Management of Corn Stalk Waste as Reinforcement for Polypropylene Injection Moulded Composites

Abstract

The main objective of this study was the management of corn stalk waste as reinforcement for polypropylene (PP) injection moulded composites as an alternative to wood flour and fibers. In the first step, corn stalk waste was subjected to various treatments, and four different corn stalk derivatives (flour and fibers) able to be used as reinforcement of composite materials were prepared and characterized. These derivatives are corn stalk flour, thermo-mechanical, semi-chemical, and chemical fibers. They were characterized in terms of their yield, lignin content, Kappa number, fiber length/diameter ratio, fines, coarseness, viscosity, and the length at the break of a standard sheet of paper. Results showed that the corn stalk derivatives have different physicochemical properties. In the second step, the prepared flour and fibers were explored as a reinforcing element for PP composites. Coupled and non-coupled PP composites were prepared and tested for tensile properties. For overall trend, with the addition of a coupling agent, tensile properties of composites significantly improved, as compared with noncoupled samples. In addition, a morphological study revealed the positive effect of the coupling agent on the interfacial bonding. The composites prepared with semichemical fiber gave better results in comparison with the rest of the corn stalk derivatives due to its chemical characteristics.

Comparison between two different pretreatment technologies of rice straw fibers prior to fiberboard manufacturing: Twin-screw extrusion and digestion plus defibration

“…In addition, a slight increase in the aspect ratio was observed with an increasing liquid/solid ratio (i.e. from 4 to 6) in the digester reactor and Waldron-Sprout defibrator, and such phenomenon was previously observed for twin-screw extrusion (Table 4) but also in the case of a steaming plus a mechanical defibration treatment (Alila et al, 2013;Flandez et al, 2012;Theng et al, 2015a). Such aspect ratio increase resulted mainly in the slight increase of the mean length of fibers, from 371 μm to 386 μm (i.e.…”

Macro and micromechanics analysis of short fiber composites stiffness: The case of old newspaper fibers–polypropylene composites

“…Virgin wood fibers and cellulosic fibers from recycled papers, when used as reinforcement with the adequate coupling agents, are able to increase both the elastic moduli and the strength of the composite materials [12][13][14][15][16][17][18][19]. The strength of natural fiber reinforced composites is highly influenced by the incompatibility between the hydrophilic fibers and the hydrophobic polymers.…”

Estimation of the interfacial shears strength, orientation factor and mean equivalent intrinsic tensile strength in old newspaper fiber/polypropylene composites

“…The virgin wood fibers and the cellulosic fibers from recycled papers had a higher aspect ratio (length by diameter ratio), and when are used as reinforcement with the adequate coupling agents, are able to increase both, the elastic moduli and the strength of the composite materials. The improvement of the elastic moduli is slightly superior to that obtained with particulate fillers [3][4][5][6][7][8][9]. The natural strands as jute, kenaf, flax, are the most effective cellulosic reinforcement fibers [2,[10][11][12][13][14][15].…”