-25 parts of cashew nut shell oil modified phenolic resin, 20-25 parts of aluminum oxide, 13-42 parts of barite, 5 parts of butyronitrile powder and 3 parts of graphite. According to the copper-free resin-based brake material, the waste textile fiber is adopted as a reinforcing component to be added into the copper-free resin-based brake material, and good mechanical strength, wear resistance and flexibility of the waste textile fiber are utilized, so that the friction coefficient stability, heat fading resistance and wear resistance of the friction material are remarkably improved; the material cost is effectively reduced while copper-free treatment of the brake material is realized, high-valued resource utilization of waste textiles is realized, and the brake material has good engineering application value and remarkable economic and social benefits.

Description

Technical Field

[0001] This invention belongs to the field of braking material technology, specifically relating to a copper-free resin-based braking material prepared using waste textile fibers. Background Technology

[0002] Traditional resin-based braking materials often use asbestos or copper as reinforcing or thermally conductive components. However, asbestos is banned due to its carcinogenic risks, and copper is restricted or prohibited by regulations in many countries because it generates copper-containing dust during braking, which pollutes water bodies. Existing copper-free braking materials mostly use aramid, carbon fiber, mineral fiber, or metal fiber as alternative reinforcing materials. These materials are costly and difficult to process, hindering large-scale promotion. Therefore, how to ensure that resin-based braking materials are copper-free while also being low-cost, environmentally friendly, and high-performance has become a key research topic in recent years for novel resin-based braking materials.

[0003] Data from the United Nations Environment Programme shows that approximately 92 million tons of textiles are discarded globally each year, and the global scale of waste textiles is projected to reach 134 million tons by 2025. Data from the National Development and Reform Commission shows that the total amount of waste textiles exceeded 20 million tons in 2020, but the comprehensive utilization rate was less than 20%. Empirical research by the International Solid Waste Association indicates that microplastic particles released from every kilogram of polyester clothing in landfills can undergo a 140-fold bioaccumulation effect through groundwater infiltration, causing a serious environmental burden. This invention successfully improves the frictional performance of copper-free resin-based braking materials using waste textile fibers, providing a theoretical basis for the development of high-performance resin-based braking materials, and also offering a promising approach for the reuse of waste textiles. Summary of the Invention

[0004] The purpose of this invention is to provide a copper-free resin-based braking material reinforced with waste textile fibers and its preparation method. By applying waste textiles to braking materials, a high-performance, copper-free, low-cost, and environmentally friendly braking material is prepared.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: A copper-free resin-based braking material prepared from waste textile fibers is made from the following raw materials in parts by weight: 5-9 parts waste textile fibers, 10-20 parts foundry waste sand, 15-25 parts cashew nut shell oil modified phenolic resin, 20-25 parts alumina, 13-42 parts barite, 5 parts nitrile powder, and 3 parts graphite.

[0006] Furthermore, the waste textile fibers are a blend of 80 wt.% polyester fibers and 20 wt.% cotton fibers.

[0007] The preparation of the copper-free resin-based braking material includes the following steps: 1) Treatment of textile fibers: The textile fibers are cut to obtain textile fibers with a length of 5-30 mm and a width of 5 mm. 2) Drying of raw materials: Cashew shell oil modified phenolic resin, sheared textile fibers, and nitrile powder are dried at 60-70℃ for 60 minutes, while foundry waste sand, alumina, barite, and graphite are dried at 110-120℃ for 120 minutes respectively. 3) Uniform mixing: Weigh the dried raw materials according to the proportion and put them into the mixer for short-term high-frequency stirring to make the materials uniformly mixed; 4) Hot pressing: The mixture obtained in step 3) is placed in a hydraulic press for hot pressing; 5) Heat treatment: The hot-pressed sample is placed in an electric heating constant temperature drying oven and heat-treated at 160℃ for 12 hours, and then cooled with the oven to obtain the metal-free resin-based braking material.

[0008] Furthermore, the total stirring time for the short-term high-frequency stirring described in step 3) is 5 to 8 minutes, and the stirring time for each stirring session does not exceed 10 seconds.

[0009] Furthermore, in step 4), the hot pressing temperature is 165~170℃, the pressure is 10MPa, the holding time is 6min, and the air is vented 2~3 times during the process.

[0010] The resulting resin-based braking material does not contain copper or other heavy metal components that are harmful to the human body. Its coefficient of friction at 300~350℃ is above 0.44 and not lower than the coefficient of friction at 100℃.

[0011] The main components of waste textile fibers are polyester and cotton fibers, which have certain mechanical strength, abrasion resistance, and flexibility. Polyester fibers have good heat resistance and high strength, while cotton fibers have excellent flexibility and low cost. Adding them as reinforcing components to brake materials can not only realize the high-value reuse of waste textiles and turn waste into treasure, but also significantly improve the high-temperature frictional stability of brake materials and reduce thermal fade. The beneficial effects of this invention are as follows:

[0012] By utilizing waste textile fibers to enhance the friction properties of copper-free resin-based braking materials, waste textiles can be reused, reducing environmental pollution.

