48 documents found, page 1 of 5
Development of multi-scale carbon nanofiber and nanotube-based cementitious com...
Parveen, Shama; Vilela, Bruno; Lagido, Olinda; Rana, Sohel; Fangueiro, RaúlIn this work, multi-scale cementitious composites containing short carbon fibers (CFs) and carbon nanofibers (CNFs)/multi-walled carbon nanotubes (MWCNTs) were studied for their tensile stress sensing properties. CF-based composites were prepared by mixing 0.25, 0.5 and 0.75 wt.% CFs (of cement) with water using magnetic stirring and Pluronic F-127 surfactant and adding the mixture to the cement paste. In multi...
Micro-structure and mechanical properties of microcrystalline cellulose-sisal f...
Souza Filho, Aloysio; Parveen, Shama; Rana, Sohel; Vanderlei, Romel; Fangueiro, RaúlThis paper reports new hierarchical cementitious composites developed using microcrystalline cellulose (MCC), sisal fibers and cetyltrimethylammonium bromide (CTAB) as the dispersing agent. MCC was dispersed in water without and with CTAB at different concentrations using ultrasonication and the optimum CTAB concentration for achieving homogeneous and stable MCC suspensions was found to be 40%. Hierarchical com...
Accelerated weathering of textile waste nonwovens used as sustainable agricultu...
Abidi, Houcine; Rana, Sohel; Chaouch, Walid; Azouz, Bechir; Aissa, Imed Ben; Hassen, Mohamed Ben; Fangueiro, RaúlThe removal of agriculture residual plastic films is nowadays a big concern for all environmentalists. Several ecological alternatives were developed for more sustainable products and cleaner production. In this work, the effect of three months of exposure under accelerated weathering conditions (ultraviolet light, moisture, and heat) on the properties of two textile waste nonwovens as a sustainable alternative...
Improvement of mechanical behavior and microstructure of microcrystalline cellu...
Souza Filho, Aloysio Gomes de; Parveen, Shama; Rana, Sohel; Vanderlei, Romel; Fangueiro, RaúlThis work reports the development of multiscale cementitious composites containing sisal fibres and microcrystalline cellulose (MCC), previously dispersed by ultrasonication and cetyltrimethylammonium bromide (CTAB), as the novel dispersing agent. The mechanical tests performed allowed to identify significant improvement in the mechanical properties, hydration degree, and microstructure.
Effect of dispersion parameters on the efficacy of micro crystalline cellulose ...
Filho, Aloysio; Parveen, Shama; Rana, Sohel; Vanderlei, Romel; Fangueiro, RaúlThis work compares the influence of Pluronic®F-127 and CTAB (cetyltrimethylammonium bromide) as surfactants on the dispersion of microcrystalline cellulose (MCC) for developing cementitious composites. The characterization of MCC dispersion quality was performed through visual inspection, UV-Vis and optical microscopy. The results showed significant improvement in the homogeneity of MCC dispersion using both Pl...
Hierarchical cementitious composites developed by sisal fibers and micro crysta...
Filho, Aloysio; Parveen, Shama; Rana, Sohel; Vanderlei, Romel; Fangueiro, RaúlThe present research investigated the influence of multi-scale reinforcements [sisal fibers (Agave Sisalana) and microcrystalline cellulose (MCC)] on the mechanical properties of cementitious composites. Aqueous dispersions of MCC were prepared by using two different surfactants namely
Mechanical performance of composite materials developed using novel re-entrant ...
Magalhães, Rui Miguel Pires; Rana, Sohel; Fangueiro, Raúl; Gonçalves, Clara Catarina Pereira; Nunes, J. P.; Dias, Gustavo R.In this research, novel high performance auxetic fabric structures (and composites) were produced using the flat knitting technology and their auxetic and tensile behaviors were characterized. The fabrics were produced using two types of high performance fibres (para-aramid and polyamide) and by varying the structural and process parameters.Subsequently, the produced fabrics were impregnated with an epoxy resin...
Novel multi-scale cementitious composites developed using Microcrystalline Cell...
de Souza Filho, Aloysio Gomes; Parveen, Shama; Rana, Sohel; Vanderlei, Romel Dias; Fangueiro, RaúlIn this work, multi-scale cementitious composites were developed using microcrystalline cellulose (MCC) and sisal fibers as reinforcements. Mechanical performance of plain mortar and reinforced mortar samples containing MCC (0.1, 0.2, 0.4 and 0.6%) and 0.50% sisal fibers (with respect to cement weight) was investigated. The experimental work was carried out by dispersing MCC in water with the help of a non-ioni...
Development and characterization of high performance auxetic fabrics produced u...
Magalhães, Rui; Gonçalves, Clara; Rana, Sohel; Fangueiro, Raúl; Nunes, Pedro; Dias, GustavoThis paper reports an overview of auxetic fibrous structures with negative Poisson´s ratio (NPR). These type of behaviour have a vast potential for applications in personal protection due to their high energy absorption and excellent impact resistance. The aim of this study, is to evaluate the behaviour of purl structure design, produced through weft knitting technology using high performance polyamide (PA) fib...
Ultrasonic dispersion of micro crystalline cellulose for developing cementitiou...
Parveen, Shama; Rana, Sohel; Ferreira, Simão; Filho, Aloysio; Fangueiro, RaúlThis paper reports the first attempt to utilize ultrasonication energy for homogeneously dispersing microcrystalline cellulose (MCC) to develop MCC reinforced cementitious composites. Aqueous suspensions of MCC (1.0–5.0 wt.% with respect to water) were prepared using ultrasonication treatment and the suspensions were then added to the cement mortar mixes. The aqueous suspensions were characterized using optical...