Electron beam irradiation modification method for bamboo toothbrush handle

Abstract

The invention discloses an electron beam irradiation modification method for a bamboo toothbrush handle, which adopts an electron beam with the energy of 10MeV, and improves the mechanical property, the mildew-proof property and the shelf life of the bamboo toothbrush handle by changing the irradiation dose. And as the irradiation dose is increased from 10kGy to 200kGy, the mildew-proof effect of the bamboo wood product is enhanced, and the shelf life is prolonged. When the electron beam irradiation dose is 10-50kGy, the hydrophilic and hydrophobic properties of the surface of the bamboo product are basically unchanged; and when the irradiation dose is 100-200kGy, the surface hydrophobicity of the bamboo product is enhanced, and the compressive strength is increased. The toothbrush handle irradiated by the electron beam is enhanced in mildew resistance, and the shelf life is obviously prolonged compared with that of a product which is not irradiated. The electron beam irradiation method adopted by the invention is a green and environment-friendly irradiation technology, and the bamboo toothbrush handle is treated by electron beams, so that not only is the appearance of the product not damaged, but also the natural structure of the product can be completely maintained, the compressive strength and the mildew-proof performance are enhanced, and the shelf life is effectively prolonged.

Description

Technical Field

[0001] The invention relates to an electron beam irradiation modification method for a bamboo toothbrush handle, and particularly relates to improving the mechanical properties and mildew resistance of the bamboo by using high-energy electron beam irradiation treatment. Background Art

[0002] The widespread use of plastic products in today's society poses a serious threat to the Earth's ecology and human health. Bamboo offers excellent toughness, strength, plasticity, and processing properties, and is closest to wood in terms of form and properties. Bamboo also has a short growth cycle and high yield, making it easy to manage sustainably and utilize once-planted trees sustainably. Furthermore, bamboo comes in many varieties, each with its own unique characteristics, allowing selection based on performance requirements. However, bamboo is highly hydrophilic and its dimensions easily shift with environmental, temperature, and humidity changes, complicating subsequent processing and utilization. Furthermore, bamboo's high content of nutrients, such as starch, protein, and sugars, makes it highly susceptible to mold during processing, transportation, and use. This mold not only destroys the appearance, color, and natural texture of the material and its products, but also reduces its mechanical properties, such as impact toughness, to a certain extent, severely impacting the usability of the material and its products. Therefore, anti-mold modification of bamboo is of great significance.

[0003] Currently, there are four main methods for mildew-proofing bamboo: physical treatment, chemical modification, biological treatment, and irradiation modification. Traditional physical and chemical treatment methods struggle to balance environmental friendliness, green environmental protection, and performance enhancement. Irradiation treatment, which utilizes high-energy radiation to treat bamboo, offers the advantages of long-lasting effectiveness, environmental friendliness, and pollution-free performance, significantly reducing the harmful effects of the processing process on humans and the environment. Among irradiation treatment technologies, electron beam irradiation offers unique advantages and safety features. Electron beam irradiation uses an electron accelerator to generate high-energy electron beams, transferring their energy to the irradiated material, causing physical, chemical, or biological effects on the material, achieving the goals of disinfection, sterilization, and desired modification. As a new environmentally friendly technology, electron beam treatment features low reaction temperatures, short reaction times, low costs, and no strict requirements for the materials being treated, making it universally adaptable. Electron beam irradiation modification technology has obvious advantages over traditional gamma ray irradiation methods. It can not only be processed in a cycle to meet any processing quantity, but also does not require post-processing time. Especially compared with cobalt 60 (gamma ray) irradiation, there is no radiation after shutdown, and no radioactive waste source will be generated, which is safer and more reliable.

[0004] Therefore, electron beam irradiation technology is expected to become a powerful technical means for modifying bamboo products. Summary of the Invention

[0005] Based on the above analysis, the present invention provides a high-energy electron beam treatment method for enhancing the mechanical properties and mildew resistance of bamboo products. This method uses a 10MeV electron beam to modify a bamboo toothbrush handle and provides a dosage range for extending the shelf life of the bamboo.

