Greenhouse PE and EVA agricultural films are inherently hydrophobic inert polyolefin materials with high surface tension. Water vapor inside greenhouses readily condenses into fine mist droplets and water beads adhering to the film surface, resulting in light obstruction, water dripping, and diseases triggered by excessive humidity. With ultra-low surface activity of perfluorinated/short fluorocarbon chains, high thermal stability, and oriented interfacial arrangement properties, fluorocarbon surfactants fundamentally resolve the challenges of drip retention, anti-fog performance, and weather resistance of agricultural films. Their core mechanisms fall into three categories:
Fluorocarbon surfactants are the additives with the highest known surface activity. They can reduce the surface tension of agricultural films to below 20 mN/m, far lower than that of pure water. During film forming, these additives migrate directionally to both inner and outer surfaces of the film and form a uniform hydrophilic interfacial layer. This prevents condensed water vapor in greenhouses from forming spherical water beads; instead, the moisture rapidly spreads into a continuous water film that slides down along the film wall. This completely eliminates dripping and clinging water beads and delivers sustained drip flow performance.
Conventional hydrocarbon and organosilicon additives only provide short-term drip flow and fail to eliminate aerosol fog inside greenhouses. Fluorocarbon additives construct dense and ordered molecular thin films at the three-phase interface of gas, film and water, disrupting the conditions for suspension and aggregation of fog droplets. Tiny fog droplets rapidly coalesce and settle, while the reformation of water vapor fog within the greenhouse is inhibited. This significantly boosts the light transmittance of greenhouse films and addresses the key pain points of hazy conditions and insufficient light in greenhouses.
Fluorocarbon molecular structures feature extremely high bond energy, offering far superior resistance to high temperatures, weathering and precipitation compared with traditional additives. They do not decompose or lose efficacy under the high-temperature environment (180–220℃) of agricultural film blow molding processing. Moreover, their molecular migration rate is uniform and slow, avoiding massive precipitation and loss within a short period as seen with ordinary additives. This fundamentally solves the problems of degraded drip flow and anti-fog performance as well as whitening and aging of film surfaces in the later service stage of agricultural films.
