A biodegradable mulch that can kill weeds

Abstract

The invention discloses a biodegradable mulch film capable of weeding. The mulch film is prepared from a first melt and a second melt according to multi-layer coextrusion and multi-layer coblowing ormulti-layer casting and biaxial stretching manners; the preparation process of the first melt is as follows: performing mixing extrusion on first resin, second resin, a compound stabilizer, an antiblocking agent and an interface compatibilizer in a screw extruder; and the preparation process of the second melt is as follows: firstly performing in-situ extrusion on weeding layer resin through a screw extruder, and directly performing mixing extrusion on the obtained resin, first resin, second resin, a chemical stabilizer, an interfacial compatibilizer and a composite inorganic salt buffering agent in a threaded rod. The biodegradable mulch film capable of weeding provided by the invention can make herbicide micro particles released in balance with degradation of the mulch film, and improvesa durable effect of a herbicide; and in addition, through a resin in-situ reaction in the processing process, the weather resistance and biological degradability of the mulch film are balanced, controlled degradation of the mulch film is realized, and the mulch film provided by the invention has obvious advantages compared with a traditional mulch film.

Description

technical field

[0001] The invention relates to the technical field of agricultural films, in particular to a biodegradable film capable of weeding. Background technique

[0002] According to reports, my country has become the country with the largest area covered by agricultural plastic film and the most types of crops covered. Although covering plastic film has increased farmers' income, the harm it brings is also obvious. Traditional plastic mulches are mostly high-molecular polymers made of polyethylene or polyvinyl chloride. The products are not easy to decompose under natural conditions, and cannot be degraded in the soil for hundreds of years. After years of cumulative use, the mulch film remains in the soil. Causing soil compaction, leading to crop yield decline and environmental pollution and other issues.

[0003] Currently available biodegradable materials mainly include polylactic acid (PLA), polyhydroxy fatty acid (PHAs), polybutylene succinate (PBS), poly(but...