[0006] The technical solutions of the present invention are as follows:

[0007] A method for modifying a bamboo toothbrush handle by electron beam irradiation comprises the following steps:

[0008] (1) The bamboo toothbrush handle was subjected to a 10 MeV electron beam modification treatment in air. When the electron beam irradiation dose was 10 to 30 kGy, the interaction between the fibers was destroyed by the irradiation, the molecular chains were broken, the grain size of the bamboo was reduced, and the interplanar spacing was also reduced. The hydrophilicity of the bamboo surface was slightly enhanced, making it unsuitable for long-term storage in a humid environment. At this time, the structure of the bamboo did not change significantly, but its compression resistance was enhanced.

[0009] (2) When the irradiation dose is 50-100 kGy, the molecular structure of bamboo fibers undergoes cross-linking, the grain size of bamboo gradually increases, and the inter-crystalline spacing increases; the mechanical properties of bamboo are enhanced.

[0010] (3) When the electron beam irradiation was between 100 and 200 kGy, the microbial components in the bamboo matrix died due to the high-energy radiation, and nutrients such as starch changed due to the irradiation, which significantly enhanced the anti-mildew properties of the bamboo. Compared with the unirradiated bamboo, the mildew of the irradiated bamboo was delayed by more than one month. The mechanical properties of the bamboo continued to maintain a high level. In addition, the hydrophobicity of the toothbrush handle surface was enhanced, extending the service life of the toothbrush handle in a humid environment.

[0011] The beneficial effects of the present invention are:

[0012] The electron beam irradiation modification method provided by the present invention has no strict requirements on the size of the processed materials and the environment, and overcomes the adverse effects of the material size and shape on the processing technology during the processing of bamboo products. Compared with traditional gamma-ray irradiation, electron beam irradiation technology has the advantages of large emission power, adjustable energy, short processing time, high utilization rate, no need to regularly replenish the radiation source, and simpler safety protection standards. The use of electron beam irradiation technology instead of chemical modification methods greatly avoids the harm of the processing process to the human body and the environment. According to the bamboo toothbrush handle provided by this modification method, under a certain irradiation dose, the mechanical properties and mildew-proof effect are more obvious due to the increase in irradiation dose, mildew is delayed for more than one month, and the compressive strength is increased by more than 4 times. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 This is the XRD pattern of the bamboo material after irradiation treatment in Example 1 of the present invention;

[0014] Figure 2 This is the compressive stress-strain curve of the bamboo material after irradiation treatment in Example 1 of the present invention;

[0015] Figure 3 This is the mildew condition of the bamboo after irradiation treatment in Example 1 of the present invention. DETAILED DESCRIPTION

[0016] The following examples are provided to illustrate the present invention but are not intended to limit the scope of the present invention. Any modification or substitution of the methods, steps or conditions of the present invention without departing from the spirit and substance of the present invention shall fall within the scope of the present invention.

[0017] Example 1

[0018] (1) Soak the bamboo toothbrush handle in 75% ethanol solution for 1 min to disinfect the bamboo surface. After wiping it dry, place it in a vacuum oven at 60°C to dry the ethanol solution remaining on the surface.

[0019] (2) The bamboo toothbrush handles were placed in an irradiation chamber and modified using a 10 MeV electron beam. The irradiation doses were selected as 10, 30, 50, 100, and 150 kGy.

[0020] (3) The unirradiated and irradiated toothbrush handles were cut into small pieces and placed together in a constant temperature and humidity chamber at a temperature of 30-35°C and a humidity of 60-80%. The surface mold of the toothbrush handles was observed after 240 days, and the mold time of the toothbrush handles treated with different irradiation doses was recorded.

[0021] (4) The unirradiated and irradiated toothbrush handles were subjected to XRD and compressive strength tests.

[0022] Example 2

[0023] (1) Soak the bamboo toothbrush handle in 75% ethanol solution for 1 min to disinfect the bamboo surface. After wiping it dry, place it in a vacuum oven at 60°C to dry the ethanol solution remaining on the surface.

[0024] (2) The bamboo toothbrush handles were placed in an irradiation chamber and modified using a 10 MeV electron beam. The irradiation doses were selected as 20, 30, 40, 110, and 200 kGy.

[0025] (3) The unirradiated and irradiated toothbrush handles were cut into small pieces and placed together in a constant temperature and humidity chamber at a temperature of 30-35°C and a humidity of 60-80%. The surface mold of the toothbrush handles was observed after 240 days, and the mold time of the toothbrush handles treated with different irradiation doses was recorded.

[0026] (4) The unirradiated and irradiated toothbrush handles were subjected to XRD and compressive strength tests.

