Degradable bamboo wood pulp composite material, production method thereof and application of degradable bamboo wood pulp composite material in safety helmet production

Abstract

The invention provides a degradable bamboo wood pulp composite material and a production method and application thereof in safety helmet production, and belongs to the technical field of high polymer materials, the degradable bamboo wood pulp composite material takes bamboo chips or wood chips as base materials, and scandium, coumarone resin, a cross-linking agent, caustic soda, a hydrophobic modifier, a deinking agent, a sizing agent, an antioxidant and stearic acid as auxiliary materials. Compared with the prior art, scandium is adopted as a medium material for chemical modification of the bamboo and wood pulp fibers for the first time, the compatibility of the interiors and interfaces of the bamboo and wood pulp fibers is remarkably enhanced, the bonding density of all the raw materials is greatly improved, and the mechanical strength and performance of the composite material are guaranteed. And the produced safety helmet can be degraded within 180-360 days. Compared with traditional safety helmets and helmets made of glass fiber reinforced plastics, rubber and plastics, the safety helmet made of the degradable bamboo and wood pulp composite material has the remarkable properties of degradability, static electricity resistance, oil stain resistance, water corrosion resistance, puncture resistance and the like.

Description

Technical Field

[0001] This invention belongs to the field of polymer materials technology, specifically relating to a biodegradable bamboo and wood pulp composite material, its production method, and its application in the production of safety helmets. Background Technology

[0002] Currently, safety helmets are important safety equipment in industrial production, safe travel, and explosion protection in various countries around the world. They are used to ensure the personal safety of personnel in industrial production, cycling, explosion protection, and stability maintenance. Every year, various fields require a large number of safety helmets.

[0003] To date, safety helmets and protective helmets produced in various countries are generally made of three materials: 1. fiberglass; 2. rubber; 3. plastic. These three types of safety helmets and protective helmets play a significant role and make a significant contribution to the national economy and personal safety of each country.

[0004] However, these three types of safety helmets have the following disadvantages and shortcomings: fiberglass, rubber, and plastic materials are not only expensive to produce, but also non-degradable and environmentally unfriendly. Defective and waste safety helmets are difficult to dispose of after use. They do not decompose even after being piled up and buried deep for decades. When burned, they produce a large amount of harmful gases, which damages the ecological environment. Their residues are a serious source of pollution.

[0005] For example, patent CN119431698A, published on February 14, 2025, discloses a composite material for safety helmets, its preparation method, and a safety helmet, comprising the following raw materials in parts by weight: 22-27 parts unsaturated polyester, 4-6 parts low profile shrinkage agent, 0.4-0.8 parts highly active initiator, 1.6-2.4 parts internal release agent, 0.2-0.6 parts thickener, 25-35 parts flame retardant, 25-35 parts glass fiber, 0-5 parts internal coloring pigment, and 2-6 parts additives; it has the advantages of improving the heat resistance and production efficiency of safety helmets. However, it is non-degradable and has a high production cost. Summary of the Invention

[0006] The purpose of this invention is to provide a biodegradable bamboo and wood pulp composite material and its production method, which uses bamboo or wood chips as the main material, combined with other auxiliary materials, pulping and heat treatment to obtain a composite material with high strength and toughness.

[0007] Another objective of this invention is to provide an application of a biodegradable bamboo-wood pulp composite material in the production of safety helmets. This biodegradable bamboo-wood pulp composite material, used in the production of safety helmets, possesses advantages such as biodegradability, insulation and antistatic properties, oil resistance, water and corrosion resistance, and puncture resistance. It is suitable for use in coal mines, construction sites, workshops, cycling, security and explosion-proof applications, etc. It features low cost and high strength. It is the best alternative to traditional rubber and plastic safety helmets, solving long-standing pollution problems and is a completely environmentally friendly green product.

[0008] The specific technical solution of this invention is as follows:

[0009] A biodegradable bamboo-wood pulp composite material comprises the following raw materials in parts by weight:

[0010] 40-45 parts bamboo or wood chips; 55-60 parts water; 1-2 parts scandium; 1-3 parts coumarone resin; 5-10 parts crosslinking agent; 2-5 parts caustic soda; 1-2 parts hydrophobic modifier; 1 part deinking agent; 1 part sizing agent; 1 part antioxidant; 1 part stearic acid.

