Starch-based Biopolymer Research Articles

High-Performance-Tensile-Strength Alpha-Grass Reinforced Starch-Based Fully Biodegradable Composites

Though there has been a great deal of work concerning the development of natural fibers in reinforced starch-based composites, there is still more to be done. In general, cellulose fibers have lower strength than glass fibers; however, their specific strength is not far from that of fiberglass. In this work, alpha-fibers were obtained from alpha-grass through a mild cooking process. The fibers were used to reinforce a starch-based biopolymer. Composites including 5 to 35% (w/w) alpha-grass fibers in their formulation were prepared, tested, and subsequently compared with those of wood- and fiberglass-reinforced polypropylene (PP). The term “high-performance” refers to the tensile strength of the studied composites and is mainly due to a good interphase, a good dispersion of the fibers inside the matrix, and a good aspect ratio. The tensile strength of the composites showed a linear evolution for fiber contents up to 35% (w/w). The strain at break of the composites decreased with the fiber content and showed the stiffening effects of the reinforcement. The prepared composites showed high mechanical properties, even approaching those of glass fiber reinforced composites.

Biocomposites from Starch-based Biopolymer and Rape Fibers. Part I: Interfacial Analysis and Intrinsic Properties of Rape Fibers

Biocomposites from Starch-based Biopolymer and Rape Fibers. Part I: Interfacial Analysis and Intrinsic Properties of Rape Fibers

Biocomposites from Starch-based Biopolymer and Rape Fibers. Part II: Stiffening, Flexural and Impact Strength, and Product Development

Rape biomass was the raw material for the preparation of thermomechanical fibers, and it was used to reinforce starch-based biopolymer. In this study, the mechanical properties of the produced biocomposites, including flexural strength, Young’s and flexural moduli and impact strength, were characterized. Afterwards, the material properties were simulated to evaluate its suitability for substituting for oil-based raw materials. The results showed that the intrinsic flexural strength of rape fibers was 2.25 times of that of rape fibers. The impact strength of rape/starch biocomposites decreased with the increment in the reinforcement, even though the work to crack initiation slightly augmented with the fiber proportion increase. After the mechanical property analysis, the prepared biocomposites were tested as replacing materials for the development of real oil-based products. The engineering development stands out the feasibility of using these materials to develop new products truly based on bio-resources.

Preparation and characterization of lithium ion conducting ionic liquid-based biodegradable corn starch polymer electrolytes

Thin films of biodegradable corn starch-based biopolymer electrolytes were prepared by solution casting technique. Lithium hexafluorophosphate (LiPF6) and 1-butyl-3-methylimidazolium trifluoromethanesulfonate (BmImTf) were employed as lithium salt and ionic liquid, respectively. With reference to the temperature dependence study, Arrhenius relationship was observed. The highest ionic conductivity of (6.00 ± 0.01) × 10−4 S cm−1 was obtained at 80 °C. Based on x-ray diffraction (XRD) result, the peaks became broader with doping of ionic liquid revealing the higher amorphous region of the biopolymer electrolytes. Ionic liquid-based biopolymer electrolytes exhibited lower glass transition temperature (Tg).

Processing and properties of biodegradable composites based on Mater-Bi ® and hemp core fibres

While petroleum-derived polymers persist for many years after disposal, biopolymers inclined to degrade in bioactive environments. Moreover biopolymers are suitable to be reinforced by natural fibres, which behave as biodegradable fillers into a biodegradable matrix, to improve their mechanical performance. Among the biodegradable polymers, starch-based biopolymers are ones of the most intensity studied. Starch-based biopolymers are produced by blending thermoplastic starch with synthetic polymers resulting in different biopolymer morphology and final properties. In this work, lignocellulosic fibres from hemp core raw material were used as reinforcement of starch-based biopolymer and the final mechanical properties evaluated. Due to the similar chemical characteristics of both composite components, no one coupling agent was used to improve the biocomposite stress transfer. Hemp core fibres were obtained by means of a semi-chemical pulp process and biocomposites from starch-based biopolymer comprising 10, 20 and 30 wt% of reinforcement were prepared. The interfacial shear strength of the obtained composites, determined from Kelly–Tyson model, demonstrated the good quality at fibre–matrix interface for this type of composites.

Behavior of biocomposite materials from flax strands and starch-based biopolymer

In this work, a starch-based biopolymer was reinforced with flax strands. Composite materials at different fiber content were obtained by means of high-shearing mixing followed by injection molding processing. The evaluation of the mechanical properties gave a significant increase of the strength and stiffness of composites with the percentage of flax strands. The enhancement was analyzed in terms of compatibility and extension of the adhesion at fiber–matrix interface. The intrinsic mechanical properties of the reinforcement were measured and the behavior of the obtained composites was studied in terms of the modified rule of mixtures and the modified Halpin–Tsai equations.

Improvement of the impact performance of a starch based biopolymer via the incorporation of Miscanthus giganteus fibres

This paper examines the possibilities of using an established energy crop; Miscanthus giganteus as a filler/reinforcement in injection mouldable thermoplastic composites utilising a starch-based biopolymer; Novamont Mater-Bi as the matrix. A design of experiments methodology was used to reveal how varying the processing parameters and material formulation affected the impact performance of the biocomposite. The addition of Miscanthus fibres to the polymer results in composites with higher impact absorbance and loading than those of standard Mater-Bi.

Profile Modification Due to Polymer Adsorption in Reservoir Rocks

Flow behavior of a newly developed starch-based biopolymer is studied in the laboratory to gain insight into its ability and effectiveness to recover additional oil. This study analyzes permeability modification due to polymer adsorption in the porous media. Experiments are performed to determine the permeability reduction and the effects of polymer adsorption on capillary pressure curves. A model is developed to estimate the amount of polymer adsorbed in the porous media. The difference in pore size distribution before and after polymer flow indicates the effectiveness of polymer to modify the permeability profile. The difference in capillary pressure curves before and after polymer flow indicates the extent of polymer adsorption in the porous media.