[0013] This invention uses waste textile fibers to reinforce copper-free resin-based braking materials. The developed resin-based braking materials not only have excellent friction and wear performance at high temperatures, but also have low cost. Detailed Implementation

[0014] The technical solution of the present invention will be further described below with reference to specific embodiments. It is obvious that the described embodiments are merely some embodiments of the present invention, and not all embodiments.

[0015] When not specified, the waste textile fibers used are a mixture of 80% polyester fibers and 20% cotton fibers.

[0016] The foundry waste sand was purchased from Fuzhou Zhongfu Water Meter Co., Ltd., with a particle size of 60-200 mesh, and was used as a filler phase.

[0017] Cashew nut shell oil-modified phenolic resin was purchased from Fujian Guanliang Auto Parts Industry Co., Ltd., with a mesh size of 60-100 mesh, and was used as a matrix binder phase. Example 1

[0018] 1) Composition of raw materials (by mass parts) 5 parts of waste textile fiber (25mm long, 5mm wide), 10 parts of foundry waste sand, 20 parts of cashew shell oil modified phenolic resin, 20 parts of alumina, 37 parts of barite, 5 parts of nitrile powder, and 3 parts of graphite.

[0019] 2) Preparation method: Textile fibers were sheared to obtain textile fibers 25 mm long and 5 mm wide. Resin, the sheared textile fibers, and nitrile powder were dried at 60 °C for 30 min, while foundry waste sand, alumina, barite, and graphite were dried at 120 °C for 60 min. The dried raw materials were placed in a mixer and stirred for 8 min (each stirring time not exceeding 10 s) to ensure uniform mixing. The uniformly mixed material was placed in a hydraulic press and hot-pressed at 165 °C and 10 MPa for 6 min, with venting twice during the process. The hot-pressed sample was then heat-treated at 160 °C for 12 h and cooled in the furnace to obtain the copper-free resin-based braking material. Example 2

[0020] 1) Composition of raw materials (by mass parts) 7 parts of waste textile fiber (25mm long, 5mm wide), 10 parts of foundry waste sand, 25 parts of cashew shell oil modified phenolic resin, 25 parts of alumina, 35 parts of barite, 5 parts of nitrile powder, and 3 parts of graphite.

[0021] 2) Preparation method: Textile fibers were sheared to obtain textile fibers 25 mm long and 5 mm wide. Resin, the sheared textile fibers, and nitrile powder were dried at 60 °C for 30 min, while foundry waste sand, alumina, barite, and graphite were dried at 120 °C for 60 min. The dried raw materials were placed in a mixer and stirred for 8 min (each stirring time not exceeding 10 s) to ensure uniform mixing. The uniformly mixed material was placed in a hydraulic press and hot-pressed at 165 °C and 10 MPa for 6 min, with venting twice during the process. The hot-pressed sample was then heat-treated at 160 °C for 12 h and cooled in the furnace to obtain the copper-free resin-based braking material. Example 3

[0022] 1) Composition of raw materials (by mass parts) Nine parts of waste textile fiber (25mm long, 5mm wide), ten parts of foundry waste sand, twenty parts of cashew shell oil modified phenolic resin, twenty parts of alumina, thirty-three parts of barite, five parts of nitrile powder, and three parts of graphite.

[0023] 2) Preparation method: Textile fibers were sheared to obtain textile fibers 25 mm long and 5 mm wide. Resin, the sheared textile fibers, and nitrile powder were dried at 60 °C for 30 min, while foundry waste sand, alumina, barite, and graphite were dried at 120 °C for 60 min. The dried raw materials were placed in a mixer and stirred for 8 min (each stirring time not exceeding 10 s) to ensure uniform mixing. The uniformly mixed material was placed in a hydraulic press and hot-pressed at 165 °C and 10 MPa for 6 min, with venting twice during the process. The hot-pressed sample was then heat-treated at 160 °C for 12 h and cooled in the furnace to obtain the copper-free resin-based braking material. Example 4

[0024] 1) Composition of raw materials (by mass parts) Nine parts of waste textile fiber (25mm long, 5mm wide), ten parts of foundry waste sand, 25 parts of cashew shell oil modified phenolic resin, 25 parts of alumina, 23 parts of barite, five parts of nitrile powder, and three parts of graphite.

