Electrospinning of recycled PET to generate tough mesomorphic fibre membranes for smoke filtration

Abstract

Tough fibrous membranes for smoke filtration have been developed from recycled polyethylene terephthalate (PET) bottles by solution electrospinning. The fibre thicknesses were controlled from 0.4 to 4.3 mm by adjustment of the spinning conditions. The highest fibre strength and toughness were obtained for fibres with an average diameter of 1.0 mm, 62.5 MPa and 65.8 MJ m À3 , respectively. The Xray diffraction (XRD) patterns of the fibres showed a skewed amorphous halo, whereas the differential scanning calorimetry (DSC) results revealed an apparent crystallinity of 6-8% for the 0.4 and 1 mm fibres and 0.2% crystallinity for the 4.3 mm fibres. Heat shrinkage experiments were conducted by exposing the fibres to a temperature above their glass transition temperature (T g ). The test revealed a remarkable capability of the thinnest fibres to shrink by 50%, which was in contrast to the 4.3 mm fibres, which displayed only 4% shrinkage. These thinner fibres also showed a significantly higher glass transition temperature (+15 C) than that of the 4.3 mm fibres. The results suggested an internal morphology with a high degree of molecular orientation in the amorphous segments along the thinner fibres, consistent with a constrained mesomorphic phase formed during their rapid solidification in the electric field. Air filtration was demonstrated with cigarette smoke as a model substance passed through the fibre mats.The 0.4 mm fibres showed the most effective smoke filtration and a capacity to absorb 43Â its own weight in smoke residuals, whereas the 1 mm fibres showed the best combination of filtration capacity (32Â) and mechanical robustness. The use of recycled PET in the form of nanofibres is a novel way of turning waste into higher-value products.

The thermal, optical, flame retardant, and morphological consequence of embedding diacid‐capped ZnO into the recycled PET matrix

“…The XRD patterns of PET@ZnO/DA NCs indicate that XRD pattern of ZnO NPs has not been changed during the ultrasonication process and using modifier on the NPs surface. Also, according to Figure 2( 32 In the NCs diffraction patterns [ Figure 2(d-f)], intensity of diffraction peaks tends to increase with the increasing of the modified ZnO contents. Also, the degree of crystallinity gradually increased in compare with recycled PET.…”

Magnetism and white-light-emission bifunctionality simultaneously assembled into flexible Janus nanofiber via electrospinning

“…Electrospinning is an effective and simple method for preparing nanofibers with 1D nanostructure [27][28][29][30]. This method is applied in many areas such as filtration, optical and chemical sensors, biological scaffolds, electrode materials, drug delivery materials, photocatalysts, and nanocables [31][32][33][34][35][36][37]. Accordingly, here we employed electrospinning method to prepare magnetic and color- 3 phen)]/PVP nanofiber).…”

Phase separation behavior of poly(ethylene terephthalate)/(trifluoroacetic acid/dichloromethane)/water system for wet phase inversion membrane preparation

“…As well as for other polyesters, the utilization of PET for membrane fabrication by phase inversion technique is unwell explored, possibly due to the high chemical resistance of the polymer that makes it hard to find suitable solvents for its solubilization. On the other hand, electrospinning PET membranes are already being studied and applied in protein and pesticide filtration, showing that this material has potential in the field of membrane technology, including the possibility of using the recycled polymer for membrane fabrication . Some of the solvents being used to produce PET spinning solutions are the hexafluoroisopropanol, the trifluoroacetic acid (TFA), mixtures of TFA with dichloromethane (DCM), and phenol…”