Recycled jute fiber is proposed for the purpose of manufacturing textile reinforcements for composite materials for building applications in combination with a polymer matrix. This fiber is biomass-based. It is hydrophilic and does not resist fungal attack. This limits its use in durable products, such as those made with synthetic fibers. Surface treatments were thus developed to improve the hydrophobicity of the jute fibers. Work also involved improving its fire resistance.
In order to preserve the green aspect of the jute nonwoven, the choice focused on non-toxic treatments. These treatments include the use of fatty acids, ZnO and TiO2 nanoparticles, and fire retardants based on phosphorus and nitrogen compounds. The assessment of these fiber surface treatments was carried out by measuring the TR (time at which a drop of water changes shape) and WCA (contact angle formed by a drop of water deposited on the textile surface) for the hydrophobic treatment, and a flammability test for the fire retardant treatment. The impact of these treatments on the thermal, mechanical, and morphological properties of the jute fiber and nonwoven has also been studied.
Direct treatment with fatty acids slightly improved the nonwoven hydrophobicity, independently of the thermal bonding mode used. The hydrophobicity reached after an optimization was conducted using experimental designs, was comparable to that of the reference synthetic nonwoven in terms of WCA, but remained significantly lower in terms of TR.
Three methods have been investigated to create a ZnO-based nanoscale roughness on the jute fiber surface in order to increase its hydrophobicity after treatment with the fatty acid. The first method involves the synthesis of ZnO particles with a binder. The second one comprises a seeding step and a growth step which is applied by sonication. The third method is a hydrothermal process. The geometric parameters of the ZnO nanorods formed by the hydrothermal process were determined using a model based on the data provided by the TGA, MEB, and MCBL.
As an alternative strategy, the synthesis of TiO2 particles on the jute fiber surface was carried out by a sol-gel process according to two techniques. The first technique involves only one step. The second comprises two steps and requires the use of an acid. The coating of the jute nonwoven with TiO2 particles increased its affinity for fatty acids; its hydrophobicity was also improved in terms of TR. The time treatment was drastically reduced by the use of a padder without negatively affecting the nonwoven performance. An analysis of the jute nonwoven behaviour was also made as a result of heat and UV aging.
The addition of 4% of TiO2 in a MDPA solution applied before the hydrophobic treatment with TiO2/AS made the jute nonwoven fire retardant and moderately hydrophobic. A reduction of about 50% in mechanical performance was observed.
This work allowed the development of a series of hydrophobic and/or flame retardant treatment for recycled jute nonwovens. They offer a portfolio of choices depending the application requirements.
| Date | 21 Feb 2017 |
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| Original language | French |
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| Awarding Institution | - École de technologie supérieure
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| Supervisor | Martine Dubé (Supervisor) & Éric David (Co-supervisor) |
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Arfaoui, M. A. (Author),
Dubé (Supervisor) &
David (Co-supervisor),
21 Feb 2017Student thesis: Doctoral thesis › Doctorate in Engineering: Engineering