Utilization Of Flax And Hemp Fibers In Nonwoven Weed Suppression Geotextiles

It is claimed that global economic loss due to weeds is more than one hundred billion dollars. Synthetic geotextiles have long been used to suppress weeds, but they are manmade high molecular materials, not biodegradable, and it will cause air and water pollution during production. To solve this problem, natural fibers have been utilized to produce weed suppression geotextiles, but few studies have been conducted to make weed suppression geotextiles using natural fibers such as flax and hemp fibers. This research is focused on utilization of flax and help fibers in nonwoven weed suppression geotextiles. These fabrics have been compared with currently available weed control fabrics (made from polypropylene and wood fiber) to determine their suitability for this particular purpose. The resulting fabrics were evaluated for basis weight, thickness, tensile properties, light, and water transmission.The main results are listed as follows:1. The basis weight, thickness properties have been tested in this research to compare the properties of flax and hemp nonwoven geotextiles and that of the commercial polypropylene and wood fiber weed suppression materials. The results show that the flax and hemp geotextiles are with thickness of2.44mm-4.33mm,237-318g/m2. They are thicker and heavier than polypropylene and wood fiber weed suppression materials. But studies showed that fabric basis weight and thickness are not well correlated with ability to suppress weeds, so flax and hemp fibers have the potential to make weed suppression geotextiles.2. Flax and hemp fibers have superior moisture regain values than that of polypropylene fibers, which will lead to great moisture absorbency (9.8g-26.3g) to speed up degradation of the weeds. Flax and hemp fiber geotextiles have similar water penetration property as that of polypropylene and wood fiber weed suppression textiles, which can make sure the growth of the desired plants.3. Light blockage is a key factor for weed suppression. Good weed suppression geotextiles will block the sunlight from going through the material to avoid photosynthesis so that weed cannot grow. The flax and hemp geotextiles have very high light blockage rate:96.5%-99.5%, far better than that of polyethylene weed suppression materials (79.4%), which proved that they can suppress weed.4. The tensile strength of flax and hem fiber geotextiles is0.26-1.18kgf/cm2, tensile toughness is4.0-31.7kgf/cm2while the initial modulus is1.1-5.3kgf/cm2. Even though flax and hem fiber geogextiles have lower tensile properties than that of polypropylene and wood fiber weed suppression materials, it still has the potential of producing as weed suppression geogextiles with proper tensile improvement.5. Between the flax and hemp fibers, the hemp fibers that were utilized in this research have less impurities, better moisture absorbency and light blockage, which indicates better suitability for weed suppression application.Overall, the flax and hemp geotextile fabrics have the potential to be used as weed suppression fabric with suitable modifications like increasing the strength to achieve easier installation. This research also provides an alternative disposal method for pre-processing flax and hemp fibers, which has both ecological and economic benefits.