[0011] The biodegradable bamboo and wood pulp composite material has a flexural strength ≥170MPa and an impact toughness ≥110KJ / ㎡.

[0012] The raw material for the bamboo strips is selected from any one or more of moso bamboo and carnation;

[0013] The raw material for the wood chips is selected from wood.

[0014] The crosslinking agent is selected from any one or a mixture of phthalic anhydride, maleic anhydride and pyromellitic anhydride; the phthalic anhydride is phthalic anhydride or isophthalic anhydride.

[0015] The caustic soda is a liquid caustic soda with a sodium hydroxide mass fraction between 30% and 50%.

[0016] The hydrophobic modifier is: DL-171 silane coupling agent.

[0017] The deinking agent is FDMX-9801 liquid deinking agent, produced by Shandong Weifang Mingxiang, with an effective ingredient content of ≥98%. Its function is to effectively remove ink impurities from bamboo pulp, improve the purity of the bamboo pulp, and allow it to fully combine with other mixed raw materials.

[0018] The sizing agent is any one of rosin, alkyl ketene dimer (AKD), or alkenyl succinic anhydride (ASA). Its function is to effectively fill the gaps in the bamboo and wood pulp fibers, forming a dense, waterproof layer on the surface of the safety helmet, thereby achieving excellent waterproof and corrosion-resistant effects.

[0019] The antioxidant is Antioxidant 626: bis(2,4-di-tert-butylphenyl)pentaerythritol diphosphite. Its function is to increase the antioxidant properties of the helmet, stabilize its structural strength within its service life, and prevent premature oxidative decomposition.

[0020] The stearic acid mentioned is domestically produced type 1865. Its function is to enhance the cured state of the safety helmet after compression molding, prevent the safety helmet from deforming or tearing under pressure, thereby significantly improving the physical and mechanical properties of the safety helmet.

[0021] The present invention provides a method for producing a biodegradable bamboo-wood pulp composite material, specifically comprising:

[0022] The formula is prepared by mixing bamboo or wood chips, water, scandium, coumarone resin, crosslinking agent, caustic soda, hydrophobic modifier, deinking agent, sizing agent, antioxidant and stearic acid, and pulping in a pulping machine. The resulting mixture is then heated in a high-speed mixer and thoroughly stirred to obtain the composite material.

[0023] The heating temperature is above 200℃, and the stirring and mixing time is 30-40 minutes.

[0024] The present invention provides an application of a biodegradable bamboo and wood pulp composite material in the production of safety helmets, specifically: the biodegradable bamboo and wood pulp composite material is fed into a molding machine for molding, and then pressed into a biodegradable bamboo and wood pulp composite material safety helmet after being pressurized.

[0025] The safety helmets produced have a head impact force of ≤3960N.

[0026] The safety helmet produced from the biodegradable bamboo and wood pulp composite material provided by this invention involves grinding bamboo or wood chips with other materials in a pulper to obtain bamboo and wood pulp fibers. The resulting mixture is then heated to above 200°C to allow scandium to form an α-type crystalline structure (HCP), which catalyzes the decomposition of hydrogen peroxide in the bamboo and wood pulp, removing all impurities and yielding high-purity bamboo and wood pulp. This alters the original chemical composition and structure of the bamboo and wood pulp, improving its bleaching effect and strength. The added deinking agent catalyzes the decomposition of hydrogen peroxide in the bamboo and wood pulp during the bleaching process, enhancing the bleaching rate and separating impurities such as ink, lignin, pectin, pentosans, and bamboo adhesive, thereby significantly improving the purity and strength of the bamboo and wood pulp. This composite material is then fed to a press to mold the safety helmet. The sizing agent effectively fills the gaps in the bamboo and wood pulp, forming a dense, waterproof layer on the helmet surface, thus achieving excellent waterproof and corrosion-resistant properties. The antioxidant enhances the helmet's antioxidant performance, while stearic acid stabilizes the cured state after the helmet is pressed and molded, preventing deformation from compression and tearing, and significantly enhancing its physical and mechanical properties. This invention ultimately yields a biodegradable, high-strength, waterproof, corrosion-resistant, high-temperature resistant, and puncture-resistant biodegradable bamboo and wood pulp composite material safety helmet.

