CN-224205837-U - Ultraviolet-resistant PBAT composite degradable agricultural mulching film

Abstract

The utility model relates to the field of agricultural mulching films, and mainly aims at the problem of insufficient ultraviolet shielding effect of the existing PBAT agricultural mulching film, and provides an ultraviolet-resistant PBAT composite degradable agricultural mulching film, which is characterized by comprising a front packaging layer 1 serving as a light-receiving surface, an ultraviolet shielding layer 2 and a back packaging layer 3 serving as a soil contact surface which are sequentially stacked, wherein the ultraviolet shielding layer 2 comprises a structure body formed by compositing PBAT and a nanoscale ultraviolet shielding material, the nanoscale ultraviolet shielding material is in a micro-nano composite structure in which a nano sheet layer and a micro sheet layer are uniformly mixed in the ultraviolet shielding layer 2, and the nano composite structure is arranged in an oriented manner in a PBAT matrix to form a brick mud structure. The PBAT degradable composite mulch film can effectively ensure visible light transmission and excellent mechanical properties, reduces ageing and degradation of the mulch film caused by ultraviolet radiation, and is expected to be used in agricultural fields, in particular in agricultural fields which particularly need ultraviolet shielding.

Inventors

• YU SHUHONG
• LI DEHAN
• HAN ZIMENG
• GUAN QINGFANG

Assignees

• 中国科学技术大学

Dates

Publication Date

20260508

Application Date

20241125

Claims (4)

1. 1. An ultraviolet-resistant PBAT composite degradable agricultural mulching film is characterized by comprising a front packaging layer (1) serving as a light-receiving surface, an ultraviolet shielding layer (2) and a back packaging layer (3) serving as a soil-contacting surface which are sequentially stacked, wherein phlogopite in the ultraviolet shielding layer (2) is of a micro-nano composite structure formed by uniformly compositing a nano sheet layer and a micro sheet layer, the phlogopite is arranged in a PBAT matrix of the ultraviolet shielding layer (2) in an orientation manner to form a brick mud structure, the diameter of the micro sheet layer is 20-50 mu m, and the diameter of the nano sheet layer is 100-500 nm.
2. 2. The ultraviolet-resistant PBAT composite degradable agricultural mulching film according to claim 1, wherein the thickness of the front packaging layer (1) is 10-20 μm, the thickness of the ultraviolet shielding layer (2) is 5-10 μm, and the thickness of the back packaging layer (3) is 10-20 μm.
3. 3. The ultraviolet-resistant PBAT composite degradable agricultural mulching film according to claim 1, wherein the front packaging layer (1), the ultraviolet shielding layer (2) and the back packaging layer (3) are directly laminated together.
4. 4. The ultraviolet-resistant PBAT composite degradable agricultural mulching film as claimed in claim 3, wherein no adhesive layer exists among the front packaging layer (1), the ultraviolet shielding layer (2) and the back packaging layer (3).

Description

Ultraviolet-resistant PBAT composite degradable agricultural mulching film Technical Field The utility model relates to the field of agricultural mulching films, in particular to an ultraviolet-resistant PBAT composite degradable agricultural mulching film. Background Polybutylene adipate/terephthalate (PBAT), which is a thermoplastic biodegradable plastic, is a copolymer of butylene adipate and butylene terephthalate. It has biodegradability, can be degraded into water, carbon dioxide and organic matters by microorganisms in natural environment, and reduces environmental pollution. The PBAT has good processability, is suitable for being used for manufacturing packaging materials, articles for daily use, medical appliances, agricultural mulching films and the like, and has important environmental protection and economic significance. Conventional agricultural mulch films are typically made of plastics such as polyethylene, but these plastic films may present environmental problems after use, such as difficulty in degradation and impact on the soil ecosystem. The agricultural mulching film prepared based on the PBAT can well control soil humidity, temperature and weed growth, and meanwhile, the PBAT has good biodegradability, can be decomposed into harmless substances by microorganisms after being used, and cannot cause long-term influence on soil and environment, so that the yield and quality of crops are improved. But the PBAT has the defect of insufficient ultraviolet shielding effect, so that the PBAT agricultural mulching film is degraded and aged under the irradiation of ultraviolet rays, the function of good service life of the agricultural mulching film is affected, and the wide application of the PBAT in the mulching film field is hindered to a certain extent. Currently, the ultraviolet screening strategy for improving PBAT mulch is mainly by adding ultraviolet absorbers to the PBAT pellets. Ultraviolet absorbers are mainly classified into two major classes, namely organic absorbers and inorganic absorbers, the organic absorbers commonly comprise phenols, styrenes and the like, but the organic absorbers have certain toxicity and can cause certain damage to organisms and natural environments when in use and after being abandoned. Inorganic absorbers are a class of inorganic substances, such as metal oxides, metal complexes and the like, and typically represent materials including zinc oxide, titanium oxide and the like, but inorganic ultraviolet absorbers have the defects of narrow absorption wavelength, limited light stability, difficult dispersion and the like, and certain mechanical defects can be introduced when the inorganic ultraviolet absorbers are added into the PBAT mulch film. In addition, a certain color exists in part of the ultraviolet absorbent, and when the ultraviolet absorbent is added into the PBAT mulch film, the transmission of the film to visible light can be reduced, and the color and the use effect of the mulch film are affected. In summary, how to realize that the PBAT agricultural mulching film has an excellent ultraviolet shielding effect in terms of structural improvement while not affecting the mechanical strength, the degradability and the visible light transmittance of the PBAT agricultural mulching film is a problem to be solved in the field. Disclosure of utility model The utility model mainly aims at the problem of insufficient ultraviolet shielding effect of the existing PBAT-based agricultural mulching film, structurally designs and provides the ultraviolet-resistant PBAT composite degradable agricultural mulching film, which not only can keep the light transmittance and mechanical property of the mulching film, but also has excellent ultraviolet shielding effect, can effectively block ultraviolet rays, delay the aging and degradation of the mulching film and prolong the service life of the mulching film. The utility model adopts the solution scheme that the ultraviolet-resistant PBAT composite degradable agricultural mulching film comprises a front packaging layer (a light-receiving surface), an ultraviolet shielding layer and a back packaging layer (a soil contact surface) which are sequentially stacked. The front packaging layer and the back packaging layer are composed of single PBAT films, and the ultraviolet shielding layer is composed of PBAT and nanoscale ultraviolet shielding materials in a compounding mode. The nano ultraviolet shielding material is uniformly compounded and oriented in the PBAT matrix to form a brick mud structure, so that the layer has an excellent ultraviolet shielding effect. After the plastic film is combined with the front and back packaging layers, the good ultraviolet shielding effect of the plastic film can obviously improve the efficiency and quality of agricultural production while effectively ensuring the transmission of visible light and excellent mechanical properties. The brick mud structure is characterized in that the nano