[0027] Example 3

[0028] (1) Soak the bamboo toothbrush handle in 75% ethanol solution for 1 min to disinfect the bamboo surface. After wiping it dry, place it in a vacuum oven at 60°C to dry the ethanol solution remaining on the surface.

[0029] (2) The bamboo toothbrush handles were placed in an irradiation chamber and modified using a 10 MeV electron beam. The irradiation doses were selected as 30, 60, 90, 120, and 150 kGy.

[0030] (3) The unirradiated and irradiated toothbrush handles were cut into small pieces and placed together in a constant temperature and humidity chamber at a temperature of 30-35°C and a humidity of 60-80%. The surface mold of the toothbrush handles was observed after 240 days, and the mold time of the toothbrush handles treated with different irradiation doses was recorded.

[0031] (4) The unirradiated and irradiated toothbrush handles were subjected to XRD and compressive strength tests.

[0032] Test Example 1

[0033] X-ray inspection of the bamboo toothbrush handle after irradiation treatment in Example 1 of the present invention

[0034] Example 1 The XRD pattern of the bamboo toothbrush handle after irradiation treatment is as follows Figure 1 As shown, unirradiated bamboo exhibits distinct diffraction peaks at 2θ≈22° and 2θ≈16°, which are characteristic diffraction peaks of cellulose I. These peaks are still observed in all irradiated bamboo samples, indicating that irradiation does not alter the crystal structure of bamboo cellulose. However, after irradiation, the intensity of the diffraction peaks decreases, indicating that electron beam irradiation reduces the proportion of crystalline cellulose in the bamboo cellulose system.

[0035] Test Example 2

[0036] Changes in mechanical behavior of the bamboo toothbrush handle after irradiation treatment in Example 1 of the present invention under compression load

[0037] The compressive stress-strain curve of the bamboo toothbrush handle after irradiation treatment in Example 1 is as follows: Figure 2 As shown, the strain of unirradiated bamboo is 16%, while the strain of electron beam irradiated bamboo increases. When the irradiation dose increases to 100 kGy and 150 kGy, the strain of irradiated bamboo increases to 69% and 70%, respectively. Furthermore, the elastic modulus of bamboo irradiated with 150 kGy is the highest, at approximately 1305 MPa. This indicates that the compressive resistance of bamboo increases with increasing irradiation dose.

[0038] Test Example 3

[0039] The mildew of the bamboo toothbrush handle after irradiation treatment in Example 1 of the present invention was observed.

[0040] Example 1 The mildew condition of the bamboo toothbrush handle after irradiation treatment is as follows Figure 3 As shown in the figure: Under the same humidity and temperature environment, as the irradiation dose increases, the irradiated bamboo becomes moldy significantly later than the non-irradiated bamboo, and the greater the irradiation dose, the later the mold appears.

[0041] Researchers have used radionuclides 60 Co and 137 The bamboo is irradiated with Cs gamma rays. 60 Co is the most widely used. In the field of bamboo irradiation modification, researchers have used gamma-ray irradiation to treat bamboo and studied the effects of different irradiation doses on the micromorphology, mechanical properties and chemical properties of bamboo. However, in recent years, with the continuous increase in the price of international cobalt sources, 60 The investment cost of Co irradiation increases accordingly, and the operating cost also increases significantly; at the same time, in practical applications, due to 60 Co irradiation processing has the disadvantages of relatively low efficiency and serious nuclear waste pollution. 60 Co's development has strengthened management and control, 60 Co irradiation technology is being phased out.

[0042] Although the present invention is described herein with reference to illustrative embodiments of the present invention, the above embodiments are merely preferred embodiments of the present invention, and the embodiments of the present invention are not limited to the above embodiments. Those skilled in the art can design many other modifications and implementations, and these modifications and implementations will fall within the scope and spirit of the principles disclosed in this application.

Claims

1. A method for modifying a bamboo toothbrush handle by electron beam irradiation, comprising: The bamboo toothbrush handle is placed in an irradiation chamber and modified by a 10 MeV electron beam, with an irradiation dose of 10 to 200 kGy.

2. The electron beam irradiation modification method according to claim 1, wherein: The bamboo toothbrush handle further comprises: Soak the bamboo toothbrush handle in 75% ethanol solution for 1 minute, wipe it dry, and place it in a vacuum oven at 60°C to dry the residual ethanol solution on the surface. Set aside.

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