[0027] This invention uses bamboo or wood chips as the base material, and scandium (HCP), coumarone resin, crosslinking agent, caustic soda, hydrophobic modifier, deinking agent, sizing agent, antioxidant, and stearic acid as auxiliary materials. Compared with existing technologies, this invention is the first to use scandium as a medium to chemically modify bamboo and wood pulp fibers, significantly enhancing the compatibility between the internal structure and interface of the bamboo and wood pulp fibers, greatly increasing the bonding density of all the above raw materials, and ensuring the mechanical strength and performance of the composite material. Furthermore, the raw materials used in production are mainly bamboo and wood chips, which are biodegradable; therefore, the safety helmets produced can degrade within 180-360 days. Compared with traditional fiberglass, rubber, and plastic safety helmets and helmets, the biodegradable bamboo and wood pulp composite safety helmet of this invention has significant properties such as biodegradability, antistatic properties, oil resistance, water and corrosion resistance, and puncture resistance. Its production cost is far lower than that of traditional safety helmets and helmets, making it the best alternative to similar products and solving the long-standing fundamental pollution problem; it is a completely environmentally friendly green product. Detailed Implementation

[0028] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0029] In this invention, unless otherwise specified, all parts and percentages are by weight, and the equipment and raw materials used are commercially available or commonly used in the art. Unless otherwise specified, the methods in the following embodiments are conventional methods in the art. Unless otherwise specified, the components or equipment in the following embodiments are general standard parts or components known to those skilled in the art, and their structures and principles can be learned by those skilled in the art through technical manuals or conventional experimental methods.

[0030] The sources of raw materials used in the various embodiments of this invention are as follows:

[0031] Scandium can be purchased from Zhongkuang Resources, Beijing Gaoke New Materials, and Yourong New Materials.

[0032] Bamboo strips: Purchase two-year-old moso bamboo or stone bamboo from the Jiangsu and Zhejiang areas. The moisture content should not exceed 10%. Use them after crushing.

[0033] Coumarone resin: Fuyang Lipu New Material Technology Co., Ltd.

[0034] Crosslinking agent: Domestic DL-171 silane coupling agent.

[0035] Caustic soda: Domestic sodium hydroxide (NaOH), liquid caustic soda with a sodium hydroxide mass fraction between 30% and 50%;

[0036] Hydrophobic modifier: Domestic DL-171 silane coupling agent.

[0037] Deinking agent: Domestic FDMX-9801 liquid deinking agent.

[0038] Sizing agent: Any one of the following: domestic rosin, alkyl ketene dimer (AKD), and alkenyl succinic anhydride (ASA).

[0039] Antioxidant: Domestic antioxidant 626: bis(2,4-di-tert-butylphenyl) pentaerythritol diphosphite.

[0040] Stearic acid: Domestic type 1865.

[0041] The following are some specific embodiments and comparative examples.

[0042] Example 1

[0043] A biodegradable bamboo-wood pulp composite material comprises the following raw materials in parts by weight:

[0044] Scandium: 1 part;

[0045] Bamboo strips: 40 portions;

[0046] Water: 60 parts;

[0047] Coumarone resin: 1 part;

[0048] Crosslinking agent: 5 parts;

[0049] Sodium hydroxide (NaOH): 2 parts;

[0050] Hydrophobic modifier: 2 parts;

[0051] Deinking agent: 1 part;

[0052] Sizing agent rosin: 1 part;

[0053] Antioxidant: 1 part;

[0054] 1 part stearic acid.

[0055] The bamboo strips, water, scandium, coumarone resin, crosslinking agent, caustic soda, hydrophobic modifier, deinking agent, sizing agent, antioxidant, and stearic acid in the formulation of Example 1 were mixed and pulped in a pulping machine. The resulting mixture was then heated to 200°C in a high-speed mixer and thoroughly stirred for 40 minutes to obtain the composite material. Its flexural strength and impact toughness were tested.

[0056] The application of a biodegradable bamboo-wood pulp composite material in the production of safety helmets specifically involves: feeding the composite material prepared in Example 1 above into a press to press the safety helmet into shape. This is application example 1.

[0057] Example 2

[0058] A biodegradable bamboo-wood pulp composite material comprises the following raw materials in parts by weight:

[0059] Scandium: 2 parts;

[0060] Bamboo strips: 43 pieces;

[0061] Water: 57 parts;

[0062] Coumarone resin: 2 parts;

[0063] Crosslinking agent: 6 parts;

[0064] Sodium hydroxide (NaOH): 3 parts;

[0065] Hydrophobic modifier: 2 parts;

[0066] Deinking agent: 1 part;

[0067] Sizing agent alkyl ketene dimer (AKD): 1 part;

[0068] Antioxidant: 1 part;

[0069] Stearic acid: 1 part.

