Fibers & Textiles Figure
Fibers & Textiles Figure 5: Bio-monofilaments from the compound Sea212 Figure 1: Mechanical strength in relation to diameter strength (N) 160 140 120 100 80 60 40 20 0 0,1 0,2 0,3 0,4 0,5 0,6 diameter (mm) Figure 2: Marine ageing of the monofilaments after one year of immersion. 0,7 0,8 0,9 A new generation of compostable monofilament for a wide range of applications SeaBird, based in Brittany, France, is a company that engages in the research, development and production of bioplastic materials. Since its founding in 2011, the company has focused on reducing the impact of conventional plastics in the marine environment by evolving sustainable waste management solutions. Seabird produces compostable bioplastic formulations enhanced with fillers and additives that are able to meet the specifications and process constraints of their industrial partners while retaining their environmentally-friendly nature (no volatile organic compounds (VOCs), toxic additives and others, end-of-life valuation). In 2017, the company validated the industrial production of monofilaments based on one of these compounds, called Sea212 ® . Developed for use on an extrusion spinning process line, the compound is a blend of different bio-polyesters and bio-additives. The various ingredients are expertly combined to meet all process specifications and provide the required physical properties, while at the same time complying both with the European composting standard EN13432 / EN 14995 and the food contact standard. The monofilaments are used in many products developed by Seabird and some industrial partners. Special consideration was given to the homogeneity and rheological stability of the blend in order to guarantee the compound’s processability. The compound can be processed at 170 °C, which is lower than the temperature used for most conventional plastics. Properties of the monofilament A range of monofilament diameters (from 0.2 mm to 1.0 mm) were developed, targeted at a wide array of applications. Figure 1 shows the mechanical strength of the monofilament in relation to the diameter. The mechanical tests were performed according to standard EN ISO 2062. Although a monofilament tenacity of 2.4 cN/dtex was found for a monofilament with a diameter of 0.65 mm - a quarter less than certain conventional monofilaments - it is still sufficient for many applications. 18 bioplastics MAGAZINE [05/19] Vol. 14
Fibers & Textiles The monofilament boasts numerous interesting properties. The material remains stable up to 80 °C; it is lighter than PET, easily dyable due to its natural white color, easy to tie and is resistant to common solvents such as acetone, ethanol and white spirit. Marine ageing The compound was developed for, among other things, marine applications, and designed to have a useful life of five years with no significant degradation of the properties. The objective, therefore is to produce compostable products that are economically viable; i.e. products with a useful life that is similar in length to conventional products, to avoid having to invest earlier in new equipment because of a shorter lifespan. To assess the lifespan of the monofilaments, ageing experiments have been carried out at Lorient’s harbor since 2017. Figure 2 shows scanning electron microscope (SEM) images of a monofilament after 12 months of marine immersion. These analyses demonstrated a surface degradation of the monofilament, but the mechanical properties remained stable. A compostable geotextile A new generation of industrially compostable geotextile fences have been under development with an industrial partner since 2017 (Figure 3). These fences protect dunes from wind erosion and because they are sometimes entirely covered by sand, they are not systematically cleared away after use. In order to develop a more ecofriendly product, biodegradation studies on this woven geotextile have been carried out on a beach since January 2019. A compostable beach access and soil protect carpet is also being developed. Compostable trammel fishing nets It was recently reported that a 12m French gillnetter (fishing boat) produces about 8000 kg of waste per year, most of which takes the form of fishing nets. In order to find an alternative end-of-life solution to landfill or incineration, a compostable trammel fishing net prototype was developed in 2019. A trammel net is composed of three layers: the two outside layers are made from a 0.60 mm monofilament and the inside layer (fishing layer) is produced from a 0.33 mm monofilament. These trials allowed the prototypes to be assessed for flaws in order to improve the net quality. Figure 4 shows a piece of the produced fishing layer. At the moment, Seabird’s R&D office is working on the enhancement of some of the properties of the monofilaments, such as the abrasion resistance. Net production and fishing trials in real conditions are scheduled for 2020. Others perspective products The technical potential of Sea212 compound and its monofilaments improves with each challenge encountered in the projects. Seabird works with other partners to develop ropes, mussel gillnets and oyster pockets. Also, Seabird is reaching out to other application sectors such as household, packaging and medical textiles. www.seabird.fr By: Vincent Mathel Bioplastic engineer and project manager. ICCI SEA (“Seabird”) Lorient, France. Figure 3: Fence to protect the dunes Figure 4: Piece of trammel fishing net from the bio-monofilaments bioplastics MAGAZINE [05/19] Vol. 14 19
