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CN-121975284-A - Degradable green building template material and preparation and recovery process thereof

CN121975284ACN 121975284 ACN121975284 ACN 121975284ACN-121975284-A

Abstract

The invention discloses a degradable green building template material and a preparation and recovery process thereof, and relates to the technical field of building materials, wherein the material is prepared from the following raw materials, by weight, 100 parts of matrix resin which is polycaprolactone or a blend of the polycaprolactone and polybutylene succinate, 20-40 parts of natural plant fibers with the thickness of 3-15mm, 0.5-3 parts of an interface modifier, 5-15 parts of a toughening agent and 1-5 parts of a nucleating agent. The biodegradation rate of the material is more than 90% in 180 days under the standard soil composting condition. The preparation process includes fiber pretreatment, material premixing, melt blending granulation and template molding. The recovery process provides two paths, namely physical recovery and remanufacturing, mixing the fragments with the newly added resin and the modifier for reprocessing, and biological degradation and component recycling, mixing the fragments with organic waste for controlled composting, and taking the product as a soil conditioner. The material of the invention is green and degradable, and is matched with a complete recycling scheme.

Inventors

  • Ding Shunfang

Assignees

  • 丁顺芳

Dates

Publication Date
20260505
Application Date
20260119

Claims (10)

  1. 1. A degradable green building template material and a preparation and recovery process thereof are characterized by comprising, by weight, 100 parts of matrix resin, 20-40 parts of natural plant fibers with the length of 3-15mm, 0.5-3 parts of interface modifier, 5-15 parts of flexibilizer and 1-5 parts of nucleating agent, wherein the matrix resin is polycaprolactone or a blend of polycaprolactone and polybutylene succinate, and the biodegradation rate of the material is more than 90% in 180 days under standard soil composting conditions.
  2. 2. The degradable green building template material and the preparation and recovery process thereof according to claim 1, wherein the blending weight ratio of polycaprolactone to polybutylene succinate is (70-80): (30-20).
  3. 3. The degradable green building template material and the preparation and recovery process thereof according to claim 1 are characterized in that the natural plant fiber is at least one selected from bamboo fiber, fibrilia and straw fiber, the interface modifier is silane coupling agent or maleic anhydride grafted polycaprolactone, the toughening agent is bio-based polyester polyurethane elastomer, and the nucleating agent is organic montmorillonite or talcum powder.
  4. 4. A degradable green building template material and process for preparing and recycling same according to any one of claims 1-3, characterized in that it comprises the steps of: (1) Fiber pretreatment, namely drying natural plant fibers, treating the natural plant fibers with an interface modifier solution, and then drying the natural plant fibers for later use; (2) Premixing raw materials, namely mixing matrix resin, a toughening agent, a nucleating agent and other auxiliary agents to obtain a premix; (3) Melt blending and granulating, namely, carrying out melt extrusion and granulating on the premix obtained in the step (2) and the plant fiber treated in the step (1) together to obtain composite granules; (4) And (3) template molding, namely carrying out hot press molding or extrusion molding on the composite granules to obtain the building template plate.
  5. 5. The degradable green building template material and the preparation and recycling process thereof according to claim 4, wherein in the step (3), the melt extrusion is performed in a twin screw extruder, and the extrusion temperature is set to 120-160 ℃ from a feed inlet to a machine head.
  6. 6. The degradable green building template material and the preparation and recovery process thereof according to claim 4, wherein in the step (4), the hot press molding process conditions are that the temperature is 160-170 ℃, the pressure is 5-10 MPa, and the pressure is maintained and cooled after the preheating time is 5-8 minutes.
  7. 7. A degradable green building template material and a preparation and recovery process thereof as claimed in any one of claims 1-3, wherein the physical recovery and remanufacturing route is adopted for the waste template, and the method comprises the steps of mixing clean and crushed template fragments with a newly added interface modifier and matrix resin, and performing melt blending and reprocessing to prepare regenerated granules or products.
  8. 8. The degradable green building template material and the preparation and recovery process thereof according to claim 7, wherein the addition amount of the newly added interface modifier is 1-3% of the weight of template fragments, the addition amount of the newly added matrix resin is 3-8% of the weight of fragments, and the melting temperature during reprocessing is 5-10 ℃ lower than the original preparation temperature.
  9. 9. A degradable green building template material and a preparation and recovery process thereof according to any one of claims 1-3, wherein the waste template adopts a biodegradation and component recycling path, and comprises the steps of mixing crushed template fragments with organic wastes, performing controllable high-temperature aerobic composting to enable the material to be completely biodegraded, and taking the obtained composting product as a soil conditioner.
  10. 10. The degradable green building template material and the preparation and recovery process thereof according to claim 9, wherein the mixing volume ratio of the template fragments to the organic waste is 1 (3-5), the composting process is controlled to control the carbon nitrogen ratio to be 1 (25-30), the water content is 50-60%, and the temperature of the composting is maintained at 50-60 ℃.