[0070] The bamboo strips, water, scandium, coumarone resin, crosslinking agent, caustic soda, hydrophobic modifier, deinking agent, sizing agent, antioxidant, and stearic acid in the formulation of Example 2 were mixed and pulped in a pulping machine. The resulting mixture was then heated to 220°C in a high-speed mixer and thoroughly stirred for 35 minutes to obtain the composite material. Its flexural strength and impact toughness were tested.

[0071] The application of a biodegradable bamboo-wood pulp composite material in the production of safety helmets specifically involves: feeding the composite material prepared in Example 2 above into a pressing machine to press the safety helmet into shape. This is application example 2.

[0072] Example 3

[0073] A biodegradable bamboo-wood pulp composite material comprises the following raw materials in parts by weight:

[0074] Scandium: 2 parts;

[0075] Bamboo strips: 45 portions;

[0076] Water: 55 parts;

[0077] Coumarone resin: 3 parts;

[0078] Crosslinking agent: 10 parts;

[0079] Sodium hydroxide (NaOH): 5 parts;

[0080] Hydrophobic modifier: 2 parts;

[0081] Deinking agent: 1 part;

[0082] Sizing agent: alkenyl succinic anhydride (ASA): 1 part;

[0083] Antioxidant: 1 part;

[0084] Stearic acid: 1 part.

[0085] The bamboo strips, water, scandium, coumarone resin, crosslinking agent, caustic soda, hydrophobic modifier, deinking agent, sizing agent, antioxidant, and stearic acid in the formulation of Example 3 were mixed and pulped in a pulper. The resulting mixture was then heated to 230°C in a high-speed mixer and thoroughly stirred for 30 minutes to obtain the composite material. Its flexural strength and impact toughness were tested.

[0086] The application of a biodegradable bamboo-wood pulp composite material in the production of safety helmets specifically involves: feeding the composite material prepared in Example 3 above into a press to press the safety helmet into shape. This is Example 3.

[0087] Comparative Example 1

[0088] A biodegradable bamboo and wood pulp composite material safety helmet, comprising the following raw materials in parts by weight:

[0089] The specific formula is the same as in Example 1, except that stearic acid is not added.

[0090] The preparation method of the composite material in Comparative Example 1 is the same as that in Example 1.

[0091] Comparative Example 2

[0092] A biodegradable bamboo and wood pulp composite material safety helmet, comprising the following raw materials in parts by weight:

[0093] The specific formula is the same as in Example 1, except that scandium is not added.

[0094] The preparation method of the composite material in Comparative Example 2 is the same as that in Example 1.

[0095] Comparative Example 3

[0096] A biodegradable bamboo and wood pulp composite material safety helmet, comprising the following raw materials in parts by weight:

[0097] The specific formula is the same as in Example 1, except that no hydrophobic modifier is added.

[0098] The preparation method of the composite material in Comparative Example 3 is the same as that in Example 1.

[0099] The performance testing methods for the safety helmets in each embodiment and comparative example are as follows:

[0100] The composite materials for safety helmets were prepared according to the preparation methods of Examples 1-3 and Comparative Examples 1-3, and then tested according to the following testing methods. The test results are shown in Table 1.

[0101] Bending strength: Tested according to the test method in GB / T1449-2005;

[0102] Impact toughness (unnotched): Tested according to the test method in GB / T1451-2005.

[0103] After testing, the performance of the composite materials in Examples 1-3 did not meet the requirements, therefore no safety helmets were manufactured for testing. The safety helmets in Application Examples 1-3 were tested according to the test methods in GB2811-2019 "Head Protection Safety Helmets", and the test results were all qualified. The impact test data of the extreme high temperature resistance of the safety helmets in Application Examples 1-3 are shown in Table 1. In the impact test, it is specified that after pretreatment at an extreme high temperature of 150℃ for 1 hour, the force transmitted to the head mold should not exceed 4900N, and no fragments should fall off the helmet shell to be considered qualified.

