The preparation of wood-plastic composite materials was first prepared by compounding wood powder and thermosetting resin phenolic resin. Later, in the 1970s and 1980s, wood powder and polypropylene were used to make wood-plastic composite materials, which were used in the inner lining of Ford cars due to their advantages of low price, light weight and high strength. develop. Many researchers have tried to use various plant fibers such as bamboo, wheat straw, jute and even coconut shell to compound with thermoplastic resins and improve the properties of the composite materials.

However, due to the significant difference between the hydrophobicity of plastics and the hydrophilicity of plant fibers, the resulting interface incompatibility has seriously affected the uniform combination of raw materials, and has had a negative impact on the mechanical strength and durability of products. seriously affected. Therefore, solving the interfacial compatibility problem between plant fibers and plastics has always been the core focus of attention in the field of wood-plastic composites manufacturing. Biochar is a kind of highly aromatic and insoluble solid substance produced by pyrolysis and carbonization of biomass materials in an anoxic environment. In recent years, biochar has been used as a soil conditioner and a slow-release carrier for chemicals due to its excellent adsorption properties, and it has been used in agriculture to a certain extent. Biochar also has excellent rigidity and strong surface activity, which shows the potential of biochar in strengthening polymers to prepare composite materials. The use of cheap biochar raw materials to manufacture new composite materials with reasonable cost and unique properties has broad development and application prospects, and also provides a new direction for the utilization of biochar.

In view of the above-mentioned problems, there is a patent to provide a bamboo charcoal fiber-polyethylene composite floor preparation process. The present invention can make the selectivity of ultrafine bamboo charcoal ions in the high-density polyethylene phase by mixing in the next step under the condition of an external magnetic field. distribution, forming a network structure of ultra-fine bamboo charcoal particles, exerting the high-strength and high-modulus reinforcement of ultra-fine bamboo charcoal, and the ultra-fine bamboo charcoal particles can undergo synergistic reinforcement, which further improves the mechanical properties and thermal properties of the composite material.

 

Technical solutions:

Bamboo charcoal fiber-polyethylene composite floor preparation process, comprises the following steps:

Step 1: Send ultrafine bamboo charcoal, high-density polyethylene, and adjuvant into a high-speed mixer and mix to obtain a mixture;

Step 2: feeding the mixture into a screw extruder, and performing melt extrusion under the condition of applying a constant magnetic field to obtain a composite material;

Step 3: feeding the composite material into an injection molding machine for melting, and then cooling and shaping in the mold to obtain a laminated floor;

Wherein, the mixing agent is a coupling agent containing metal ions with magnetic response. In order to improve the interfacial compatibility of ultra-fine bamboo charcoal and high-density polyethylene, the technical means of combining a magnetically responsive coupling agent and applying a constant magnetic field is used.

The principle of adopting the above technical scheme includes: under the condition of external constant magnetic field, the carbon atoms in the ultra-fine bamboo charcoal are bonded to form a ring structure, and the induced magnetic moment is generated under the action of the magnetic field, and the induced magnetic moment rotates under the action of the external magnetic field to finally The charcoal layer of ultra-fine bamboo charcoal is oriented in the direction perpendicular to the magnetic field; similarly, high-density polyethylene is a non-polar material, which generates an induced dipole moment under the action of a magnetic field in a molten state, so that the spherulites are oriented along the direction of the magnetic field. Elongated, tending to directional crystallization, under the pull of an external magnetic field, the front of the crystallization region forms a “whisker” additional crystallization region, and makes the radial lamellae grow from twisted to straightened; finally, the metal ion coupling agent acts on the magnetic field Arranged in the direction parallel to the crystal axis with the largest magnetic susceptibility. In this way, when the ultrafine bamboo charcoal, metal ion coupling agent, and high-density polyethylene are melt-mixed, under the action of a magnetic field, the oriented distribution of ultrafine bamboo charcoal is more likely to enter the same directional crystallized high-density polyethylene, so that the high-density polyethylene and The gap between the ultrafine bamboo charcoal is reduced, and the interfacial bonding force between the high-density polyethylene and the ultrafine bamboo charcoal is strengthened under the series connection of the metal ion coupling agent, which plays the role of “stitching” the cross-linked network, and finally makes High-density polyethylene has a good coating effect on ultrafine bamboo charcoal, which greatly improves the mechanical properties of the composite material.

Other News