Description

Degradable green building template material and preparation and recovery process thereof Technical Field The invention relates to the technical field of building materials, in particular to a degradable green building template material and a preparation and recovery process thereof. Background In the field of constructional engineering, templates are key temporary supporting structures for forming concrete structures, and the requirements are huge. For a long time, building templates mainly adopt materials such as wood, steel, bamboo plywood and the like. The wood template has the advantages of convenient processing, limited turnover times, low recycling rate, high durability and turnover times of the steel template, but has the problems of heavy weight, high cost, easy corrosion, poor field processing adaptability and the like. In order to balance performance, cost and resource consumption, a laminated wood form and a bamboo plywood made of paper or wood veneers impregnated with thermosetting resins such as phenolic resin and urea resin have been widely used. However, the template has the risk of formaldehyde release in the production and use processes, the waste is difficult to effectively degrade, and the template is usually treated in a landfill or incineration mode, so that not only occupies land resources, but also toxic and harmful gas can be generated due to improper incineration, and secondary environmental pollution is caused. Therefore, development of a green building template material which has good use performance, is environment-friendly and can be recycled or naturally consumed has become an important subject to be solved in sustainable development of the building industry. In recent years, with the increasing strictness of environmental regulations and the advancement of 'double carbon' targets, biodegradable polymer materials have shown great potential in replacing traditional petroleum-based plastics. Polycaprolactone (PCL) and polybutylene succinate (PBS) are two representative classes of biodegradable polyesters. PCL has good flexibility, processing compatibility and low-temperature biodegradability, but has a low melting point (about 60 ℃), and the mechanical strength, particularly the rigidity and the heat resistance are insufficient to meet the requirements of bearing and dimensional stability of the formwork in the concrete pouring process. PBS has a higher melting point (about 114 ℃) and better mechanical strength, but relatively poorer toughness and slower degradation rate than PCL. The two materials are blended, so that the advantages are complementary in theory, a material system with more balanced comprehensive performance is obtained, but the problem of poor interface compatibility often exists in simple physical blending, and the final performance is influenced. Natural plant fibers (such as bamboo fibers, hemp fibers, straw, etc.) are widely introduced as reinforcing phases into degradable polymeric matrices in order to increase the rigidity of the materials and reduce the cost of the raw materials while imparting more natural properties thereto. The fibers have the advantages of wide sources, reproducibility, biodegradability, high specific strength and specific modulus and the like. However, natural plant fibers have the problems of high hydroxyl group content, strong hydrophilicity and obvious interface incompatibility between the natural plant fibers and a nonpolar or polar weak degradable polyester matrix, so that the stress transmission efficiency is low, the mechanical properties of the composite material are reduced, and particularly the impact toughness is seriously damaged. Meanwhile, the fiber is easy to damage due to high temperature and high shear in the processing process, the length retention rate is low, and the reinforcing effect is further weakened. In addition, although the addition of plant fibers can increase the rigidity of the material, the brittleness of the material is often increased, and the impact and bending load possibly born by the building template during construction is difficult to meet. In addition to producing high performance materials, the manner in which the end of life is treated also determines their "green" nature. At present, the main terminal treatment thought of the degradable composite material mainly comprises two steps of firstly, physical recovery and remanufacturing, namely, remanufacturing the degradable composite material into a product through melting and reprocessing, so as to realize resource circulation, but the problem of performance degradation of the material after multiple processing due to thermal degradation and interface degradation is solved, and secondly, biodegradable composting is carried out, so that the degradable composite material returns to nature under specific conditions. However, not all nominally "degradable" materials can degrade rapidly and completely under natural or industrial composting condition