[0104] Table 1. Detection results of Examples 1-3 and Comparative Examples 1-3

[0105] Bending strength (MPa) Impact toughness (KJ / ㎡) Impact force of the head mold (N) Example 1 175 117 Application Example 1 3955 Example 2 219 148 Application Example 2 2641 Example 3 248 165 Application Example 3 2172 Comparative Example 1 147 96 / / Comparative Example 2 109 64 / / Comparative Example 3 121 76 / /

[0106] The difference between Examples 1-3 and Comparative Example 1 is the absence of stearic acid. Test data shows that the optimal impact force that the head mold of this product can withstand is 2172 N, while the maximum flexural strength of the composite material can reach 248 MPa, and the impact toughness can reach 165 kJ / m. 2 The results are significantly greater than those of Comparative Example 1.

[0107] The difference between Comparative Example 2 and Comparative Example 1 is that stearic acid is added normally, but scandium is not added. The test data shows that the flexural strength and impact toughness of the composite material are significantly weakened, and the test data are much lower than those of Comparative Example 1 and the example.

[0108] The difference between Comparative Example 3 and Comparative Example 2 is that scandium is added normally, but no hydrophobic modifier is added. The test data shows that the flexural strength and impact toughness of the composite material are slightly increased, but all data are far lower than the test data of the Example.

[0109] Furthermore, the composite materials of Comparative Examples 1-3 all exhibited significantly lower performance than those of Example 1. This demonstrates that only by preparing composite materials according to the formulation of this invention, where the raw materials work synergistically, can a material with excellent performance be obtained for the manufacture of safety helmets.

[0110] The above description of the embodiments is intended to enable those skilled in the art to understand and use the invention. It will be apparent to those skilled in the art that various modifications can be made to these embodiments, and the general principles described herein can be applied to other embodiments without inventive effort. Therefore, the present invention is not limited to the above embodiments, and any improvements and modifications made by those skilled in the art based on the disclosure of the present invention without departing from the scope of the invention should be within the protection scope of the present invention.

Claims

1. A biodegradable bamboo-wood pulp composite material, characterized in that, The biodegradable bamboo and wood pulp composite material comprises the following raw materials in parts by weight: 40-45 parts bamboo or wood chips; 55-60 parts water; 1-2 parts scandium; 1-3 parts coumarone resin; 5-10 parts crosslinking agent; 2-5 parts caustic soda; 1-2 parts hydrophobic modifier; 1 part deinking agent; 1 part sizing agent; 1 part antioxidant; 1 part stearic acid.

2. The biodegradable bamboo-wood pulp composite material according to claim 1, characterized in that, The biodegradable bamboo and wood pulp composite material has a flexural strength ≥170MPa and an impact toughness ≥110KJ / ㎡.

3. The biodegradable bamboo-wood pulp composite material according to claim 1, characterized in that, The crosslinking agent is selected from any one or a mixture of phthalic anhydride, maleic anhydride and pyromellitic anhydride.

4. The biodegradable bamboo-wood pulp composite material according to claim 1, characterized in that, The hydrophobic modifier is: DL-171 silane coupling agent.

5. The biodegradable bamboo-wood pulp composite material according to claim 1, characterized in that, The deinking agent is FDMX-9801 liquid deinking agent.

6. The biodegradable bamboo-wood pulp composite material according to claim 1, characterized in that, The sizing agent is any one of rosin, alkyl ketene dimer (AKD), and alkenyl succinic anhydride (ASA).

7. A method for producing the biodegradable bamboo-wood pulp composite material according to any one of claims 1-6, characterized in that, The specific production method is as follows: Bamboo or wood chips, water, scandium, coumarone resin, crosslinking agent, caustic soda, hydrophobic modifier, deinking agent, sizing agent, antioxidant, and stearic acid are mixed in a pulping machine and pulped. The resulting mixture is then heated in a high-speed mixer and thoroughly stirred to obtain a composite material.

8. The production method according to claim 7, characterized in that, The heating temperature is above 200℃, and the stirring and mixing time is 30-40 minutes.

9. The application of the biodegradable bamboo-wood pulp composite material according to any one of claims 1-6 in the production of safety helmets, characterized in that, Specifically, the biodegradable bamboo and wood pulp composite material is fed into a molding machine and then pressed into a biodegradable bamboo and wood pulp composite material safety helmet.

10. The application according to claim 9, characterized in that, The safety helmets produced have a head impact force of ≤3960N.