Increasing interest in bio-based polymers and fibers has led to the development of several alternatives to conventional plastics and fibers made of these materials. Biopolymer fibers can be made from renewable, environmentally friendly resources and can be fully biodegradable. Biogenic resources with a high content of carbohydrates such as starch-containing plants have huge potentials to substitute conventional synthetic plastics in a number of applications. Much literature is available on the production and modification of starch-based fibers and blends of starch with other polymers. Chemistry and structure–property relationships of starch show that it can be used as an attractive source of raw material which can be exploited for conversion into a number of high-value bio-based products. In this review, possible spinning techniques for the development of virgin starch or starch/polymer blend fibers and their products are discussed. Beneficiation of starch for the development of bio-based fibers can result in the sustainable replacement of oil-based high-value materials with cost-effective, environmentally friendly, and abundant products.

Recycled fibers are commonly used in dissimilar applications and one of the most important applications is sound absorption. Recycled fiber nonwovens currently are in greater demands in industries because of their advantages such as low cost, biodegradability, acceptable mechanical and physical properties, and so on. Sound absorption materials, renewable, and eco-friendly nonwovens have been developed using recycled cotton and polyester fibers. This research provides a contribution to the body of knowledge on the sound absorption properties of nonwovens using recycled fibers which contain cotton and polyester by means of spun-laid technique and provides a better understanding of the effects of a number of manufacturing processes on nonwovens noise control performance and also contributes to the wider adoption of nonwovens as sound absorbers. The sound absorption coefficients were measured according to ASTM E 1050 by an impedance tube method. The results revealed that the average of the sound absorption coefficients increased with the thickness of the nonwovens, but decreased with the nonwoven fabric density.

The demand for sustainable textiles has increased research on bio-based biopolymers. Fiber spinning from starch biopolymer and its blends was widely attempted using electro-spinning; however, it is less attempted using melt spinning which is an industrially feasible method. In this study, native tapioca starch is converted into thermoplastic starch (TPS), blended with polylactic acid (PLA), and is attempted for melt spinnability in its neat and blended form TPS/PLA (70/30) with the intention of checking the possibility of melt spinning. The results from characterization of the prepared biopolymers show that thermal analysis of neat TPS does not reveal clear thermal transitions, glass transition ( T _g ), and melting ( T _m ), in the second heating curve, rather it influenced crystallization behavior of PLA as seen from differential scanning calorimetry result and degradation temperature ( T _d ) was found to be in the range of 296–352°C from thermogravimetric analysis showing that addition of PLA improved thermal stability of TPS. Morphology analysis with AFM images revealed the presence of granular starch in neat TPS and phase separation in TPS/PLA blends with finer phase distribution in the presence of additives. Fourier transform infrared spectroscopy result shows the interaction between starch, glycerol, and PLA showing the effect of thermoplasticization of starch which brings rupture or weakening of the strong glycosidic bonds in between starch molecules and interaction between TPS and PLA as it can be seen from peak shift and peak intensity. The melt spinning trials show the possibility of melt spinning TPS-based biopolymers into fibers even with higher content of TPS as well as neat TPS giving an insight and motivation for more research engagement. The melt-spun fibers were found to have a diameter in the range of 160.0–117.0 μm. However, additional experiments and investigations are required to improve the mechanical and other properties of the fibers.

Sizing is an established method for improving the weave ability of textile yarns. Sizing is the process of coating or impregnating warp yarns with a polymer that improves the efficiency of the weaving.

In this study, rheology, structure and melt spinnability of thermoplastic starch TPS/PLA blend compounds as well as characteristics of melt spun fibers was studied. Thermoplastic starch is further modified with tartaric acid and blends are compatibilized using graft copolymer, maleic anhydride grafted PLA. Results from rheology analysis of compounds shows significantly reduced melt flow rate MFR and reduced viscosity as a result of tartaric acid modification and compatibilization, but the viscosity was increased as TPS_TA content in the blend increased. In addition, storage modulus (G`) and loss modulus (G``) were increased with increasing TPS_TA content in the blends. Fourier transform infrared spectroscopy FTIR analysis confirmed O-H peak shifts and peak intensity changes associated to starch thermosplasticization and further peak shifts associated with more O-H bond breakages due to tartaric acid modification, indicating acid hydrolysis action of tartaric acid which agrees with results from rheology study. Melt spinning trials show the possibility of melt spinning of biopolymer fibers from blends with up to 40%w/w TPS_TA content. The melt spun fibers have diameter in range of 12.0–124.0 μm depending on take up speed and TPS_TA content. Differential scanning calorimetry DSC analysis of melt spun fibers shows glass transition Tg shifts attributed to molecular orientation and rigid amorphous TPS phase formation as well as the occurrence of double melting peaks Tm associated to different crystals resulting from induced crystallization. The overall result from this study shows the possibility of melt spinning thermoplastic starch/PLA blend biopolymers in to fibers, revealing opportunity to utilize starch biopolymer for fiber spinning. Furthermore, the results also show the need for further research engagements to get fibers with better performance.