[0025] 2) Preparation method: Textile fibers were sheared to obtain textile fibers 25 mm long and 5 mm wide. Resin, the sheared textile fibers, and nitrile powder were dried at 60 °C for 30 min, while foundry waste sand, alumina, barite, and graphite were dried at 120 °C for 60 min. The dried raw materials were placed in a mixer and stirred for 8 min (each stirring time not exceeding 10 s) to ensure uniform mixing. The uniformly mixed material was placed in a hydraulic press and hot-pressed at 165 °C and 10 MPa for 6 min, with venting twice during the process. The hot-pressed sample was then heat-treated at 160 °C for 12 h and cooled in the furnace to obtain the copper-free resin-based braking material. Example 5

[0026] 1) Composition of raw materials (by mass parts) 7 parts of waste textile fiber (20mm long, 5mm wide), 10 parts of foundry waste sand, 25 parts of cashew shell oil modified phenolic resin, 25 parts of alumina, 35 parts of barite, 5 parts of nitrile powder, and 3 parts of graphite.

[0027] 2) Preparation method: Textile fibers were sheared to obtain textile fibers 20 mm long and 5 mm wide. Resin, the sheared textile fibers, and nitrile powder were dried at 60 °C for 30 min, while foundry waste sand, alumina, barite, and graphite were dried at 120 °C for 60 min. The dried raw materials were placed in a mixer and stirred for 8 min (each stirring time not exceeding 10 s) to ensure uniform mixing. The uniformly mixed material was placed in a hydraulic press and hot-pressed at 165 °C and 10 MPa for 6 min, with venting twice during the process. The hot-pressed sample was then heat-treated at 160 °C for 12 h and cooled in the furnace to obtain the copper-free resin-based braking material. Comparative Example 1

[0028] 1) Composition of raw materials (by mass parts) 0 parts waste textile fiber, 10 parts foundry waste sand, 20 parts cashew shell oil modified phenolic resin, 20 parts alumina, 42 parts barite, 5 parts nitrile powder, and 3 parts graphite.

[0029] 2) Preparation method: The resin and nitrile powder were dried at 60 °C for 30 min, and the foundry waste sand, alumina, barite and graphite were dried at 120 °C for 60 min. The dried raw materials were put into a mixer and stirred for 8 min (each stirring time not exceeding 10 s) to ensure uniform mixing. The uniformly mixed material was placed in a hydraulic press and hot-pressed at 165 °C and 10 MPa for 6 min, with venting twice during the process. The hot-pressed sample was heat-treated at 160 °C for 12 h and then cooled in the furnace to obtain the copper-free resin-based braking material.

[0030]

[0031]

[0032] According to the test results of friction coefficient and wear rate in Tables 1 and 2, it can be found that the friction coefficient and wear rate of the brake materials prepared in the examples are both within the allowable range of the national standard, with Example 2 showing the best performance. Furthermore, compared with the resin-based brake material without textile fibers prepared in the comparative examples, the copper-free resin-based brake material reinforced with waste textile fibers in the embodiments of this invention exhibits significantly superior resistance to thermal fading and higher friction coefficient stability. This proves that the present invention effectively solves the high-temperature thermal fading problem of copper-free brake materials through the optimized addition of waste textile fibers, while simultaneously achieving high-value reuse of waste textiles. This is of great significance for promoting the environmental protection, greening, and sustainable development of my country's brake material industry.

[0033] The above description is only a preferred embodiment of the present invention. All equivalent changes and modifications made within the scope of the claims of the present invention should be included in the scope of the present invention.

Claims

1. A copper-free resin-based braking material prepared from waste textile fibers, characterized in that: It is made from the following raw materials in parts by weight: 5-9 parts waste textile fiber, 10-20 parts foundry waste sand, 15-25 parts cashew shell oil modified phenolic resin, 20-25 parts alumina, 13-42 parts barite, 5 parts nitrile powder, and 3 parts graphite.

2. The copper-free resin-based braking material according to claim 1, characterized in that: The waste textile fibers are a blend of 80 wt.% polyester fibers and 20 wt.% cotton fibers.

3. A method for preparing the copper-free resin-based braking material as described in claim 1 or 2, characterized in that: Includes the following steps: 1) Treatment of waste textile fibers: The waste textile fibers are cut to obtain textile fibers with a length of 5-30mm and a width of 5mm. 2) Drying of raw materials: Dry cashew shell oil-modified phenolic resin, sheared textile fibers and nitrile powder at 60-70℃ for 60 minutes, and dry foundry waste sand, alumina, barite and graphite at 110-120℃ for 120 minutes. 3) Uniform mixing: The dried raw materials are stirred at a high frequency for a short time to ensure uniform mixing; 4) Hot pressing: The mixed material obtained in step 3) is hot pressed into shape; 5) Heat treatment: The hot-pressed material is heat-treated at 160°C for 12 hours and then cooled in the furnace to obtain the copper-free resin-based braking material.

4. The method according to claim 3, characterized in that: The total stirring time for the short-term high-frequency stirring described in step 3) is 5 to 8 minutes, and the stirring time for each stirring session shall not exceed 10 seconds.

5. The method according to claim 3, characterized in that: The hot pressing temperature in step 4) is 165~170℃, the pressure is 10MPa, the holding time is 6min, and the air is vented 2~3 times during the process.

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